Abstract

A spatial frequency model for vision requires that the diffraction pattern representations of the Fourier transformed equivalent of object information at the focal surfaces of two quasi-monochromatic wavelength intervals are coincident with rod and cone outer receptive segments.¹ A focal length and wavelength dependence is linked to the size of the Airy diffraction pattern, coherent transfer functions, and variable-sized patches at the retina. Airy diameter couples wavelength over pupil diameter. This, and the hardwiring of the retinal neurophysiology, indicate that visual tasks with changes of pupillary diameter require wavelength changes to maintain a more nearly constant relationship of Airy pattern to nerve network. Hyperopia is then a system stuck in a condition of long focal length, for which appropriate therapy consists of convergence and brightness-dependent exercises which couple in accommodation increases. Myopia is then a condition of too short a focal length, with reverse treatment strategy required. Presbyopia requires a combination of these approaches.

© 1986 Optical Society of America