Patent ID: 8697770
Filing Date: 2014-04-15
Classification: B29D,G02B,G02C

Abstract:
1. A method for making a photochromic, hydrogel contact lens comprising: dosing a first hydrogel lens composition to a front contact lens mold part; wherein the first hydrogel lens composition comprises at least one contact lens monomer and a photochromic material; dosing a second hydrogel lens composition to said contact lens mold part on the top of the first composition wherein the first composition has a viscosity greater than the viscosity of said second contact lens composition; positioning a second mold part proximate to the first mold part thereby forming a lens cavity with the first lens composition and the second composition within the lens cavity, and curing said first and second compositions to form said hydrogel contact lens having an actual sagittal depth within about 100 microns of a design sagittal depth, and wherein said first and second lens compositions, when cured, have expansion factors which are within 10% of each other.