Influence of asphericity of the anterior corneal surface in visual performance

In this work, we study the accuracy of the standard model of the anterior c orneal surface, which assumes that the cornea and the other eye surfaces ar e conicoid. For this, we add a new asphericity term for modelling the anter ior cornea and we study whether this has a significant influence on visual performance evaluating the monochromatic modulation transfer function (MTF) . In the MTF computations, we include the spherical aberration and we use b iometric data provided by an schematic eye model. The results confirm that the conicoid model for the eye surfaces may be valid for the posterior corn ea, anterior and posterior lens, but not for the anterior cornea in order t o make highly accurate predictions of visual performance. This information should be considered in eye-schematic models and have practical implication s for processes such as refractive surgery, based on modelling the anterior cornea, and contact-lens design.