Chapter 11 Using Color Effectively
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The Anatomy of Color
Objects absorb and refl ect light. The color that you see depends on the
wavelength and frequency of the reflected waves. Red has the longest wavelength;
violet has the shortest.
Humans have trichromatic color vision. The key part of the eye responsible for
color vision is the retina. This area, at the back of the eye, contains millions of light-
sensitive nerve cells called rod and cone cells. Rod cells
enable you to see in low light. Cone cells enable you to see s
color and detail.
The tri in trichromatic refers to the three types of cone cells. i
Each type is sensitive to waves of a different part of the visible
light spectrum. “Blue cone cells” react to the shorter waves
on the blue end of the color spectrum. “Red cone cells” react
to longer waves on the red end of the spectrum. “Green cone
cells” react to medium-length waves in the green spectrum.
When light enters the eyes and hits the retina, it stimulates
the cone cells and sends electronic impulses to the brain.
The signals from the cone cells are transmitted to the brain.
In a complex process that researchers are still trying to understand, the human brain
collects and processes this and other information to produce a color image.
LINK TO SCIENCE & TECHNOLOGY
A
B
11-13
Triadic color
harmonies are
often used
in children’s
bedrooms.
Cornea Retina
Optic Nerve
Iris
Aqueous
humor
Lens