Abstract

Since the discovery of Stiles and Crawford in 1933 that visual sensitivity is greatest for light entering the center of the eye pupil,¹ our knowledge of photoreceptor optics has grown tremendously. Photoreceptor optics can be defined as the study of the consequences of light propagation within photoreceptor cells. The retina is a complex optical processing system whose properties play an essential role in visual information processing. The photoreceptors behave as light collectors which capture the incident light and channel the electromagnetic energy to the sites of visual absorption. During this process, the photoreceptors act as classical waveguide (or fiber optic) elements, and the retina can be thought of as an enormous fiber optic bundle. Certain aspects of the behavior of the fiber optic bundle are reflected by the psychophysically determined Stiles Crawford effect or function (SCE). The reader is referred to the literature for further details on the SCE and photoreceptor optics^2-4. It is the purpose of this paper to critically review the various theories that have been proposed to explain the SCE. More recent work on certain aspects of waveguiding in photoreceptors will be presented.

© 1993 Optical Society of America