Patent ID: 6024448
Filing Date: 2000-02-15
Classification: B29D,B41M,G02C

Abstract:
A contact lens comprising a front surface, a back surface and an identifying mark on at least one of said front surface and said back surface, wherein said identifying mark comprises a depressed region having a top and a bottom, said top of said depressed region being where the surface of said depressed region meets the surface of either said front surface or said back surface of said contact lens, the remainder of the surface of said depressed region being said bottom of said depressed region, wherein for at least 50 percent of the total surface area of said bottom of said depressed region, a cross-section of said depressed region comprises at least two intersecting concave surfaces, and said intersecting concave surfaces form an angle .beta., with the proviso that said angle .beta. cannot be 0, and further wherein said cross-section comprises an overall width or diameter and maximum depth.