A NOTE ON ECOLOGICAL OPTICS

Publisher Summary This chapter discusses the concept of ecological optics. The established branches of optics are appropriate for the study of visual sensations but not for the study of visual perception. Visual perception is not based on having sensations but on attention to the information in light. The essence of ecological optics is the demonstration that there is information in ambient light. However, the common assumption of physical, geometric, and physiological optics is that there is no information in light, that is, no information about the ordinary things from which the light is reflected. Students of traditional optics, like students of sensory physiology, tend to be impatient with what they consider philosophical issues. They like to believe that science progresses by the accumulation of facts and not by polemics. The heart of ecological optics is the concept of the ambient optic array at a point of observation. The ambient array needs to be distinguished from the ambient light. The former constitutes stimulus information; the latter constitutes stimulus energy. The purpose of ecological optics is not to explain the visibility of stars, lighthouses, or spectral colors. It is not to improve the design of optical instruments or the prescribing of spectacles. It is not concerned with dazzle or afterimages. Its purpose is to explain how animals see their environment, chiefly illuminated surfaces. Ecological optics is less concerned with seeing light than with the seeing of things by means of light.