Lens precursor with features for the fabrication of an ophthalmic lens

Abstract

This invention provides for the fabrication of ophthalmic lenses via the utilization of DMD shows and/or DMD files. More specifically, the use of the DMD shows and/or DMD files to generate lens precursor designs comprising described features to form part of a substructure for the fluid reactive media portion of the lens precursor and wherein the lens precursor can generate particular ophthalmic lens designs in a free-form manner using methods described herein.

What is claimed is: 
     
         1 . A method for forming a lens precursor comprising:
 forming a lens precursor form having a concave, optical quality first surface; an opposing second surface, wherein the first and second surfaces are joined at a lens edge that defines the outer perimeter of the lens precursor form; and a lens edge feature that is present on the second surface and along or substantially adjacent to at least part of the lens edge, said lens edge feature forming a projection extending outwardly beyond said opposing second surface; and   allowing a fluent lens reactive media to flow unconstrained over said opposing second surface of said lens precursor form until it reaches a minimal surface tension state, wherein said flowing of said fluent lens reactive media is influenced only by a shape and topology of said opposing second surface including said lens edge feature, and wherein said lens edge feature either prevents the flow of the fluent lens media over the edge of the lens, or controls the flow of the fluent lens media over the edge of the lens.   
     
     
         2 . The method according to  claim 1 , wherein said lens edge feature decreases in thickness from a maximum with increasing distance from the lens edge, thereby forming an inwardly-facing lens edge feature. 
     
     
         3 . The lens precursor form of  claim 2 , wherein the inwardly-facing lens edge feature is concave in a plane containing the axis of the lens. 
     
     
         4 . The method according to  claim 1 , wherein a maximum thickness of the lens edge feature is spaced from the lens edge. 
     
     
         5 . The method according to  claim 1 , wherein said lens edge feature is continuous around the lens precursor form. 
     
     
         6 . The method according to  claim 1 , wherein the lens edge feature is present in discrete, non-continuous zones. 
     
     
         7 . The method according to  claim 1 , wherein a height of the lens edge feature is between 0.001 mm and 1 mm.