NOTE: This definition was changed in RP-16-17 Addendum 4. Deletions have a strike-through. New text is bold.
Retinal receptors with three distinct spectral responses that dominate the retinal response when the luminance level is high and provide the basis for high resolution visual acuity and the perception of color. Cones are highly concentrated within the fovea and less concentrated across the remainder of the retina.« Back to Definitions Index