Interaction of vision with optical aids*

Abstract

When vision through an optical aid is being considered it is desirable to know something of the effect of the optical quality of the aid on performance. Methods of image evaluation are discussed with particular reference to visual aids. All major methods of image evaluation are distinctly limited in predictive capability when the human observer is the final element in the chain. A model of visual performance is presented that has predictive capabilities over a wide range of situations, when used in conjunction with objective performance data relating to visual aids and the optics of the eye.