Eye and Retina

Color Constancy M. Ebner 2007 John Wiley Sons, Ltd 

The cones are used for color vision in bright light conditions (photopic vision), whereas the rods are used when very little light is available (scotopic vision). 

The irradiance E falling onto the receptor when viewing a matte surface can be considered to be the product between the reflectance of the object R (the percentage of incident light that is reflected by the object) and the irradiance L falling onto the object. 

The details (such as the dependence of the reflected light on the orientation of the surface) are deferred until Section 3.3. Therefore, the energy Q, can be modeled by 

Some colors mix well while others do not (Tovee 1996). For instance, one cannot speak of a greenish-red. If we mix red and green, we get yellow. Yellow seems to mix well with 

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Fig. 1. Schematic diagram of a horizontal cross-section of the eye and retina (A) and of the photoreceptor cells (B).

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