Trichromatic Theory

Related Concepts

Chromaticity; Color Constancy

Definition

Trichromatic theory is the conceptual framework by which human vision matches the color of any test light to that of an additive mixture of the spectra of three primary lights in appropriate proportions. For highly chromatic colors, such a match might require one of the primary lights to mix with the test light instead of with the other primaries; the algebra of adding the light spectra would represent this condition as subtraction.

Background

The basic correctness of trichromatic theory (acknowledged at least since Thomas Young in 1802) underlies the success of such technologies as color photography and television, both of which need only three primaries to produce acceptable color rendition. The amounts of three primary lights needed to match a test light are called the tristimulus valuesof that test light, and are used to specify color quantitatively. Two lights with different spectra and the same tristimulus values are...