Tri-color theory
The three-color theory or trichromatic theory or Young-Helmholtz theory is a historical theory of color perception in the human eye . It was largely developed by Hermann von Helmholtz around 1850 , based on an older theory by Thomas Young . The theory describes the three basic colors red , green and blue .
For the current state of knowledge of physiology, see the article Color Perception .
Helmholtz had observed that any other color (within a color gamut spanned by the three primary colors ) can be mixed from colored light of three primary colors (this is still the functional principle of all color television screens and color monitors today). Similarly, he suspected that there are also three types of receptors in the eye . They react differently to light of different wavelengths . Gray and white are perceived when all three types of receptors are equally excited. Black is perceived when none of the receptor types are stimulated.
In fact, at the end of the 19th century, three different color sensory cells were detected in the retina . The color ametropia , which occurs when one of the three cell types is genetically missing, also fits in well with the trichromatic theory. Other phenomena could be better explained by the opposite color theory. The theoretical controversy was very fruitful for physiology ; numerous scientists of the 19th century commented on color perception.
Hermann Graßmann formulated this fact in his first law .
Web links
- Bruce MacEvoy: Trichromatic mixtures. In: Handprint. Color Vision. Light and the eye . - handprint.com (English).
Individual evidence
- ^ Hermann Helmholtz : Gesammelte Schriften III.2, Olms-Weidmann, 2003, Fig. 21.