Reference Terms
from Wikipedia, the free encyclopedia

Color vision

Color vision is the capacity of an organism or machine to distinguish objects based on the wavelength (or frequency) of the light they reflect or emit.

A 'red' apple does not emit red light.

Rather, it simply absorbs all the frequencies of light shining on it except the frequencies we call red, which are reflected.

Note:   The above text is excerpted from the Wikipedia article "Color vision", which has been released under the GNU Free Documentation License.
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May 27, 2017

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