[This is preliminary documentation and subject to change.]
Human vision is made possible by the presence of light sensitive cells in the eye called rods and cones. Research has shown that the rods do not seem to be involved in the perception of color in human beings. There are three different types of cones in the retina. Each type of cone detects either red, green, or blue. All other colors we see are mixtures of these three colors. For instance, white is perceived when equal amounts of red, green, and blue are seen. Black is seen when no red, green, or blue (or no light at all) is detected by the eye. The amount of color we see also depends on the strength, concentration, and position of the light source. Lighting conditions can have a profound effect on the perception of color.
In imaging systems, colors can be mixed in different ways to produce a desired result for the eye. The mixing methods most commonly used are based on the additive primary colors and the subtractive primary colors. All colors can be reproduced using either method.