Patent ID: 6746118
Filing Date: 2004-06-08
Classification: G02C

Abstract:
A bifocal contact lens formed of at least one optical material and comprising,a back surface of generally concave shape, a front surface of generally convex shape, said front surface joining said back surface at an edge perimeter, said contact lens comprising a primary prism that affects positioning and rotation of said contact lens, said front surface comprising a secondary prism that is located centrally and a lenticular area that is located peripherally, said secondary prism comprising a base that extends in an external direction from the portion of said lenticular area that is contiguous with said base of said secondary prism, said secondary prism area comprising prism power and correction for refractive error, whereby in wearing said contact lens on said eye, a portion of said lenticular area occupies a position beneath the lower lid of said eye, and said base of said secondary prism occupies a position approximately at the margin of said lower lid, so that generally vertical movements of said lens are imparted as a result of forces from said lower lid to said base, during generally vertical movements of said eye.