My image of the retina

Abstract

The initial act for visual perception is the absorption of light in the photo-pigment of the receptor end-organs. Since both light and the nervous message have a quantal structure, any theory of visual information processing should in principle be a digital processing theory. And not only in principle, since we know for certain that in many situations the number of quanta is rather restricted, so that an over-all thermodynamic theory cannot but fail to adequately describe visual facts.