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color

 [kul´er]
1. a property of a surface or substance due to absorption of certain light rays and reflection of others within the range of wavelengths (roughly 370 to 760 nm) adequate to excite the retinal receptors.
2. radiant energy within the range of adequate chromatic stimuli of the retina, i.e., between the infrared and the ultraviolet.
3. a sensory impression of one of the rainbow hues.
primary c's a small number of fundamental colors. In visual science this refers to red, green, and blue, the colors specifically picked up by the retinal cones; mixtures of varying proportions of the primary colors will yield the 150 discriminable hues of normal human vision. In painting and printing, the primary colors are red, blue, and yellow.
color vision deficiency inability to distinguish between certain colors, popularly called “color blindness.” A complete deficiency (monochromatic vision), the total inability to see colors, is rare, affecting only one person in 300,000. Much more common are the various types of partial deficiency. The most common is red-green confusion (see deuteranopia and protanopia), which affects approximately 8 million people in the United States.

Color vision is a function of the cones in the retina of the eye, which are stimulated by light and transmit impulses to the brain. It is now thought that there are three types of cones, each type stimulated by one of the primary colors in light (red, green, and blue or violet). In red-green color vision deficiency, there is a deficiency of either red or green receptors, so that the two colors do not appear distinct from each other.

Color vision is usually tested by the ishihara test with a series of pseudoisochromatic charts or plates. (See Atlas 4, Part F.) These have a letter, number, or symbol printed in dots of one color in the midst of dots of gray or other colors. The normal person can see the symbol with no difficulty, but the person with color vision deficiency cannot distinguish it from the background.

Although color vision deficiency may occasionally result from injuries, diseases, or certain drugs, most cases are hereditary. It is usually inherited by males through the mother, who carries the trait from her father although she is not color deficient herself. In some cases, if the grandfather is color deficient and the mother carries the trait, a daughter may inherit color vision deficiency, but the ratio of men to women with inherited forms is about 20 to 1. There is no known cure for color vision deficiency.

col·or

(kŭl'ŏr),
1. That aspect of the appearance of objects and light sources that may be specified as to hue, lightness (brightness), and saturation.
2. That portion of the visible (370-760 nm) electromagnetic spectrum specified by wavelength, luminosity, and purity.
[L.]

color

/col·or/ (kul´er)
1. a property of a surface or substance due to absorption of certain light rays and reflection of others within the range of wavelengths (roughly 370–760 mμ) adequate to excite the retinal receptors.
2. radiant energy within the range of adequate chromatic stimuli of the retina, i.e., between the infrared and ultraviolet.
3. a sensory impression of one of the rainbow hues.

complementary colors  a pair of colors the sensory mechanisms for which are so linked that when they are mixed on the color wheel they cancel each other out, leaving neutral gray.
confusion colors  different colors liable to be mistakenly matched by persons with defective color vision, and hence used for detecting different types of color vision defects.
primary colors  a small number of fundamental colors; (a) in visual science, red, green, and blue, the colors specifically picked up by the retinal cones; (b) in painting and printing, blue, yellow, and red.
pure color  one whose stimulus consists of homogeneous wavelengths, with little or no admixture of wavelengths of other hues.

col·or

(kŭl'ŏr)
1. That aspect of the appearance of objects and light sources that may be specified as to hue, lightness (brightness), and saturation.
2. That portion of the visible (370-760 nm) electromagnetic spectrum specified as to wavelength, luminosity, and purity.
Synonym(s): colour.
[L.]

color

1. a property of a surface or substance due to absorption of certain light rays and reflection of others within the range of wavelengths (roughly 370 to 760 nm) adequate to excite the retinal receptors.
2. radiant energy within the range of adequate chromatic stimuli of the retina, i.e. between the infrared and ultraviolet.
3. a sensory impression of one of the rainbow hues.

broken color
in decribing coat color, a solid color broken up by another color, usually white.
coat color
color dilution
reduction of the concentration of the color pigment in tissue; most important in hair and other fiber coats, in the skin and in the ocular iris.
color dilution alopecia
see color mutant alopecia.
color flow Doppler
color pigments
the pigments influencing skin color are melanin, melanoid, oxygenated hemoglobin, reduced hemoglobin, carotene.
color radical
color vision
the domestic animal species have limited color vision, the best perception being in bright light. Birds probably have the best, cattle and sheep the least, if any.

Patient discussion about color

Q. Why is the color draining from my eyes?! When I was little I had rich shiny cobalt blue eyes! As I grew up they faded or just started to dim in color. Being partially blind you can see in my left eye the its a really light color and creamy instead of my deep blue color... Why does my eye color dim?! I didnt think going blind had anything to do with the color of my eyes changing... Or is it something else?! Please, and thank you!

A. depends on your blindness, if it is caused by your cornea changing (corneal opacity)- it'll change your eye color to a cloudy white. it can also be caused by cataract.
are those the reason of your blindness?

Q. If someone as alcoholism do there eyes change color? My husband says his work mate told him that if you’re an alcoholic your eyes can change color. As an example If you have blue eyes they become a darker blue because of something in your bloodstream?. I think my husband’s workmate is winding my husband up, or is he telling the truth?

A. That is an untruth. The color of the eyes in an alcoholic will not change color. The only thing in the eyes that will change color are the corneas (the whites of the eyes) they will turn yellow due to jaundice and probably cirrhosis of the liver. The skin will also turn yellow with the jaundice.

Q. What exactly is PPD? I heard it is a substance in hair color and that some women are allergic to it How can I know if I’m allergic to it?

A. That sounds nasty... so how can I know if i'm allergic to it or not?

More discussions about color
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