Toric ophthalmic lenses

Abstract

A method is provided for determining, by optimization, an ophthtalmic lens for a spectacle wearer for whom an astigmatism has been prescribed, comprising the steps of: selecting a starting lens and defining a working lens to be equal to the starting lens; selecting a target lens; modifying the working lens, in order to minimize, in a plurality of directions of glance and in a reference frame associated with the eye differences in power between the working lens and the target lens and differences between astigmatism prescribed and astigmatism generated by the working lens. The invention makes it possible to avoid aberrations introduced, for an astigmatic spectacle wearer, by adding a toric surface having the prescribed astigmatism, thereby ensuring that the astigmatism effectively experienced by the wearer is the prescribed astigmatism.

Dependencies are inferred from the claim text.