Method for edge grinding multifaceted lenses

Abstract

A first pattern, which has on its outer periphery a series of intersecting surfaces, is used in a conventional edger unit to control the rough grinding of a corresponding series of intersecting surfaces on the edge of a revolving lens blank. A second pattern is then inserted in the edger to control a first bevel grinding operation during which a bevel grinding wheel is caused intermittently to engage the revolving lens blank to form thereon a first plurality of angularly spaced, beveled surfaces at least one of which registers with one of the intersecting surfaces on the blank. A third pattern is then inserted in the edger to control a second bevel grinding operation during which the bevel grinding wheel forms a second plurality of beveled surfaces on the lens blank in the spaces between the first plurality, and in registry with the remainder of said flat surfaces on the blank. The result is the formation of a series of intersecting beveled surfaces having very sharp corners or facets formed at their intersections.

Dependencies are inferred from the claim text.