Patent ID: 7850878

Claim:
A method of retaining a volume of curable liquid in a casting mold for forming a biomedical device, the method comprising: (a) providing a first mold section having a convex first optical surface, a radially extending first flange and a plurality of ribs extending axially from one side of the first flange and extending radially to terminate at a free end; (b) providing a second mold section having a concave second optical surface and a radially extending second flange, the second optical surface including a right cylinder wall, and a shoulder axially extending from the second flange; (c) depositing the volume of the curable liquid on the second optical surface; and (d) engaging the first mold section and the second mold section by contacting the free end of each of the plurality of ribs with the shoulder to define a sealed mold cavity between the first optical surface and the second optical surface, with a portion of the right cylinder wall contacting the first optical surface.