FIGURE 4.8 Color Mixing The millions of shades of color that humans can perceive are products not only of a light’s wavelength, but also of the mixture of wavelengths a stimulus absorbs or reflects. Colored spotlights work by causing the surface to reflect light of a particular wavelength, which stimulates the red, blue, or green photo-pigments in the cones. When all visible wavelengths are present, we see white.

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