Luminosity and Chromaticity: On Light and Color

Luminosity and Chromaticity: On Light and Color

Key Terms and Ideas

  • Luminosity and Chromaticity
  • Light and Color
  • Diwali (Festival of Light) and Holi (Festival of Colors)
  • Rama and Krishna
  • Non Dual Vedanta and Trika Philosophy
  • 1 and 3
  • Verticalism and Horizontalism
  • Vedic and Tantric
  • Flute of Krishna and Shiva Jyotir Linga
  • Bow and Arrow of Ram
  • Ram Parivar and Shiv Parivar
  • Shiv Ratri
  • Plato and Aristotle
  • Sun, Moon, Earth and Mars
  • Rods and Cones in Retina
  • Color Temperature
  • Lok and Kosh
  • Seven Chakra
  • Trishool
  • Ram, Lakshman, Sita, Hanuman
  • Achromatic and Chromatic
  • Grey scale and Color Primaries
  • Mind and Moon
  • Moon and Emotions
  • Tone Circle
  • Color Circle
  • Pythagoras
  • 3 and 7
  • 137
  • 007
  • Prism
  • Seven Colors
  • 4 + 3 = 7
  • 4 x 3 = 12
  • Pentatonic
  • Heptatonic
  • Diatonic Scale
  • Chromatic Scale

Newton’s Color Circle

Source: http://winlab.rutgers.edu/~trappe/Courses/ImageVideoS06/MollonColorScience.pdf

Color Circle in Opticks of I.Newton

Source: Reprint of Opticks by Project Gutenberg

Color Sensation

Source: Understanding color & the in-camera image processing pipeline for computer vision

Electromagnetic Spectrum

Source: Notes for the course of Color Digital Image Processing

Color Temperature

Source: Understanding color & the in-camera image processing pipeline for computer vision

Color Temperatures of the Stars

Luminosity Function

Source: Understanding color & the in-camera image processing pipeline for computer vision

CIE 1931 XYZ

Source: Understanding color & the in-camera image processing pipeline for computer vision

Luminance

Source: Human Vision and Color

Brightness, Lightness,Hue, Saturation, and Luminosity

Source: The Brightness of Colour

Brightness has been defined as the perceived intensity of a visual stimulus, irrespective of its source. Lightness, on the other hand, is defined as the apparent brightness of an object relative to the object’s reflectance. Thus increasing the intensity of light falling on an object will increase its apparent brightness but not necessarily its apparent lightness, other things being equal [1]. Saturation is a measure of the spectral ‘‘purity’’ of a colour, and thus how different it is from a neutral, achromatic stimulus. Hue is the perception of how similar a stimulus is to red, green, blue etc. Luminous efficiency, or luminosity, measures the effect that light of different wavelengths has on the human visual system. It is a function of wavelength, usually written as V(l) [2], and is typically measured by rapidly alternating a pair of stimuli falling on the same area of the retina; the subject alters the physical radiance of one stimulus until the apparent flickering is minimised. Thus luminance is a measure of the intensity of a stimulus given the sensitivity of the human visual system, and so is integrated over wavelength [3]. Luminance is thought to be used by the brain to process motion, form and texture [4].

Clearly, brightness is monotonically related to luminance in the simplest case: the more luminant the stimulus is, the brighter it appears to be. However, the Helmholtz-Kohlrausch (HK) effect shows that the brightness of a stimulus is not a simple representation of luminance, since the brightness of equally luminant stimuli changes with their relative saturation (i.e. strongly coloured stimuli appear brighter than grey stimuli), and with shifts in the spectral distribution of the stimulus (e.g. ‘blues’ and ‘reds’ appear brighter than ‘greens’ and ‘yellows’ at equiluminance) [1; 5–6].

The HK effect has been measured in a variety of psychophysical studies [7–8] and is often expressed in terms of the (variable) ratio between brightness and luminance. 

Chromaticity

Source: Human Vision and Color

Human Eye

Source: Human Vision and Color

Human Retina

Source: Human Vision and Color

Rods and Cones Photoreceptors

Source: Human Vision and Color

Color Receptors

Source: Human Vision and Color

Tristimulus Color

Source: Color/CMU

Visual Sensitivity

Source: Human Vision https://people.cs.umass.edu/~elm/Teaching/ppt/691a/CV%20UNIT%20Light/691A_UNIT_Light_1.ppt.pdf

Light and Color (Photometry and Colorimetry) I

Source: Interactive Computer Graphics/UOMichigan

Light and Color (Photometry and Colorimetry) II

Source: Interactive Computer Graphics/UOMichigan

Two Types of Light Sensitive Cells

Source: Interactive Computer Graphics/UOMichigan

Cones and Rod Sensitivity

Source: Interactive Computer Graphics/UOMichigan

Distribution of Cones in Retina

Source: DIVERSE CELL TYPES, CIRCUITS, AND MECHANISMS FOR COLOR VISION IN THE VERTEBRATE RETINA

Types of Color Stimuli

Source: Perceiving Color. https://www.ics.uci.edu/~majumder/vispercep/chap5notes.pdf

Color Perception

Source: Perceiving Color. https://www.ics.uci.edu/~majumder/vispercep/chap5notes.pdf

CIE XYZ Model

Source: Human Vision and Color

Luminance and Chromaticity Space

Source: Understanding color & the in-camera image processing pipeline for computer vision

1931 CIE Chromaticity Chart

CIE 1931 Chromaticity Diagram

Source: Human Vision and Color

Source: Notes for the course of Color Digital Image Processing

Additive Colors

Source: Human Vision and Color

Subtractive Colors

Source: Human Vision and Color

Color Mixing

Source: Human Vision and Color

Color Appearance Models
  • RGB
  • CMY
  • CIE XYZ
  • CIE xyY
  • CIE LAB
  • Hunter LAB
  • CIE LUV
  • CIE LCH
  • HSB
  • HSV
  • HSL
  • HSI
  • YIQ for NTSC TVs in USA
  • YUV for PAL TVs in EU
  • YCbCr for digital TVs
  • Munsell Color System

Color Models are device independent. For discussion of device dependent color spaces, please see my post Digital Color and Imaging.

LMS, RGB, and CIE XYZ Color Spaces

Source: Color/CMU

HSV Color Space

My Related Posts

Reflective Display Technology: Using Pigments and Structural Colors

Color Science and Technology in LCD and LED Displays

Color Science of Gem Stones

Nature’s Fantastical Palette: Color From Structure

Optics of Metallic and Pearlescent Colors

Color Change: In Biology and Smart Pigments Technology

Color and Imaging in Digital Video and Cinema

Digital Color and Imaging

On Luminescence: Fluorescence, Phosphorescence, and Bioluminescence

On Light, Vision, Appearance, Color and Imaging

Understanding Rasa: Yoga of Nine Emotions

Shapes and Patterns in Nature

Key Sources of Research

What Are The Characteristics Of Color?

https://www.pantone.com/articles/color-fundamentals/what-are-the-characteristics-of-color

Birren Color Theory

by ADMIN on MARCH 11, 2012

http://www.wonderfulcolors.org/blog/birren-color-theory/

Light, Color, Perception, and Color Space Theory

Professor Brian A. Barsky

barsky@cs.berkeley.edu

Computer Science Division
Department of Electrical Engineering and Computer Sciences University of California, Berkeley

Understanding Color Spaces and Color Space Conversion

https://www.mathworks.com/help/images/understanding-color-spaces-and-color-space-conversion.html

The Human Visual System and Color Models

Click to access Carmody_Visual&ColorModels.pdf

Defining and Communicating Color: The CIELAB System

Color Vision and Arts

http://www.webexhibits.org/colorart/index.html

PRECISE COLOR COMMUNICATION: COLOR CONTROL FROM PERCEPTION TO INSTRUMENTATION

KonicaMinolta

A short history of color theory

https://programmingdesignsystems.com/color/a-short-history-of-color-theory/index.html

Let’s Colormath

Understanding the formulas of color conversion

https://donatbalipapp.medium.com/colours-maths-90346fb5abda

A History of Human Color Vision—from Newton to Maxwell

Barry R. Masters

Optics and Photonics January 2011

https://www.osa-opn.org/home/articles/volume_22/issue_1/features/a_history_of_human_color_vision—from_newton_to_max/

The Difference Between Chroma and Saturation

Munsell Color

Charles S. Peirce’s Phenomenology: Analysis and Consciousness

By Richard Kenneth Atkins

The Evolution of Human Color Vision/ Jeremy Nathans

Jeremy Nathans Lecture on Color Vision

JEREMY NATHANS LECTURE ON COLOR VISION

JEREMY NATHANS LECTURE ON COLOR VISION

JEREMY NATHANS LECTURE ON COLOR VISION

The Genes for Color Vision

Jeremy Nathans

SCIENTIFIC AMERICAN FEBRUARY 1989

A Short History of Color Photography

Photography  |  Angie Kordic

https://www.widewalls.ch/magazine/color-photography

Blue: The History of a Color (2001)

followed by Black: The History of a Color (2009) and then Green: The History of a Color (2014), all produced by the same publisher. A fifth, devoted to yellow, should come next. 

Historic Look on Color Theory 

Steele R. Stokley

The evolution of colour in design from the 1950s to today

Francesca Valan

Journal of the International Colour Association (2012): 8, 55-60

Greek Color Theory and the Four Elements

J.L. Benson

University of Massachusetts Amherst

A SHORT HISTORY OF COLOUR PHOTOGRAPHY

https://blog.scienceandmediamuseum.org.uk/a-short-history-of-colour-photography/

History of Color System

The Origins of Modern Color Science

J D Mollon

Click to access MollonColorScience.pdf

The History of Colors

Tobias Kiefer

Click to access Assignment_History_of_Colors.PDF

Notes for the course of Color Digital Image Processing

Edoardo Provenzi

Understanding color & the in-camera image processing pipeline for computer vision

Dr. Michael S. Brown

Canada Research Chair Professor York University – Toronto

ICCV 2019 Tutorial – Seoul, Korea

Chapter 2
Basic Color Theory

Click to access t3.pdf

Color Science

CS 4620 Lecture 26

Click to access 26color.pdf

Color Image Perception, Representation and Contrast Enhancement

Yao Wang
Tandon School of Engineering, New York University

A GUIDE TO LIGHT AND COLOUR DEMONSTRATIONS

Arne Valberg, Bjørg Helene Andorsen, Kine Angelo, Barbara Szybinska Matusiak and Claudia Moscoso

Norwegian University of Science and Technology Trondheim, Norway

https://www.ntnu.edu/documents/1272527942/1272817015/2015-09-08+DEMO+web.pdf/f1695ca5-b834-4d05-a011-a185f6562e32

A Primer to Colors in Digital Design

Archit Jha

Jul 16, 2017

https://uxdesign.cc/a-primer-to-colors-in-digital-design-7d16bb33399e

Chapter 7 ADDITIVE COLOR MIXING

Click to access 07_additive-color.pdf

Computergrafik

Matthias Zwicker Universität Bern Herbst 2016

Color

Click to access ColorPerception.pdf

Introduction to Computer Vision

The Perception of Color

In: Webvision: The Organization of the Retina and Visual System [Internet]. Salt Lake City (UT): University of Utah Health Sciences Center; 1995–.2005 May 1 [updated 2007 Jul 9]

https://pubmed.ncbi.nlm.nih.gov/21413396/

Visual Pigment Gene Structure and Expression in Human Retinae 

Tomohiko Yamaguchi,  Arno G. Motulsky,  Samir S. Deeb

Human Molecular Genetics, Volume 6, Issue 7, July 1997, Pages 981–990, https://doi.org/10.1093/hmg/6.7.981

https://academic.oup.com/hmg/article/6/7/981/572151

The Difference Between Chroma and Saturation

LUMINANCE AND CHROMATICITY

https://colorusage.arc.nasa.gov/lum_and_chrom.php

Number by Colors

A Guide to Using Color to Understand Technical Data
  • Brand Fortner
  • Theodore E. Meyer

Chapter 5 Perceiving Color

The Practical Guide To Color Theory For Photographers

History of the Bauhaus

https://bauhaus.netlify.app/form_color/color/

The Digital Artist’s Complete Guide To Mastering Color Theory

byLeigh G

BASIC COLOR THEORY

Anthony Holdsworth

Molecular Genetics of Color Vision and Color Vision Defects

Maureen Neitz, PhDJay Neitz, PhD

Arch Ophthalmol. 2000;118(5):691-700. doi:10.1001/archopht.118.5.691

https://jamanetwork.com/journals/jamaophthalmology/fullarticle/413200

Color Theory: Introduction to Color Theory and the Color Wheel

https://blog.thepapermillstore.com/color-theory-introduction-color-wheel/

Color Spaces and Color Temperature

https://tigoe.github.io/LightProjects/color-spaces-color-temp.html

The Brightness of Colour

David Corney1, John-Dylan Haynes2, Geraint Rees3,4, R. Beau Lotto1*

EECS 487: Interactive Computer Graphics

Colorimetry

KonicaMinolta

Basics of Color Theory

THE BASICS OF COLOR PERCEPTION AND MEASUREMENT

Hunterlab

https://www.hunterlab.com/color-measurement-learning/glossary/

Color Matching and Color Discrimination

The Science of Color

2003

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.457.9467&rep=rep1&type=pdf

1.3 Color Temperature

https://www.mat.univie.ac.at/~kriegl/Skripten/CG/CG.html

https://www.mat.univie.ac.at/~kriegl/Skripten/CG/node10.html

Color Spaces and Color Temperature

https://tigoe.github.io/LightProjects/color-spaces-color-temp.html

Digital Camera Sensor Colorimetry

Douglas A. Kerr

Click to access Sensor_Colorimetry.pdf

Chromatic luminance, colorimetric purity, and optimal aperture‐color stimuli

DOI: 10.1002/col.20356

https://www.researchgate.net/publication/230164581_Chromatic_luminance_colorimetric_purity_and_optimal_aperture-color_stimuli

Title: A Review of RGB Color Spaces …from xyY to R’G’B’

The CIE XYZ and xyY Color Spaces

Douglas A. Kerr

Click to access CIE_XYZ.pdf

DIVERSE CELL TYPES, CIRCUITS, AND MECHANISMS FOR COLOR VISION IN THE VERTEBRATE RETINA

Wallace B. Thoreson and Dennis M. Dacey

Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska; and Department of Biological Structure, Washington National Primate Research Center, University of Washington, Seattle, Washington

Physiol Rev 99: 1527–1573, 2019 Published May 29, 2019; doi:10.1152/physrev.00027.2018

https://journals.physiology.org/doi/pdf/10.1152/physrev.00027.2018

Human Vision

Introduction to color theory

https://graphics.stanford.edu/courses/cs178-10/applets/locus.html

COLOR WHEELS

https://www2.bellevuecollege.edu/artshum/materials/art/tanzi/Winter04/111/111CLRWHLSW04.htm

Human Vision and Color

UT

Click to access 121.pdf

COLOR VISION MECHANISMS

Andrew Stockman

Department of Visual Neuroscience UCL Institute of Opthalmology London, United KIngdom

David H. Brainard

Department of Psychology University of Pennsylvania Philadelphia, Pennsylvania

Color

CMU

Click to access lecture15.pdf

What Are The Characteristics Of Color?

Pantone

https://www.pantone.com/articles/color-fundamentals/what-are-the-characteristics-of-color

A Guide to Color


Guide C-316
Revised by Jennah McKinley

https://aces.nmsu.edu/pubs/_c/C316/welcome.html

A History of Color

The Evolution of Theories of Lights and Color
  • Robert A. Crone

https://link.springer.com/book/10.1007/978-94-007-0870-9

The Brilliant History of Color in Art

Victoria Finlay

A History of Light and Colour Measurement
Science in the Shadows

Sean F Johnston

University of Glasgow, Crichton Campus, UK

Color codes: modern theories of color in philosophy, painting and architecture, literature, music and psychology

Charles Riley

Chapter 6 Colour

History of Color Systems

Color Science of Gem Stones

Color Science of Gem Stones

Key Terms

  • Iridescence Orient
  • Play-of-color Labradorescence
  • Chatoyancy (“cat’s-eye”) Asterism
  • Adularescence
  • Aventurescence
  • Change-of- color (“Alexandrite effect”)
  • Pearlescence
  • Opalescence

Causes of Color in Gemstones

Sourcez: AN UPDATE ON COLOR IN GEMS. PART 1: INTRODUCTION AND COLORS CAUSED BY DISPERSED METAL IONS

Three most common causes of color in gem materials:

  • Dispersed metal ions
  • Charge transfers and other processes that involve multiple ions, and colorcenters.
  • Coloration that are less often seen in gems, such as those that result from physical phenomena (asin opal) or from semiconductor-like properties (as in natural blue diamond).

Source: http://www.scifun.org/chemweek/ColorOfGemstones2017.pdf

THE COLORS OF GEMSTONES

The most common cause of color in gemstones is the presence of a small amount of a transition metal ion. These transition metal ions have an incomplete set of 3electrons. Changes in the energy of these electrons correspond to the energy of visible light. When white light passes through a colored gemstone or is reflected by it, some of the energy of the visible light is absorbed, causing 3electrons in the transition metal ion to undergo an energy change. The light that is transmitted or reflected appears colored, because those colors corresponding to 3d– electron energy transitions have been absorbed. The table lists several common gemstones, their chemical compositions, colors, and the origins of these colors.

A ruby is a crystal of alumina, aluminum oxide, containing a trace of chromium(III) ions replacing some of the aluminum ions. In ruby, each Al3+ ion and Cr3+ ion is surrounded by six oxide ions in an octahedral arrangement.

GemFormulaColorOrigin of color
RubyAl2O3RedCr3+ replacing Al3+ in octahedral sites
EmeraldBe3Al2(SiO3)6page1image48667408 page1image48670688Greenpage1image48674080Cr3+ replacing Al3+ in octahedral site
AlexandriteAl2BeO4page1image48684352 page1image48679952Red/Greenpage1image46942720Cr3+ replacing Al3+ in octahedral site
GarnetMg3Al2(SiO4)3page1image46978464 page1image46979040Redpage1image46980384Fe2+ replacing Mg2+ in 8- coordinate site
page1image47140576 page1image47141088PeridotMg2SiO4Yellow-greenFe2+ replacing Mg2+ in 6- coordinate site
page1image47154784 page1image47155296T ourmalinepage1image47156576 page1image47157088Na3Li3Al6(BO3)3(SiO3)6F4PinkMn2+ replacing Li+ and Al3+ in octahedral site
TurquoiseAl6(PO4)4(OH)84H2OBlue-greenCu2+ coordinated to 4 OH and 2 H2O
Sapphirepage1image88097760 page1image88100240Al2O3BlueIntervalence transition between Fe2+ and Ti4+ replacing Al3+ in adjacent octahedral sites

This arrangement splits the five 3orbitals of Cr3+ into two sets, the dxy, dxz, dyz orbitals and the dx2-y2 and dz2 orbitals. These two sets have different energies. The energy difference between these sets corresponds to the energy of visible light. When white light strikes a ruby, the gem absorbs the light of energy corresponding to the transition of an electron from the lower-energy set of 3orbitals to the higher-energy set. The ruby reflects or transmits the remainder of the light. Because this light is deficient in some energies (those that were absorbed), the light appears colored.

The origin of the color of emeralds is similar to that of the color of rubies. However, the bulk of an emerald crystal is composed of beryl, beryllium aluminum silicate, instead of the alumina which forms rubies. The color is produced by chromium(III) ions, which replace some of the aluminum ions in the crystal. In emeralds, the Cr3+ is surrounded by six silicate ions, rather than the six oxide ions in ruby. These silicate ions also split the 3orbitals of Cr3+ into two sets. However, the magnitude of the energy difference between the sets is different from that produced by the oxide ions in ruby. Therefore, the color of emeralds is different from that of ruby.

Chromium(III) also produces color in alexandrite. The color of this gem is very unusual, because in bright sunlight it appears green, but in incandescent light it appears red. This unusual behavior is a result of the way human vision works. Our eyes are most sensitive to green light. Alexandrite reflects both green and red light. In bright sunlight, the proportion of green light is greater than it is in the light from an incandescent lamp. The light reflected by alexandrite in bright sunlight is rich in green light, to which our eyes are most sensitive, and we perceive the gem as green. The light reflected by alexandrite in incandescent light is much richer in red, and we see the stone as red under these conditions.

Energy transition of the 3orbitals of other transition metal ions are responsible for the colors of other gemstones. Iron(II) produces the red of garnets and the yellow-green of peridots. Manganese(II) is responsible for the pink coloration of tourmaline, and copper(II) colors turquoise.

In some gemstones, the color is caused not by energy changes in a single transition metal ion, but by the exchange of electrons between two adjacent transition metal ions of differing oxidation states. The energy needed to transfer an electron from one ion to another corresponds to the energy of visible light. An example is sapphire. The bulk of sapphire is alumina, as in rubies, but some adjacent pairs of Al3+ ions are replaced by an Fe2+ ion and a Ti4+. When light of the appropriate energy strikes the crystal, energy is absorbed, and an electron moves from the Fe2+ to the Ti4+. Such a movement is called an intervalence transition. An intervalence transition is also responsible for the blue color of aquamarine. In aquamarine, adjacent Al3+ ions in beryl are replaced by an Fe2+ ion and an Fe3+ ion.

Not all gem colors are produced by transition metal ions. In some gemstones, the colors are produced by the presence of foreign atoms with a different number of valence electrons than the ones they replace. These foreign atoms are called color centers. Because the replacement atoms have the wrong number of valence electrons, they can supply or receive an electron from another atom by an intervalence transition. These color centers are often produced by nuclear transformation. An example of such a transformation is the change of a radioactive carbon- 14 atom in diamond into a nitrogen atom through beta particle emission. This leaves an atom of nitrogen in place of the original carbon atom. The nitrogen atom has one more valence electron than the carbon atom. These nitrogen atoms are the cause of the coloration of blue and yellow diamonds. Color centers can be caused artificially as well, by irradiating the gem in a nuclear reactor. Many bright blue and bright yellow diamonds are produced artificially in this manner.

REFERENCES

Chemistry in Britain, 1983, page 1004.
Gems and Gemology, Volume 17, 1981, page 37. Scientific American, October 1980, page 124.

Precious Stones

  • The Diamond
  • The Pearl
  • The Ruby
  • The Sapphire
  • The Emerald
  • The Oriental Cateye
  • The Alexandrite

RGB Colors of Gemstones

Blue Sapphire

Emerald

Ruby

Pearl

Tahitian Cultured Pearls

Diamond

Chrysoberyl (Oriental Cat’s Eye)

Alexandrite

Change in Color due to change in Illuminant

Semi Precious stones

  • The Amethyst
  • The Topaz
  • The Tourmaline
  • The Aquamarine
  • The Chrysoprase
  • The Peridot
  • The Opal
  • The Zircon
  • The Jade
  • The Garnet
  • The Lapis lazuli
  • The Moonstone
  • The Spinel
  • The Turquoise
  • The Agate
  • The Coral
  • The Citrine
  • The Onyx
  • The Chrysolite
  • The Amber
  • The Chrysoberyl
  • The Chalcedony
  • The Morganite
  • The Quartz
  • The Tanzanite

Amethyst

Topaz

London Blue Topaz

Blue Topaz

Tourmaline

The Aquamarine

Chrysoprase

The Peridot

The Opal

The Zircon

The Jade

Garnet

Lapis lazuli

The MoonStone

White Moonstone

Grey Moonstone

The Spinel

Turquoise

Agate

Red Agate

Citrine

Onyx Black

 Chalcedony

Rose Quartz

Color Chemistry of Gemstones

Healing Power of Gemstones and Crystals

Precious Stones and Semi Precious Stones arranged by Color

Precious and Semi Precious Stones and their characteristics

Birthstones by Month

Source: AN UPDATE ON COLOR IN GEMS. PART 3: COLORS CAUSED BY BAND GAPS AND PHYSICAL PHENOMENA

My Related Posts

Nature’s Fantastical Palette: Color From Structure

Optics of Metallic and Pearlescent Colors

Color Change: In Biology and Smart Pigments Technology

Color and Imaging in Digital Video and Cinema

Digital Color and Imaging

On Luminescence: Fluorescence, Phosphorescence, and Bioluminescence

On Light, Vision, Appearance, Color and Imaging

Key Sources of Research

COLOR IN GEMS: THE NEW TECHNOLOGIES

By George R. Rossman

https://www.semanticscholar.org/paper/Color-in-Gems%3A-The-New-Technologies-Rossman/6202b8b7c6bf5db326a4f173813f0e7bd4943c69

A Primer of Gemstones

Nova

https://www.pbs.org/wgbh/nova/article/gemstone-primer/

THE COLORS OF GEMSTONES

Click to access ColorOfGemstones2017.pdf

An UPDATE ON COLOR IN GEMS. PART 1: INTRODUCTION AND COLORS CAUSED BY DISPERSED METAL IONS

By Emmanuel Fritsch and George R. Rossman

AN UPDATE ON COLOR IN GEMS. PART 2: COLORS INVOLVING MULTIPLE
ATOMS AND COLOR CENTERS

By Emmunuel Fritsch and George R. Rossinun

AN UPDATE ON COLOR IN GEMS. PART 3: COLORS CAUSED BY BAND GAPS AND
PHYSICAL PHENOMENA

By Emmanuel Fritsch and George R. Rossman

What Causes the Colour of Gemstones?

What Causes the Colour of Gemstones?

Concerning Precious Stones and Jewels

Issued by Theodore A. Kohn & Son
Jewellers, New York

Palagems

http://www.palagems.com/concerning-precious-stones

7 Gemstone Legends That Will Blow Your Mind

Angara

GEOSC 110H: The Science of Gemstones

Penn State

Gemstones

LEE ANDREW GROAT

https://www.americanscientist.org/article/gemstones

Source of many Images

https://www.leibish.com/rings-jewelry/mozambique-no-heat-pigeon-blood-ruby-three-stone-ring-28510

The origins of color in minerals

KURT NASSAU

Bell Laboratories

Murray Hill, New Jersey 07974

American Mineralogist

Volume 63, pages 219-229, 1978

http://www.minsocam.org/MSA/collectors_corner/arc/color.htm

THE EARLY HISTORY OF GEMSTONE TREATMENTS

By Kurt Nassau

A QUICK GUIDE TO PEARL COLORS

DNA Fingerprinting of Pearls to Determine Their Origins

DOI: 10.1371/journal.pone.0075606

https://www.researchgate.net/publication/257840043_DNA_Fingerprinting_of_Pearls_to_Determine_Their_Origins

New developments in cultured pearl production: use of organic and baroque shell nuclei


January 2013
Authors: Laurent E Cartier University of Lausanne
Michael S. Krzemnicki at University of Basel

https://www.researchgate.net/publication/276269725_New_developments_in_cultured_pearl_production_use_of_organic_and_baroque_shell_nuclei

Blue Nile

https://www.bluenile.com/

Alexandrite Effect: Gemstones That Change Color in Different Light

http://www.geologyin.com/2017/03/alexandrite-effect-not-all-white-light.html

What is Chrysoprase?

http://geologylearn.blogspot.com/2016/12/chrysoprase-gemstone.html

10 World Famous Gemstones

PUBLISHED FRI, JUL 11 200810:07 AM EDTUPDATED WED, JAN 29 20143:11 PM EST

Jessica Mark

https://www.cnbc.com/2008/07/11/10-World-Famous-Gemstones.html

The Causes of Color

Kurt Nassau

Gem Diamonds: Causes of Colors

Hiroshi Kitawaki

Gemmological Association of All Japan, Ueno 5-25-11, Taito-ku, Tokyo 110-0005, Japan (Received 9 May 2007; accepted 1 August 2007)

New Diamond and Frontier Carbon Technology

Vol. 17, No. 3 2007 MYU Tokyo

NDFCT536_full.pdf

Causes of Color in Minerals and Gemstones 

Paul F. Hlava, Sandia National Laboratories pfhlava@sandia.gov


Nature’s Fantastical Palette: Color From Structure

Nature’s Fantastical Palette: Color From Structure

Peacock Feathers

Source: STRUCTURAL COLORATION IN NATURE

Key Terms

  • Iridescence
  • Nanostructures
  • Color from Pigments
  • Color from Structures
  • Smart Pigments
  • Material Science
  • Color from Bioluminescence
  • Color Change
  • Photonics
  • Biomimicry
  • Non Iridescent Colors
  • Iridescent Colors
  • Photonic Crystals (PhC)
  • Diffraction Grating
  • Specular Reflection
  • Braggs Diffraction
  • 1D Grating
  • 2D and 3D Photonic Crystals
  • Optical Nanotechnology
  • Multilayer Filters
  • Biomimetics
  • Peacock
  • Morpho Butterflies
  • Interference
  • Colloidal Crystals
  • Colloidal Amorphous Array
  • Microfluidics
  • Photonic Pigments
  • Reflective Displays (E-Ink)
  • Colloidal Assembly
  • Photonic Glass (PG)
  • Plasmonic Films
  • Inverse-Opals
  • Braggs Stacks
  • Dielectric Structural Colors
  • Plasmonic Structural Colors
  • Amorphous Photonic Structures
  • Melanin
  • Dopamine
  • Poly Dopamine
  • Plasmonic Metasurfaces

Source: GOLD BUGS AND BEYOND: A REVIEW OF IRIDESCENCE AND STRUCTURAL COLOUR MECHANISMS IN BEETLES (COLEOPTERA)

Source: GOLD BUGS AND BEYOND: A REVIEW OF IRIDESCENCE AND STRUCTURAL COLOUR MECHANISMS IN BEETLES (COLEOPTERA)

Source: Structural color and its interaction with other color-producing elements: perspectives from spiders

Color Vision

Source: Structural Color and Odors: Towards a Photonic Crystal Nose Platform

Color Sources

  • From Pigments
  • From Bioluminescenece
  • From Structure

Source: Chromic Phenomena: Technological Applications of Colour Chemistry

Source: Chromic Phenomena: Technological Applications of Colour Chemistry

Structural Color in Nature

  • Peacock
  • Butterflies
  • Beetles
  • Parrots
  • Birds
  • Moth

Peacock Colors

Feathers of Peacock

Source: Structural colors: from natural to artificial systems

Colors of Marpho Butterfly

Closeup of Marpho Butterfly

Structure and Color

  • Iridescent – (Colloidal Crystals)- Angle Dependent – Regular Structure
  • Non Iridescent – (Colloidal Amorphous Arrays) – Angle Independent – Irregular Structure

Optics of Structural Colors

  • Interference
  • Diffraction Gratings
  • Scattering
  • Reflection

Nano Structures Responsible for Colors

Source: Structural color and its interaction with other color-producing elements: perspectives from spiders

  • Christmas Tree
  • Multilayer – 1 D Periodicity
  • Photonic Crystals – 2 D and 3 D
  • Diffraction Grating
  • Quasi Ordered Photonic Crystal
  • Disorder Structure

Source: BIO-INSPIRED VARIABLE STRUCTURAL COLOR MATERIALS

  • 1 D Gratings
  • 1 D Periodicity Multilayers
  • 1 D Discrete Periodicity
  • 2 D Gratings
  • 2 D Periodicity
  • Closed Packed Spheres of Solid Materials
  • Inverse Opal Analogoues

Source: STRUCTURAL COLORATION IN NATURE

  • Thin Film Interference
  • Multi Film Interference
  • Diffraction Gratings
  • Coherent Scattering
  • Incoherent Scattering
  • 1 D Photonic Crystals
  • 2 D Photonic Crystals
  • 3 D Photonic Crystals

Source: Structural Color and Odors: Towards a Photonic Crystal Nose Platform

Source: PHYSICS OF STRUCTURAL COLORS

Source: PHOTOPHYSICS OF STRUCTURAL COLOR IN THE MORPHO BUTTERFLIES

Source: Gold bugs and beyond: a review of iridescence and structural colour mechanisms in beetles (Coleoptera)

  • Cuticular Multilayer Reflector
  • Epicuticular Reflector
  • Exocuticular Reflector
  • Endocuticular Reflector

Source: Gold bugs and beyond: a review of iridescence and structural colour mechanisms in beetles (Coleoptera)

  • Multilayer Reflectors
  • Diffraction Gratings
  • 3 D Photonic Crystals

Multilayer reflectors in beetles have also been described as ‘thin-layer stacks’, ‘one-dimensional photonic crystals’ and ‘thin-film reflectors’ (e.g. Parker 1998, 2002; Vigneron et al. 2006). The vocabulary used to describe these structures is somewhat dispersive, as the variously intersecting disciplines of entomology, physics and applied optics (e.g. laser technology, fibre-optic data transmission, telescopes and microscopy) have all developed slightly different suites of terminology. Other synonyms for ‘multilayer reflector’ include multilayer stack, quarter wave stack, interference reflector and dielectric mirror.

We propose that the term multilayer reflector be applied to such structures in Coleoptera; this describes the multilayered nature of cuticular chitin lamellae (which are not true films) and the reflective mechanism by which colour is produced.

The terms ‘metallic colours’ or ‘metallic iridescence’ can be used to distinguish multilayer effects from those produced by other optical structures. Multilayer reflectance can typically be diagnosed as such by its limited palette (usually one or two apparent hues per reflector), blue shift with decreased observation angle and fixed position on the cuticle surface.

Source: Gold bugs and beyond: a review of iridescence and structural colour mechanisms in beetles (Coleoptera)

Three-dimensional crystalline structures producing scintillating, gem-like reflectance were described by Parker et al. (2003) in the entimine weevil Metapocyrtus sp. (initially misidentified as Pachyrrhynchus argus); by Welch et al. (2007) in Pachyrrhynchus congestus, and recently in another entimine weevil, Lamprocyphus augustus, by Galusha et al. (2008). The photonic crystals found in the scales of pachyrrhynchine weevils (Pachyrrhynchus and Metapocyrtus) have a close-packed hexagonal arrangement analogous to (mineral) opal, while the photonic crystal of Lamprocyphus has a diamond-based lattice (i.e. a face-centred cubic system rather than a hexagonal one).

Although the term ‘photonic crystal’ applies to any ordered subwavelength structure that affects the propagation of specific wavelengths of light (Parker & Townley 2007), it is the three-dimensionally ordered structures to which the term is most commonly applied. We recommend use of the term ‘three-dimensional photonic crystal’, which distinguishes these structures from the one-dimensional periodicity of multilayer reflectors or Bragg gratings. The terms ‘opal’ and ‘diamond based’ have been used to describe iridescence in weevil scales, but refer to phenomena that are relatively similar from an organismal perspective; it is important to note that these terms refer to crystalline lattice morphology and not the appearance of the scales themselves. Maldovan & Thomas (2004) provided an excellent overview of diamond-based lattice morphology (as observed in Lamprocyphus) in photonic crystals; Yablonovitch (1993) provided a thorough introduction to the photonic band-gap mechanism by which colours are produced in three-dimensional photonic crystals.

Source: Gold bugs and beyond: a review of iridescence and structural colour mechanisms in beetles (Coleoptera)

A diffraction grating is any nanoscale array of parallel ridges or slits that disperses white light into its constituent wavelengths (figure 8a shows a grating in cross section). Because white light consists of many different wavelengths, it diffracts into full spectra, creating the rainbow-like reflectance shown in figures 1a,b, 8c and 9b,d. While man-made diffraction gratings can disperse light via reflection or transmission, all beetle gratings are strictly reflection mechanisms.

Source: Gold bugs and beyond: a review of iridescence and structural colour mechanisms in beetles (Coleoptera)

http://photobiology.info/Ball.html

Nature’s Fantastical Palette: Color from Structure

Philip Ball
18 Hillcourt Road
East Dulwich
London SE22 0PE, UK
p.ball@btinternet.com

The changing hues of a peacock’s splendid tail feathers have always captivated the curious mind (Figure 1). The seventeenth-century English scientist Robert Hooke called them ‘fantastical’ because the colors could be made to disappear by wetting the feathers (Hooke, 1665). Using the newly invented microscope, Hooke looked at peacock feathers and saw that they were covered with tiny ridges, which he figured might be the origin of the colors. 

Figure 1

Figure 1. The shifting colors of the peacock’s tail have had metaphorical interpretations for centuries.

Hooke was on the right track. The bright, often iridescent colors of bird plumage, insect cuticle and butterfly wings are ‘structural’; produced not by light absorption by pigments, but light scattering from a regular array of objects just a few hundreds of nanometers (millionths of a millimeter) in size (Vukusic & Sambles, 2003; Vukusic, 2004; Wolpert, 2009). This scattering favors particular wavelengths depending on the size and spacing of the scatterers, and so it picks out specific colors from the full spectrum of sunlight. Because the precise hue may depend also on the viewing angle, structural colors are often iridescent, changing from blue to green or orange to yellow. And because they involve reflection rather than absorption, these colors can be startlingly brilliant. The Blue Morpho butterflies of South and Central America are visible from a quarter of a mile away, seeming almost to shine when sunlight penetrates the tropical forest canopy and bounces off their wings. 

Structural colors are just one example of how living organisms manipulate and channel light using delicately arranged micro- and nanostructures. These biological designs offer inspiration to engineers seeking to control light in optical technologies, and could lead to more brilliant visual displays, new chemical sensors, and better storage, transmission and processing of information. To make effective use of such tricks, we need to understand how nature creates and deploys these tiny optical structures; indeed, we must learn a new language of color production and mixing. 

Rather little is known about how many of these biological structures are put together, how they evolved, and how evolution has made creative use of the color and light effects they offer. But one thing is clear; nature doesn’t have the sophisticated patterning technologies, such as drilling with electron beams, that microengineers can use to laboriously carve such structures from solid blocks. Ingenuity is used instead of finesse; these biological structures must make themselves from the component parts. 

If we can master that art, we might develop new, cheap technologies to make such things as materials that change color or appearance, like the camouflage skins of some fish and squid, or fibres that guide and channel light with virtually no leakage, or chemically controlled light shutters. Here I look at some of nature’s tricks for turning structure into color; and the ways they are being exploited in artificial materials and devices (Ball, 2012). 

Layers

Although the ridges seen by Hooke on butterfly wing scales do scatter light, the bright colors of the reflected light generally come from invisible structures beneath the surface. In the natural world, they offer a robust way of generating color that is not hostage to the fate of delicate, light-sensitive organic pigments. 

The colored scales and feathers of birds, fish and butterflies typically contain organized microscopic layers or rods of a dense light-scattering material embedded in a matrix of a different substance. Because the distance between the scatterers is roughly the same as the wavelengths of visible light, the stacks cause the wave phenomenon of diffraction, in which reflected waves interfere with one another. Depending on the angle of reflection, light rays of a certain wavelength interfere constructively when they bounce off successive layers in the stack, boosting the corresponding color in the reflected light (Vukusic and Sambles, 2003; Vukusic, 2004; Wolpert, 2009). It is much the same process that elicits the chromatic spectrum in light glancing off a tilted CD. 

In butterfly wing scales the reflecting stacks are made of cuticle; a hard material containing the natural polymer chitin, separated by air-filled voids. In bird feathers, the stacks are platelets or rods of the dark pigment melanin; sometimes hollow, as in the Black Inca hummingbird, Coeligena prunellei, embedded in keratin, the protein from which our hair and fingernails are made (Figure 2). Analogous diffraction gratings made from alternating ultrathin layers of two materials are widely used in optical technologies to select and reflect light of a single color. For example, mirrors made from multiple layers of semiconductors are used as reflectors and color filters in devices ranging from astronomical telescopes to solid-state lasers and spectrometers. 

Figure 2

Figure 2. The iridescent blues and greens in the feathers of hummingbirds such as this Black Inca (left; part of blue iridescence highlighted with white box) are created by platelets of melanin pigment punctuated with air holes (right), which act as a photonic crystal to reflect light of a particular wavelength. K=keratin, A=air, M=melanin. (From Shawkey et al., 2009)

The male bird of paradise Lawes’ parotia (Parotia lawesii) has a particularly neat twist on this trick (Figure 3). The barbules (hair-like structures on the feather barbs) of its breast feathers contain layers of melanin spaced at a distance that creates bright orange-yellow reflection. But, as Stavenga and colleagues have recently discovered, each barbule has a V-shaped or boomerang cross-section, with sloping surfaces that also act as reflectors of blue light (Stavenga et al., 2011). Slight movements of the feathers during the bird’s courtship ritual can switch the color abruptly between yellow-orange and blue-green; guaranteed to catch a female’s eye. Stavenga suspects that technologists will want to use this trick for producing dramatic chromatic shifts. “I suspect the fashion or automobile industries will in due time make bent structures or flakes that will exploit these angular color changes”, he says. 

Figure 3a
Figure 3b

Figure 3. A striking color change in the feathers of the male Lawes’ parotia, from yellow-orange (a) to blue-green (b), is caused by the presence of two mirror-like reflectors in the feather barbules (c): layers of melanin rods reflect yellow light, while the sloping faces of the boomerang-shaped barbule cross-section reflect blue at oblique angles. Scale bar in b: 1 cm. (From Stavenga et al., 2011)

Christmas Trees

The butterflies Morpho didius and Morpho rhetenor obtain their dazzling blue color not from simple multilayer’s but from more complex nanostructures in the wing scales: arrays of ornate chitin ‘Christmas Trees’ that sprout at the surface (Vukusic & Sambles, 2003) (Figure 4). Each ‘tree’ presents a stack of disk-like layers to the incoming light, which acts as another kind of diffraction grating. These arrays may reflect up to 80 percent of the incident blue light. And because they are not flat, they can reflect a single color over a range of viewing angles, somewhat reducing the iridescence; organisms don’t always want to change color or get dimmer when seen from different directions. 

Figure 4

Figure 4. The butterfly Morpho didius (left) obtains its dazzling blue color from delicate ‘Christmas Tree’ light-scattering structures (right), made from chitin, that sprout within the wing scales. (Left, courtesy of Peter Vukusic. Right (micrograph) from Vukusic and Sambles, 2003.)

The precise color reflected depends on the refractive index contrast between the nanostructures and the surrounding medium. This is usually air, but as Robert Hooke observed, wetting such surfaces alters the refractive index contrast, and changes the color in a way that is closely linked to the wetting liquid’s refractive index. For that reason, artificial Morpho-like structures carved into solids using microlithographic techniques are being developed by researchers at GE Global Research in New York, in collaboration with others at the State University of New York at Albany and butterfly-wing expert Pete Vukusic at the University of Exeter in England, as color-change chemical sensors that can identify a range of different liquids (Potyrailo, 2011). These might find applications for sensing emissions at power plants, monitoring of food safety, and testing of water purity. 

Reflecting Bowls

The bright green color of the Emerald Swallowtail butterfly (Papilio palinurus), found widely in southeast Asia, is not produced by green light at all. The wing scales are covered with a honeycomb array of tiny bowl-shaped depressions just a few micrometers across, lined with alternating layers of chitin cuticle and air which act as reflective mirrors. Light bouncing off the bottoms of the bowls is preferentially reflected in the yellow part of the spectrum. But from the sides it is reflected twice before bouncing back, and this selects blue. Our eyes can’t resolve these yellow spots and blue rings, which merge to create the perception of green (Vukusic & Sambles, 2003). 

Figure 5

Figure 5. The green of the Emerald Swallowtail butterfly (left) comes from the optical mixing of blue and yellow reflections from tiny bowl-like depressions in the wing scales (right). (Right figure, courtesy of Christopher Summers, Georgia Institute of Technology) 

This way of making color has been copied by Summers and coworkers (Crne et al., 2011). To create the tiny bowls, they let water vapour condense as microscopic droplets, called breath figures, on the surface of a polymer dissolved in a volatile solvent. The solvent gradually evaporates to form a solid polymer film, while the water droplets pack together on the surface of the drying solution much like greengrocers’ oranges and apples in crates, sinking into the setting film to imprint an array of holes. By pulling off the top part of the film, Summers and colleagues were left with a surface with hemispherical bowl-like dimples. They then used this structure as a template on which they deposited alternating thin layers of titania and alumina to make a multilayer reflector, like that lining the bowls of the butterfly wing scales (Figure 6). 

Figure 6

Figure 6. An artificial micro-structured surface that mimics the green color of the Emerald Swallowtail. Scale bar: 5 µm. (Courtesy of Christopher Summers, Georgia Institute of Technology)

Because each reflection changes the polarization of the light, under crossed polarizing filters the yellow light bouncing back from a single reflection at the bowl centers disappears, while the twice-reflected blue-green light from the rims remains. This could offer a distinctive authentification mark on bank and credit cards. Apparently just a simple green reflective coating, such a material would in fact carry a hidden polarized signature in the reflected blue and yellow light that would be hard to counterfeit. But Summers’ collaborator Mohan Srinivasarao admits that the main reason for seeking to replicate the butterfly’s green color was that “it’s beautiful in its own right”. 

Ordered Nanosponges

Scattering by regular arrays of microscopic objects can, for some arrangements, totally exclude light within a particular band of wavelengths, called the photonic band gap (Vukusic, 2004). These so-called photonic crystals occur naturally, for example, in opal, a biogenic form of silica in which the scatterers are tiny mineral spheres. Artificial photonic crystals can be used to confine light within narrow channels, creating waveguides that might be deployed to guide light around on silicon chips for optical information technology. 

Nature has already got there first. Under the electron microscope, the wing scales the Emerald Patched Cattleheart Butterfly (Parides sesostris) display zigzagging, herring-bone arrays: patches of an orderly sponge made from chitin with holes a hundred nanometers or so across. Each patch is a photonic crystal seen from a different alignment. Stavenga and Michielsen have found that these labyrinths in the wing-scales of P. sesostris and some species of papilionid and lycaenid butterflies have a structure known to mathematicians as a gyroid (Michielsen & Stavenga, 2008). In P. sesostris the structure has a photonic band gap that enables it to reflect light within the green part of the spectrum over a wide range of incident angles (Figure 7). Some weevils and other beetles also derive their iridescent color from three-dimensional photonic crystals made of chitin. 

Figure 7

Figure 7. The wing scales of P. sesostris (top left, and close-up, top right) contain photonic crystals of chitin (bottom, middle and right) Scale bars: left, 100 µm; middle, 2 µm; right, 2 µm. (Bottom figure, from Saranathan et al., 2010)

Richard Prum and coworkers have figured out how these photonic crystals grow (Saranathan et al., 2010). The molecules in the soft membranes that template the deposition of chitin during wing-scale growth become spontaneously organized into the ‘crystalline sponge’. Biological membranes are made up of long, tadpole-like molecules called lipids, which have a water-soluble head and an oily tail. To shield the tails from water, they cluster side by side into sheets with the heads pointing outwards; the sheets then sit back to back in bilayer membranes. Pores in these membrane induce curvature, partly exposing the lipid tails and therefore incurring a cost in energy. For this reason, the pores in effect repel one another, and this can force them to become arranged in a regular way, an equal distance apart. Periodic membrane structures have been found in the cells of many different organisms, from bacteria to rats (Hyde et al., 1997). 

In P. sesostris wing-scale progenitor cells, the outer ‘plasma membrane’ and the folded membrane of the inner compartments called the endoplasmic reticulum, where lipids and other molecules are made, come together to form a so-called double-gyroid structure (Figure 8, left), in which two interweaving sets of channels divide up space into three networks that interpenetrate, but are isolated from one another. One of these is then filled with chitin, which hardens into a robust form while the cell dies and the rest of the material is degraded, leaving behind the single gyroid phase (Saranathan et al., 2010). 

It has been suggested that these natural nanostructures might be used as the templates for making artificial ones, for example, by filling the empty space around the chitin with a polymer or an inorganic solid, and then dissolving away the chitin (Saranathan et al., 2010). But it is also possible to mimic the structures from scratch. For instance, artificial bilayer membranes made from lipid-like molecules called surfactants will also form orderly sponges, and so will so-called block copolymers, in which the chain-like molecules consist of two stretches with different chemical composition (Hyde et al., 1997). Ulrich Wiesner and coworkers (Stefik et al., 2012) have mixed liquid block copolymers with nanoparticles of niobium and titanium oxide, and let the polymers form into gyroid and other ordered ‘nanosponge’ structures that usher the nanoparticles into the same arrays. When this composite is heated, the polymer is burnt away while the mineral nanoparticles coalesce into continuous networks (Figure 8, center). 

These porous solids could find a wide range of uses. Thin porous films of titanium dioxide nanoparticles coated in light-absorbing dyes are already used in low-cost solar cells. These orderly gyroid networks can offer improvements, partly because the solid material through which light-excited electrons are harvested is continuously connected rather than relying on random electrical contacts between nanoparticles. And the researchers have calculated that double-gyroid nanosponges made from metals such as silver or aluminum, which might similarly be assembled from nanoparticles guided by block copolymers, could have the weird property of a negative refractive index, meaning that they would bend light ‘the wrong way’ (Hur et al., 2011). Such materials could be used to make so-called superlenses for optical microscopes that can image objects smaller than the wavelength of light; something that isn’t possible with conventional lenses. 

Inspired by the butterfly structures, Mark Turner and colleagues (Turner et al., 2011) have used laser beams to ‘write’ these intricate three-dimensional photonic crystals directly into a commercial light-polymerizable ‘photoresist’ material (Figure 8, right). Being somewhat ‘scaled-up’ versions of the natural nanostructures, these had photonic band gaps in the infrared part of the spectrum. Current telecommunications operates mostly at infrared wavelengths, and these structures could find uses there; some, for example, have a corkscrew lattice that make them respond differently to circularly polarized light with a left- or right-handed twist. 

Figure 8

Figure 8. The gyroid phase (left), and structures mimicking the ‘butterfly gyroid’: (middle) a network of titania organized by self-assembly of a block copolymer, and (right) a larger-scale lattice made by setting a light-sensitive polymer with laser beams (scale bar: 10 µm). (Left figure, courtesy of Matthias Weber, Indiana University. Middle figure, from Stefik et al., 2012. Right figure, from Turner et al., 2011)

Photonic Crystal Fibers

The spines of some marine polychaete worms, such as Aphrodita (the sea mouse) and Pherusa, are tubular structures containing hexagonally packed hollow cylindrical channels a few hundred nanometers across and made from chitin. These arrays act as two-dimensional photonic crystals that reflect light strongly in the long-wavelength part of the spectrum, which gives the Aphrodite spine a deep, iridescent red color (Figure 9) (Parker et al., 2001; Trzeciak & Vukusic, 2009). 

Figure 9a
Figure 9b
Figure 9c

Figure 9. The tiny spines of polychaete worms such as the sea mouse (Polychaeta: Aphroditidae; top left) are natural photonic crystals. Seen close up in cross section, they consist of regularly packed hollow channels with walls of chitin. Middle left: cross-section from Pherusa (scale bar: 2 µm); center: side view of channels from Aphrodita; right: the red color of light passing through a spine of Aphrodita. Artificial photonic fibres like this can easily be made by heating and drawing out bundles of glass capillaries (bottom). They can confine light within the ‘solid’ channels even around tight bends. (Note the solid ‘defect’ in the central channel.) (Top, middle center and middle right, courtesy of Andrew Parker, University of Oxford. Middle left, from Trzeciak & Vukusic, 2009. Bottom, from Russell, 2003)

It is not clear if the optical properties of the polychaete spines have any biological function. But there are certainly uses for such light-manipulating fibres in optical technology. For example, Philip Russell and collaborators (Russell, 2003) have made them by stacking glass capillaries into hexagonally packed bundles and drawing them out under heat into narrow fibers laced through with holes. If ‘defects’ are introduced into the array of tubular channels, either by including a wider capillary or a solid rod in the bundle, light can pass along the defect while being excluded from the photonic crystal, creating an optical fiber with a cladding that is essentially impermeable to light of wavelengths within the band gap. Photonic crystal fibers like this can guide light around tighter bends than is usually possible with conventional fibers, where the light is confined less reliably by internal reflection at the fibre surface. As a result, these fibers would work better for guiding light in tightly confined spaces, such as on optical microchips. And because photonic crystal fibers are in general less ‘leaky’ than conventional ones, they could be replace them in optical telecommunications networks, requiring less power, and obviating the need for amplifiers to boost signals sent over long distances.  

Disordered Nanosponges

The splendid blue and green plumage of many birds, while also being physical rather than pigmented colors, lacks the iridescence of the hummingbird or the peacock. Instead, they have the same color viewed from any angle. They scatter light from sponge-like keratin nanostructures; but because these structures are disordered, the scattering is diffuse, like the blue of the sky, rather than mirror-like and iridescent (Dufresne et al., 2009). 

In the blue-and-yellow macaw, Ara ararauna, (Figure 10), and the black-capped kingfisher Halcyon pileata, the empty spaces in the keratin matrix of the feather barbs form tortuous channels about 100 nm wide. A similar random network of filaments in the cuticle of the Cyphochilus beetle gives it a dazzlingly bright white shell. In some other birds, such as the blue-crowned manakin, Lepidothrix coronata, the air holes are instead little spherical bubbles connected by tiny cavities. 

Figure 10a
Figure 10b

Figure 10. The blue feathers of the blue-and-yellow macaw contain sponge-like labyrinths of air and keratin (bottom left), which scatter blue light strongly in all directions. Some other feathers derive similar colors from spherical ‘bubble-like’ air holes in the keratin matrix (bottom right). Scale bars: 500 nm. (Bottom figure, from Dufresne et al., 2009)

It is believed that both of these structures are formed as keratin separates out spontaneously from the fluid cytoplasm of feather-forming cells, like oil from water (Dufresne et al., 2009). In liquid mixtures, such as solidifying molten metal alloys or polymers, such phase separation creates different structures in different conditions. If the mixture is intrinsically unstable, the components separate into disorderly, interwoven channels in a process called spinodal decomposition. But if the mixture is metastable (provisionally stable), like water supersaturated with dissolved gas, then the separating phase will form discrete blobs or bubbles that grow from very tiny ‘seeds’ or nuclei. Prum thinks that either of these processes may happen as bird feathers develop, and that birds have evolved a way of controlling the rate of keratin phase separation so that they can arrest the nanostructure at a certain size. Once the cells have died and dried, this size determines the wavelength of scattered light, and thus the feather’s color. 

This kind of diffuse light-scattering has been used for centuries as a way of making colors in technology. In milk, microscopic droplets of fat with a wide range of sizes cause scattering of all visible wavelengths, and give the liquid its opaque whiteness. Michael Faraday discovered in the nineteenth century that light scattering from nanoscale particles of gold suspended in water can create a deep reddish-purple color with a precise hue that depends on the size of the particles. Glassmakers had been using alchemical recipes to precipitate nanoscale gold particles in molten silica to make ruby glass ever since ancient times. 

Today, engineers are looking at how these random networks and particle arrays can give rise to strongly colored and high-opacity materials. Pete Vukusic and colleagues (Hallam et al., 2009) have mimicked the cuticle of Cyphochilus beetles in random porous networks made from interconnected filaments of the minerals calcium carbonate and titanium dioxide mixed with a polymer and oil liquid binders and left to dry. Guided by the size and density of filaments in the beetle shell, they were able to make thin coatings with brilliant whiteness. Meanwhile Prum, his colleague Eric Dufresne and their coworkers at Yale University (Forster et al., 2010) have mimicked the disordered sponges of bird feathers by creating films of randomly packed microscopic polymer beads, which have blue-green colors (Figure 11). 

Figure 11

Figure 11. This thin film of randomly arrayed polymer microspheres mimics the keratin matrix in the blue feathers of the blue-crowned manakin. (From Forster et al., 2010)

Color Change

One of the most enviable optical tricks in nature is to produce reversible color changes. The reflective, protean colors in the skins of squid such as the Loligidinae family are produced by a protein called reflectin, arranged into plate-like stacks in cells called iridophores, which again act as color-selective reflectors (Figure 12). The color changes are thought to be involved in both camouflage and communication between squid for mating and displays of aggression. 

Figure 12

Figure 12. Stacked plates of the reflectin protein (left) in iridophore cells (center) create tunable reflective colors in squid (right). (Center figure, courtesy of Daniel Morse, University of California at Santa Barbara)

Daniel Morse and colleagues have recently figured out how the color changes of iridophores are achieved (Tao et al., 2010). The reflectin proteins crumple up into nanoparticles, which pack together into dense arrays that make up the flat layers. These layers are sandwiched between deep folds of the cell membrane. The color change can be triggered by neurotransmitter lipid molecules called acetylcholine, which activate a biochemical process that fixes electrically charged phosphate chemical groups onto the reflectin protein. These groups largely neutralize the proteins’ intrinsic charge and allow them to pack more closely together, increasing the reflectivity of the layers. At the same time, this compaction squeezes water from between the protein particles and out of the cell, and enables the reflectin layers to sit closer together. 

Morse and colleagues (Holt et al., 2010) think that it should be possible to copy some of these tricks in optical devices, perhaps even using reflectins themselves. They have inserted the gene encoding a reflectin protein from the long-finned squid Loligo pealeii into Escherichia colibacteria. When expressed, the protein spontaneously collapses into nanoparticles (Tao et al., 2010). The size of these particles can be tuned by controlling the interactions between charged groups on the proteins using salt. Held between stacks of permeable membranes, these materials might therefore swell and contract, altering the reflected wavelengths, in response to chemical triggers. Morse and colleagues have also taken inspiration from reflectins to develop a light switch based on a wholly synthetic light-sensitive polymer. They use an electric field both to change the refractive index of the polymer and to pull salt into the polymer film to swell it. As with iridophores, this combination of effects alters the material’s response to light dramatically, switching it from transparent to opaque; all without moving parts or high-tech manufacturing methods. The team are currently working with Raytheon Vision Systems, an optics company in Goleta, California, to use this system in fast shutters for infrared cameras. 

The Art and Science of Natural Color Mixing

Many of the optical effects found in nature are not purely due to structural colors, but arise from their combination with absorbing pigments (Shawkey et al., 2009). In squid, a thin pigment layer above the reflective layer acts as a filter that can modify the appearance, for example, making it mottled; reflective and absorbing to different degrees in different places. In bird feathers, the physical colors resulting from melanin nanostructures embedded in a keratin protein matrix can be tuned by light-absorbing filters of pigments, such as carotenoids, which absorb red and yellow light. The characteristic green plumage of parrots seems to be produced by laying a yellow pigment over a blue reflective layer of melanin and keratin (Figure 13). And the purple wing tips of Purple Tip butterflies come from red pigments beneath a blue iridescent surface. 

Figure 13

Figure 13. Green is a characteristic color of parrots, but their plumage contains no green pigment, nor is it purely a structural color. Rather, it results from ‘structural blue’ overlaid with a filter of yellow pigment.

Chameleons display perhaps the most advanced mastery of these mixing tricks. Their spectacular color changes are produced by three separate systems for modifying the reflected light, stacked one atop the other. The first layer consists of cells containing red and yellow light-absorbing pigment particles, the location of which within the cell determines the color intensity. Below these are iridophores like those of squid, from which blue and white light may be selectively reflected by crystalline layers of the molecule guanine (also a component of DNA). Finally there is a layer of cells containing the dark pigment melanin, which act like the colored ‘ground’ layers of Old Master paintings to modify the reflection of light that penetrates through the first two layers. This combination of reflection and absorption enables the chameleon to adapt its skin color across a wide, albeit species-specific, range to signal warning, for mating displays, and for camouflage (Forbes, 2009). 

How pigments alter and adjust the reflected light in such cases is still imperfectly understood. One problem is that the combinations are so diverse; more than 20 different arrangements of melanin, keratin and air have been identified in the plumage of birds. Moreover, melanin is itself a light absorber, creating colors ranging from yellow to black. The bright white markings on the blue wings of the Morpho cypris butterfly are produced by simply removing the melanin from reflective multilayer structures; the mirrors remain, but the pigments do not. 

In such ways, evolution has made creative use of the limited range of materials at its disposal to generate a riot of profuse coloration and markings. A better understanding of how this is achieved could give painters and visual artists access to entirely new ways of making colors based on iridescent and pearlescent pigments, whose use has so far been largely restricted to less sophisticated applications in the automobile and cosmetic industries (Schenk & Parker, 2011). 

Painter Franziska Schenk has been exploring the mixing of structural and pigmented color during her stay as artist-in-residence in the Department of Biosciences at the University of Birmingham in the UK (Schenk, 2009). With iridescent particles, says Schenk, “the established methods of easel painting no longer apply. Their conversion to painting requires something truly innovative.” 

Schenk used iridescent particles to reproduce the starting blue of the Morpho wing in a series of paintings that change color when lit or viewed from different angles (Figure 14). The background color on which the particles are placed is central to the effect. On white, the light not reflected from the blue particles passes through and bounces off the base. This means that when not seen face-on, the blue quickly fades and is replaced by a muted yellow. But on a black background, all non-blue light is absorbed, and the blue is more pure and intense. 

Figure 14

Figure 14. Painting of a Morpho butterfly wing by Franziska Schenk, using blue pearlescent pigments. The color changes depending on the angle of illumination, as well as on the nature of the background color. (Courtesy of Franziska Schenk)

Although the brilliance of these colors doesn’t approach that of butterfly wings, it takes advantage of recent improvements in synthetic pearlescent particles. The first of these were made by coating mica flakes with multilayers of metal oxides to generate the diffraction grating. But because the mica surfaces were not perfectly smooth and the grain sizes varied, there was always a range in the precise colors and intensities of the particles. Schenk has used pigments in which the mica substrate is replaced by a transparent borosilicate glass, which is smoother and gives a purer hue. She believes that “iridescent technology is destined to introduce a previously unimaginable level of intensity and depth, thus adding beauty, luster and a dynamic dimension to art”. Schenk’s Studies of Cuttlefish (Figure 15) is a painting that uses iridescent flakes mixed with beads and wax. 

Figure 15

Figure 15. “Studies of Cuttlefish” by Franziska Schenk, using iridescent flakes mixed with beads and wax. (Courtesy of Franziska Schenk)

Another series of cuttlefish, “Mantle of Many Colours” (Figure 16), was made with iridescent paint that differs in appearance depending on the conditions and angle of lighting, which results in a compelling chameleon effect that traditional paints simply cannot create. The colors change from greens to purples as the viewing angle shifts. “Still images, together with any attempt to verbally describe the effect, are pretty limiting”, Schenk admits; you have to see these things in the flesh to appreciate their full impact. 

Figure 16

Figure 16. “Mantle of Many Colours” by Franziska Schenk, which uses iridescent paint, as seen from different angles. (Courtesy of Franziska Schenk)

Conclusion

“Every day you play with the light of the universe”, wrote the Chilean poet Pablo Neruda, but he had no idea how literally true this would become. Our technologies for transmitting, manipulating and displaying information, whether for work or play, depend increasingly on our ability to control light; to harness and transform color. Some of nature’s most stunning sights depend on such a facility too, and often they show us that beauty can be inextricably linked to utility. We are impressed by plumage, by markings and animal displays, that are specifically designed by evolution to make such an impression. And nature has found ways to make this chromatic exuberance robust, changeable, responsive, and cheap and reliable to manufacture. In shaping color without the chemical contingency of pigments, there seems to be little we can dream up that nature has not already anticipated, exploiting its capacity to fashion intricate fabrics and structures on the tiniest scales. We can only learn, and admire. 

References

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05/30/12 

Technology of Nanostructures

Colloidal Self Assembly for fabrication of Photonic nanostructures including

  • Colloidal crystals
  • Composite and Inverse Opals
  • Photonic Glasses

Applications

  • Displays
  • Optical Devices
  • Photochemistry
  • Biological Sensors

Source: Self-assembled colloidal structures for photonics

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(73) Assignee:SNUR&DBFoundation,Seoul(KR)

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NATURE | VOL 396 | 5 NOVEMBER 1998

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Structural color

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https://manoharan.seas.harvard.edu/structural-color

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https://pubmed.ncbi.nlm.nih.gov/16015669/

Mechanisms of structural colour in the Morpho butterfly: cooperation of regularity and irregularity in an iridescent scale.

Shuichi KinoshitaShinya Yoshioka, and  Kenji Kawagoe

Proc Biol Sci. 2002 Jul 22;269(1499):1417-21.

https://pubmed.ncbi.nlm.nih.gov/12137569/

Structural Colours in Feathers

Nature volume 112, page243(1923)

https://www.nature.com/articles/112243a0


Angle-independent Structural Coloured Materials inspired by Blue Feather Barbs

Yukikazu TAKEOKA
NIPPON GOMU KYOKAISHI (2014)

Stimuli-responsive opals: colloidal crystals and colloidal amorphous arrays for use in functional structurally colored materials

Yukikazu Takeoka
Journal of Materials Chemistry C (2013)

Angle-independent structural coloured amorphous arrays

Yukikazu Takeoka
Journal of Materials Chemistry (2012)

Full-Spectrum Photonic Pigments with Non-iridescent Structural Colors through Colloidal Assembly

Jin-Gyu Park, Shin-Hyun Kim, Sofia Magkiriadou, Tae Min Choi, Young-Seok Kim, Vinothan N. Manoharan*

Angewandte Chemie International Edition 53(11): 2899 (2014)

https://dash.harvard.edu/bitstream/handle/1/24873725/submitted_version-postprint.pdf?sequence=1

Amorphous Photonic Structures with Brilliant and Noniridescent Colors via Polymer-Assisted Colloidal Assembly

Yang Hu, Dongpeng Yang,* and Shaoming Huang*

ACS Omega 2019, 4, 18771−18779

https://pubs.acs.org/doi/pdf/10.1021/acsomega.9b02734

Viburnum tinus Fruits Use Lipids to Produce Metallic Blue Structural Color

Rox Middleton,1,8,10 Miranda Sinnott-Armstrong,2,9,10 Yu Ogawa,3 Gianni Jacucci,1 Edwige Moyroud,4,5 Paula J. Rudall,6 Chrissie Prychid,6 Maria Conejero,6 Beverley J. Glover,7 Michael J. Donoghue,2 and Silvia Vignolini

In-Plane Direct-Write Assembly of Iridescent Colloidal Crystals

Alvin T. L. Tan, Sara Nagelberg, Elizabeth Chang-Davidson, Joel Tan, Joel K. W. Yang, Mathias Kolle, and A. John Hart

Fabrication of non-iridescent structural color on silk surface by rapid T polymerization of dopamine

Xiaowei Zhu, Biaobiao Yan, Xiaojie Yan, Tianchen Wei, Hongli Yao, Md Shipan Mia, Tieling Xing*, Guoqiang Chen

Bioinspired Stimuli-Responsive Color-Changing Systems

Golnaz Isapour and Marco Lattuada

Advanced Materials 30(19): 1707069

Plasmonic films based on colloidal lithography

Bin Ai a, Ye Yu a, Helmuth Möhwald b, Gang Zhang a,⁎, Bai Yang

Advances in Colloid and Interface Science

Printing a Wide Gamut of Saturated Structural Colors Using Binary Mixtures, With Applications in Anti-Counterfeiting

March 2020

ACS Applied Materials & Interfaces 

https://www.researchgate.net/publication/340326621_Printing_a_Wide_Gamut_of_Saturated_Structural_Colors_Using_Binary_Mixtures_With_Applications_in_Anti-Counterfeiting

Template Synthesis for Stimuli-Responsive Angle Independent Structural Colored Smart Materials

Mohammad Harun-Ur-Rashid1, Abu Bin Imran1, Takahiro Seki1, Yukikazu Takeoka1*, Masahiko Ishii2 and Hiroshi Nakamura2

https://www.jstage.jst.go.jp/article/tmrsj/34/2/34_333/_pdf

Optical Characterization of the Photonic Ball as a Structurally Colored Pigment

Ryosuke Ohnuki,* Miki Sakai, Yukikazu Takeoka, and Shinya Yoshioka

2020

HIGHLY DIFFRACTING, COLORSHIFTING, POLYMERIZED CRYSTALLINE COLLODAL ARRAYS OF HIGHILY CHARGED POLYMER SPHERES, PAINTS AND COATINGS AND PROCESSES FOR MAKING THE SAME

Matti Ben-Moshe, Reut(IL);

Sanford A. Asher, Pitsburgh, PA(US);

Justin J.Bohn, Pitsburgh, PA(US)

US7,902,272B2 /2011

Structural colors: from natural to artificial systems

Yulan Fu,1 Cary A. Tippets,2 Eugenii U. Donev3 and Rene Lopez

WIREs Nanomed Nanobiotechnol 2016

Structural color and its interaction with other color-producing elements: perspectives from spiders

Bor-Kai Hsiung*, Todd A Blackledge, and Matthew D Shawkey
Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, Ohio

Self-assembled colloidal structures for photonics

Shin-Hyun Kim1, Su Yeon Lee2, Seung-Man Yang2* and Gi-Ra Yi3*

Harvard University, USA, KAIST and Chungbuk National University, Korea

Chameleon-Inspired Strain-Accommodating Smart Skin

Yixiao Dong,† Alisina Bazrafshan,† Anastassia Pokutta,‡ Fatiesa Sulejmani,‡ Wei Sun,‡ J. Dale Combs,† Kimberly C. Clarke,† and Khalid Salaita

ACS Nano XXXX, XXX, XXX−XXX

A composite hydrogels-based photonic crystal multi-sensor

Cheng Chen1, Zhigang Zhu1, Xiangrong Zhu1, Wei Yu1, Mingju Liu1, Qiaoqiao Ge1 and Wei-Heng Shih2

Published 16 April 2015 • 
Materials Research ExpressVolume 2Number 4

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Template Synthesis for Stimuli-Responsive Angle Independent Structural Colored Smart Materials

Article in Transactions of the Materials Research Society of Japan

February 2009

PATTERNED SILK INVERSE OPAL PHOTONIC CRYSTALS WITH TUNABLE, GEOMETRICALLY DEFINED STRUCTURAL COLOR

US Patent US2019/018731A1

Fiorenzo G.Omenetto, Lexington,MA (US);

YuWang, Medford, MA (US)

Bioinspired colloidal materials with special optical, mechanical, and cell-mimetic functions

Taiji Zhang, Yurong Ma and Limin Qi*

J. Mater. Chem. B, 2013, 1, 251

DYNAMICALLY TUNABLE PLASMONIC STRUCTURAL COLOR

DANIEL FRANKLIN

PhD Thesis 2018

Wetting in Color: Colorimetric Differentiation of Organic Liquids with High Selectivity

Ian B. Burgess,†,* Natalie Koay,‡,§, Kevin P. Raymond,‡,§, Mathias Kolle,† Marko Loncar,† and Joanna Aizenberg†,‡,^,*

Biologically inspired LED lens from cuticular nanostructures of firefly lantern

Jae-Jun Kima, Youngseop Leea, Ha Gon Kimb, Ki-Ju Choic, Hee-Seok Kweonc, Seongchong Parkd, and Ki-Hun Jeong

PNAS | November 13, 2012 | vol. 109 | no. 46

Functional Micro–Nano Structure with Variable Colour: Applications for Anti-Counterfeiting

Hailu Liu , Dong Xie, Huayan Shen, Fayong Li, and Junjia Chen

Hindawi
Advances in Polymer Technology
Volume 2019, Article ID 6519018, 26 pages

REVIEW ARTICLE
515 million years of structural colour

Andrew Richard Parker

J. Opt. A: Pure Appl. Opt. (2000) R15–R28

Colloidal Crystals from Microfluidics

Feika Bian, Lingyu Sun, Lijun Cai, Yu Wang, Yuetong Wang, and Yuanjin Zhao

Small 2019, 1903931

Nanochemistry Chapter 1

Mimicking the colourful wing scale structure of the Papilio blumei butterfly

Mathias Kolle1,2, Pedro M. Salgard-Cunha1, Maik R. J. Scherer1, Fumin Huang1, Pete Vukusic3, Sumeet Mahajan1, Jeremy J. Baumberg1 & Ullrich Steiner

Cambridge Univ

Nature Nanotechnology, 2010, (5) 511-515

Bioinspired bright noniridescent photonic melanin supraballs

Ming Xiao,1* Ziying Hu,2,3* Zhao Wang,4 Yiwen Li,5 Alejandro Diaz Tormo,6 Nicolas Le Thomas,6 Boxiang Wang,7 Nathan C. Gianneschi,2,3,4† Matthew D. Shawkey,8,9† Ali Dhinojwala

Sci. Adv. 2017;3:e1701151 15 September 2017

Structural Color and Odors: Towards a Photonic Crystal Nose Platform

Leonardo da Silva Bonifacio

PhD Thesis 2010

The Self-Assembly of Cellulose Nanocrystals: Hierarchical Design of Visual Appearance

Richard M. Parker, Giulia Guidetti, Cyan A. Williams, Tianheng Zhao, Aurimas Narkevicius, Silvia Vignolini,* and Bruno Frka-Petesic

Adv. Mater. 201830, 1704477

https://onlinelibrary.wiley.com/doi/pdf/10.1002/adma.201704477

Bio-inspired design of multiscale structures for function integration

Kesong Liua, Lei Jiang

A ROBUST SMART FILM :REVERSIBLY SWITCHING FROM HIGH TRANSPARENCY TO ANGLE-INDEPENDENT STRUCTURAL COLOR DISPLAY

US Patent 2018

US2018/024876A1

Inventors:Shu YANG, BlueBel, PA(US);

Deng teng GE, Shanzhai(CN);

Elaine LEE,Brooklyn,NY (US)

Click to access US20180244876A1.pdf

Optimization of sharp and viewing-angle-independent structural color

Chia Wei Hsu,1,2,∗ Owen D. Miller,3 Steven G. Johnson,3 and Marin Soljacˇic ́1

Bioinspired living structural color hydrogels

Fanfan Fu, Luoran Shang, Zhuoyue Chen, Yunru Yu, Yuanjin Zhao

SCIENCE ROBOTICS

Measuring and specifying goniochromatic colors

Alejandro Ferrero1, Joaquín Campos1, Esther Perales2, Ana M. Rabal1, Francisco Martínez-Verdú2, Alicia Pons1, Elisabet Chorro2 and M. Luisa Hernanz

Bio-Inspired Photonic Structures: Prototypes, Fabrications and Devices

By Feng Liu, Biqin Dong and Xiaohan Liu

Submitted: November 5th 2011Reviewed: May 28th 2012Published: September 19th 2012

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Photobiology

The Science of Light and Life
  • Lars Olof Björn

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“Guanigma”: The Revised Structure of Biogenic Anhydrous Guanine 

Anna Hirsch,† Dvir Gur,‡ Iryna Polishchuk,§ Davide Levy,§ Boaz Pokroy,§ Aurora J. Cruz-Cabeza,∥ Lia Addadi,*,‡ Leeor Kronik,*,† and Leslie Leiserowitz*,†

Natural photonics 

Pate Vukusic

Stimuli-Responsive Structurally Colored Films from Bioinspired Synthetic Melanin Nanoparticles

Ming Xiao,†,# Yiwen Li,‡,#,○ Jiuzhou Zhao,† Zhao Wang,‡ Min Gao,§ Nathan C. Gianneschi,*,‡ Ali Dhinojwala,*,† and Matthew D. Shawkey

Chem. Mater. 2016, 28, 5516−5521

A Microfluidic Chip with Integrated Colloidal Crystal for Online Optical Analysis

Siew-Kit Hoi, Xiao Chen, Vanga Sudheer Kumar, Sureerat Homhuan, Chorng-Haur Sow, and Andrew A. Bettiol*

Highly monodisperse zwitterion functionalized non-spherical polymer particles with tunable iridescence

Vivek Arjunan Vasantha*aWendy RusliaChen JunhuiaZhao WenguangaKandammathe Valiyaveedu SreekanthbcRanjan Singhbc and Anbanandam Parthiban*a 

 RSC Adv., 2019, 9, 27199-27207

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Stimuli-responsive opals: colloidal crystals and colloidal amorphous arrays for use in functional structurally colored materials

Yukikazu Takeoka

J. Mater. Chem. C, 2013, 1, 6059

Biomimetic and Bioinspired Photonic Structures

Wu Yi, Ding-Bang Xiong * and Di Zhang

Nano Adv., 2016, 1, 62–70.

Bio-inspired photonic crystal patterns

Pingping Wu,abJingxia Wang *abc  and  Lei Jiang

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Stretchable and reflective displays: materials, technologies and strategies

Nano Convergence volume 6, Article number: 21 (2019)

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Colloidal Lithography

By Ye Yu and Gang Zhang

2013

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Structure and mechanical properties of beetle wings: a review 

Jiyu Sun and Bharat Bhushan

RSC Advances, 2012, 2, 12606–12623

A highly conspicuous mineralized composite photonic architecture in the translucent shell of the blue-rayed limpet

Ling LiStefan KolleJames C. WeaverChristine OrtizJoanna Aizenberg & Mathias Kolle 

Nature Communications volume 6, Article number: 6322 (2015) 

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Fabrication of 3D polymeric photonic arrays and related applications 

A. Yadav a, *, A. Kaushik b, Y. Mishra c, V. Agrawal d, A. Ahmadivan e, K. Maliutina f, Y. Liu g, Z. Ouyang h, W. Dong a, **, G.J. Cheng

Materials Today Chemistry, https://doi.org/10.1016/j.mtchem.2019.100208

Reversible Design of Dynamic Assemblies at Small Scales

Fernando Soto, Jie Wang, Shreya Deshmukh, and Utkan Demirci

Adv. Intell. Syst. 2020, 2000193

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Biological composites— complex structures for functional diversity.

Eder, M., Shahrouz, A., & Fratzl, P. (2018).

Science, 362(6414), 543-547.

Stimuli-Responsive Optical Nanomaterials

Zhiwei Li, and Yadong Yin

https://onlinelibrary.wiley.com/doi/am-pdf/10.1002/adma.201807061

Bio-Inspired Structural Colors Produced via Self-Assembly of Synthetic Melanin Nanoparticles

Ming Xiao,†,^ Yiwen Li,‡,^ Michael C. Allen,§ Dimitri D. Deheyn,§ Xiujun Yue,‡ Jiuzhou Zhao,† Nathan C. Gianneschi,*,‡ Matthew D. Shawkey,*, and Ali Dhinojwala

ACS Nano 2015

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Pigments Based on Colloidal Photonic Crystals

Carlos Israel Aguirre Vélez

PhD Thesis 2010

Structural Colors in Nature: The Role of Regularity and Irregularity in the Structure

Shuichi Kinoshita* and Shinya Yoshioka

ChemPhysChem 2005, 6, 1442 – 1459

Flexible mechanochromic photonic crystals: routes to visual sensors and their mechanical properties

Rui Zhang, Qing Wang  and Xu Zheng

J. Mater. Chem. C, 2018, 6, 3182

Designing visual appearance using a structured surface

VILLADS EGEDE JOHANSEN,1,* LASSE HØJLUND THAMDRUP,2 KRISTIAN SMISTRUP,2 THEODOR NIELSEN,2 OLE SIGMUND,1 AND PETER VUKUSIC

Vol. 2, No. 3 / March 2015 / Optica

Subwavelength nanocavity for flexible structural transmissive color generation with a wide viewing angle

KYU-TAE LEE,1 JI-YUN JANG,2 SANG JIN PARK,2 UJWAL KUMAR THAKUR,2 CHENGANG JI,1 L. JAY GUO,1 AND HUI JOON PARK

Vol. 3, No. 12 / December 2016 / Optica

Color and Texture Morphing with Colloids on Multilayered Surfaces

Ziguang Chen,†,‡,⊥ Shumin Li,†,‡,⊥ Andrew Arkebauer,§ George Gogos,† and Li Tan

ACS Appl. Mater. Interfaces 2015, 7, 10125−10131

https://pubs.acs.org/doi/pdf/10.1021/am5087215

Electrodeposition of Large Area, Angle-Insensitive Multilayered Structural Colors

Chengang Ji,1,† Saurabh Acharya,1,† Kaito Yamada,2 Stephen Maldonado,2,3,* and L. Jay Guo

https://par.nsf.gov/servlets/purl/10111165

Bright and Vivid Diffractive-Plasmonic Structural Colors

Emerson G. Melo,†,‡,§ Ana L. A. Ribeiro,†,‡ Rodrigo S. Benevides,†,‡ Antonio A. G. V. Zuben,†,‡ Marcos V. P. Santos,† Alexandre A. Silva,¶ Gustavo S. Wiederhecker,†,‡ and Thiago P. M. Alegre

2019

Biomimetic photonic structures for optical sensing

Raúl J. Martín-Palmaa, Mathias Kolle

Optics and Laser Technology 109

2019

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Colloidal Self-Assembly Concepts for Plasmonic Metasurfaces

Martin Mayer, Max J. Schnepf, Tobias A. F. König,* and Andreas Fery

Adv. Optical Mater. 20197, 1800564

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Flourishing Smart Flexible Membranes Beyond Paper

Anal. Chem. 2019, 91, 7, 4224–4234

Publication Date:March 18, 2019

https://doi.org/10.1021/acs.analchem.9b00743

https://pubs.acs.org/doi/full/10.1021/acs.analchem.9b00743

Biological vs. Electronic Adaptive Coloration: How Can One Inform the Other?

Eric Kreit1, Lydia M. Mäthger2, Roger T. Hanlon2, Patrick B. Dennis3, Rajesh R. Naik3, Eric Forsythe4 and Jason Heikenfeld1*

Dynamic plasmonic color generation enabled by functional materials

  1. Frank Neubrech
  2. Xiaoyang Duan
  3. Na Liu

Science Advances  04 Sep 2020:
Vol. 6, no. 36, eabc2709
DOI: 10.1126/sciadv.abc2709

https://advances.sciencemag.org/content/6/36/eabc2709

The New Generation of Physical Effect Colorants

Faiz Rahman and Nigel P. Johnson

Optics and Photonics News

2008

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The Japanese jewel beetle: a painter’s challenge

Franziska Schenk1, Bodo D Wiltsand Doekele G Stavenga2

Bioinspir. Biomim. (2013) 045002 (10pp)

Gold bugs and beyond: a review of iridescence and structural colour mechanisms in beetles (Coleoptera)

Ainsley E. Seago1,*, Parrish Brady2, Jean-Pol Vigneron3 and Tom D. Schultz4

Iridescence as Camouflage

Karin Kjernsmo,1,4,* Heather M. Whitney,1 Nicholas E. Scott-Samuel,2 Joanna R. Hall,2 Henry Knowles,1 Laszlo Talas,2,3 and Innes C. Cuthill1

Current Biology

VOLUME 30, ISSUE 3, P551-555.E3, FEBRUARY 03, 2020

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Chromic Phenomena: Technological Applications of Colour Chemistry

Peter Bamfield

Book, Royal Society of Chemistry 2018 edition

Amorphous diamond-structured photonic crystal in the feather barbs of the scarlet macaw

Haiwei Yina,1, Biqin Donga,1, Xiaohan Liua, Tianrong Zhana, Lei Shia, Jian Zia,2, and Eli Yablonovitchb,2

PNAS | July 24, 2012 | vol. 109 | no. 30

Amorphous Photonic Crystals with Only Short-Range Order

Lei Shi, Yafeng Zhang, Biqin Dong, Tianrong Zhan, Xiaohan Liu,* and Jian Zi

Adv. Mater. 201325, 5314–5320

Diamond-structured photonic crystals

Nature Materials  volume 3, pages593–600(2004)

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Nano-Optics in the Biological World: Beetles, Butterflies, Birds, and Moths

Mohan Srinivasarao*

Fiber and Polymer Science Program, North Carolina State University, Raleigh, North Carolina 27695-8301

Chem. Rev. 1999, 99, 1935−1961

515 million years of structural colour

Andrew Richard Parker

Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK

E-mail: andrew.parker@zoo.ox.ac.uk

J. Opt. A: Pure Appl. Opt. (2000) R15–R28

Photophysics of Structural Color in the Morpho Butterflies

Shuichi KINOSHITA1,2*, Shinya YOSHIOKA1,2, Yasuhiro FUJII2 and Naoko OKAMOTO

Forma17, 103–121, 2002

Photonic structures in biology

  • October 2004

Peter Vukusic

https://www.researchgate.net/publication/235888153_Photonic_structures_in_biology

Physics of structural colors

S Kinoshita, S Yoshioka and J Miyazaki

Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan

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Rep. Prog. Phys. 71 (2008) 076401 (30pp)

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Coloration strategies in peacock feathers

Jian Zi*, Xindi Yu, Yizhou Li, Xinhua Hu, Chun Xu, Xingjun Wang, Xiaohan Liu*, and Rongtang Fu

A Review of Electronic Paper Display Technologies from the Standpoint of SID Symposium Digests

Tatsumi Takahashi

Review of Paper-Like Display Technologies

Peng Fei Bai1, Robert A. Hayes1, Ming Liang Jin1, Ling Ling Shui1, Zi Chuan Yi1, L. Wang1, Xiao Zhang1, and Guo Fu Zhou1, 2

Progress In Electromagnetics Research, Vol. 147, 95–116, 2014

Stretchable and reflective displays: materials, technologies and strategies

Nano Convergence volume 6, Article number: 21 (2019)

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Review Paper: A critical review of the present and future prospects for electronic paper

Jason Heikenfeld (SID Senior Member) Paul Drzaic (SID Fellow)
Jong-Souk Yeo (SID Member)
Tim Koch (SID Member)

Journal of the SID 19/2, 2011

Biological versus electronic adaptive coloration: how can one inform the other?

Eric Kreit1, Lydia M. Ma ̈thger2, Roger T. Hanlon2, Patrick B. Dennis3, Rajesh R. Naik3, Eric Forsythe4 and Jason Heikenfeld1

J R Soc Interface 10: 20120601.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsif.2012.0601

Transmissive/Reflective Structural Color Filters: Theory and Applications


Yan Yu,1,2 Long Wen,2 Shichao Song,2 and Qin Chen

Volume 2014 |Article ID 212637 | https://doi.org/10.1155/2014/212637

https://www.hindawi.com/journals/jnm/2014/212637/

Interferometric modulator display

https://en.wikipedia.org/wiki/Interferometric_modulator_display

Qualcomm resurrects Mirasol reflective displays with new 576 ppi smartphone panel

https://www.theverge.com/2013/5/22/4354642/high-res-mirasol-display-for-smartphones-demonstrated

Iridescence-controlled and flexibly tunable retroreflective structural color film for smart displays

  • Wen Fan
  • Jing Zeng
  • Qiaoqiang Gan
  • Dengxin Ji
  • Haomin Song
  • Wenzhe Liu
  • Lei Shi
  • Limin Wu

Science Advances  09 Aug 2019:
Vol. 5, no. 8, eaaw8755
DOI: 10.1126/sciadv.aaw8755

Click to access eaaw8755.full.pdf

Artificial Structural Color Pixels: A Review 

by Yuqian Zhao 1Yong Zhao 1,*Sheng Hu 1Jiangtao Lv 1Yu Ying 2Gediminas Gervinskas 3 and Guangyuan Si 

Materials 201710(8), 944; https://doi.org/10.3390/ma10080944

https://www.mdpi.com/1996-1944/10/8/944/htm

Dynamically Tunable Plasmonic Structural Color

Daniel Franklin
University of Central Florida 2018

PHD Thesis

Colors with plasmonic nanostructures: A full-spectrum review 

Applied Physics Reviews 6, 041308 (2019); https://doi.org/10.1063/1.5110051

https://aip.scitation.org/doi/abs/10.1063/1.5110051?journalCode=are

Dynamic plasmonic color generation enabled by functional materials

Frank Neubrech1,2, Xiaoyang Duan1,2, Na Liu3,4*

Bright and Vivid Diffractive–Plasmonic Reflective Filters for Color Generation

  • Emerson G. Melo, 
  • Ana L. A. Ribeiro, 
  • Rodrigo S. Benevides, 
  • Antonio A. G. V. Zuben, 
  • Marcos V. Puydinger dos Santos, 
  • Alexandre A. Silva, 
  • Gustavo S. Wiederhecker, and 
  • Thiago P. M. Alegre*

ACS Appl. Nano Mater. 2020, 3, 2, 1111–1117Publication Date:December 31, 2019 https://doi.org/10.1021/acsanm.9b02508

https://pubs.acs.org/doi/full/10.1021/acsanm.9b02508

Active control of plasmonic colors: emerging display technologies

Kunli Xiong, Daniel Tordera, Magnus Jonsson and Andreas B. Dahlin

Rep Prog Phys. 2019 Feb;82(2):024501.

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Self-assembled plasmonics for angle-independent structural color displays with actively addressed black states

Daniel Franklina,b, Ziqian Hec, Pamela Mastranzo Ortegab, Alireza Safaeia,b, Pablo Cencillo-Abadb, Shin-Tson Wuc, and Debashis Chandaa,b,c,1

https://www.pnas.org/content/117/24/13350

Bio-inspired intelligent structural color materials

Luoran Shang, Weixia Zhang, Ke Xuc and Yuanjin Zhao

Mater. Horiz., 2019,6, 945-958 

https://pubs.rsc.org/en/content/articlelanding/2019/mh/c9mh00101h#!divAbstract

Advanced Plasmonic Materials for Dynamic Color Display

DOI: 10.1002/adma.201704338

https://www.researchgate.net/publication/320997060_Advanced_Plasmonic_Materials_for_Dynamic_Color_Display

Polarization-independent actively tunable colour generation on imprinted plasmonic surfaces

Nature Communications volume 6, Article number: 7337 (2015)

https://www.nature.com/articles/ncomms8337

Tunable plasmonic color filter 

Rosanna Mastria, Karl Jonas Riisnaes, Monica Craciun, and Saverio Russo

Frontiers in Optics / Laser Science OSA Technical Digest (Optical Society of America, 2020),paper JTh4B.7•

https://doi.org/10.1364/FIO.2020.JTh4B.7

https://www.osapublishing.org/abstract.cfm?uri=FiO-2020-JTh4B.7

Color Change: In Biology and Smart Pigments Technology

  • Color change due to Pigment
  • Color change due to Structure

This post is on color change due to pigments.

In a future post, I will research structural colors.

Key Words

  • Color Change in Biology
  • Color Change using Technology
  • Smart Pigments
  • Thermochromic property
  • Photochromic property
  • Piezochromic property
  • Solvatochromic property
  • Chimiochromic property
  • Electrochromism
  • Smart Textiles
  • Smart Plastics
  • Smart Paper
  • Smart Inks
  • Smart Food Packaging
  • Color Science
  • Material Science
  • Color Fading
  • Color Fastness
  • Color Metamerism
  • Chromatophores
  • Iridophores
  • Leucophores
  • Chlorophyll
  • Anthrocyanins
  • Flavonols
  • Flavonoids

Color Change and Technology

Chromic phenomena in dyes and pigments

Some of the major companies are

  • LCR Hallcrest LLC
  • Hali Pigment Co. Ltd
  • Chromatic Technologies Inc.
  • QCR Solutions Corp.
  • OliKrom
  • SFXC
  • MICI
  • RPM International Inc.
  • Good Life Innovations Ltd
  • FX Pigments Pvt. Ltd
  • Smarol Industry Co. Ltd
  • Kolortek Co. Ltd
  • Kolorjet Chemicals Pvt. Ltd
  • Colourchange

Source: OliKrom

Smart Hybrid Pigments

The solutions developed by OliKrom involve a new generation of hybrid pigments that combines the proven strength of the metal ions and the flexibility of the molecular material. The change in the structure allow to control the color change as a function of :

  • Temperature (thermochromic property),
  • Light (photochromic property),
  • Pressure (piezochromic property),
  • A solvent (solvatochromic property),
  • A gas (chimiochromic property),

The expertise of OliKrom allows for each of these properties:

  • To adjust the request colors,
  • To obtain reversible and/or irreversible color-shifting,
  • To modulate the speed of the color change,
  • To control the issues of fatigability.
  • To insert these adaptive pigments in a formulation (paint, ink, masterbatch, …) without altering the properties!
  • To produce on an industrial scale paintings, inks, master batches, …

Applications

SAFETY
  • Threshold temperature indicators / industrial pipes, thermal mapping.
  • Display: visual aid in the detection of ice.
  • Indicator of “health matter”, gauge effort, shock detection (Aeronautic & Navy).
  • Control: Temperature Indicator for monitoring sensitive products: cold chain, transport & medical vaccines or blood products.
  • Sterilization indicator: labels or inks.
  • Adhesives: indicator of adhesion, optimum drying.
  • Food Packaging: temperature indicator for the consumption of a product: beer, wine, vodka, champagne, cans and bottles, hot and cold drinks, baby food.
TRACEABILITY / INFRINGEMENT
  • Irreversible overheat indicator of industrial processes.
  • Security inks: offset ink for ticketing, games, secure access badges.
  • Infringement Indicator: branded article, banknote.
DECORATION / MARKETING / ADVERTISING
  • Plastic toys: decor with changing color, labels, packaging, paper / plastic promotional, “dynamic” advertising inserts.
  • Cosmetics: Bottles & Jars of cosmetic or perfume.
  • Smart Textiles: comfort indicator, clarification of the textile with temperature.

Fluorescent Pigments and Phosphorescent Pigments

Source: PHOTOLUMINESCENTS: FLUORESCENT AND PHOSPHORESCENT INKS AND PAINTS / OliKrom

Photochromic Pigments

Piezochromic Pigments

Thermochromic

Type

  • Reversible Thermochromic Material
  • Irreversible Thermochromic Material

Material

  • Liquid Crystal
  • Leuco Dyes
  • Pigment
  • Other Materials

Application

  • Roof Coatings
  • Printing
  • Food Packaging
  • Cosmetics
  • Other Applications

Solvachromes and Chemochromes

Color Change in Biology

Animals
  • Chameleon
  • Golden Tortoise Beetle
  • Mimic Octopus
  • Pacific Tree Frog
  • Sea Horses
  • Flounders
  • Cuttlefish
  • Crab Spiders
  • Squid
  • Cyanea Octopus

Mechanisms for Color Change

  • Chromatophores
  • Leucophores
  • Iridophores

Source: Adaptive camouflage helps blend into the environment 

Cephalopods such as cuttlefish often use use adaptive camouflage to blend in with their surroundings. They are able to match colors and surface textures of their surrounding environments by adjusting the pigment and iridescence of their skin.

On the skin surface, chromatophores (tiny sacs filled with red, yellow, or brown pigment) ab­sorb light of various wavelengths. Once vis­ual input is processed, the cephalopod sends a signal to a nerve fiber, which is connected to a muscle. That muscle relaxes and contracts to change the size and shape of the chromato­phore. Each color chromatophore is controlled by a different nerve, and when the attached muscle contracts, it flattens and stretches the pigment sack outward, expanding the color on the skin. When that muscle relaxes, the chro­matophore closes back up, and the color dis­appears. As many as two hundred of these may fill a patch of skin the size of a pencil eraser, like a shimmering pixel display.

The innermost layer of skin, composed of leuc­ophores, reflects ambient light. These broadband light reflectors give the cephalopods a ‘base coat’ that helps them match their surroundings.

Between the colorful chromatophores and the light-scattering leucophores is a reflective lay­er of skin made up of iridophores. These reflect light to create pink, yellow, green, blue, or silver coloration, while the reflector cells (found only in octopuses) reflect blue or green.

Source: https://www.worldatlas.com/articles/10-animals-that-can-change-colors.html

10 Animals That Can Change Colors

The mimic octopus changes their skin tone and body shape to copy other sea creatures.
The mimic octopus changes their skin tone and body shape to copy other sea creatures. 

There are a few animals that have the unique ability to change colors. The ability to change colors can help animals protect themselves against their predators because it allows them to blend into their natural environment. Here is a list of 10 color changing animals.

10. Chameleon

A chameleon is a unique species of lizard famous for changing its skin color. It does so to camouflage with its surrounding. Sometimes chameleons change their color when they are angry or fearful. To change its color, the chameleon adjusts a layer of specialized cells underlying its skin. Others change color in response to humidity, light, and temperature. Chameleons never stop growing. They keep shedding their skin from time to time. Furthermore, chameleons have excellent eyesight characterized by a 360-degree arc vision. Although chameleons do not hear, their bodies detect sound within the surrounding.

9. Golden Tortoise Beetle

The golden tortoise beetle is an insect that can change its color. The species with this ability include Charidotella sexpunctata and Charidotella egregia. The tortoise beetles change color due to particular events that occur in their environment. Such events include meeting a willing mate and being touched by a curious human being. Hence, when they are mating or agitated, the tortoise beetles change their color from gold to a bright red color. The change of color occurs due to a process referred to as optical illusion.

8. Mimic Octopus

Mimic octopus, scientifically known as Thaumoctopus mimicus, change their color and they can also mimic other sea creatures such as a lionfish, jellyfish, stingrays, and sea snakes. The mimic octopus can pick the color of the sea creature that they intend to mimic. The mimic octopuses change their body shape to avoid potential predators. The change of skin color helps them to adapt to their surrounding. Mimic octopuses can change color and mimic shapes due to their skin which is very responsive to the environment.

7. Pacific Tree Frog

The Pacific Tree Frog inhabits North America. One of its common features is the sticky toe pads. The sticky toe pads enable them to climb trees and plants. The Pacific Tree Frog changes its color to blend in with its surroundings. The change of color is a defense mechanism against predators such as raccoons, bullfrogs, snakes, heron, and many others. Pacific Tree Frogs also change their color based on the seasons and temperature. When the temperatures are high, they turn into a shade of yellow. An example of Pacific Tree Frog species that changes color is Hyla regilla. The process of color change in Pacific Tree Frogs takes 1-2 minutes.

6. Seahorses

Seahorses, such as the thorny seahorse, are among the marine animals that have mastered changing their color. The purpose of changing their skin color is to camouflage, frighten predators, communicate their emotions, and for courtship. Complex interactions between the brain, nervous system, hormones, and organelles make it possible for the seahorses to change their color. The organelles responsible for these color changes are known as chromatophores. Regarding the speed at which the skin color changes, this depends on the stimulus. For instance, in a life or death situation such as involving a predator, the color changes quickly. But whenever the seahorse is courting a mate, the change takes place slowly.

5. Flounders

Flounders are naturally brown. However, they can change color to suit their surroundings. A flounder uses its vision and specialized cells inside the skin to change color. The cells, in turn, have color pigments and are linked to the eyes of the flounders. When a flounder moves to a new environment, the retina in the eyes captures the new color. Consequently, the color seen by the eyes are transmitted to the cells. The cells adjust the pigmentation to match the surface color. Scientists have discovered that flounders depend entirely on their vision to change color. When their eyes are damaged, then they have difficulties in camouflaging to their surrounding. An example of flounder species that changes color is the peacock flounder.

4. Cuttlefish

Cuttlefish are cephalopods that change color to feed on prey and avoid predators craftily. They have three mechanisms by which they can change color. Firstly, the cuttlefish skin contains papillae that alter the tone of the fish. The papillae cause the skin to become smooth or rough depending on the environment. Secondly, camouflaging is possible because of the chromatophores in their skin. The chromatophores are sacs of color pigments. To change color, these sacs receive color-changing instructions from the brain and act accordingly. Lastly, cuttlefish have reflecting plates called leucophores and iridophores. The plates enable the fish to change its color.

3. Crab Spiders

Spiders called flower spiders (or crab spiders) change their color. They usually change color to hide from their prey. Consequently, the spiders change color to resemble the flower surface on which they sit through the reflection of light. Some spiders release a yellow pigment that enhances their color changing process. An example of a species of spider with such color changing features is Misumenoides formosipes and Misumena vatia. The color change from white to yellow takes 10-25 days. Hence, the flower spiders patiently wait for the completion of the process before they can attack their prey.

2. Squid

Squids are marine cephalopods. They possess two long tentacles and eight arms. An interesting fact about the squids is that their blood is blue. Furthermore, they have three hearts instead of one like other fish. The squids are uniquely beautiful and able to change color. They change color using chromatophores engraved in their skin. The purpose of changing color is to match the surface they are on so that they can avoid predators. The camouflage also acts as a hunting tactic since it enables them to hide away from their prey.

1. Cyanea Octopus

Known as the big blue octopus or the day octopus, octopus cyabea is found in the waters of the Indo-Pacific. It is known as the day octopus as it is most active during the daytime in contrast to most other octopus species. The cyanea octopus is especially adept at camouflage, able to not only frequently change the color of their skin, but also recreate patterns and textures. On the hunt for crabs, molluscs, shrimp, and fish, the cyanea octopus is able to quickly adapt its appearance to its surroundings, even mimicking moving shadows such as overhead clouds.

Color Change in Plants And Flowers

Color change in Leaves and Flowers

  • Chlorophyll – Green
  • Cartenoids – Xanthophylls – Yellow as in Corn
  • Cartenoids – Carotenes – Orange as in Carrots
  • Anthrocyanins – Blueberries and Cherries – Blue, purple, red, pink
  • Flavonols – Pale yellows and whites

Plants change colors

  • Change in Heat
  • Change in pH
  • During the Fall
  • During the day

Color Fading and Color Metamerism are also important problems but are not discussed in this post.

Source: The science behind why leaves change color in autumn

A rainbow of autumn colors

The green color of chlorophyll is so strong that it masks any other pigment. The absence of green in the fall lets the other colors come through. Leaves also contain the pigments called carotenoids; xanthophylls are yellow (such as in corn) and carotenes are orange (like in carrots). Anthocyanins (also found in blueberries, cherries) are pigments that are only produced in the fall when it is bright and cold. Because the trees cut off most contact with their leaves at this point, the trapped sugar in the leaves’ veins promotes the formation of anthocyanins, which are used for plant defense and create reddish colors.

However, trees in the fall aren’t just yellow and red: they are brown, golden bronze, golden yellow, purple-red, light tan, crimson, and orange-red. Different trees have different proportions of these pigments; the amount of chlorophyll left and the proportions of other pigments determine a leaf’s color. A combination of anthocyanin and chlorophyll makes a brown color, while anthocyanins plus carotenoids create orange leaves.

Source: The science behind why leaves change color in autumn

Source:https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/hibiscus-turning-different-color.htm

Can Hibiscus Change Color: Reasons For Hibiscus Turning A Different Color

07/20/20

Can hibiscus change color? The Confederate Rose (Hibiscus mutabilis) is famous for its dramatic color changes, with flowers that can go from white to pink to deep red within one day. But almost all hibiscus varieties produce flowers that can change colors under certain circumstances. Read on to learn more.

Reasons for Color Changing in Hibiscus

If you’ve ever noticed the flowers on your hibiscus turning a different color, you’ve probably wondered what was behind the change. To understand why this happens, we need to look at what creates flower colors in the first place.

Three groups of pigments create the vibrant color displays of hibiscus flowers. Anthocyanins produce blue, purple, red, and pink colors, depending on the individual pigment molecule and the pH it is exposed to. Flavonols are responsible for pale yellow or white colors. Carotenoids create colors on the “warm” side of the spectrum – yellows, oranges, and reds.

Each hibiscus variety has its own genetics that determine what pigments, and what range of colors it can produce. However, within that range, temperature, sunlight, pH, and nutrition can all affect the levels of different pigments in a flower and what color they appear.

The blue- and red-colored anthocyanins are water-soluble pigments carried in plant sap. Meanwhile, the red, orange and yellow carotenoids are fat-soluble pigments created and stored in the plastids (compartments in plant cells similar to the chloroplasts that carry out photosynthesis). Therefore, anthocyanins are less protected and more sensitive to environmental changes, while carotenoids are more stable. This difference helps explain the color changes in hibiscus.

Anthocyanins exposed to hot conditions will often break down, causing flower colors to fade, while carotenoid-based colors hold up well in the heat. High temperatures and bright sunlight also enhance carotenoid production, leading to bright reds and oranges.

On the other hand, plants produce more anthocyanins in cold weather, and the anthocyanins they produce tend to be more red- and pink-colored as opposed to blue or purple. For this reason, some anthocyanin dependent hibiscus flowers will produce brilliant color displays during cool weather or in partial shade, but will fade in bright, hot sunlight.

Similarly, flavonols exposed to high temperatures will fade from yellow to white, while cold weather will cause an increase in production and a deepening of yellow flower colors.

Other Factors in Hibiscus Color Change

Some anthocyanin pigments will change color depending on the pH they’re exposed to within the flower. The pH doesn’t usually change over time within a hibiscus flower because it is determined genetically, but patches of different pH levels can lead to multiple colors occurring within one flower.

Nutrition is also a factor in color changes. Adequate sugar and protein in the sap are required for anthocyanin production. Making sure your plant has enough fertility and nutrients is important for vibrant colors in anthocyanin dependent flowers.

So, depending on its variety, your hibiscus changed color because of some combination of temperature, sunlight, nutrition, or pH has taken place. Can gardeners control this hibiscus color change? Yes, indirectly – by controlling the plant’s environment: shade or sun, good fertility, and protection from hot or cold weather.

Source: https://www.loc.gov/everyday-mysteries/botany/item/what-causes-flowers-to-have-different-colors/

What causes flowers to have different colors?

Answer

Anthocyanins and carotenoids… plus some other things.

Flowers come in all shapes and sizes, but what makes them truly stand apart from each other is their vibrant colors.  These colors are made up of pigments and, generally speaking, the fewer the pigments, the lighter the color.  The most common pigments in flowers come in the form of anthocyanins.  These pigments range in color from white to red to blue to yellow to purple and even black and brown.  A different kind of pigment class is made up of the carotenoids.  Carotenoids are responsible for some yellows, oranges, and reds.  (These little guys are what cause the brilliant colors of autumn leaves!)  While many flowers get their colors from either anthocyanins or carotenoids, there are some that can get their colors from a combination of both.

Anthocyanins and carotenoids are the main sources of flower coloration, but there are other factors that can affect how colors present themselves.  The amount of light flowers receive while they grow, the temperature of the environment around them, even the pH level of the soil in which they grow can affect their coloration.  Another factor is stress from the environment.  This stress can include a drought or a flood or even a lack of nutrition in the soil, all of which can dampen the coloration of flowers.  And then, of course, there is the visual that the eye and brain form together: humans can, for the most part, view all colors in the visible spectrum, BUT every human perceives color differently, so a red rose may appear more vibrant to one person while it appears more muted to another.  Beauty (and color!) is in the eye of the beholder.

My Related Posts

Digital Color and Imaging

Color and Imaging in Digital Video and Cinema

On Light, Vision, Appearance, Color and Imaging

On Luminescence: Fluorescence, Phosphorescence, and Bioluminescence

Key Sources of ResearCH

Photochromic and Thermochromic Colorants in Textile Applications

M. A. Chowdhury, M. Joshi and B. S. Butola

https://journals.sagepub.com/doi/pdf/10.1177/155892501400900113

THE CHEMISTRY & PHYSICS OF
SPECIAL EFFECT PIGMENTS & COLORANTS

A. NURHAN BECIDYAN

President
UNITED MINERAL & CHEMICAL CORPORATION

PHOTOLUMINESCENTS: FLUORESCENT AND PHOSPHORESCENT INKS AND PAINTS

Structural colour and iridescence in plants: the poorly studied relations of pigment colour

Beverley J. Glover1,* and  Heather M. Whitney2

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2850791/

Analysing photonic structures in plants 

Silvia Vignolini1,2, Edwige Moyroud3, Beverley J. Glover3 and Ullrich Steiner1

1Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK 2Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK 3Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK

The Mechanism of Color Change in the Neon Tetra Fish: a Light‐Induced Tunable Photonic Crystal Array

Dvir Gur 1 , Benjamin A Palmer 1 , Ben Leshem 2 , Dan Oron 2 , Peter Fratzl 3 , Steve Weiner 1 , Lia Addadi 4

First published: 27 April 2015

https://pubmed.ncbi.nlm.nih.gov/25914222/

10 Animals that can Change Colors

https://www.worldatlas.com/articles/10-animals-that-can-change-colors.html

How Octopuses and Squids Change Color

https://ocean.si.edu/ocean-life/invertebrates/how-octopuses-and-squids-change-color

Why color-changing animals alter their appearance

By Zach Fitzner

Earth.com staff writer

Iridophores and their interactions with other chromatophores are required for stripe formation in zebrafish

Hans Georg Frohnhöfer, Jana Krauss, Hans-Martin Maischein, Christiane Nüsslein-Volhard

Development  2013  140: 2997-3007;  doi: 10.1242/dev.096719

https://dev.biologists.org/content/140/14/2997.article-info

Magic Traits in Magic Fish: Understanding Color Pattern Evolution Using Reef Fish

Author links open overlay panelPaulineSalis1ThibaultLorin2VincentLaudet1BrunoFrédérich3

https://www.sciencedirect.com/science/article/abs/pii/S0168952519300162

Developmental and comparative transcriptomic identification of iridophore contribution to white barring in clownfish. 

https://www.x-mol.com/paper/959131

Rapid integumental color changes due to novel iridophores in the chameleon sand tilefish Hoplolatilus chlupatyi

Makoto Goda

First published: 13 February 2017 https://doi.org/10.1111/pcmr.12581

https://onlinelibrary.wiley.com/doi/abs/10.1111/pcmr.12581

Flashing Tilefish’s Color Changing Skin is Unique in the Animal World

Top 10 Colour Changing Animals Around the World

Chameleon-Inspired Variable Coloration Enabled by a Highly Flexible Photonic Cellulose Film

  • Ze-Lian Zhang, 
  • Xiu Dong, 
  • Yi-Ning Fan, 
  • Lu-Ming Yang, 
  • Lu He, 
  • Fei Song*
  • Xiu-Li Wang, and 
  • Yu-Zhong Wang*

Cite this: ACS Appl. Mater. Interfaces 2020, 12, 41, 46710–46718Publication Date:September 23, 2020

https://pubs.acs.org/doi/10.1021/acsami.0c13551

The secret to chameleon color change: Tiny crystals

By Robert F. ServiceMar. 10, 2015 

https://www.sciencemag.org/news/2015/03/secret-chameleon-color-change-tiny-crystals

Amazing Octopus Color Transformation | National Geographic

How do Octopuses Change Color?

Here’s everything you ever wanted to know about chromatophores.

Study demonstrates that octopus’s skin possesses same cellular mechanism for detecting light as its eyes do

by  University of California – Santa Barbara

https://phys.org/news/2015-05-octopus-skin-cellular-mechanism-eyes.html

Progress and Opportunities in Soft Photonics and Biologically Inspired Optics

Mathias KolleSeungwoo Lee

First published: 23 October 2017

https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.201702669

https://pubmed.ncbi.nlm.nih.gov/29057519/

https://onlinelibrary.wiley.com/doi/am-pdf/10.1002/adma.201702669

Bioinspired living structural color hydrogels

Fanfan Fu, Luoran Shang, Zhuoyue Chen, Yunru Yu, Yuanjin Zhao

Smart pigments with reactive nanocolors printed on paper and flexibles

2009 International Conference on Nanotechnology for the Forest Products Industry

Click to access 09nan23.pdf

Thermochromic Material

https://www.sciencedirect.com/topics/engineering/thermochromic-material

Color Changing Plastics for Food Packaging

By

Lizanel Feliciano
Ohio State University, Columbus, Ohio

Smart dyes for medical and other textiles

  • February 2007

DOI: 10.1533/9781845692933.1.123

Tatjana Rijavec, Sabina Bračko

University of Ljubljana

https://www.researchgate.net/publication/288402591_Smart_dyes_for_medical_and_other_textiles

Thermochromic colors in textiles

S. Periyasamy, Gaurav Khanna

https://www.fibre2fashion.com/industry-article/3059/thermochromic-colors-in-textiles

“Smart” fluorescent dyes change color in different solid states

Aug 21st, 2018

https://www.laserfocusworld.com/lasers-sources/article/16571232/smart-fluorescent-dyes-change-color-in-different-solid-states

Materials that Change Color

Smart Materials, Intelligent Design
  • Marinella Ferrara
  • Murat Bengisu

https://link.springer.com/book/10.1007%2F978-3-319-00290-3#about

Switching Colors with Electricity

BY  ROGER J. MORTIMER

American Scientist

JANUARY-FEBRUARY 2013

VOLUME 101, NUMBER 1

https://www.americanscientist.org/article/switching-colors-with-electricity

Smart textiles change colour on demand


Friday, 13 May 2016

https://portal.engineersaustralia.org.au/news/smart-textiles-change-colour-demand

Design Concepts for a Temperature-sensitive Environment Using Thermochromic Colour Change

Robert M Christie, Sara Robertson and Sarah Taylor

Colour: Design & Creativity (2007) 1 (1): 5, 1–11

Smart responsive phosphorescent materials for data recording and security protection

Huibin Sun1,2,􏰀, Shujuan Liu1,􏰀, Wenpeng Lin1, Kenneth Yin Zhang1, Wen Lv1, Xiao Huang2, Fengwei Huo2, Huiran Yang1, Gareth Jenkins1,2, Qiang Zhao1 & Wei Huang1,2

Received 21 Oct 2013 | Accepted 10 Mar 2014 | Published 7 April 2014

NATURE COMMUNICATIONS 

https://www.nature.com/articles/ncomms4601.pdf?origin=ppub

Anthocyanin food colorant and its application in pH-responsive color change indicator films

Swarup Roy & Jong-Whan Rhim (2020)

Critical Reviews in Food Science and Nutrition,

DOI: 10.1080/10408398.2020.1776211

Smart monitoring of gas/temperature changes within food packaging based on natural colorants

COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY

2020;19:2885–2931.

DOI: 10.1111/1541-4337.12635

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1111/1541-4337.12635

Smart textiles: an overview of recent progress on chromic textiles

Heloisa Ramlow Karina Luzia Andrade  & Ana Paula Serafini Immich 

Pages 152-171 | Received 20 Feb 2019, Accepted 24 Oct 2019, Published online: 29 Jun 2020

The Journal of The Textile Institute Volume 112, 2021 – Issue 1

https://www.tandfonline.com/doi/abs/10.1080/00405000.2020.1785071

Anthocyanin – A Natural Dye for Smart Food Packaging Systems

Suman Singh1, Kirtiraj K. Gaikwad2, and Youn Suk Lee3*

https://www.semanticscholar.org/paper/Anthocyanin-–-A-Natural-Dye-for-Smart-Food-Systems-Singh-Forestry/4f41ec48d77d61bc05decd7738a672f414f9b2db?p2df

Critical Review on Smart Chromic Clothing

Esraa El-Khodary1, Bahira Gebaly2, Eman Rafaat2, Ahmed AlSalmawy2

Colorimetric properties of reversible thermochromic printing inks

Rahela Kulcar a, Mojca Friskovec b, Nina Hauptman c, Alenka Vesel d, Marta Klanjsek Gunde

Dyes and Pigments 86 (2010) 271e277

Designing Smart Textiles Prints with Interactive Capability

Prof. Hoda Abdel Rahman Mohamed El-Hadi 1 ,Prof. Sherif Hassan Abdel Salam 2 Eng. Kholoud Hassan Mohamed Mahmoud

Smart Chromic Colorants Draw Wide Attention for the Growth of Future Intelligent Textile Materials

Amit Sengupta#& Jagadananda Behera

Wool Research Association, Thane, India

LEUCO DYE-BASED THERMOCHROMIC INKS: RECIPES AS A GUIDE FOR DESIGNING TEXTILE SURFACES

MARJAN KOOROSHNIA Swedish School of Textiles

Relation between colour- and phase changes of a leuco dye-based thermochromic composite

Scientific Reports volume 8, Article number: 5511 (2018)

https://www.nature.com/articles/s41598-018-23789-2

The Chemistry and Physics of Special-Effect Pigments and Colorants for Inks and Coatings

Paints and Coatings

2003

https://www.pcimag.com/articles/85016-the-chemistry-and-physics-of-special-effect-pigments-and-colorants-for-inks-and-coatings

THERMOCHROMIC MATERIAL MARKET

https://www.mordorintelligence.com/industry-reports/thermochromic-material-market

QCR Solutions Corp

OliKrom

The Effective Use of Interference and Polychromatic Colorants

https://www.pcimag.com/articles/102445-the-effective-use-of-interference-and-polychromatic-colorants

White reflection from cuttlefish skin leucophores

Cephalopod Camouflage: Cells and Organs of the Skin

https://www.nature.com/scitable/topicpage/cephalopod-camouflage-cells-and-organs-of-the-144048968/

Chromatophore Organs, Reflector Cells, Iridocytes and Leucophores in Cephalopods

RICHARD A. CLONEY AND STEVEN L. BROCCO

Mechanisms and behavioural functions of structural coloration in cephalopods

Lydia M. Ma ̈thger1,2,3,*,†, Eric J. Denton3,‡, N. Justin Marshall2 and Roger T. Hanlon1

J. R. Soc. Interface (2009) 6, S149–S163

Cephalopod Camouflage: Cells and Organs of the Skin

https://www.nature.com/scitable/topicpage/cephalopod-camouflage-cells-and-organs-of-the-144048968/

Chromatophore

https://en.wikipedia.org/wiki/Chromatophore

Leucophores are similar to xanthophores in their specification and differentiation processes in medaka

https://www.researchgate.net/publication/262111984_Leucophores_are_similar_to_xanthophores_in_their_specification_and_differentiation_processes_in_medaka

Identification and Characterization of Highly Fluorescent Pigment Cells in Embryos of the Arabian Killifish (Aphanius Dispar)

On leucophores and the chromatic unit of Octopus vulgaris

D. Froesch1J. B. Messenger2

https://zslpublications.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-7998.1978.tb03363.x

Adaptive camouflage helps blend into the environment 

Cuttlefish

https://asknature.org/strategy/adaptive-camouflage-helps-blend-into-the-environment/

Identification of kit-ligand a as the Gene Responsible for the Medaka Pigment Cell Mutant few melanophore

THE SECRET OF A SQUID’S ABILITY TO CHANGE COLORS MAY LIE IN AN UNEXPECTED SPARKLE ON ITS SKIN

INVISIBILITY IS (ALMOST) POSSIBLE WHEN HUMAN CELLS ARE MERGED WITH SQUID GENES

https://www.syfy.com/syfywire/human-cells-merged-with-squid-invisibility-trait

How Cephalopods Change Color

By Dr. James Wood and Kelsie Jackson

ELECTRONIC PAPER DISPLAYS: Kindles and cuttlefish: Biomimetics informs e-paper displays

https://www.laserfocusworld.com/detectors-imaging/article/16549524/electronic-paper-displays-kindles-and-cuttlefish-biomimetics-informs-epaper-displays

Skin paterning in Octopus vulgaris and its importance for camouflage

Iridophores and Not Carotenoids Account for Chromatic Variation of Carotenoid-Based Coloration in Common Lizards ( Lacerta vivipara ).

Biological vs. Electronic Adaptive Coloration: How Can One Inform the Other?

Eric Kreit1, Lydia M. Mäthger2, Roger T. Hanlon2, Patrick B. Dennis3, Rajesh R. Naik3, Eric Forsythe4 and Jason Heikenfeld1*

The Chemistry of Biological Camouflage

https://www.chemistryislife.com/the-chemistry-of-biological-camouflage

Mechanisms and behavioural functions of structural coloration in cephalopods

https://espace.library.uq.edu.au/view/UQ:170626

Sepiida algorithm for solving optimal reactive power problem

Are You Ready for Plants That Change Color?

Why Leaves Change Color

https://www.esf.edu/pubprog/brochure/leaves/leaves.htm

Can Hibiscus Change Color: Reasons For Hibiscus Turning A Different Color

https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/hibiscus-turning-different-color.htm

What causes flowers to have different colors?

https://www.loc.gov/everyday-mysteries/botany/item/what-causes-flowers-to-have-different-colors/

The science behind why leaves change color in autumn

Why has my plant’s flower changed colour?

Why Does Cannabis Change Colors?

https://cannabis.net/blog/strains/why-does-cannabis-change-colors

A cyborg plant with color-changing leaves? Scientists just rose to the challenge.

https://www.washingtonpost.com/news/speaking-of-science/wp/2015/11/23/a-cyborg-plant-with-color-changing-leaves-scientists-just-rose-to-the-occasion/

Color-changing plants detect pollutants and explosives

https://newatlas.com/color-changing-plants-detect-pollutants-and-explosives/17915/

The Color Genes of Speciation in Plants

Daniel Ortiz-Barrientos1

Genetics. 2013 May; 194(1): 39–42.
doi: 10.1534/genetics.113.150466

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3632479/

Guide to Fall Colors in Upstate New York

Donald J. Leopold
Chair, Department of Environmental and Forest Biology and Distinguished Teaching Professor
SUNY-ESF, Syracuse

The plants that change colour through the seasons

https://www.stuff.co.nz/life-style/home-property/nz-gardener/76979012/the-plants-that-change-colour-through-the-seasons

Colours of plants and animals

https://www.itp.uni-hannover.de/fileadmin/arbeitsgruppen/zawischa/static_html/botzooE.html

On Luminescence: Fluorescence, Phosphorescence, and Bioluminescence

Key Words

  • Photoluminescence
  • Fluorescence
  • Phosphorescence
  • Chemiluminescence
  • Luminescence
  • Incandescence
  • Spectrophotometer
  • Spectrofluorophotometer
  • Bioluminescence
  • Chemluminescence
  • Mechnoluminescence
  • Thermoluminescnce
  • Sonoluminescence
  • Electroluminescence
  • Daylight Fluorescent dyes
  • UV Fluorescent Dyes
  • Angle dependent Pigments in coatings
  • Optical Effects
  • Opalescence
  • Iridescence
  • Pearlescence
  • Adularescence
  • Labradorescence
  • Aventurescence
  • GonioSpectrometers
  • Multi Angle Spectrophotometers

There are many forms of energy which selected luminescent pigments can absorb and convert to luminescence, e.g. radioactive (radioluminescence); X-ray (Roentgenoluminescence); cathode ray (cathodoluminescence); mechanical (triboluminescence); electrical (electroluminescence); heat -after previous storage of energy (thermoluminescence); and Ultraviolet (UV) visible and Infrared (IR) (photoluminescence).

Luminescence Vs Incandescence

  • Incandescence
  • Luminescence
    • Bioluminescence
    • Photoluminescence
      • Fluorescence
      • Phosphorescence

Source:

Source:

Source: Introduction/Molecular Fluorescence: Principles and Application

Source: FLUORESCENCE AND PHOSPHORESCENCE

Source: Introduction/Molecular Fluorescence: Principles and Application

Bioluminescence

Please see references listed below for examples of bioluminescence.

  • In plants
    • Reviewing the relevance of fluorescence in biological systems
    • PLANTS WITH SELF-SUSTAINED LUMINESCENCE
  • In ocean Life
    • BIOLUMINESCENCE IN THE SEA
  • Fireflies
    • RESURRECTING THE ANCIENT GLOW OF THE FIREFLIES

Photoluminescence

  • Fluorescence
  • Phasphorescence

Source: Fluorescence and Phosphorescence

Jablonski Diagram – Molecular States

Source: Fluorescence and Phosphorescence

Source: Fluorescence and Phosphorescence

Fluorescence

Types of Fluorescence

  • Daylight
  • UV

Fluorescent Dyes and Pigments

Source: Fluorescent Dyes and Pigments

1.Introduction
2.Naphthalimide Dyes
3.Coumarin Dyes
4.Xanthene Dyes
5.Thioxanthene and Benzoxanthene Dyes
6.Naphtholactam, Hydrazam Dyes and Homologues
7.Azlactone Dyes
8.Methine Dyes
9.Oxazine and Thiazine Dyes
10.Miscellaneous Fluorescent Dyes
11.UV Fluorescent Chromophores with No or Low Body Color
12.Special Uses
13.Daylight Fluorescent Pigments
13.1.Production
13.1.1.Dyes for Daylight Fluorescent Pigments
13.1.2.Pigment Matrices
13.1.3.Formaldehyde‐Free and Solvent Resistant Fluorescent Pigments
13.1.4.Sunlight Sensors
13.1.5.Fluorescent Modifications with Covalently Bound Dyes
13.1.6.More ‐ Not Resinated ‐ Solid‐State Fluorescent Pigments
13.2.Quality Specifications of Fluorescent Pigments
13.3.Applications of Fluorescent Pigments
13.4.Toxicology

Industrial Applications of Fluorescence

  • Paper
  • Plastics
  • Paints
  • Textiles
  • Printing Inks
  • Laudary Detergent

In Paper Industry

  • Disulfonated OBA – used in wetend of paper machines
  • Tetrasulfonated OBA – surface coating in size press for standard whiteness
  • Hexasulfonated OBA- for high whiteness

Optical brightening agents in paper

Posted on April 6, 2018 by admin

Optical brightening agents are additives which are used in the paper industries to enhance whitening effects of papers. These chemical compounds absorb light in the ultraviolet and violet region (usually 340-370nm) and re-emit light in the blue region (typically 420-470 nm). It gives a fluorescent effect that masks the inherent yellowness of the fiber and enhances the brightness of the paper product. They not only used in paper but also used in plastics, textiles, laundry detergents. They are also known as optical brighteners, artificial whiteners. It is one kind of coating agent.

The optical brighteners can be applied in either the wet end or dry end or both end. If you want to internal brightness then you have to add them to the stock in wet end. Many paper manufactures use them in dry end at the size press or calender stack as surface coating. The dry end application is more economical compare to the wet end because in the dry end the chemical are used on the outer surface fiber in lieu of whole fiber content for reflects the ultraviolet light. However some manufacturers use a combination treatment; they use both the wet and dry end. 

Types of optical brightening agents

The optical brighteners that are used in paper industries can be sort into three types based on the sulfonic groups. All of them contain stilbene structure.

Disulfonated OBAs

This OBAs contains two sulphonic groups. They are hydrophobic and have a very good affinity. The solubility is very low. Normally it is used in wet end.

Tetrasulfonated types

This OBAs contains four sulphonic groups. It has medium affinity and good solubility so ideal for paper industries both in wet end and dry end. They are suitable for neutral or alkaline pH medium. It is most common type of OBAs that are used in paper and paper board.

Hexasulfonated OBAs

hexasulfonated OBAs contains six sulphonic groups. It is special type of brightener which has excellent solubility. Mostly it is used in those papers where high brightness is required such as photographic paper. They are used in dry end as coating.

Optical brightener’s chemistry

We know that optical brightening agents are stilbene derivatives. The stilbene is a diphenylethene which consist two stereo-isomer – trans-isomer and cis-isomer. Between these two configurations, the trans-isomer can exhibits strong fluorescence whereas the cis-isomer does not exhibit fluorescence. The trans configuration is more stable than cis configuration but when the uv light applied on the trans configuration then it become electronically exited and converted into cis configuration. Consequently the fluorescence phenomenon occurs in. The visible blue light effectively neutralizes the cream color or yellowish hue of the paper fiber.

Disadvantage

All the optical brightening agents are dyestuffs. As like most of the other colorants they also degraded by oxygen in air slowly. So after several years or months, the increasing brightness of the paper with optical brighteners will decrease. As a result the printed paper will not look good. Thus some people does not like print on the paper with artificial brightness. Similarly it is not useful in photographic or art applications. On the other hand in some places or some printers the OBAs would not work. Therefore the paper will appear its normal brightness. This is the reason why some printed papers have a yellowish hue. Although the OBAs are efficient on bleached chemical pulps but it is ineffective on unbleached pulp due to lignin is also an ultraviolet absorbing agent.

Finally

Normally the consumers expect higher brightness paper and paper boards. But all the time the brightness of pulp and fillers cannot fulfill the targeted brightness. Therefore the manufactures use different type of optical brightening agents. Most of the paper manufacturers add these chemicals in order to make paper appear brighter.

Source: The issues of Optical Brightening Agents in paper and ink

Industrial Testing and Measurements

Source: Fluorescence and Phosphorescence

Source: Fluorescence and Phosphorescence

Source: Fluorescence and Phosphorescence

Source: Fluorescence and Phosphorescence

Fluorescence Prediction and Control

Please see my post related to Color and Fluorescence Meaurement, Prediction and Control.

On Light, Vision, Appearance, Color and Imaging

There are also several references in the list below which describe fluorescence measurement, prediction, and control in more detail. Papers by LG Coppel describe fluorescence modelling. Papers by Tarja Shakespeare describe fluorescence modeling and control online on paper machines.

My Related Posts

Digital Color and Imaging

Color and Imaging in Digital Video and Cinema

On Light, Vision, Appearance, Color and Imaging

Key Sources of Research

Constructing Models to Explain Photoluminescence

Fluorescence, Phosphorescence, and Chemiluminescence

Noureen Siraj,† Bilal El-Zahab,‡ Suzana Hamdan,† Tony E. Karam,† Louis H. Haber,† Min Li,§
Sayo O. Fakayode,∥ Susmita Das,⊥ Bertha Valle,⊗ Robert M. Strongin,○ Gabor Patonay,#
Herman O. Sintim,× Gary A. Baker,$ Aleeta Powe,¶ Mark Lowry,○ Jan O. Karolin,& Chris D. Geddes,& and Isiah M. Warner*,†

Anal. Chem. 2016, 88, 170−202

Reviewing the relevance of fluorescence in biological systems

https://pubs.rsc.org/en/content/getauthorversionpdf/c5pp00122f

Pigments, dyes and fluorescent brightening agents for plastics: An overview

Robert M. Christie

First published: August 1994

https://onlinelibrary.wiley.com/doi/abs/10.1002/pi.1994.210340401

FLUORESCENT DYES FOR PAPER DYEING

Inventor: Helmut-MartinMeier,Ratingen(DE)

Assignee: KemiraGermanyGmbH,Leverkusen (DE)

Photochromic and Thermochromic Colorants in Textile Applications

M. A. Chowdhury, M. Joshi and B. S. Butola

https://journals.sagepub.com/doi/pdf/10.1177/155892501400900113

THE CHEMISTRY & PHYSICS OF
SPECIAL EFFECT PIGMENTS & COLORANTS

A. NURHAN BECIDYAN

President
UNITED MINERAL & CHEMICAL CORPORATION

Luminescence Phenomena: An Introduction

K.V.R. Murthy

Hardev Singh Virk

https://www.researchgate.net/publication/271866484_Luminescence_Phenomena_An_Introduction

Introduction

Molecular Fluorescence: Principles and Applications, Second Edition. Bernard Valeur,
Mário Nuno Berberan-Santos.
© 2013 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2013 by Wiley-VCH Verlag GmbH & Co. KGaA.

A Brief History of Fluorescence and Phosphorescence before the Emergence of Quantum Theory

Bernard Valeur*,† and Mario N. Berberan-Santos*,‡

Plants with self-sustained luminescence

Tatiana Mitiouchkina et all

Bioluminescence in the Sea

Steven H.D. Haddock,1 Mark A. Moline,2 and James F. Case3

Resurrecting the ancient glow of the fireflies

PHOTOLUMINESCENTS: FLUORESCENT AND PHOSPHORESCENT INKS AND PAINTS

An Introduction to Fluorescence Spectroscopy

Fluorescence Spectroscopy

Molecular Fluorescence, Phosphorescence, and Chemiluminescence Spectrometry

https://pubs.acs.org/doi/pdf/10.1021/ac00084a016

Molecular Luminescence Spectrometry

Molecular Fluorescence, Phosphorescence, and Chemiluminescence Spectrometry

Anal Chem. 2006 Jun 15; 78(12): 4047–4068.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2662353/

Fluorescence and phosphorescence

Fluorescence and Phosphorescence

Practical Capture and Reproduction of Phosphorescent Appearance

O. Nalbach1, H.-P. Seidel1 and T. Ritschel2

1Max-Planck Institut für Informatik, Germany 2University College London, United Kingdom

Fluorescent Dyes and Pigments

Rami Ismael Hansrudolf Schwander Paul Hendrix

Dyes, optical brightening agents

Permanency of paper and board

Structural colour and iridescence in plants: the poorly studied relations of pigment colour

Beverley J. Glover1,* and  Heather M. Whitney2

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2850791/

Analysing photonic structures in plants 

Silvia Vignolini1,2, Edwige Moyroud3, Beverley J. Glover3 and Ullrich Steiner1

1Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK 2Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK 3Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK

The Mechanism of Color Change in the Neon Tetra Fish: a Light‐Induced Tunable Photonic Crystal Array

Dvir Gur 1 , Benjamin A Palmer 1 , Ben Leshem 2 , Dan Oron 2 , Peter Fratzl 3 , Steve Weiner 1 , Lia Addadi 4

First published: 27 April 2015

https://pubmed.ncbi.nlm.nih.gov/25914222/

Colour measurement in the paper industry

https://www.erx50.com/en/anwendungen/papier-obsolete

Print Quality Control Management for Papers Containing Optical Brightening Agents

Roberto Pasic, Ivo Kuzmanov, Svetlana Mijakovska

The issues of Optical Brightening Agents in paper and ink

http://the-print-guide.blogspot.com/2009/03/issues-of-optical-brightening-agents-in.html

Optical Brightening Agents in Manufacturing

Posted July 20, 2015 by Greg Stehn

https://www.xrite.com/blog/controlling-obas-in-manufacturing

SUCCESSFUL COLOR MANAGEMENT OF PAPERS WITH OPTICAL BRIGHTENERS

Effect of Optical Brightening Agents and UV Protective Coating on Print Stability of Fine Art Substrates for Ink Jet

Veronika Chovancova-Lovell* and Paul D. Fleming III**

*Daniel J Carlick Technical Center Sun Chemical Corporation

**Department of Paper Engineering, Chemical Engineering and Imaging, Center for Ink and Printability Western Michigan University

OPTICAL BRIGHTENING AGENTS

A Visual Examination of the Solubility of Brighteners in Paper after Aqueous Treatment

Emily H. Cohen

December 17, 2014

Color & Perception Roemich

To Brighten or Not to Brighten

Scientifically examining the controversy over OBA inkjet media additives.

SIGN & DIGITAL GRAPHICS • July 2009

Substitution of Optical Brightener Agents in Industrial Textiles

MUDP report October 2018

Denmark

Chemistry of optical brighteners and uses in textile industries

by Mr. Anwer Tiki, Afreen Amin and Azeema Kanwal, AVM Chemical Industries.

Archroma Introduces Leucophor® MT, A New Cost-Effective Optical Brightening Agent For High Whiteness Surface Applications

Reinach, Switzerland – 20/02/2018

https://www.archroma.com/press/releases/archroma-introduces-leucophor-mt-a-new-cost-effective-optical-brightening-agent-for-high-whiteness-surface-applications

Whiteness indices and UV standards

Konica Minolta

https://www5.konicaminolta.eu/ru/measuring-instruments/learning-centre/colour-measurement/colour/the-colour-of-white.html

The Effect of Optical Brightening Agent (OBA) in Paper and Illumination Intensity on Perceptibility of Printed Colors

Changlong Yu 2014

RIT MS Thesis

Demystifying Three Key Paper Properties

Whiteness, Brightness and Shade

Xerox

The Evolution of Tinting Dyes and Optical Brighteners in White Papers

Mark Crable

Greenville Colorants

Addressing the Challenges of Optical Brightening Agents in Paper Color Measurement

Posted on  December 4, 2015 by Ken Phillips

Hunter Lab

Adding optical brightening agents to high-yield pulp at the pulp mill

Review: Use of optical brightening agents (OBAs) in the production of paper containing high-yield pulps

Shi, H., Liu, H., Ni, Y., Yuan, Z., Zou, X., and Zhou, Y. (2012). 

BioRes. 7(2), 2582-2591.

FLUORESCENT WHITENING AGENTS IN LAUNDRY DETERGENT & PAPER

https://www.sas.upenn.edu/~kimg/mcephome/chem507/spec6.html

A summary of ultra-violet fluorescent materials relevant to Conservation


AICCM National Newsletter No 137 March 2017

Danielle Measday, Museums Victoria

Efficiency of Fluorescent Whitening Agents in Pigment Coatings

Zaeem Aman 2012

Master Thesis
Master of Science in Chemical Engineering

Karlstads universitet (KAU) 651 88 Karlstad

Colour Chemistry 2nd edition

Robert M Christie

School of Textiles & Design, Heriot-Watt University, UK and Department of Chemistry, King Abdulaziz University, Saudi Arabia

Email: r.m.christie@hw.ac.uk

Colour and the Optical Properties of Materials

An Exploration of the Relationship Between Light, the Optical Properties of Materials and Colour

PROFESSOR RICHARD J. D. TILLEY

Emeritus Professor, University of Cardiff, UK

2011 John Wiley & Sons, Ltd

FLUORESCENCE AND PHOSPHORESCENCE

Andrew Glassner

Rendering of fluorescent materials using spectral path tracing : Niixtracer, a custom rendering engine

Nolan MESTRES

2018

Spectral Mollification for Bidirectional Fluorescence

A. Jung1, J. Hanika1 and C. Dachsbacher1 1Karlsruhe Institute of Technology

Assessment of whiteness and tint of fluorescent substrates with good inter-instrument correlation

Rolf Griesser

1994 Williamsburg Conference on Colorimetry of Fluorescent Materials“; English first publication in Color Res. Appl. 19 (1994), 6, p. 446-460

CIE whiteness and tint : possible improvements

R. Griesser

„AIC Interim Meeting ’95 Colorimetry”, Berlin, 4. – 6. September 1995;

first publication (Engl.) Appita 49 (1996), 2, p. 105-112;

https://www.semanticscholar.org/paper/CIE-whiteness-and-tint-%3A-possible-improvements-Griesser/d2a1df7fb5b7b489fecd344c1f6b8025b3a84165?p2df

WHITENESS DETERMINATION OF OPTICALLY BRIGHTENED TEXTILES

R. Hirschler, D.F. Oliveira and A.F. Azevedo

WHITENESS ASSESSMENT OF PAPER SAMPLES AT THE VICINITY OF THE UPPER CIE WHITENESS LIMIT

Coppel L., Lindberg, S., and Rydefalk, S.

STFI-Packforsk, Stockholm, Sweden

Limitations in the efficiency of fluorescent whitening agents in uncoated paper

Ludovic G. Coppel, Mattias Andersson, Per Edström and Jussi Kinnunen

WHITENESS EVALUATIONS ON TINTED AND FWA ADDED PAPERS

Burak Aksoy, Paul D. Fleming* and Margaret K. Joyce

Department of Paper Engineering, Chemical Engineering and Imaging Center for Coating Development
Western Michigan University
Kalamazoo, MI 49008

Comparative Study of Brightness/Whiteness Using Various Analytical Methods on Coated Papers Containing Colorants

Burak Aksoy, Margaret K. Joyce and Paul D. Fleming
Department of Paper and Printing Science and Engineering, Western Michigan University, Kalamazoo, MI, 49008

https://www.researchgate.net/publication/250763960_Comparative_Study_of_BrightnessWhiteness_Using_Various_Analytical_Methods_on_Coated_Papers_Containing_Colorants

Using Optical Brightening Agents (OBA) for Improving the Optical Properties of HYP-Containing Paper Sheets

H. ZhangZ. HeY. Zhou

Published 2009 Materials Science

https://www.semanticscholar.org/paper/Using-Optical-Brightening-Agents-%28OBA%29-for-the-of-Zhang-He/665b2e9c5e7749d54f8904624370945c2e723dd1?p2df

Whiteness and Fluorescence in Layered Paper and Board

Perception and Optical Modelling

L G Coppel

PhD Thesis 2012 Sweden

Influence of SPD on Whiteness value of FWA treated samples

Michal VIK, Martina VIKOVÁ, Aravin Prince PERIYASAMY

https://dspace.vutbr.cz/bitstream/handle/11012/51679/257-vik.pdf?sequence=1

Fluorescence model for multi-layer papers using conventional spectrophotometers

L. G. Coppel, M. Andersson, M. Neuman and P. Edström

https://www.researchgate.net/publication/258551824_Fluorescence_model_for_multi-layer_papers_using_conventional_spectrophotometers

Factors affecting the whiteness of optically brightened material

Juan Lin 1Renzo ShameyDavid Hinks

J Opt Soc Am . 2012 Nov 1; 29 (11): 2289-99.

https://pubmed.ncbi.nlm.nih.gov/23201789/

FLUORESCENCE AND THE PAPER APPEARANCE – CHALLENGES IN PAPER COLORING

Dr. Tarja Shakespeare1, Dr. John Shakespeare

  • June 2009
  • Conference: Papermaking Research Symposium, PRS2009
  • At: Kuopio, Finland

https://www.researchgate.net/publication/328873894_FLUORESCENCE_AND_THE_PAPER_APPEARANCE-CHALLENGES_IN_PAPER_COLORING

A fluorescent extension to the Kubelka–Munk model

Tarja Shakespeare John Shakespeare

First published: 30 December 2002

Col Res Appl, 28, 4–14, 2003

https://onlinelibrary.wiley.com/doi/abs/10.1002/col.10109

Problems in colour measurement of fluorescent paper grades

Tarja Shakespeare John Shakespeare

Analytica Chimica Acta
Volume 380, Issues 2–3, 2 February 1999, Pages 227-242

https://www.sciencedirect.com/science/article/abs/pii/S0003267098004838

Colorant modelling for on-line paper coloring: Evaluations of models and an extension to Kubelka-Munk model 

Show affiliations

  • Shakespeare, Tarja Tuulikki
  • Thesis (PhD). TAMPEREEN TEKNILLINEN KORKEAKOULU (FINLAND), Source DAI-B 61/11, p. 6074, May 2001, 147 pages.

https://www.researchgate.net/publication/234289229_Colorant_modelling_for_on-line_paper_coloring_Evaluations_of_models_and_an_extension_to_Kubelka-Munk_model

Kubelka Munk Model in Paper Optics: Successes, Limitations and Improvements

L. Yang

Progress in Paper Physics Seminar 2011

Conference Proceedings

Editor U. Hirn

Radiative properties of optically thick fluorescent turbid media

Alexander A. Kokhanovsky

Journal of the Optical Society of America A

Vol. 26,Issue 8,pp. 1896-1900(2009)•

https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-26-8-1896

Fluorescent Transfer of Light in Dyed Materials

S. D. Howison and R. J. Lawrence


Read More: https://epubs.siam.org/doi/abs/10.1137/0153026

SIAM J. Appl. Math., 53(2), 447–458. (12 pages)

https://epubs.siam.org/doi/abs/10.1137/0153026

Extension of the Stokes equation for layered constructions to fluorescent turbid media

Ludovic G. Coppel,1,2 Magnus Neuman,2 and Per Edström

1Innventia AB, Box 5604, SE-11486 Stockholm, Sweden

2Department of Natural Sciences, Engineering and Mathematics, Mid Sweden University, SE-87188 Härnösand, Sweden

https://www.researchgate.net/publication/223985363_Extension_of_the_Stokes_equation_for_layered_constructions_to_fluorescent_turbid_media

Influence of Deinked Pulp on Paper Colour and its Susceptibility to Ageing

Ewa Drzewińska

Whiteness Assessment: A Primer

Concepts, Determination and Control of Perceived Whiteness

Dr. Claudio Puebla Axiphos GmbH Germany

The Chemistry and Physics of Special-Effect Pigments and Colorants for Inks and Coatings

Paints and Coatings Industry

2003

https://www.pcimag.com/articles/85016-the-chemistry-and-physics-of-special-effect-pigments-and-colorants-for-inks-and-coatings

Color and Imaging in Digital Video and Cinema

Color reproduction and management is a key task in digital video and cinema production. Choices of hardware, software, and handoffs and handshakes in production process require control over color of an image or a video. This is a very complex task due to several reasons.

  • Complexity of Color and its measurement
  • Changing color and light conditions during shoot indoors and outdoors
  • Hardware and software encoded color standards are inconsistent. Cameras, displays and projectors all have different color specifications.
  • After shoot, the data recorded is processed using different softwares for editing, grading, compositing, CG rendering, animations, and special effects. These softwares require different data formats (Log vs Linear).
  • After processing video data is required to meet different deliverables in multiple formats for displays and projectors.
  • Archiving and storage of data requires specific color formats.
  • There are also subjective and artistic requirements to meet look and feel of the data.

My post is to bring these issues to light and to educate. I hope after reading this post you know little more about color and its management during digital video and cinema production.

Key Terms

  • ACES
  • LUT
  • REC709
  • REC2020
  • Color Gamut
  • CIE Chromaticies
  • CIE XYZ
  • ACES 1.1
  • ACES 1.2
  • Color Workflow
  • Premier Pro
  • Final Cut Pro
  • Davinci Resolve
  • Avid Media Composer
  • IDT
  • ODT
  • RRT
  • Maya
  • Nuke
  • After Effects
  • ITU
  • SMPTE
  • AECS
  • ACES AP0
  • ACES AP1
  • BT 709
  • BT 2020
  • BT 2100 in 2016 to include HDR
  • HDR High Dymanic Range
  • HDR 10
  • SLog3
  • Fusion
  • Resolve
  • After Effects
  • OCIO
  • IDT
  • ODT
  • RRT
  • Red
  • Arri
  • Sony
  • Canon
  • Octane
  • CG
  • Linear representation of light
  • Gamma Curve
  • Log Gamma Curve
  • Log Profiles
  • Dynamic Range
  • Linearize work flow
  • Wide Gamut color space
  • Rendering engines
  • VRay
  • Arnold
  • Redshift
  • Octane
  • Cinema 4d
  • Blender
  • EXR linearize
  • Reference Rendering Transform
  • Color Manager OCIO
  • SLog
  • ACES CC
  • ACES CCT
  • Wave Form
  • DaVinci Resolve
  • After Effects
  • FS7
  • Rushes
  • Academy of Motion Picture Arts and Sciences
  • American Society of Cinematographers ASC
  • Digital Cinema Initiatives DCI
  • Society of Motion Picture and Television Engineers SMPTE
  • OpenColor IO
  • 32 bit per channel
  • 8 Bit
  • ACES CG Input
  • REC 709 Output

Human Vision

Source: https://z-fx.nl/ColorspACES.pdf

Color Models of Human Vision

Please see my two previous posts.

On Light, Vision, Appearance, Color and Imaging

Digital Color and Imaging

Digital Color

Source: What is 4K, UHD, SLog3, Rec 2020

The process of capturing and reproducing images requires a collaboration of camera sensors, file formats, rendering technologies, and display or printer technologies. All of these have different ways and different capabilities of representing color and intensity. In addition, they are all different from how our eyes work which further complicates things. As a result, over the years, several standards and processes have been implemented to accomplish this. They all involve some aspects of how to capture and store colors, what range of colors can be dealt with and how to adjust intensity to best reproduce the real world. To understand the new 4k technologies, including SLOG3, HDR, Rec 2020 etc, an understanding of the following is needed.

  • Gamut
  • Bit Depth
  • Gamma
  • Gamma Correction
  • Color spaces

Color Gamut

Source: https://z-fx.nl/ColorspACES.pdf

Color Capture in Digital Video and Cinema

Source: HOW DOES A DIGITAL CAMERA SENSOR WORK?

A modern digital camera’s sensor comes in one of two varieties generally. It will either be a Complementary Metal Oxide Semiconductor (CMOS), or a Charge-Coupled Device (CCD) sensor. The CCD type is mainly used in older models, but is still used on some modern cameras. Each type has its own advantages and disadvantages, but that is a topic for another article.

The most basic way you can understand how a sensor works is when the shutter opens, the sensor captures the photons that hit it and that is converted to an electrical signal that the processor in the camera reads and interprets as colors. This information is then stitched together to form an image. That is insanely over-simplified though.

The more complex answer is that a sensor is made up of millions of cavities called “photosites,” and these photosites open when the shutter opens and close when the exposure is finished (the number of photosites is the same number of pixels your camera has). The photons that hit each photosite are interpreted as an electrical signal that varies in strength based on how many photons were actually captured in the cavity. How precise this process is depends on your camera’s bit depth.

If we looked at a picture that was taken with just that electrical data mentioned earlier from the sensor, then the images would actually be in gray-scale. How we get colored images is by what’s known as a “Bayer filter array.” A Bayer filter is a colored filter placed over-top of each photosite and is used to determine the color of an image based on how the electrical signals from neighboring photosites measure. The colors of the filters are the standard red, green and blue, with a ratio of one red, one blue and two green in every section of four photosites.

Image for post
A graphic of light entering photosites with Bayer filters layered on. (graphic/Cambridge in Colour)

The red filter allows red light to be captured, the blue allows blue light in and the green allows green light in. The light that doesn’t match that photosites filter is reflected. This means that we are losing two-thirds of the light that can be captured and it is only of one color for each photosite. This forces the camera to guess what the amount of the other two colors is in each given pixel.

The data that is interpreted by the sensor with the Bayer filter array is what a RAW image file is.

The camera then goes through a process to estimate how much of each color of light there was for each photosite and colors the image based on that guessing.

Single Sensor Vs Multiple Sensors in Cameras

  • Sensor Type
    • CCD
    • CMOS
  • Sensor Size
    • Full Frame
    • APS-C
  • Sensor Numbers
    • Single – 1 CMOS or 1CCD
    • Multiple – 2CCD, 3CCD, 3CMOS
  • Sensor Pixels
    • 24 MP
    • 48 MP
  • Sensor Dynamic Range
    • Range of brightness sensor captures
    • 14 Stops
    • 20 Stops

A camera sensor can only capture a limited range of light. When a scene extends beyond that range of light, techniques such as filters, flash, and editing techniques can still create a dramatic, well-detailed image.

Comparison of different sensor sizes

Image Source: Camera Sensor Sizes Explained: What You Need to Know

Source: Camera Sensor Sizes Explained: What You Need to Know

Cameras with Single Image Sensor

With CFA Color Filter Array

  • Bayer CFA

Bayer CFA

Source:

Conversion of RAW files

Source: https://z-fx.nl/ColorspACES.pdf

Cameras with multiple Image Sensors

Cameras with multiple sensors do not require Bayer CFA.

  • 3 CCD – Single color info per sensor
  • 3 CMOS – Single color info per sensor
  • 4 CCD – Single color info per sensor plus Near Infra Red (NIR) info

Color Spaces in the Digital Video and Cinema

Image Source: Common Color Spaces

Gamut of Color Spaces

Color Space is characterized based on how much of its gamut covers the CIE Chromaticity Diagram.

Image Source: Why Every Editor, Colorist, and VFX Artist Needs to Understand ACES

Source: The Pointer’s Gamut
The coverage of real surface colors by RGB color spaces and wide gamut displays

Source: The Pointer’s Gamut
The coverage of real surface colors by RGB color spaces and wide gamut displays

Device Dependent Color Spaces

Capture Devices

Professional Cameras for Cinematography and Videography from

  • Sony
  • Canon
  • Arri
  • Red

Camera Sensor Dynamic Range

Image Source: Understanding 4K, Ultra HD and HDR

Conversion of RAW to Video Formats

Image Source: Understanding 4K, Ultra HD and HDR

Sony SLog Transfer Function

Image Source: Understanding 4K, Ultra HD and HDR

Sony Transfer Functions

Image Source: Understanding 4K, Ultra HD and HDR

Other Transfer Functions

Image Source: Understanding 4K, Ultra HD and HDR

Sony Color Spaces

Image Source: Understanding 4K, Ultra HD and HDR

Slog, Gamma, and Gamut

Source: Are S-Log and Color Space separate things?

S-log is a specific gamma, color space is a general term referring to gamuts. A very crude way of thinking is gamma refers to brightness and gamut refers to color.

It’s important to know which gamma and gamut you are recording in as this helps to ensure there is correct gamma and gamut mapping from capture to exhibition.

What is Gamma?

Gamma is also called Tone Mapping.

Source: What is 4K, UHD, SLog3, Rec 2020

Each pixel has a brightness level, which is the average of {red, green, blue} values, and this is called its luminance. In order to reproduce an image from capture to display, the luminance needs to be accurately reproduced. Since sensors and displays can have different luminance characteristics, there needs to be a mapping or relationship between a pixel’s numerical values and the actual luminance…this relationship is called the Gamma.

Linear Space is counter to Gamma Space or Log Space.

Log Space or Gamma Space

Log Curve simulates a non-linear curve. Log Color Profiles can be created for a camera.

  • Arri LogC
  • Cineon Dpx
  • RedLogFilm
  • Canon-Log

Source: LOG COLOR IN-DEPTH

Every professional camera manufacturer and almost every VFX and grading package has a Log workflow. Camera companies such as Arri, Sony, Canon, Red and many others implement their own flavors of Log color space. With the Log workflow it is possible to fit more dynamic range into an image and simulate nonlinear film response to light. The term Log is derived from the word logarithm, which is a fancy name for a function which outputs exponents for the given number.

Log Spaces of Different Brands

Source: LOG COLOR IN-DEPTH

Gamma Curve = Tone Curve = Log Curve

Log footage is an important part of the post-production workflow. Here’s what you need to know.

Source: UNDERSTANDING LOG AND COLOR SPACE IN COMPOSITING

As digital filmmaking becomes more and more affordable, technologies become increasingly available to colorists or post-production professionals. In this case, Log footage. The Log (logarithmic) color space has been around for quite a while. Initially high-end post houses used it with scanned film negatives in a color space called Cineon Log. Now, pretty much all camera manufacturers offer their own Log curve (or multiple). There is S-Log 2&3 (Sony), LogC (Arri), Canon LogV-Log (panasonic), Red LogfilmBlackmagic Log, etc. Each of them are different, usually tailored for the color science of the particular manufacturer’s products.

The biggest reason to use the Log color curve is how it retains the most dynamic range of information from the camera sensor (or film negative). It encodes what the camera sees logarithmically, meaning that the correlation between the exposure of the image (measured in stops) and the recorded image  is completely constant over a wider range. It utilizes more of the sensor’s information than a standard video curve because it’s saving as much data as possible rather than capturing specifically for the human eye or a video screen. This gives you much more color data to work with in post-production.

Linear Space

Source: Color Management/Blender

For correct results, different Color Spaces are needed for rendering, display and storage of images. Rendering and compositing is best done in scene linear color space, which corresponds more closely to nature, and makes computations more physically accurate.

Log Space to Linear Space Conversion

Source: LOG COLOR IN-DEPTH

In conclusion, to bring an image into the log color space all we need to do is to apply a logarithmic function which transforms values of pixels based on the log curves above. To linearize a log picture, we use an exponent function. Since the log color space is a mathematical transformation of values of pixels, it can be used with any types of file format, bit depth and channel. 

White Point

Is the color temperature of light. Outdoors, Indoor, Sunny, Cloudy conditions affect White Point. In Cameras white point can be adjusted depending on light conditions. D65 simulates daylight.

  • D50 – 5000 K
  • D60 – 6000 K
  • D65 – 6500 K

sRGB uses D65 vs ACES uses D60.

Source: https://z-fx.nl/ColorspACES.pdf

So do you understand these now?

  • LUT (Look Up Tables)
  • EOTF (Electro-Optical Transfer Function) – Linear to Non Linear or Log Conversion
  • OETF (Optio-Electro Transfer Function) – Log to Linear Conversion
  • Gamma Curve – Popular Name for EOTF
  • Gamma Correction
  • Log Curve (Non Linear Data)
  • Linear Curve (Linear Data)
  • High Dynamic Range HDR
  • Standard Dynamic Range SDR
  • White Point
  • IDT – Input Data Transform
  • ODT – Output Data Transform
  • Log LUT
  • f-Stops

A pair of Gamma and Gamut data is requied for encoding to display colors.

A device dependent RGB color space has standard primaries, gamma, and a whitepoint such as D50 or D65.

  • Primaries (R G B) for Color
  • Gamma for Luminance, and
  • White Point

Source: The Essential Guide to Color Spaces

Now that we’ve discussed these three parameters, here are some practical examples:

An Arri Alexa records media in Arri Wide Color Gamut, with an Arri Log C tone mapping curve, and a white point ranging from 2,000K to 11,000K.

A RED Dragon captures media in RedWideGamutRGB gamut, with a Log3G10 tone mapping curve, and a white point ranging from 1,700K to 10,000K (other gamut and gamma choices are available).

A cinema projector has a DCI-P3 gamut, a Gamma 2.6 tone mapping curve, and a standard illuminant D63 white point.

An SDR TV has a Rec 709 gamut, a Gamma 2.4 tone mapping curve, and a standard illuminant D65 white point.

Display Devices

  • Display Projectors
  • Television
  • Computer Monitors

Three advantages in newer display devices

  • Color
    • Color Space
    • Bit Depth
    • Gamma
    • Gamma Correction
  • Resolution
    • 4K vs 8K
  • Luminance
    • Nits

Image Source: What is 4K, UHD, SLog3, Rec 2020

Color Spaces used in Display Devices

Image Source: What is 4K, UHD, SLog3, Rec 2020

Display Resolution

Image Source: WHAT IS 4K, UHD, SLOG3, REC 2020

Bit Depth

Image Source: WHAT IS 4K, UHD, SLOG3, REC 2020

Color Specification using Color Management option in displays

Color Management in Digital Video and Cinema Production

In production of

  • Feature Film
  • Television
  • OTT
  • Live Production

SDR with REC 709 Color Space

Image Source: Understanding 4K, Ultra HD and HDR

SDR with S-Gamut3 and REC 2020

Image Source: Understanding 4K, Ultra HD and HDR

Process Flow

Image Source: Understanding 4K, Ultra HD and HDR

Live Production

Image Source: Understanding 4K, Ultra HD and HDR

Image Source: WHAT IS 4K, UHD, SLOG3, REC 2020

Operations during Production Process
  • Shoot
  • Convert
  • Edit/Grading
  • Conforming
  • Compositing/Rendering/VFX/CG
  • Convert
  • Deliverables
Color Space Hierarchy in Process Flows

  • Scene Referred – Input data has higher priority
  • Display Referred – Output data has higher priority

Source: https://z-fx.nl/ColorspACES.pdf

Source:

Process Flows in ACES

Source: https://z-fx.nl/ColorspACES.pdf

Source: https://z-fx.nl/ColorspACES.pdf

Working with ACES

Source: https://z-fx.nl/ColorspACES.pdf

CG and VFX Process Flows

Source: https://z-fx.nl/ColorspACES.pdf

The ‘Parts’ Of ACES

Source: Why Every Editor, Colorist, and VFX Artist Needs to Understand ACES

Even though ACES and its various transforms are quite mathematically complex, you can understand ACES better by understanding what each part or transform in the pipeline does.

Here’s the terminology for each of these transforms:

ACES Input Transform (aka: IDT or Input Device Transform)

The Input Transform takes the capture-referred data of a camera and transforms it into scene linear, ACES color space. Camera manufacturers are responsible for developing IDTs for their cameras but the Academy tests and verifies the IDTs. In future versions of ACES, the Academy may take on more control in the development of IDTs. IDTs, like all ACES transforms, are written using the CTL (Color Transform Language) programming language. It’s also possible to utilize different IDTs to compensate for different camera settings that might have been used.

ACES Look Transform (aka: LMT or Look Modification Transform)

The first part of what’s known as the ACES Viewing Transform (the Viewing Transform is a combination of LMT, RRT, & ODT transforms). LMTs provide a way to apply a look in a similar way to a Look Up Table (LUT). It’s important to note that the LMT happens after color grading of ACES data. Also, not every tool supports the use of LMTs.

RRT (Reference Rendering Transform)

Think of the RRT as the render engine component of ACES. The RRT converts scene referred linear data to an ultrawide display-referred data set. The RRT works in combo with the ODT to create viewable data for displays and projectors. While the Academy publishes the standard RRT, some applications have the ability to use customized RRTs (written with CTL). But many color correction systems do not provide direct access to the RRT.

ACES Output Transform (also known as the ODT or Output Device Transform)

The final step in the ACES processing pipeline is the ODT. This takes the high dynamic range data from the RRT and transforms it for different devices and color spaces. Like P3 or Rec 709, 2020, etc. Like IDTs and RRTs, ODTs are written with CTL.

Derivative Standards

Source: Why Every Editor, Colorist, and VFX Artist Needs to Understand ACES

There are also three main subsets of ACES used for finishing workflows called ACEScc, ACEScct and ACEScg:

  • ACEScc uses logarithmic color encoding and has the advantage of making color grading tools feel much more like they do when working in a log space that many colorists prefer.
  • ACEScct is just like ACEScc, but adds a ‘toe’ to the encoding. This means that lift operations respond similarly to traditional log film scans. This quasi-logarithmic behavior is described as being more milky, or foggier. ACEScct was added with the ACES 1.03 specification. It’s meant as an alternative to ACEScc based on the feedback of many colorists.
  • ACEScg utilizes linear color encoding and is designed for VFX/CGI artists so their tools behave more traditionally.

The ACES Pipeline

Source: Why Every Editor, Colorist, and VFX Artist Needs to Understand ACES

Now that we’ve defined the transforms used for ACES, understanding how the various transforms combine to form an ACES processing pipeline is pretty straightforward:

Camera Data -> Input Transform -> Color Grading -> Look Transform (optional) -> Reference Rendering Transform -> Output Transform

As mentioned, ACES is a hybrid color management system of scene referred/scene linear and display referred data.

Source: Why Every Editor, Colorist, and VFX Artist Needs to Understand ACES

Source: COLOUR MANAGEMENT BASICS

Source: COLOUR MANAGEMENT BASICS

Source: COLOUR MANAGEMENT BASICS

Source: COLOUR MANAGEMENT BASICS/Autodesk

Color Throttle

Because of bottlenecks in hardware and software, the color captured during the image/video capture process does not flow in its entirty to the displays of the users. Use of hardware and color spaces used during production process determines the output displayed. Color is thus throttled.

Color Throttle when using REC 709 Color Space

Image Source: BT.2020: How the Newest Color Range Standard Maximizes 4K Video Quality

Color Throttle when using REC 2020 Color Space

Image Source: BT.2020: How the Newest Color Range Standard Maximizes 4K Video Quality

Human Visual Dynamic Range Vs REC 2020 Range

Source: BT.2020: How the Newest Color Range Standard Maximizes 4K Video Quality

Source:

Softwares used in Post Production in Digital Video and Cinema

Source: digitalfilmpro.com

Video Editing Software and Hardware
  • Non Linear Editor
    • Avid Media Composer
    • Adobe Premiere Pro
    • Final Cut Pro
    • DaVinci Resolve – color correction plus NLE
    • Vegas Pro
  • Digital Audio Workstation
    • Avid Pro Tools
    • Apple Logic Pro X
    • Ableton Live 9
    • Cakewalk Sonar
    • Adobe Audition
  • Close-Captioning and Subtitling
    • Aegisub
    • NLEs
  • Edit Workstation
    • Edit Computer
    • Audio Equipment
    • File Sharing
      • KVM Extender
    • Editing Keyboard
    • Desk Chair
  • Digital Audio Transcipts

Creative Apps
  • RV
  • Adobe After Effects
  • Adobe Premiere Pro
  • SideFX Houdini
  • Unreal Engine
  • Unity
  • Perforce Helix Core
  • Adobe Creative Cloud
  • Adobe Illustrator
  • Autodesk 3DS Max
  • Autodesk Maya
  • Autodesk RV
  • Cinesync
  • Connect
  • Deadline
  • Foundry Hiero
  • Foundry Hiero Player
  • Foundry Nuke
  • Foundry Nuke Studio
  • Maxon Cinema 4D

Free Video Editing Tools
  • DaVinci Resolve
  • Lightworks
  • HitFilm Express
  • Avid Media Composer First
  • iMovie

Free Video Production Software Tools
  • Audacity – multitrack audio recorder
  • Ardour – DAW
  • GIMP- image editing
  • Blender – 3D Creation
  • Nuke Studio – Compositor – Node Based visual FX (VFX), editing, and finishing Studio
  • Blackmagic Fusion – Full feaured Compositor – Motion Graphics

3D Rendering Softwares
  • Unity
  • 3Ds Max Design
  • Maya
  • Cinema 4D
  • Blender
  • Keyshot
  • V-Ray
  • Lumion
  • SOLIDWORKS Visualize
  • Direct 3D
  • RenderMan
  • Redshift
  • Octane Render
  • Arnold
  • Maxwell
Color Management in Applications

Source: DISPLAY CALIBRATION & COLOR MANAGEMENT

Cameras for Video

Budget Cinema Cameras
  • Black Magic Pocket Cinema Camera
  • Black Magic Pocket Camera 4K
  • Z Cam E2C 4K Cine Camera MFT
  • Panasonic GH5

Best Cameras for Videographers

Source: Best cameras for videographers/DPREVIEW.COM

Published Nov 24, 2020

  • Panasonic Lumix DC – S1H
  • Panasonic Lumix DC-GH5
  • Canon EOS R6
  • Fujifilm X-T4
  • Nikon Z6
  • Nikon Z6 II
  • Panasonic Lumix Dc-GH5S
  • Sigma fp
  • Sony a7S III

Best 4K and 6K Cameras for Film making

Source: https://www.youtube.com/watch?v=o0muduTpveM&t=244s

  • Sony Alpha a7 III
  • Panasonic Lumix GH5S
  • Sony PXW FSM2
  • Panasonic Lumix S1H
  • Blackmagic Pocket Cinema 6K
  • Canon EOS C300 Mark II
  • Panasonic AU-EVA1
  • Blackmagic Design URSA Mini Pro G2
  • Sony PXW FS9
  • Canon C500 Mark II

Best Camcorders for Videographers

Source: Youtube

  • Panasonic HC-X2000
  • Sony PXW-Z280
  • Canon XA55
  • Panasonic AG-CX10
  • JVC GY-HC500U
  • Sony PXW-Z90
  • Panasonic HC-X1
  • Canon XF 705
  • JVC GY-HM250
  • Sony FDR -AX700

My Related Posts

Digital Color and Imaging

On Light, Vision, Appearance, Color and Imaging

Key Sources of Research

Why Every Editor, Colorist, and VFX Artist Needs to Understand ACES

Working with ACES in DaVinci Resolve

Oliver Peters

https://digitalfilms.wordpress.com/2020/10/02/working-with-aces-in-davinci-resolve/

Color Management and ACES Workflow

CG Cinematography

The Pointer’s Gamut
The coverage of real surface colors by RGB color spaces and wide gamut displays

Kid Jansen, Updated 19 February 2014

https://www.tftcentral.co.uk/articles/pointers_gamut.htm

ACES: Where Are We Now?

by Geoff Smith on August 14, 2020

https://www.abelcine.com/articles/blog-and-knowledge/tutorials-and-guides/aces-where-are-we-now

What is 4K, UHD, SLog3, Rec 2020

And other really boring things.

Compiled By Peter Morrone

BT.2020: How the Newest Color Range Standard Maximizes 4K Video Quality

BenQ

2020/05/29

https://www.benq.com/en-us/knowledge-center/knowledge/bt2020.html

Color Spaces in Visual Effects

Color Spaces

February 15, 2019

https://ciechanow.ski/color-spaces/

Chapter 1 Color Management

Color Spaces / MAYA/Autodesk

https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2020/ENU/Maya-Rendering/files/GUID-4410C27C-BB49-491B-AD13-14F48A8CCAAE-htm.html

Elle Stone’s Well-Behaved ICC Profiles and Code

https://ninedegreesbelow.com/photography/lcms-make-icc-profiles.html

ACES Workflow

Common Color Spaces

Color for Motion Pictures and Games

From Design to Display
  • Haarm-Pieter Duiker
  • Alex Forsythe
  • Stefan Luka
  • Thomas Mansencal
  • Jeremy Selan
  • Kevin Shaw
  • Nick Shaw

A VES Technology Committee White Paper
2019

https://nick-shaw.github.io/cinematiccolor/common-rgb-color-spaces.html

Cinematic Color From Your Monitor to the Big Screen

A VES Technology Committee White Paper Oct 17, 2012

Color Enhancement and Rendering in Film and Game Production: Color Management

Joseph Goldstone Lilliputian Pictures LLC

COLOR CORRECTION HANDBOOK:
Professional Techniques for Video and Cinema

Second Edition 

Alexis Van Hurkman

Peachpit Press http://www.peachpit.com

Colour Appearance Issues in Digital Video, HD/UHD, and D‐cinema

Charles Poynton

Understanding Color Management,

Second Edition

First published:18 July 2018

https://onlinelibrary.wiley.com/doi/book/10.1002/9781119223702

COLOR MANAGEMENT WITH CINEMA

Red

https://www.red.com/red-101/cinema-color-management

Digital Color Management

Encoding Solutions

Giorgianni, Edward J / Madden, Thomas E

The Basics of High Dynamic Range Media Explained [u]

Posted on July 27, 2019 by Larry

Understanding 4K, Ultra HD and HDR

Sony

COLOUR REPRODUCTION IN ELECTRONIC IMAGING SYSTEMS

PHOTOGRAPHY, TELEVISION, CINEMATOGRAPHY

Michael S Tooms

Digital Camera Reviews and Sensor Performance Summary

by Roger N. Clark

https://clarkvision.com/imagedetail/digital.sensor.performance.summary/

How to Use Dynamic Range for Stunning Photos in Bright Light

2 CCD , 3 CCD cameras, 4 CCD and 3 CMOS Cameras

http://www.adept.net.au/cameras/2CCD_3CCD_Cameras.shtml

CCD Sensors, Albert Einstein, and the Photoelectric Effect

https://www.radiantvisionsystems.com/blog/ccd-sensors-albert-einstein-and-photoelectric-effect

Color Management for Photographers – A Simplified Guide

Camera Sensor Sizes Explained: What You Need to Know

https://www.studiobinder.com/blog/camera-sensor-size/

Reading 15: Color

http://web.mit.edu/6.813/www/sp18/classes/15-color/

The Fundamentals of Camera and Image Sensor Technology

Jon Chouinard

Understanding color & the in-camera image processing pipeline for computer vision

Dr. Michael S. Brown

Digital Image Sensors

https://www.sensorland.com/HowPage090.html

Color Spaces, Log and Gamma

3.4 Color Spaces, Log and Gamma

LOG COLOR IN-DEPTH

Renderstory

Exploring the Basic Concepts of HDR: Dynamic Range, Gamma Curves, and Wide Color Gamut

Abhay Sharma

https://onlinelibrary.wiley.com/doi/pdf/10.1002/msid.1060

Understanding RGB Color Spaces for Monitors, Projectors, and Televisions

Abhay Sharma

First published: 26 March 2019

https://onlinelibrary.wiley.com/doi/full/10.1002/msid.1020

UHDTV – HDR and WCG

Understanding UHDTV Displays with PQ/HLG HDR, and WCG

https://www.lightspace.lightillusion.com/uhdtv.html

Color Management

https://docs.blender.org/manual/en/latest/render/color_management.html

Color Space Management: sRGB, Linear and Log

https://tiberius-viris.artstation.com/blog/3ZBO/color-space-management-srgb-linear-and-log

GAMMA AND LINEAR SPACE – WHAT THEY ARE AND HOW THEY DIFFER

https://www.kinematicsoup.com/news/2016/6/15/gamma-and-linear-space-what-they-are-how-they-differ

Are S-Log and Color Space separate things?

Understanding Log and Color Space In Compositing

RENDER COLOR SPACES

23 JUNE 2016

Anders Langlands

https://www.colour-science.org/anders-langlands/

Understanding High Dynamic Range (HDR) Imaging by Curtis Clark, ASC 

A Cinematographer Perspective

https://cms-assets.theasc.com/curtis-clark-asc-understanding-high-dynamic-range.pdf?mtime=20180502122857

Color Science Fundamentals in Motion Imaging

March 14, 2019 01:00 PM

https://www.smpte.org/events/color-science-fundamentals-in-motion-imaging

What is RAW Development?

Colour Management Basics

Autodesk Feb 2020

The Best Rendering Software for CG Lighting for Animation

by Tina Lee | Feb 14, 2019

C. A. Bouman: Digital Image Processing

January 7, 2020

The Essential Guide to Color Spaces

Cullen Kelly

Dell Color Management Software

User Manual

Adjusting for the Scene Adopted White

White Point Conversion

https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2016/ENU/Maya/files/GUID-2C925F6A-5A9C-4B2B-B732-90F4C3D2EB49-htm.html

A Complex Color Management Example

https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2016/ENU/Maya/files/GUID-7D579180-1E60-43DD-BB9C-0C00D1968F53-htm.html

Common Color Management Scenarios

https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2016/ENU/Maya/files/GUID-B2CD60E0-C100-45A4-9595-84D2DF98B268-htm.html

A Conversation about White Point and Digital Displays [Interview]

https://www.nanolumens.com/blog/an-imaginary-conversation-about-white-point-and-digital-displays/

Gamma and White Point Explained: How to Calibrate Your Monitor

https://blogs.scientificamerican.com/symbiartic/how-to-calibrate-your-monitor/

Why is the media white point of a display profile always D50?

http://www.color.org/whyd50.xalter

Colour Management for Video Editors

Display Calibration & Color Management

https://www.mysterybox.us/blog/2017/9/7/display-calibration-color-management

Color Communication

How does a digital camera sensor work?

Digital Color and Imaging

Digital Color and Imaging

In my previous post, I focused on Industrial Color Technology as used in Process Industries such as Paint, Plastics, Textiles, Paper, and Printing.

There are several useful links in the references section to color introduction which will be beneficial to people interested in digital colors and imaging.

On Light, Vision, Appearance, Color and Imaging

In this post, I have focused on another aspect of color technology as used in Digital Technology and Graphics Arts and Design Industry.

Devices for Digital Color and Imaging

  • Inkjet and Laser Printers
  • Displays on Desktop Computers and Mobile Devices
  • Television
  • Digital Cameras/Photography
  • Digital Video

Color Models

Not all color models listed below are device independent.

They represent human vision. These are international standards of color measurement. They were developed at diffrent times and are refinements on older models to mimic human vision and visual perception.

Image Source: COLOR PART 1: CIE CHROMATICITY AND PERCEPTION

RGB VS CMY Color Models

Image Source: BASICS OF COLOR IMAGING

List of Color Models

  • CIE x,y,Y
  • CIEXYZ
  • CIELAB
  • CIELCH
  • CIELUV
  • RGB
  • CMYK
  • HSB
  • HSV
  • HSL
  • HSI
  • YUV
  • YIQ
  • YCbCr
  • YPbPr

Color Models Classification

Image Source: UNDERSTANDING COLOR MODELS: A REVIEW

Uses of Color Models

Image Source: UNDERSTANDING COLOR MODELS: A REVIEW

Color Models Taxonomy

Image Source: UNDERSTANDING COLOR MODELS: A REVIEW

Image Source: COLOR IMAGES, COLOR SPACES AND COLOR IMAGE PROCESSING

Spot Colors Color Spaces

These color systems are used in Spot Printing in commercial printing applications.

  • ANPA
  • Colour Index International
  • DIC
  • PMS
  • FOCOLTONE
  • HKS
  • Munsell
  • NCS
  • Pantone
  • RAL
  • TOYO
  • Truematch

Image Source: A PRIMER TO COLORS IN DIGITAL DESIGN

Color Spaces

Are device dependent color models.

  • Adobe RGB 1998
  • sRGB
  • Apple RGB
  • ProPHOTO
  • Wide Gamut RGB
  • DCI-P3 or Display P3
  • P3 D65
  • P3 Theatrical
  • EBU Tech. 3213-E (Supersedes PAL)
  • oRGB
  • ECI RGB V2
  • ColorMatch RGB
  • Rec 2020
  • SWOP CMYK
  • HDTV RGB
  • NTSC RGB
  • CIE RGB
  • SGI RGB
  • PAL/SECAM RGB
  • SMPTE-240M RGB
  • SMPTE-C RGB
  • ACES RGB
  • Rec. 709 (ITU-R BT. 709)
  • Photo RGB
  • DCI-P3Pro
  • REC 209
  • scRGB
  • ROMM RGB
  • Arri LogC
  • RedWideGamutRGB
  • Bruce RGB
  • Ekta Space PS5
  • Don RGB 4
  • Beta RGB
  • Best RGB
  • Max RGB
  • Xtreme RGB
  • Ma RGBta

List of Color Spaces available in PhotoShop

Image Source: WHICH IS THE BEST COLOR SPACE FOR PHOTOGRAPHY: SRGB OR ADOBE RGB?

List of Color Spaces used in Videos/Cinema

Image Source: COMMON RGB COLOR SPACES

Color Gamut

Is range of color. Defines boundaries of color space. Number of Hues will be higher in a larger color gamut color space.

A color gamut is the defining a range of chromaticities—essentially a set of possible hues and their respective maximum saturations.

Image Source: UNDERSTANDING COLOR SPACE

Image Source: Beginner’s Guide to Color Space: RGB, CMYK, and Pantone

Color Management

Color spaces are used in

  • Capture of images, videos and Cinema
  • Editing and Processing of Images and Videos
  • Visual Displays on Computer Monitors, Phone and Tablet Displays, Digital Camera Displays, Digital Video Displays, Television, Cinema Screens, and LCD screens on Auto and Home appliances.
  • Printing of Images on Ink Jet printers, Laser printers, Screen Printing, Offset Printing etc.

Flows of Images from

  • Capture to Editing
  • Editing to Viewing on Media Devices
  • Editing to Printing on Media
  • Editing to Storage on Media Devices

Image Source: COLOR SPACE

Color Spaces used for different stages of the process

  • Capture – For Stills – Adobe RGB, sRGB; For Video -YUV
  • Editing – ProPhoto, Adobe RGB, sRGB, CIEXYZ, YUV
  • Viewing – sRGB
  • Printing – CMYK
  • Storage – sRGB, Adobe RGB, YUV, CMYK

Color Profiles

Color profiles define the specific color space (e.g. Adobe RGB) of a document or device. The terms color profile and color space are often used interchangeably.

Image Source: Digital Color Workflows and the
HP DreamColor LP2480zx Professional LCD Display

Please see the link below to learn about embedded color profiles. Since Color spaces are different, the tagged color profile is required for uniformity of image across different color spaces.

Color Filters

  • Bayer Array
  • Foveon X3

Source: COLOR FILTER ARRAY/Wikipedia

Color filters are needed because the typical photosensors detect light intensity with little or no wavelength specificity, and therefore cannot separate color information.[1] Since sensors are made of semiconductors they obey solid-state physics.

The color filters filter the light by wavelength range, such that the separate filtered intensities include information about the color of light. For example, the Bayer filter (shown to the right) gives information about the intensity of light in red, green, and blue (RGB) wavelength regions. The raw image data captured by the image sensor is then converted to a full-color image (with intensities of all three primary colors represented at each pixel) by a demosaicing algorithm which is tailored for each type of color filter. The spectral transmittance of the CFA elements along with the demosaicing algorithm jointly determine the color rendition.[2] The sensor’s passband quantum efficiency and span of the CFA’s spectral responses are typically wider than the visible spectrum, thus all visible colors can be distinguished. The responses of the filters do not generally correspond to the CIE color matching functions,[3] so a color translation is required to convert the tristimulus values into a common, absolute color space.[4]

Source: COLOR FILTER ARRAY/Wikipedia

Color BIT Depth

Defines details of a color image. More bit depth means more data storage per pixel of screen.

Color Gamut and Bit Depth defines color of an image.

What color Gamut was used and what bit depth was used in creating, editing, viewing, printing, and storing of an image?

Source: Human Vision and Digital Color Perception

The bit depth is what determines the color information of a digital image. The more bits stored in a pixel, the more information is stored and the greater the detail in color. The following is a guide of how many colors can be represented based on the number of bits.

1 Bit — 2 colors (Monochrome)
8 Bit — 256 colors (Low Color)
16 Bit — 65536 colors (High Color)
24 Bit — 16777216 colors (True Color)

Image Source: INTRODUCTION TO BASIC MEASURES OF A DIGITAL IMAGE FOR PICTORIAL COLLECTIONS

Rendering Intent

Image Source: A Breakdown Of Color Spaces | You Really Should Have A Grasp On This

Image Source: Choosing a color space: sRGB, Adobe RGB and ProPhoto RGB

Image Format during Image Capture

  • RAW
  • JPEG
  • JPEG2000

Using Color Filter Array, the color data is captured in RAW form. It then is converted to JPEG image file format.

Image Source: UNDERSTANDING DIGITAL RAW CAPTURE

Process Flows In Digital Color Imaging System

Image Source: SYSTEM OPTIMIZATION IN DIGITAL COLOR IMAGING

Digital Color Terminology

Image Source:

My Related Posts

On Light, Vision, Appearance, Color and Imaging

Key Sources of Research

Basics of Color Imaging

Yao Wang

Introduction to Color Imaging Science

HSIEN-CHE LEE

Digital Color Imaging

Gaurav Sharma, Member, IEEE, and H. Joel Trussell, Fellow, IEEE

Digital Color Imaging Handbook

Edited By Gaurav Sharma, Gaurav Sharma, Raja Bala

https://www.taylorfrancis.com/books/e/9781315220086/chapters/10.1201/9781420041484-1

HUMAN VISION AND DIGITAL COLOR PERCEPTION

Vince Tabora

HD Pro Blog

Medium.com

Understanding Chroma And Luminance In Digital Imaging

Vince Tabora

HD PRO

Medium.com

THE DIFFERENCE BETWEEN CMYK AND RGB IN DIGITAL PRINTING

https://www.decalimpressions.com/company-info/blog.html/article/2018/06/05/the-difference-between-cmyk-and-rgb-in-digital-printing

Some Common RGB Working Space Matrices

http://brucelindbloom.com/index.html?Eqn_RGB_XYZ_Matrix.html

Color Part 1:
CIE Chromaticity and Perception 

by Roger N. Clark

https://clarkvision.com/articles/color-cie-chromaticity-and-perception/

A Primer to Colors in Digital Design

Archit Jha

https://uxdesign.cc/a-primer-to-colors-in-digital-design-7d16bb33399e

Digital Color Workflows and the
HP DreamColor LP2480zx Professional LCD Display

RGB color space profiles

http://www.hutchcolor.com/profiles.html#freeRGBspaces

Video Colour Color Space for photographers

http://www.jamesmilnersmyth.com/video-colour-color-space-for-photographers/

Understanding Color Space

https://stephaniebryanphoto.com/myblog/understanding-color-space

Choosing a color space: sRGB, Adobe RGB and ProPhoto RGB

Information on Color Spaces and Rendering Intent

Canon

Understanding Color Models Used in Digital Image Processing

https://www.allaboutcircuits.com/technical-articleUnderstanding Color Models Used in Digital Image Processings/understanding-color-models-used-in-digital-image-processing/

Which is the Best Color Space for Photography: sRGB or Adobe RGB?

https://contrastly.com/which-is-the-best-color-space-for-photography-srgb-or-adobe-rgb/

How to Choose the Right Video Color Space

http://www.cinematiccolor.com/

Color Models

http://cs.brown.edu/courses/cs092/VA10/HTML/ColorModels.html

Color Space Mismatches

Colour Space Conversions

Adrian Ford (ajoec1@wmin.ac.uk <defunct>) and Alan Roberts (Alan.Roberts@rd.bbc.co.uk).

August 11, 1998(a)

UNDERSTANDING COLOR SPACES

Unraval

https://www.unravel.com.au/understanding-color-spaces

ColorPerfect, ColorNeg et al. and RGB / grayscale working spaces

https://www.colorperfect.com/working_spaces.html?lang=en

Color Space Names

Apple

https://developer.apple.com/documentation/coregraphics/cgcolorspace/color_space_names

History of the Very Odd sRGB Color Space

https://ninedegreesbelow.com/photography/srgb-history.html

color images, color spaces and color image processing

Ole-Johan Skrede 08.03.2017

INF2310 – Digital Image Processing

Department of Informatics
The Faculty of Mathematics and Natural Sciences University of Oslo

The Reversibility of Six Geometric Color Spaces

Tian-YuanShih

A Review of RGB Color Spaces

Beginner’s Guide to Color Space: RGB, CMYK, and Pantone

Color spaces, profiles and color management explained

https://lifeafterphotoshop.com/color-spaces-profiles-and-color-management-explained/

color space

PC Magazine

https://www.pcmag.com/encyclopedia/term/color-space

Digital-Image Color Spaces

Jeffrey Friedl’s Blog

Color Spaces and Digital Imaging

Higham, Nicholas J. 2015

The Essential Guide to Color Spaces

Cullen Kelly

Mathematical Representation of Color Spaces and Its Role in Communication Systems

Riyadh M. Al-saleem ,1 Baraa M. Al-Hilali ,2 and Izz K. Abboud

https://www.hindawi.com/journals/jam/2020/4640175/

Color Spaces and Color Profiles

https://www.dpbestflow.org/color/color-space-and-color-profiles

Good One

Commercial Printing

https://www.dpbestflow.org/color/commercial-printing

https://www.dpbestflow.org/links/31

Color Management Overview

https://www.dpbestflow.org/node/247

Describing, Specifying, and Using Digital Digital Color Space

NOVEMBER 18, 2002 

https://www.screenweb.com/content/describing-specifying-and-using-digital-digital-color-space

Introduction to Light, Color and Color Space

https://www.scratchapixel.com/lessons/digital-imaging/colors/color-space

The Color Space Conundrum

https://theasc.com/magazine/jan05/conundrum/index.html

A Breakdown Of Color Spaces | You Really Should Have A Grasp On This

A Standard Default Color Space for the Internet – sRGB

Michael Stokes (Hewlett-Packard), Matthew Anderson (Microsoft), 

Srinivasan Chandrasekar (Microsoft), Ricardo Motta (Hewlett-Packard)

Version 1.10, November 5, 1996

https://www.w3.org/Graphics/Color/sRGB.html

Color Models

https://scc.ustc.edu.cn/zlsc/sugon/intel/ipp/ipp_manual/IPPI/ippi_ch6/ch6_color_models.htm

COLOR SCIENCE AND COLOR APPEARANCE MODELS FOR CG, HDTV, AND D-CINEMA

Authors:
Charles A Poynton
Garrett M Johnson
Publication: SIGGRAPH ’04: ACM SIGGRAPH 2004 Course NotesAugust 2004

Color in Information Display Principles, Perception, and Models

Maureen C. Stone

StoneSoup Consulting

Course 20 SIGGRAPH 2004

oRGB: A Practical Opponent Color Space for Computer Graphics

Margarita Bratkova∗ Solomon Boulos† Peter Shirley‡ University of Utah

Color in Science, Art and Industry: The Inter-Society Color Council 75th Anniversary CD

ISCC

Image Processing 101

Color Theory Color Models

http://www.pengadprinting.com/content/color-theory-part-ii-types-color-and-uses-0

Color Models (RGB vs CMYK)

Understanding Color Models: A Review

1 Noor A. Ibraheem, 2 Mokhtar M. Hasan, 3 Rafiqul Z. Khan, 4 Pramod K. Mishra
1 Department of Computer Science, Faculty of Science, Aligarh Muslim University, Uttar Pradesh, India

Color Theory

Colorotate

RGB vs HSB vs HSL - Demystified

Anagh Sharma

https://www.anaghsharma.com/blog/rgb-vs-hsb-vs-hsl-demystified/

System Optimization in Digital Color Imaging

Understanding and exploiting interactions

Raja Bala and Gaurav Sharma

IEEE Signal Processing Magazine · February 2005

Digital image processing

Gonzalez and Woods, 

2nd edition, Prentice Hall, 2002

Which Color Space Should You Use When?

https://havecamerawilltravel.com/photographer/color-profiles/

DIGITAL IMAGING AND PHOTOGRAPHY

On Line Course

University of Delaware

https://www.eecis.udel.edu/~arce/courses/digitalimgproc/

Introduction to Basic Measures of a Digital Image for Pictorial Collections

Kit A. Peterson, Digital Conversion Specialist, June 2005

Prints & Photographs Division, Library of Congress, Washington, D.C. 20540-4730

Color spaces and gamut

Published on April 15, 2015   |  Updated on October 31, 2019

https://www.color-management-guide.com/color-spaces.html

COLOR IN DIGITAL CINEMA

Color Spaces

http://www.updig.org/guidelines/ph_color_spaces.html

https://danpgomez.com/tbl/2016/3/29/whats-the-difference-between-a-color-space-and-a-color-profile

Review and evaluation of color spaces for image/video compression

Samruddhi Y. Kahu1 | Rajesh B. Raut2 | Kishor M. Bhurchandi

Color Res Appl. 2019;44:8–33.

Color filter array

https://en.wikipedia.org/wiki/Color_filter_array#List_of_color_filter_arrays

Eyeing the Camera: into the Next Century

Richard F. Lyon and Paul M. Hubel

Foveon, Inc.
Santa Clara, California, USA

Color Filter Arrays: Design and Performance Analysis

Rastislav Lukac, Member, IEEE, and Konstantinos N. Plataniotis, Senior Member, IEEE

IEEE Transactions on Consumer Electronics, Vol. 51, No. 4, NOVEMBER 2005

Introduction to Bayer Filters

https://www.arrow.com/en/research-and-events/articles/introduction-to-bayer-filters

DIGITAL CAMERA SENSORS

https://www.cambridgeincolour.com/tutorials/camera-sensors.htm

https://www.cambridgeincolour.com

Rethinking Color Cameras

Ayan Chakrabarti

William T. Freeman

Todd Zickler

IEEE 2014

Color Filter Arrays for Quanta Image Sensors 

Omar A. Elgendy, Student Member, IEEE and Stanley H. Chan, Senior Member, IEEE

Quad Bayer sensors: what they are and what they are not

https://www.gsmarena.com/quad_bayer_sensors_explained-news-37459.php

Image sensor format

https://en.wikipedia.org/wiki/Image_sensor_format

Image file formats

https://en.wikipedia.org/wiki/Image_file_formats

Understanding Digital Raw Capture

Adobe

Why Every Editor, Colorist, and VFX Artist Needs to Understand ACES

Ben Bailey 2019

Common RGB Color Spaces

https://nick-shaw.github.io/cinematiccolor/common-rgb-color-spaces.html

On Light, Vision, Appearance, Color and Imaging

On Light, Vision, Appearance, Color and Imaging

This is a topic close to my heart. My masters thesis research was on color prediction and modeling. My research work was published by IPST Atlanta as Technical paper no 469. Those who work in Paper and Printing Industry know IPST very well. It used to be called Institute of Paper Chemistry and was based in Appleton, Wisconsin.

Key Terms

  • Color Science
  • Human Vision
  • Color Models
  • Industrial Color
  • Measurement
  • Color Physics
  • Color Chemistry
  • Color Perception
  • Color Psychology
  • Instruments
  • Light
  • Color Technology
  • Light Absorption
  • Light Scattering
  • Psycho-Physics of Color
  • Reflectance
  • Refraction
  • Gloss
  • Texture
  • Colorimeter
  • Spectrophotometer
  • Color Dyes and Pigments
  • Paint, Plastics, Paper, Textiles
  • Digital Color
  • Device Independent color
  • Computer Monitors
  • Color Theory
  • Color Physics
  • Kubelka Munk Theory
  • Munsell Colors
  • Pantone Colors
  • RIT
  • Newton’s Optics
  • Goethe Color Theory
  • Four Color Problem
  • Primary Colors
  • CIE LAB color
  • CIE LCH color
  • Visual Match
  • Instrument Match
  • Radiative Transfer Theory
  • Two Flux vs Multi Flux Models
  • CIE
  • ICC
  • Optical Society of America
  • Inter-Society Color Council ISCC
  • Color and Appearance
  • Whiteness
  • Yellowness
  • Color Profiles
  • Color Scales
  • CIE XYZ
  • RGB
  • CMYK
  • Rods and Cones

Human Vision

Retina of Human eye has two kind of cells responsible for color vision

Rod Cells. Rod Cells are used for motion and lightness

Cone Cells. Cone Cells are responsible for color vision in the eye retina.

Image Source: Basics of Color Imaging/Yao Wang

Image Source: Basics of Color Imaging/Yao Wang

Image Source: Clarkvision

In the references, I have included many links to articles and papers on the following importatnt topics of color. Many companies who meaure and do testing of color provide excellent tutorials on color. See References.

  • Light and Visible Spectrum
  • What is Color?
  • Color Perception in Human
  • Color Models for Visual Perception
  • Color Physics
  • Dyes and Pigments
  • Color Chemistry
  • Optical Properties of Materials

Color Standards

  • ICC International Color Consortium
  • CIE
  • ISCC Inter Society Color Council

Coloring of Materials

  • Paper
  • Textiles
  • Paints
  • Plastics

Color Meaurement in Industry

  • Colorimeters
  • Spectrophotometers

Color Measurement Companies

  • Xrite
  • Datacolor
  • Konica Minolta
  • Hunterlab
  • Technidyne

Color Prediction and Control

  • Prediction in Lab
  • Online Prediction and Control

Kubelka Munk Theory (KM)

It was developed using Radiative Transfer Theory to measure Light Absorption and Light Scattering by objects. Reflection and Transmission.

Limitations of KM Theory

  • Only Two Flux
  • Errors in measuring Strong Absorption and Weak Scattering
  • Correlation between K and S. As K goes up S goes down
  • Use of Single Constant Vs Two Constant KM Theory
  • Can not measure effects of Fluroscent Dyes FWA OBA

Several efforts have been made since early 1990s, to revise, modify KM theory or develop other multiflux models to improve prediction better than KM model.

Key Recent Researchers

  • Li Yang
  • Per Edstrom
  • L G Coppel
  • Tarja Shakespeare
  • H Granberg

My related posts

Some of my earlier published papers

Sounds True: Speech, Language, and Communication

Myth of Invariance: Sound, Music, and Recurrent Events and Structures

Understanding Rasa: Yoga of Nine Emotions

Key sources of Research

Measurement and Control of the Optical Properties of Paper

Technidyne

https://www.technidyne.com/product-page/measurement-and-control-of-the-optical-properties-of-paper

https://imisrise.tappi.org/TAPPI/Products/20/MCOPP/20MCOPP.aspx

Optical paper properties and their influence on colour reproduction and perceived print quality

Authors:

Ivana Jurič

Igor Karlovits

Ivana Tomić

Dragoljub Novaković

https://www.researchgate.net/publication/275637561_Optical_paper_properties_and_their_influence_on_colour_reproduction_and_perceived_print_quality

An assessment of Saunderson corrections to the diffuse reflectance of paint films

A García-Valenzuela et al 

2011 J. Phys.: Conf. Ser. 274 012125

https://iopscience.iop.org/article/10.1088/1742-6596/274/1/012125/pdf

Review: Optical properties of paper: theory and practice.

R. Farnood.

In Advances in Pulp and Paper Research, Oxford 2009, 

Trans. of the XIVth Fund. Res. Symp. Oxford, 2009,
(S.J. I’Anson, ed.), pp 273–352, FRC, Manchester, 2018

Diffuse Reflectance Spectroscopy; Applications, Standards, and Calibration (With Special Reference to Chromatography)

R. W. Frei

Analytical Research and Development, Pharmaceutical Department Sandoz Ltd., 4002 Basel, Switzerland

(May 26, 1976)

Optical models for colored materials

Mathieu Hébert
Institut d’Optique Graduate School, Saint-Etienne. mathieu.hebert@institutoptique.fr

The Use of Reflectance Measurements in the Determination of Fixation of Reactive Dyes to Cotton

N. Ahmed, D. P. Oulton, J. A. Taylor*

Textile sand Paper Group, School of Materials, University of Manchester, P.O. Box 88, Sackville Street, Manchester M60 1QD, United Kingdom

Received 3 January 2005; accepted 9 August 2005

Two-flux and multiflux matrix models for colored surfaces

Mathieu Hébert

Université de Lyon, Université Jean Monnet de Saint-Etienne, CNRS UMR 5516 Laboratoire Hubert Curien, F-42000, Saint-Etienne, France.

Patrick Emmel
14 rue de Münchendorf, 68220 Folgensbourg, France.

https://hal.archives-ouvertes.fr/hal-01179591/document

DETERMINING SCATTERING AND ABSORPTION COEFFICIENTS BY DIFFUSE ILLUMINATION

USDA 1967

F. A. SIMMONDS and C. L. COENS

Optical Response from Paper

Doctoral Thesis

H Granberg 2003

Sweden

PAPER’S APPEARANCE: A REVIEW

Martin A. Hubbe, Joel J. Pawlak and Alexander A. Koukoulas

2008 BioResources online Journal

Examination of the revised Kubelka–Munk theory: considerations of modeling strategies

Per Edström

Department of Engineering, Physics and Mathematics, Mid Sweden University, SE-87188 Härnösand, Sweden

Received April 5, 2006; revised July 3, 2006; accepted July 18, 2006; posted September 11, 2006 (Doc. ID 70185); published January 10, 2007

Revised KubelkaMunk theory. I. Theory and application

Li Yang and Bjo ̈rn Kruse

Campus Norrko ̈ ping (ITN), Linko ̈ ping University, S-601 74, Norrko ̈ ping, Sweden

Received November 20, 2003; revised manuscript received May 3, 2004; accepted May 5, 2004

Revised Kubelka–Munk theory II Unified framework for homogeneous and inhomogeneous optical media

Article in Journal of the Optical Society of America A · November 2004

Li Yang, Bjo ̈rn Kruse, and Stanley J. Miklavcic

Campus Norrko ̈ ping (ITN), Linko ̈ ping University, S-601 74, Norrko ̈ ping, Sweden

Revised Kubelka–Munk theory. III. A general theory of light propagation in scattering and absorptive media

Li Yang

Graphical Technology/Package Printing Group, Department of Chemical Engineering, Karlstad University, S-651 88 Karlstad, Sweden

Stanley J. Miklavcic

Center for Creative Media Technology, Department of Science and Technology, Linköping University, S-601 74 Norrköping, Sweden

Received January 18, 2005; accepted March 9, 2005

Qualifying the arguments used in the derivation of the revised Kubelka-Munk theory: reply

Yang, Li 

Linköping University, The Institute of Technology. Linköping University, Department of Science and Technology.2007 (English)

In: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION, ISSN 1084-7529, Vol. 24, no 2, p. 557-560

A novel method for studying ink penetration of a print.

Yang L, Fogden A, Pauler N, Sävborg Ö, Kruse B.

Nordic Pulp & Paper Research Journal. 2005;20(4):423-429.

INK-PAPER INTERACTION

A study in ink-jet color reproduction

L i Y a n g 2003

Department of Science and Technology Link ̈oping University

SE-601 74 Norrko ̈ping Sweden

Color Prediction and Separation Models in Printing

-Minimizing the Colorimetric and Spectral Differences employing Multiple Characterization Curves

Yuanyuan Qu

Department of Science and Technology Linköping University, SE-601 74 Norrköping, Sweden Norrköping 2013

Deriving Kubelka–Munk theory from radiative transport 

Christopher Sandoval and Arnold D. Kim*

Applied Mathematics Unit, School of Natural Sciences, University of California, Merced, 5200 North Lake Road, Merced, California 95343, USA
*Corresponding author: adkim@ucmerced.edu

Received November 12, 2013; accepted January 6, 2014;
posted January 16, 2014 (Doc. ID 201164); published February 21, 2014

KUBELKA-MUNK THEORY IN DESCRIBING OPTICAL PROPERTIES OF PAPER (I)

Vesna Džimbeg-Malčić, Željka Barbarić-Mikočević, Katarina Itrić

KUBELKA-MUNK THEORY IN DESCRIBING OPTICAL PROPERTIES OF PAPER (II).

  • Source: Tehnicki vjesnik / Technical Gazette . Jan-Mar2012, Vol. 19 Issue 1, p191-196. 6p. 
  • Author(s): Džimbeg-Malčić, Vesna; Barbarić-Mikočević, Željka; Itrić, Katarina

Applicability conditions of the Kubelka–Munk theory

William E. Vargas and Gunnar A. Niklasson

Extension of the Kubelka–Munk theory of light propagation in intensely scattering materials to fluorescent media 

Leonid Fukshansky and Nina Kazarinova

  • Journal of the Optical Society of America
  • Vol. 70,
  • Issue 9,
  • pp. 1101-1111
  • (1980)

What Has Been Overlooked in Kubelka-Munk Theory?

Author: Yang, Li

Source: NIP & Digital Fabrication Conference, 2005 International Conference on Digital Printing Technologies. Pages 332-679., pp. 376-379(4)

Publisher: Society for Imaging Science and Technology

https://www.ingentaconnect.com/content/ist/nipdf/2005/00002005/00000002/art00012?crawler=true

Kubelka Munk Theory for Efficient Spectral Printer Modeling

Mekides Assefa

https://ntnuopen.ntnu.no/ntnu-xmlui/bitstream/handle/11250/143732/FinalThesisReportMekidesAssefaHIG2.pdf?sequence=1

On Measurements of Effective Residual Ink Concentration (ERIC) of Deinked Papers Using Kubelka-Munk Theory

D.W. Vahey, J.Y. Zhu and C.J. Houtman

Single‐constant simplification of Kubelka‐Munk turbid‐media theory for paint systems—A review

Roy S. Berns Mahnaz Mohammadi

First published: 25 April 2007

Color Research and Application J

https://onlinelibrary.wiley.com/doi/abs/10.1002/col.20309

Spectrophotometric color prediction of mineral pigments with relatively large particle size by single- and two-constant Kubelka-Munk theory

Authors: Li, JunfengWan, Xiaoxia

Source: Color and Imaging Conference, Volume 2017, Number 25, September 2017, pp. 324-329(6)

Publisher: Society for Imaging Science and Technology

https://www.ingentaconnect.com/content/ist/cic/2017/00002017/00000025/art00054

Theory of light propagation incorporating scattering and absorption in turbid media

Li Yang and Stanley J. Miklavcic

Department of Science and Technology, Link ̈oping University, S-601 74, Norrko ̈ping, Sweden

Article in Optics Letters · May 2005

Kubelka-Munk Model for Imperfectly Diffuse Light Distribution in Paper

Li Yang􏰀
Holmen Paper Development Center (HPD), Holmen AB, Sweden E-mail: li.yang@holmenpaper.com

R. D. Hersch

Ecole Polytechnique Fédérale de Lausanne (EPFL), School of Computer and Communication Sciences, Lausanne 1015, Switzerland

Quantification of the Intrinsic Error of the Kubelka–Munk Model Caused by Strong Light Absorption

H. GRANBERG and P. EDSTRÖM

JOURNAL OF PULP AND PAPER SCIENCE: VOL. 29 NO. 11 NOVEMBER 2003

Anisotropic reflectance from turbid media. I. Theory

Neuman, Magnus 

Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.(Pappersoptik och färg)

Edström, Per 

Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.(Pappersoptik och färg)

2010 (English)

In: Journal of the Optical Society of America A, ISSN 0740-3232, Vol. 27, no 5, p. 1032-1039

Mathematical modeling and numerical tools for simulation and design of light scattering in paper and print

Edström, Per 

Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.(FSCN – Fibre Science and Communication Network)ORCID iD: 0000-0002-0529-1009

Mid Sweden University

2007 (English)

Theoretical Investigation of Bioactive Papers Using the Kubelka-Munk Theory

Elina Levi Gendler

Masters of Applied Science Chemical Engineering and Applied Chemistry University of Toronto
2015

The color prediction model of fluorescent prints

Na DongYixin ZhangGuoyun Shi

Proceedings Volume 7241, Color Imaging XIV: Displaying, Processing, Hardcopy, and Applications;72411N (2009) 
Event: IS&T/SPIE Electronic Imaging, 2009, San Jose, California, United States

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/7241/72411N/The-color-prediction-model-of-fluorescent-prints/10.1117/12.808459.short?SSO=1

State of the art on macroscopic models for the determination of thin films optical properties

G. Saridakis, D. Kolokotsa

Technological Educational Institute of Crete, Greece

M. Santamouris

Radiative properties of optically thick fluorescent turbid media

Alexander A. Kokhanovsky

Journal of the Optical Society of America AVol. 26,Issue 8,pp. 1896-1900(2009)

https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-26-8-1896

Radiative properties of optically thick fluorescent turbid media: errata 

A. A. Kokhanovsky  

  • Journal of the Optical Society of America
  • Vol. 27,
  • Issue 9,
  • pp. 2084-2084
  • (2010)

https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-27-9-2084

Spectral Reflectance Model of a Single Sheet of Blank Paper*

Yongchi XU** and Shisheng ZHOU** **

Faculty of Printing and Packaging Engineering, Xi’an University of Technology, Xi’an, 710048 China

https://www.jstage.jst.go.jp/article/nig/51/2/51_103/_pdf

Next Generation Simulation Tools for Optical Properties in Paper and Print

Per Edström
Mid Sweden University, TFM, SE‐87188 Härnösand, Sweden,

Improving the performance of computer color matching procedures 

  • Journal of the Optical Society of America A
  • Vol. 25,
  • Issue 9,
  • pp. 2251-2262
  • (2008)

https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-25-9-2251

A two-phase parameter estimation method for radiative transfer problems in paper industry applications

Per Edstro ̈ m*

Department of Engineering, Physics and Mathematics, Mid Sweden University, Ha ̈rno ̈sand, Sweden

Inverse Problems in Science and Engineering

Vol. 16, No. 7, October 2008, 927–951

A Guide to Understanding Color

Xrite

Understanding CIE *L*a*b Colour Space

Kydex

Understanding Color

Giordino Beretta 2008 and 2010

HP Labs

SPIE

PRECISE COLOR COMMUNICATION  : COLOR CONTROL FROM PERCEPTION TO INSTRUMENTATION

Konica Minolta

The basics of Color Perception and Measurement

HunterLab

The Color Guide and Glossary

Xrite

Color Differences & Tolerances Commercial Color Acceptability

Datacolor

Defining and Communicating Color: The CIELAB System

SAPPI

Color Science Course

Berns

RIT

ftp://ftp.cis.rit.edu/mcsl/berns/Berns_color_course.pdf

Using Color Effectively in Computer Graphics

Lindsay W. MacDonald

University of Derby, UK

Color Management Fundamentals

Color realism and color science

Alex Byrne

Department of Linguistics and Philosophy, Massachusetts Institute of Technology, Cambridge, MA 02139
abyrne@mit.edu mit.edu/abyrne/www

David R. Hilbert

Department of Philosophy and Laboratory of Integrative Neuroscience, University of Illinois at Chicago, Chicago, IL 60607
hilbert@uic.edu http://www.uic.edu/~hilbert/

BEHAVIORAL AND BRAIN SCIENCES (2003) 26, 3–64 

Introduction to Color Models

Routledge

Color Appearance Models

Second Edition

Mark D. Fairchild

Munsell Color Science Laboratory Rochester Institute of Technology, USA

COLOR IN GEMS: THE NEW TECHNOLOGIES

By George R. Rossman

THE NATURE OF LIGHT AND COLOR

Kodak

Light and Color

Colour physics and colour measurement: state-of-the-art and challenges

S Westland

THE PHYSICS OF COLOUR

Mil􏰀osz Michalski

Institute of Physics Nicolaus Copernicus University

July 3, 2012

Lecture 26: Color and Light

On the Kubelka-Munk Single-Constant/Two-Constant Theories

Ning Pan and others

https://www.researchgate.net/publication/216567998_On_the_Kubelka-Munk_Single-ConstantTwo-Constant_Theories

Kubelka-Munk Prediction for Dark Mixtures

  • December 2013
  • Conference: 5th International Color and Coatings Congress (ICCC 2013)
  • At: Isfahan, Iran

Authors:

Farhad Moghareh Abed

Roy S. Berns

https://www.researchgate.net/publication/323656636_Kubelka-Munk_Prediction_for_Dark_Mixtures

Colour Measurement and Analysis in Fresh and Processed Foods: A Review

Pankaj B Pathare

Umezuruike Linus Opara

Fahad Al-Julanda Al-Said

https://www.researchgate.net/publication/225037588_Colour_Measurement_and_Analysis_in_Fresh_and_Processed_Foods_A_Review

Extending Kubelka-Munk’s Theory with Lateral Light Scattering

Safer Mourad *, Patrick Emmel **, Klaus Simon and Roger David Hersch **

IS&T’s NIP17: International Conference on Digital Printing Technologies

Kubelka Munk Model in Paper Optics: Successes, Limitations and Improvements

L. Yang

Page 81

DETERMINATION OF OPTICAL CHARACTERISTICS OF MATERIALS FOR COMPUTER COLORANT ANALYSIS

Gülen Bayhan

https://www.academia.edu/5407157/DETERMINATION_OF_OPTICAL_CHARACTERISTICS_OF_MATERIALS_FOR_COMPUTER_COLORANT_ANALYSIS

DETERMINATION OF OPTICAL CHARACTERISTICS OF MATERIALS FOR COMPUTER COLORANT ANALYSIS

Dibakar Raj Pant.

University of Joensuu Department of Computer Science Pro gradu
April, 2006

ftp://www.cs.joensuu.fi/pub/Theses/2005_MSc_Pant_Dibakar_Raj.pdf

Next Generation Simulation Tools for Optical Properties in Paper and Print

Per Edström
Mid Sweden University, TFM, SE‐87188 Härnösand, Sweden, per.edstrom@miun.se

The optical properties of bleached kraft pulp

Steven R. Middleton and Anthony M. Scallan, 

Pulp and Paper Research Institute of Canada, Pointe Claire, Canada

Light Scattering in Fibrous Sheets

Edwin W Arnold

IPC PhD Thesis 1962

https://smartech.gatech.edu/bitstream/handle/1853/5809/arnold_ew.pdf?…

INFLUENCE OF LIGHT AND TEMPERATURE ON OPTICAL PROPERTIES OF PAPERS

BARBARA BLAZNIK, DIANA GREGOR-SVETEC and SABINA BRAČKO

Department of Information and Graphic Arts Technology, Faculty of Natural Sciences and Engineering, University of Ljubljana, Snežniška 5, SI-1000 Ljubljana, Slovenia

Determining optical properties of mechanical pulps 

Anette Karlsson, Sofia Enberg, Mats Rundlöf, Magnus Paulsson and Per Edström

Nordic Pulp and Paper Research Journal Vol 27 no.3/2012

Color iQC and Color iMatch Multi Flux Matching Guide

Version 8.0 | July 2012

Xrite

Industrial Color Physics 

By Georg A. Klein

PREDICTION OF PAPER COLOR:
A PROCESS SIMULATION APPROACH

G.L. JONES, M. CHATURVEDI, AND R. ARAVAMUTHAN

MARCH 1993

IPST Technical Paper Series 469

Click to access tps-469.pdf

Application of Kubelka-Munk Theory in Device-independent Color Space Error Diffusion

Shilin Guo and Guo Li

Hewlett-Packard Company, San Diego Site

The Practical Guide To Color Theory For Photographers

In-Depth Guide on How to Measure Color in Plastics

https://www.ptonline.com/articles/in-depth-guide-on-how-to-measure-color-in-plastics

A Guide to Understanding Color Communication

Tintometer Group

A partial explanation of the dependence between light scattering and light absorption in the Kubelka-Munk model 

M. Neuman, L. G. Coppel and P. Edström

Nordic Pulp and Paper Research Journal Vol 27 no.2/2012

Limitations of the efficiency of fluorescent whitening agents in uncoated paper

Gustafsson Coppel, Ludovic 

Andersson, Mattias 

Edström, Per 

Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.

Kinnunen, Jussi 

Univ Eastern Finland, Dept Math & Phys, FI-80101 Joensuu, Finland.

2011 (English) In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 26, no 3, p. 319-328

Determination of light scattering coefficient of dark and heavy sheets

KNOX, J.M., and WAHREN, D.

Tappi J 1984

Whiteness and Fluorescence in Layered Paper and Boards

Perception and Optical Modelling

L G Coppel

PhD Thesis

Mid Sweden University

Extension of the Stokes equation for layered constructions to fluorescent turbid media

Ludovic G. Coppel,1,2 Magnus Neuman,2 and Per Edström2,*
1Innventia AB, Box 5604, SE-11486 Stockholm, Sweden
2Department of Natural Sciences, Engineering and Mathematics, Mid Sweden University, SE-87188 Härnösand, Sweden 

*Corresponding author: per.edstrom@miun.se

Received January 3, 2012; accepted January 20, 2012;
posted January 24, 2012 (Doc. ID 160521); published March 22, 2012

Determination of quantum efficiency in fluorescing turbid media.

Coppel LG,  Andersson M,  Edström P

Applied Optics, 31 May 2011, 50(17):2784-2792

Extension of the Kubelka–Munk theory of light propagation in intensely scattering materials to fluorescent media 

Leonid Fukshansky and Nina Kazarinova

  • Journal of the Optical Society of America
  • Vol. 70,
  • Issue 9,
  • pp. 1101-1111
  • (1980)

https://www.osapublishing.org/josa/abstract.cfm?uri=josa-70-9-1101

Revised Optical Properties of Turbid Media on a Base of Generally Improved Two-Flux Kubelka-Munk Approach

D. A. Rogatkin1, and V. V. Tchernyi2

Understanding Color Communication

Xrite

Correspondences between the Kubelka-Munk and the Stokes model of strongly light-scattering materials. II: Implications

OLF, H. G
[1] North Carolina state univ., dep. wood & paper sci., Raleigh NC 27695-8005, United StatesSource

Tappi journal1989, Vol 72, Num 7, pp 159-163

Precise Color Communication

Konica Minolta

The Color Guide and Glossary

Xrite

CIE LAB Color

Sappi

Principles of Color Technology for Color Imaging Scientists and Engineers

Berns

RIT

ftp://ftp.cis.rit.edu/mcsl/berns/Berns_color_course.pdf

Using Color Effectively in Computer Graphics

Lindsay W. MacDonald

University of Derby, UK

Color Management Fundamentals Wide Format Series

Introduction to Color Models

Anisotropic reflectance from turbid media. I. Theory

Neuman, Magnus 

Edström, Per 

Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.(Pappersoptik och färg)

2010 (English)In: Journal of the Optical Society of America A, ISSN 0740-3232, Vol. 27, no 5, p. 1032-1039

Anisotropic reflectance from turbid media. II. Measurements 

Magnus Neuman and Per Edström

  • Journal of the Optical Society of America A
  • Vol. 27,
  • Issue 5,
  • pp. 1040-1045
  • (2010)

https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-27-5-1040

Angular dependence of fluorescence from turbid media

Ludovic G. Coppel,1,∗ Niklas Johansson,and Magnus Neuman2

https://www.researchgate.net/publication/281069011_Angular_dependence_of_fluorescence_from_turbid_media

Limitations in the efficiency of fluorescent whitening agents in uncoated paper

Ludovic G. Coppel, Mattias Andersson, Per Edström and Jussi Kinnunen

Fluorescence model for multi-layer papers using conventional spectrophotometers

 L. G. Coppel, M. Andersson, M. Neuman and P. Edström

Nordic Pulp & Paper Research Journal | Volume 27: Issue 2

Whiteness Assessment: A Primer Concepts, Determination and Control of Perceived Whiteness

September 2006

Claudio Puebla

https://www.researchgate.net/publication/331802584_Whiteness_Assessment_A_Primer_Concepts_Determination_and_Control_of_Perceived_Whiteness

FLUORESCENCE AND THE PAPER APPEARANCE – CHALLENGES IN PAPER COLORING

Dr. Tarja Shakespeare1, Dr. John Shakespeare2

2009

MODELING A COLORING PROCESS 

Tarja Shakespeare, John Shakespeare 

US Patent

A fluorescent extension to the Kubelka–Munk model

Tarja Shakespeare

John Shakespeare

https://www.researchgate.net/publication/229559432_A_fluorescent_extension_to_the_Kubelka-Munk_model

Radiative properties of optically thick fluorescent turbid media

Alexander A Kokhanovsky 1

https://www.osapublishing.org/josaa/abstract.cfm?uri=josaa-26-8-1896

A New Look at Fundamentals of the Photometric Light Transport and Scattering Theory. Part 2: One-Dimensional Scattering with Absorption

Authors: Persheyev S.Rogatkin D.A.Published: 22.11.2017 
Published in issue: #6(75)/2017 
DOI: 10.18698/1812-3368-2017-6-65-78

http://vestniken.ru/eng/catalog/phys/opt/787.html

Spectral prediction model for color prints on paper with fluorescent additives.

Hersch RD1

Applied Optics, 30 Nov 2008, 47(36):6710-6722

https://europepmc.org/article/med/19104523

Relationship between the Kubelka-Munk scattering and radiative transfer coefficients

Suresh N Thennadil 1

https://pubmed.ncbi.nlm.nih.gov/18594602/

Effect of strong absorption on the Kubelka-Munk scattering coefficient

A. KoukoulasB. Jordan

Published 1997

https://www.semanticscholar.org/paper/Effect-of-strong-absorption-on-the-Kubelka-Munk-Koukoulas-Jordan/fee09ae8d3bfd2e8d58eff34321f60eec89d445b

A note concerning the interaction between light scattering and light absorption in the application of the Kubelka-Munk equations

Mats RundlöfJ. A. Bristow

Published 1997

https://www.semanticscholar.org/paper/A-note-concerning-the-interaction-between-light-and-Rundlöf-Bristow/c87c601ad12a90ba9e241469dd45f85797c19f70

Color Measurements on Prints Containing Fluorescent Whitening Agents

Mattias Andersson and Ole Norberg

Digital Printing Center, Mid Sweden University, 89118 Örnsköldsvik, Sweden

https://www.researchgate.net/publication/238022968_Color_measurements_on_prints_containing_fluorescent_whitening_agents_-_art_no_64930Q

Colorant modelling for on-line paper coloring: evaluations of models and an extension to Kubelka-Munk model

Shakespeare, T. (2000)

Tampere University of Technology

https://www.researchgate.net/publication/328873794_Colorant_Modelling_for_On-Line_Paper_Coloring_Evaluations_of_Models_and_an_Extentsion_to_Kubelka-Munk_Model

Fluorescent White Dyes: Calculation of Fluorescence from Reflectivity Values 

Eugene Allen

1964 OSAJ

https://www.osapublishing.org/josa/abstract.cfm?uri=josa-54-4-506

Extension of the Kubelka–Munk theory for fluorescent turbid media to a nonopaque layer on a background

Article in Journal of the Optical Society of America A · July 2011

https://www.researchgate.net/publication/51472634_Extension_of_the_Kubelka-Munk_theory_for_fluorescent_turbid_media_to_a_nonopaque_layer_on_a_background

Tutorial on Fluorescence and Fluorescent Instrumentation

Colour measurement in practice 

Contemporary wool dyeing and finishing

Dr Rex Brady Deakin University

Separation of the Spectral Radiance Factor Curve of Fluorescent Substances into Reflected and Fluoresced Components 

Eugene Allen

  • Applied Optics
  • Vol. 12,
  • Issue 2,
  • pp. 289-293
  • (1973)

https://www.osapublishing.org/ao/abstract.cfm?uri=ao-12-2-289

Fluorescence and kubelka‐munk theory

James S. Bonham

First published: Autumn (Fall) 1986

Color Research and Application J

https://onlinelibrary.wiley.com/doi/abs/10.1002/col.5080110310

Spectrophotometry of fluorescent pigments

R Donaldson1

1954


British Journal of Applied PhysicsVolume 5Number 6

https://iopscience.iop.org/article/10.1088/0508-3443/5/6/303

KUBELKA-MUNK THEORY OF FLUORESCENT COLORANTS

He Guoxin (Department of Textile Technology)

1988

http://en.cnki.com.cn/Article_en/CJFDTotal-DHDZ198804018.htm

Problems in colour measurement of fluorescent paper grades

Tarja Shakespeare John Shakespeare11

Analytica Chimica Acta

Volume 380, Issues 2–3, 2 February 1999, Pages 227-242

https://www.sciencedirect.com/science/article/abs/pii/S0003267098004838

Spectral Colour Prediction Model for a Transparent Fluorescent Ink on Paper*

Patrick Emmel, Roger David Hersch

Laboratoire de Systèmes Périphériques

Ecole Polytechnique Fédérale de Lausanne (EPFL),

The extended Kubelka–Munk theory and its application to spectroscopy

2020

https://link.springer.com/article/10.1007/s40828-019-0097-0

The color prediction model of fluorescent prints

Na DongYixin ZhangGuoyun Shi

Author Affiliations +Proceedings Volume 7241, Color Imaging XIV: Displaying, Processing, Hardcopy, and Applications;72411N (2009) 
Event: IS&T/SPIE Electronic Imaging, 2009, San Jose, California, United States

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/7241/72411N/The-color-prediction-model-of-fluorescent-prints/10.1117/12.808459.short?SSO=1

REVIEW: USE OF OPTICAL BRIGHTENING AGENTS (OBAs) IN THE PRODUCTION OF PAPER CONTAINING HIGH-YIELD PULPS

He Shi,a Hongbin Liu,a,b,* Yonghao Ni,a,c Zhirun Yuan,d Xuejun Zou,d and Yajun Zhou

The Kubelka-Munk Theory for Color Image Invariant Properties

Jan-Mark Geusebroek, Theo Gevers, Arnold W.M. Smeulders Intelligent Sensory Information Systems, University of Amsterdam

Kruislaan 403, 1098 SJ Amsterdam, The Netherlands

Determination of quantum efficiency in fluorescing turbid media 

Ludovic Gustafsson Coppel, Mattias Andersson, and Per Edström

Applied OpticsVol. 50,Issue 17,pp. 2784-2792(2011)

https://www.osapublishing.org/ao/abstract.cfm?uri=ao-50-17-2784

4.2 Colour Science

ALAN MARTIN

Quantification of the Intrinsic Error of the Kubelka–Munk Model Caused by Strong Light Absorption

H. GRANBERG and P. EDSTRÖM

Effect of Moisture on Paper Color

SHAKESPEARE TARJA and SHAKESPEARE JOHN

page 85

Basic equations used in computer color matching, II. Tristimulus match, two-constant theory 

Eugene Allen

Journal of the Optical Society of AmericaVol. 64,Issue 7,pp. 991-993(1974)

Spectrophotometric color formulation based on two-constant Kubelka-Munk theory

Eric Walowit

(1985). Thesis. Rochester Institute of Technology

Basic Equations Used in Computer Color Matching 

Eugene Allen

Journal of the Optical Society of AmericaVol. 56,Issue 9,pp. 1256-1259(1966)

https://www.osapublishing.org/josa/abstract.cfm?uri=josa-56-9-1256

Computer-Aided Color Formulation (How to Formulate Color)

Posted March 02, 2017 by Mike Huda

Xrite

https://www.xrite.com/blog/computer-aided-color-formulation

COMIC: An Analog Computer in the Colorant Industry

July-Sept. 2014, pp. 4-18, vol. 36

Computer

https://www.computer.org/csdl/magazine/an/2014/03/man2014030004/13rRUx0Pqrq

An investigation of the optical scattering and absorption coefficients of dyed handsheets and the application of the ICI system of color specification to these handsheets

Foote, William J. (William John)

1938 PhD Thesis IPC

https://smartech.gatech.edu/handle/1853/5491

NUMERICAL ANALYSIS OF THE INFLUENCE OF FORMATION ON THE OPTICAL PROPERTIES OF PAPER

DOUGLAS WAHREN

FEBRUARY, 1987 IPC Technical Paper 223

Mathematical Modelling of
Light Scattering in Paper and Print

Per Edström

PhD Thesis Mid Sweden University Sweden 2004

A Comparison Between the Coefficients of the Kubelka-Munk and DORT2002 Models

Per Edström
Mid Sweden University 2003

Simulation and modeling of light scattering in paper and print applications

Edström P. (2010)

In: Kokhanovsky A. (eds) Light Scattering Reviews 5. Springer Praxis Books. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-10336-0_10

https://link.springer.com/chapter/10.1007/978-3-642-10336-0_10

Measuring and Modelling Light Scattering in Paper

Niklas Johansson

Department of Natural Sciences Mid Sweden University

Doctoral Thesis No. 224 O ̈ rnsko ̈ ldsvik, Sweden 2015

Does the photon-diffusion coefficient depend on absorption?

T. Durduran and A. G. Yodh

B. Chance

D. A. Boas

J. Opt. Soc. Am. A/Vol. 14, No. 12/December 1997

Some of my earlier published papers

Some of my earlier published papers

Below is a list of my papers which have been published in referred journals or as technical paper.  All of the work was done by me during my post graduate studies at Western Michigan University, Kalamazoo, Michigan, USA.  I was there since 1987 to 1991.

My research projects included:

  • Paper Recycling
  • Paper Color modeling and prediction
  • Simulation Modeling and Analysis of a Just In Time production system

Based on my research, I was awarded All University Graduate Creative and Research Scholar award by the University and was given a Award Citation by the University President in a Award Ceremony.

 

Effect of Recycling on the Physical Properties of Specific Fibers and Their Networks,”

by John F. Bobalek and Mayank Chaturvedi. In Proceedings, 1988 TAPPI Pulping Conference, p. 183-187.

 

 

Bobalek, John F., and Mayank Chaturvedi. 1989.

“The Effects of Recycling on the Physical Properties of Handsheets with Respect to Specific Wood Species.”

Tappi Journal June: 123- 125.

 

http://imisrise.tappi.org/TAPPI/Products/89/JUN/89JUN123.aspx

 

 

PREDICTION OF PAPER COLOR: A PROCESS SIMULATION APPROACH

WMU Masters Thesis 890

http://scholarworks.wmich.edu/masters_theses/890/

 

 

PREDICTION OF PAPER COLOR: A PROCESS SIMULATION APPROACH

IPST Technical Paper 469

Click to access tps-469.pdf

 

 

PREDICTION OF PAPER COLOR: A PROCESS SIMULATION APPROACH

IPST Annual Research Review

 

Click to access a31667.pdf

 

 

Simulation modelling and analysis of a JIT production system

Mayank Chaturvedi, Damodar Y Golhar
1992/1/1
Production Planning & Control
Volume 3 Issue 1 Pages 81-92
Taylor & Francis Group

My Research Page at Bepress.com