trichromatic theory
Quick Summary
The trichromatic theory, also known as the Young-Helmholtz theory, explains color vision by proposing that the human eye contains three types of photoreceptor cells called cones. Each type of cone is sensitive to different wavelengths of light: one to red, one to green, and one to blue.12
When light enters the eye, it stimulates these cones to varying degrees. The brain then interprets the combination of signals from these three cone types to perceive a specific color. For example, yellow light stimulates both red and green cones, but not blue cones, leading to the perception of yellow. This theory also helps explain color blindness as the result of one or more types of cones not functioning properly.12
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