Color (American English) or colour (Commonwealth English) is the
characteristic of human visual perception described through color
categories, with names such as red, orange, yellow, green, blue, or
purple. This perception of color derives from the stimulation of cone
cells in the human eye by electromagnetic radiation in the visible
Color categories and physical specifications of color are
associated with objects through the wavelength of the light that is
reflected from them. This reflection is governed by the object's
physical properties such as light absorption, emission spectra, etc.
By defining a color space, colors can be identified numerically by
RGB color space
RGB color space for instance is a color space
corresponding to human trichromacy and to the three cone cell types
that respond to three bands of light: long wavelengths, peaking near
564–580 nm (red); medium-wavelength, peaking near 534–545 nm
(green); and short-wavelength light, near 420–440 nm
(blue). There may also be more than three color dimensions in
other color spaces, such as in the CMYK color model, wherein one of
the dimensions relates to a color's colorfulness).
The photo-receptivity of the "eyes" of other species also varies
considerably from that of humans and so results in correspondingly
different color perceptions that cannot readily be compared to one
another. Honeybees and bumblebees for instance have trichromatic color
vision sensitive to ultraviolet but is insensitive to red. Papilio
butterflies possess six types of photoreceptors and may have
pentachromatic vision. The most complex color vision system in the
animal kingdom has been found in stomatopods (such as the mantis
shrimp) with up to 12 spectral receptor types thought to work as
multiple dichromatic units.
The science of color is sometimes called chromatics, colorimetry, or
simply color science. It includes the study of the perception of color
by the human eye and brain, the origin of color in materials, color
theory in art, and the physics of electromagnetic radiation in the
visible range (that is, what is commonly referred to simply as light).
Physics of color
1.1 Spectral colors
Color of objects
2.1 Development of theories of color vision
Color in the eye
Color in the brain
2.4 Nonstandard color perception
3 Spectral colors and color reproduction
3.1 Additive coloring
3.2 Subtractive coloring
3.3 Structural color
4 Additional terms
5 See also
7 External links and sources
Physics of color
Continuous optical spectrum rendered into the sRGB color space.
The colors of the visible light spectrum
~ 700–635 nm
~ 430–480 THz
~ 635–590 nm
~ 480–510 THz
~ 590–560 nm
~ 510–540 THz
~ 560–520 nm
~ 540–580 THz
~ 520–490 nm
~ 580–610 THz
~ 490–450 nm
~ 610–670 THz
Violet or Purple
~ 450–400 nm
~ 670–750 THz
Color, wavelength, frequency and energy of light
displaystyle lambda ,!
displaystyle nu ,!
displaystyle nu _ b ,!
Violet or Purple
Electromagnetic radiation is characterized by its wavelength (or
frequency) and its intensity. When the wavelength is within the
visible spectrum (the range of wavelengths humans can perceive,
approximately from 390 nm to 700 nm), it is known as
Most light sources emit light at many different wavelengths; a
source's spectrum is a distribution giving its intensity at each
wavelength. Although the spectrum of light arriving at the eye from a
given direction determines the color sensation in that direction,
there are many more possible spectral combinations than color
sensations. In fact, one may formally define a color as a class of
spectra that give rise to the same color sensation, although such
classes would vary widely among different species, and to a lesser
extent among individuals within the same species. In each such class
the members are called metamers of the color in question.
The familiar colors of the rainbow in the spectrum—named using the
Latin word for appearance or apparition by
Isaac Newton in
1671—include all those colors that can be produced by visible light
of a single wavelength only, the pure spectral or monochromatic
colors. The table at right shows approximate frequencies (in
terahertz) and wavelengths (in nanometers) for various pure spectral
colors. The wavelengths listed are as measured in air or vacuum (see
The color table should not be interpreted as a definitive list—the
pure spectral colors form a continuous spectrum, and how it is divided
into distinct colors linguistically is a matter of culture and
historical contingency (although people everywhere have been shown to
perceive colors in the same way). A common list identifies six main
bands: red, orange, yellow, green, blue, and violet. Newton's
conception included a seventh color, indigo, between blue and violet.
It is possible that what Newton referred to as blue is nearer to what
today is known as cyan, and that indigo was simply the dark blue of
the indigo dye that was being imported at the time.
The intensity of a spectral color, relative to the context in which it
is viewed, may alter its perception considerably; for example, a
low-intensity orange-yellow is brown, and a low-intensity yellow-green
Color of objects
The color of an object depends on both the physics of the object in
its environment and the characteristics of the perceiving eye and
brain. Physically, objects can be said to have the color of the light
leaving their surfaces, which normally depends on the spectrum of the
incident illumination and the reflectance properties of the surface,
as well as potentially on the angles of illumination and viewing. Some
objects not only reflect light, but also transmit light or emit light
themselves, which also contributes to the color. A viewer's perception
of the object's color depends not only on the spectrum of the light
leaving its surface, but also on a host of contextual cues, so that
color differences between objects can be discerned mostly independent
of the lighting spectrum, viewing angle, etc. This effect is known as
The upper disk and the lower disk have exactly the same objective
color, and are in identical gray surroundings; based on context
differences, humans perceive the squares as having different
reflectances, and may interpret the colors as different color
categories; see checker shadow illusion.
Some generalizations of the physics can be drawn, neglecting
perceptual effects for now:
Light arriving at an opaque surface is either reflected "specularly"
(that is, in the manner of a mirror), scattered (that is, reflected
with diffuse scattering), or absorbed – or some combination of
Opaque objects that do not reflect specularly (which tend to have
rough surfaces) have their color determined by which wavelengths of
light they scatter strongly (with the light that is not scattered
being absorbed). If objects scatter all wavelengths with roughly equal
strength, they appear white. If they absorb all wavelengths, they
Opaque objects that specularly reflect light of different wavelengths
with different efficiencies look like mirrors tinted with colors
determined by those differences. An object that reflects some fraction
of impinging light and absorbs the rest may look black but also be
faintly reflective; examples are black objects coated with layers of
enamel or lacquer.
Objects that transmit light are either translucent (scattering the
transmitted light) or transparent (not scattering the transmitted
light). If they also absorb (or reflect) light of various wavelengths
differentially, they appear tinted with a color determined by the
nature of that absorption (or that reflectance).
Objects may emit light that they generate from having excited
electrons, rather than merely reflecting or transmitting light. The
electrons may be excited due to elevated temperature (incandescence),
as a result of chemical reactions (chemoluminescence), after absorbing
light of other frequencies ("fluorescence" or "phosphorescence") or
from electrical contacts as in light emitting diodes, or other light
To summarize, the color of an object is a complex result of its
surface properties, its transmission properties, and its emission
properties, all of which contribute to the mix of wavelengths in the
light leaving the surface of the object. The perceived color is then
further conditioned by the nature of the ambient illumination, and by
the color properties of other objects nearby, and via other
characteristics of the perceiving eye and brain.
When viewed in full size, this image contains about 16 million pixels,
each corresponding to a different color on the full set of RGB colors.
The human eye can distinguish about 10 million different colors.
Development of theories of color vision
Aristotle and other ancient scientists had already written on
the nature of light and color vision, it was not until Newton that
light was identified as the source of the color sensation. In 1810,
Goethe published his comprehensive Theory of Colors in which he
ascribed physiological effects to color that are now understood as
In 1801 Thomas Young proposed his trichromatic theory, based on the
observation that any color could be matched with a combination of
three lights. This theory was later refined by
James Clerk Maxwell
James Clerk Maxwell and
Hermann von Helmholtz. As Helmholtz puts it, "the principles of
Newton's law of mixture were experimentally confirmed by Maxwell in
1856. Young's theory of color sensations, like so much else that this
marvelous investigator achieved in advance of his time, remained
unnoticed until Maxwell directed attention to it."
At the same time as Helmholtz,
Ewald Hering developed the opponent
process theory of color, noting that color blindness and afterimages
typically come in opponent pairs (red-green, blue-orange,
yellow-violet, and black-white). Ultimately these two theories were
synthesized in 1957 by Hurvich and Jameson, who showed that retinal
processing corresponds to the trichromatic theory, while processing at
the level of the lateral geniculate nucleus corresponds to the
In 1931, an international group of experts known as the Commission
internationale de l'éclairage (CIE) developed a mathematical color
model, which mapped out the space of observable colors and assigned a
set of three numbers to each.
Color in the eye
Normalized typical human cone cell responses (S, M, and L types) to
monochromatic spectral stimuli
The ability of the human eye to distinguish colors is based upon the
varying sensitivity of different cells in the retina to light of
Humans are trichromatic—the retina contains
three types of color receptor cells, or cones. One type, relatively
distinct from the other two, is most responsive to light that is
perceived as blue or blue-violet, with wavelengths around 450 nm;
cones of this type are sometimes called short-wavelength cones, S
cones, or blue cones. The other two types are closely related
genetically and chemically: middle-wavelength cones, M cones, or green
cones are most sensitive to light perceived as green, with wavelengths
around 540 nm, while the long-wavelength cones, L cones, or red
cones, are most sensitive to light is perceived as greenish yellow,
with wavelengths around 570 nm.
Light, no matter how complex its composition of wavelengths, is
reduced to three color components by the eye. Each cone type adheres
to the principle of univariance, which is that each cone's output is
determined by the amount of light that falls on it over all
wavelengths. For each location in the visual field, the three types of
cones yield three signals based on the extent to which each is
stimulated. These amounts of stimulation are sometimes called
The response curve as a function of wavelength varies for each type of
cone. Because the curves overlap, some tristimulus values do not occur
for any incoming light combination. For example, it is not possible to
stimulate only the mid-wavelength (so-called "green") cones; the other
cones will inevitably be stimulated to some degree at the same time.
The set of all possible tristimulus values determines the human color
space. It has been estimated that humans can distinguish roughly 10
million different colors.
The other type of light-sensitive cell in the eye, the rod, has a
different response curve. In normal situations, when light is bright
enough to strongly stimulate the cones, rods play virtually no role in
vision at all. On the other hand, in dim light, the cones are
understimulated leaving only the signal from the rods, resulting in a
colorless response. (Furthermore, the rods are barely sensitive to
light in the "red" range.) In certain conditions of intermediate
illumination, the rod response and a weak cone response can together
result in color discriminations not accounted for by cone responses
alone. These effects, combined, are summarized also in the Kruithof
curve, that describes the change of color perception and pleasingness
of light as function of temperature and intensity.
Color in the brain
The visual dorsal stream (green) and ventral stream (purple) are
shown. The ventral stream is responsible for color perception.
While the mechanisms of color vision at the level of the retina are
well-described in terms of tristimulus values, color processing after
that point is organized differently. A dominant theory of color vision
proposes that color information is transmitted out of the eye by three
opponent processes, or opponent channels, each constructed from the
raw output of the cones: a red–green channel, a blue–yellow
channel, and a black–white "luminance" channel. This theory has been
supported by neurobiology, and accounts for the structure of our
subjective color experience. Specifically, it explains why humans
cannot perceive a "reddish green" or "yellowish blue", and it predicts
the color wheel: it is the collection of colors for which at least one
of the two color channels measures a value at one of its extremes.
The exact nature of color perception beyond the processing already
described, and indeed the status of color as a feature of the
perceived world or rather as a feature of our perception of the world
– a type of qualia – is a matter of complex and continuing
Nonstandard color perception
If one or more types of a person's color-sensing cones are missing or
less responsive than normal to incoming light, that person can
distinguish fewer colors and is said to be color deficient or color
blind (though this latter term can be misleading; almost all color
deficient individuals can distinguish at least some colors). Some
kinds of color deficiency are caused by anomalies in the number or
nature of cones in the retina. Others (like central or cortical
achromatopsia) are caused by neural anomalies in those parts of the
brain where visual processing takes place.
Main article: Tetrachromacy
While most humans are trichromatic (having three types of color
receptors), many animals, known as tetrachromats, have four types.
These include some species of spiders, most marsupials, birds,
reptiles, and many species of fish. Other species are sensitive to
only two axes of color or do not perceive color at all; these are
called dichromats and monochromats respectively. A distinction is made
between retinal tetrachromacy (having four pigments in cone cells in
the retina, compared to three in trichromats) and functional
tetrachromacy (having the ability to make enhanced color
discriminations based on that retinal difference). As many as half of
all women are retinal tetrachromats.:p.256 The phenomenon arises
when an individual receives two slightly different copies of the gene
for either the medium- or long-wavelength cones, which are carried on
the X chromosome. To have two different genes, a person must have
two X chromosomes, which is why the phenomenon only occurs in
women. There is one scholarly report that confirms the existence
of a functional tetrachromat.
In certain forms of synesthesia/ideasthesia, perceiving letters and
numbers (grapheme–color synesthesia) or hearing musical sounds
(music–color synesthesia) will lead to the unusual additional
experiences of seeing colors. Behavioral and functional neuroimaging
experiments have demonstrated that these color experiences lead to
changes in behavioral tasks and lead to increased activation of brain
regions involved in color perception, thus demonstrating their
reality, and similarity to real color percepts, albeit evoked through
a non-standard route.
After exposure to strong light in their sensitivity range,
photoreceptors of a given type become desensitized. For a few seconds
after the light ceases, they will continue to signal less strongly
than they otherwise would. Colors observed during that period will
appear to lack the color component detected by the desensitized
photoreceptors. This effect is responsible for the phenomenon of
afterimages, in which the eye may continue to see a bright figure
after looking away from it, but in a complementary color.
Afterimage effects have also been utilized by artists, including
Vincent van Gogh.
When an artist uses a limited color palette, the eye tends to
compensate by seeing any gray or neutral color as the color which is
missing from the color wheel. For example, in a limited palette
consisting of red, yellow, black, and white, a mixture of yellow and
black will appear as a variety of green, a mixture of red and black
will appear as a variety of purple, and pure gray will appear
The trichromatic theory is strictly true when the visual system is in
a fixed state of adaptation. In reality, the visual system is
constantly adapting to changes in the environment and compares the
various colors in a scene to reduce the effects of the illumination.
If a scene is illuminated with one light, and then with another, as
long as the difference between the light sources stays within a
reasonable range, the colors in the scene appear relatively constant
to us. This was studied by
Edwin Land in the 1970s and led to his
retinex theory of color constancy.
Both phenomena are readily explained and mathematically modeled with
modern theories of chromatic adaptation and color appearance (e.g.
CIECAM02, iCAM). There is no need to dismiss the trichromatic
theory of vision, but rather it can be enhanced with an understanding
of how the visual system adapts to changes in the viewing environment.
Lists of colors
Lists of colors and Web colors
Colors vary in several different ways, including hue (shades of red,
orange, yellow, green, blue, and violet), saturation, brightness, and
gloss. Some color words are derived from the name of an object of that
color, such as "orange" or "salmon", while others are abstract, like
In the 1969 study Basic
Color Terms: Their Universality and Evolution,
Brent Berlin and
Paul Kay describe a pattern in naming "basic" colors
(like "red" but not "red-orange" or "dark red" or "blood red", which
are "shades" of red). All languages that have two "basic" color names
distinguish dark/cool colors from bright/warm colors. The next colors
to be distinguished are usually red and then yellow or green. All
languages with six "basic" colors include black, white, red, green,
blue, and yellow. The pattern holds up to a set of twelve: black,
gray, white, pink, red, orange, yellow, green, blue, purple, brown,
and azure (distinct from blue in Russian and Italian, but not
Individual colors have a variety of cultural associations such as
national colors (in general described in individual color articles and
color symbolism). The field of color psychology attempts to identify
the effects of color on human emotion and activity.
Chromotherapy is a
form of alternative medicine attributed to various Eastern traditions.
Colors have different associations in different countries and
Different colors have been demonstrated to have effects on cognition.
For example, researchers at the University of Linz in Austria
demonstrated that the color red significantly decreases cognitive
functioning in men.
Spectral colors and color reproduction
CIE 1931 color space
CIE 1931 color space chromaticity diagram. The outer curved
boundary is the spectral (or monochromatic) locus, with wavelengths
shown in nanometers. The colors depicted depend on the color space of
the device on which you are viewing the image, and therefore may not
be a strictly accurate representation of the color at a particular
position, and especially not for monochromatic colors.
Most light sources are mixtures of various wavelengths of light. Many
such sources can still effectively produce a spectral color, as the
eye cannot distinguish them from single-wavelength sources. For
example, most computer displays reproduce the spectral color orange as
a combination of red and green light; it appears orange because the
red and green are mixed in the right proportions to allow the eye's
cones to respond the way they do to the spectral color orange.
A useful concept in understanding the perceived color of a
non-monochromatic light source is the dominant wavelength, which
identifies the single wavelength of light that produces a sensation
most similar to the light source.
Dominant wavelength is roughly akin
There are many color perceptions that by definition cannot be pure
spectral colors due to desaturation or because they are purples
(mixtures of red and violet light, from opposite ends of the
spectrum). Some examples of necessarily non-spectral colors are the
achromatic colors (black, gray, and white) and colors such as pink,
tan, and magenta.
Two different light spectra that have the same effect on the three
color receptors in the human eye will be perceived as the same color.
They are metamers of that color. This is exemplified by the white
light emitted by fluorescent lamps, which typically has a spectrum of
a few narrow bands, while daylight has a continuous spectrum. The
human eye cannot tell the difference between such light spectra just
by looking into the light source, although reflected colors from
objects can look different. (This is often exploited; for example, to
make fruit or tomatoes look more intensely red.)
Similarly, most human color perceptions can be generated by a mixture
of three colors called primaries. This is used to reproduce color
scenes in photography, printing, television, and other media. There
are a number of methods or color spaces for specifying a color in
terms of three particular primary colors. Each method has its
advantages and disadvantages depending on the particular application.
No mixture of colors, however, can produce a response truly identical
to that of a spectral color, although one can get close, especially
for the longer wavelengths, where the CIE 1931 color space
chromaticity diagram has a nearly straight edge. For example, mixing
green light (530 nm) and blue light (460 nm) produces cyan
light that is slightly desaturated, because response of the red color
receptor would be greater to the green and blue light in the mixture
than it would be to a pure cyan light at 485 nm that has the same
intensity as the mixture of blue and green.
Because of this, and because the primaries in color printing systems
generally are not pure themselves, the colors reproduced are never
perfectly saturated spectral colors, and so spectral colors cannot be
matched exactly. However, natural scenes rarely contain fully
saturated colors, thus such scenes can usually be approximated well by
these systems. The range of colors that can be reproduced with a given
color reproduction system is called the gamut. The CIE chromaticity
diagram can be used to describe the gamut.
Another problem with color reproduction systems is connected with the
acquisition devices, like cameras or scanners. The characteristics of
the color sensors in the devices are often very far from the
characteristics of the receptors in the human eye. In effect,
acquisition of colors can be relatively poor if they have special,
often very "jagged", spectra caused for example by unusual lighting of
the photographed scene. A color reproduction system "tuned" to a human
with normal color vision may give very inaccurate results for other
The different color response of different devices can be problematic
if not properly managed. For color information stored and transferred
in digital form, color management techniques, such as those based on
ICC profiles, can help to avoid distortions of the reproduced colors.
Color management does not circumvent the gamut limitations of
particular output devices, but can assist in finding good mapping of
input colors into the gamut that can be reproduced.
Additive color mixing: combining red and green yields yellow;
combining all three primary colors together yields white.
Additive color is light created by mixing together light of two or
more different colors. Red, green, and blue are the additive primary
colors normally used in additive color systems such as projectors and
Subtractive color mixing: combining yellow and magenta yields red;
combining all three primary colors together yields black
Subtractive coloring uses dyes, inks, pigments, or filters to absorb
some wavelengths of light and not others. The color that a surface
displays comes from the parts of the visible spectrum that are not
absorbed and therefore remain visible. Without pigments or dye, fabric
fibers, paint base and paper are usually made of particles that
scatter white light (all colors) well in all directions. When a
pigment or ink is added, wavelengths are absorbed or "subtracted" from
white light, so light of another color reaches the eye.
If the light is not a pure white source (the case of nearly all forms
of artificial lighting), the resulting spectrum will appear a slightly
Red paint, viewed under blue light, may appear black.
Red paint is red because it scatters only the red components of the
spectrum. If red paint is illuminated by blue light, it will be
absorbed by the red paint, creating the appearance of a black object.
Structural coloration and Animal coloration
Structural colors are colors caused by interference effects rather
than by pigments.
Color effects are produced when a material is scored
with fine parallel lines, formed of one or more parallel thin layers,
or otherwise composed of microstructures on the scale of the color's
wavelength. If the microstructures are spaced randomly, light of
shorter wavelengths will be scattered preferentially to produce
Tyndall effect colors: the blue of the sky (Rayleigh scattering,
caused by structures much smaller than the wavelength of light, in
this case air molecules), the luster of opals, and the blue of human
irises. If the microstructures are aligned in arrays, for example the
array of pits in a CD, they behave as a diffraction grating: the
grating reflects different wavelengths in different directions due to
interference phenomena, separating mixed "white" light into light of
different wavelengths. If the structure is one or more thin layers
then it will reflect some wavelengths and transmit others, depending
on the layers' thickness.
Structural color is studied in the field of thin-film optics. A
layman's term that describes particularly the most ordered or the most
changeable structural colors is iridescence. Structural color is
responsible for the blues and greens of the feathers of many birds
(the blue jay, for example), as well as certain butterfly wings and
beetle shells. Variations in the pattern's spacing often give rise to
an iridescent effect, as seen in peacock feathers, soap bubbles, films
of oil, and mother of pearl, because the reflected color depends upon
the viewing angle. Numerous scientists have carried out research in
butterfly wings and beetle shells, including
Isaac Newton and Robert
Hooke. Since 1942, electron micrography has been used, advancing the
development of products that exploit structural color, such as
Color wheel: an illustrative organization of color hues in a circle
that shows relationships.
Colorfulness, chroma, purity, or saturation: how "intense" or
"concentrated" a color is. Technical definitions distinguish between
colorfulness, chroma, and saturation as distinct perceptual attributes
and include purity as a physical quantity. These terms, and others
related to light and color are internationally agreed upon and
published in the CIE
Lighting Vocabulary. More readily available
texts on colorimetry also define and explain these terms.
Dichromatism: a phenomenon where the hue is dependent on concentration
and thickness of the absorbing substance.
Hue: the color's direction from white, for example in a color wheel or
Shade: a color made darker by adding black.
Tint: a color made lighter by adding white.
Value, brightness, lightness, or luminosity: how light or dark a color
Color analysis (art)
International Commission on Illumination
Lists of colors
Lists of colors (compact version)
Pearlescent coating including Metal effect pigments
Primary, secondary and tertiary colors
^ Wyszecki, Günther; Stiles, W.S. (1982). Colour Science: Concepts
and Methods, Quantitative Data and Formulae (2nd ed.). New York: Wiley
Series in Pure and Applied Optics. ISBN 0-471-02106-7.
^ R. W. G. Hunt (2004). The Reproduction of Colour (6th ed.).
Chichester UK: Wiley–IS&T Series in Imaging Science and
Technology. pp. 11–12. ISBN 0-470-02425-9.
^ Arikawa K (November 2003). "Spectral organization of the eye of a
butterfly, Papilio". J. Comp. Physiol. A Neuroethol. Sens. Neural
Behav. Physiol. 189 (11): 791–800. doi:10.1007/s00359-003-0454-7.
^ Cronin TW, Marshall NJ (1989). "A retina with at least ten spectral
types of photoreceptors in a mantis shrimp". Nature. 339 (6220):
137–40. Bibcode:1989Natur.339..137C. doi:10.1038/339137a0. Archived
from the original on 2008-12-08.
^ Craig F. Bohren (2006). Fundamentals of Atmospheric Radiation: An
Introduction with 400 Problems. Wiley-VCH.
^ Berlin, B. and Kay, P., Basic
Color Terms: Their Universality and
Evolution, Berkeley: University of California Press, 1969.
^ Waldman, Gary (2002). Introduction to light : the physics of
light, vision, and color (Dover ed.). Mineola: Dover Publications.
p. 193. ISBN 978-0-486-42118-6. Archived from the original
^ Pastoureau, Michael (2008). Black: The History of a Color. Princeton
University Press. p. 216. ISBN 978-0691139302.
^ a b Judd, Deane B.; Wyszecki, Günter (1975).
Color in Business,
Science and Industry. Wiley Series in Pure and Applied Optics (third
ed.). New York: Wiley-Interscience. p. 388.
^ Hermann von Helmholtz, Physiological Optics – The Sensations of
Vision, 1866, as translated in Sources of
Color Science, David L.
MacAdam, ed., Cambridge: MIT Press, 1970.
^ Palmer, S.E. (1999). Vision Science: Photons to Phenomenology,
Cambridge, MA: MIT Press. ISBN 0-262-16183-4.
^ "Under well-lit viewing conditions (photopic vision), cones
...are highly active and rods are inactive." Hirakawa, K.; Parks, T.W.
(2005). Chromatic Adaptation and White-Balance Problem (PDF). IEEE
ICIP. doi:10.1109/ICIP.2005.1530559. Archived from the original (PDF)
on November 28, 2006.
^ a b Jameson, K. A.; Highnote, S. M.,; Wasserman, L. M. (2001).
"Richer color experience in observers with multiple photopigment opsin
genes" (PDF). Psychonomic Bulletin and Review. 8 (2): 244–61.
doi:10.3758/BF03196159. PMID 11495112.
^ Jordan, G.; Deeb, S. S.; Bosten, J. M.; Mollon, J. D. (20 July
2010). "The dimensionality of color vision in carriers of anomalous
trichromacy". Journal of Vision. 10 (8): 12. doi:10.1167/10.8.12.
^ Depauw, Robert C. "United States Patent". Retrieved 20 March
^ a b M.D. Fairchild,
Color Appearance Models Archived May 5, 2011, at
the Wayback Machine., 2nd Ed., Wiley, Chichester (2005).
Color Meanings by Culture". Archived from the original on
2010-10-12. Retrieved 2010-06-29.
^ Gnambs, Timo; Appel, Markus; Batinic, Bernad (2010). "
Color red in
web-based knowledge testing". Computers in Human Behavior. 26:
^ "Economic and Social Research Council – Science in the Dock, Art
in the Stocks". Archived from the original on November 2, 2007.
^ CIE Pub. 17-4, International
Lighting Vocabulary Archived 2010-02-27
at the Wayback Machine., 1987. "Archived copy". Archived from the
original on 2010-02-27. Retrieved 2010-02-05.
^ R.S. Berns, Principles of
Color Technology Archived 2012-01-05 at
the Wayback Machine., 3rd Ed., Wiley, New York (2001).
External links and sources
Find more aboutColorat's sister projects
Definitions from Wiktionary
Media from Wikimedia Commons
Data from Wikidata
Bibliography Database on
Color Theory, Buenos Aires University
Maund, Barry. "Color". In Zalta, Edward N. Stanford Encyclopedia of
"Color". Internet Encyclopedia of Philosophy.
Why Should Engineers and Scientists Be Worried About Color?
Robert Ridgway's A Nomenclature of Colors (1886) and
Color Nomenclature (1912) – text-searchable digital facsimiles
at Linda Hall Library
Albert Henry Munsell's A
Color Notation, (1907) at Project Gutenberg
AIC, International Colour Association
The Effect of
Color OFF BOOK Documentary produced by Off Book (web
Study of the history of colors
Color of Consciousness
On Vision and Colors
Spectral power distribution
Lüscher color test
Tertiary color (intermediate)
Aggressive color (warm)
Receding color (cool)
Achromatic colors (Neutral)
Tinctures in heraldry
Color analysis (art)
Color realism (art style)
Linguistic relativity and the color naming debate
Blue–green distinction in language
Color in Chinese culture
Traditional colors of Japan
Human skin color
Colorfulness (chroma and saturation)
Tints and shades
Lightness (tone and value)
Color Marketing Group
Color Association of the United States
International Colour Authority
International Commission on Illumination
International Commission on Illumination (CIE)
International Colour Association
List of colors: A–F
List of colors: G–M
List of colors: N–Z
List of colors
List of colors (compact)
List of colors
List of colors by shade
List of color palettes
List of color spaces
List of Crayola crayon colors
List of fictional colors
List of RAL colors
List of web colors
Multi-primary color display
Local color (visual art)
Index of color-related articles