To provide a contact lens having a photochromic material within the central or pupillary area of the lens.
The contact lens having the photochromic material within the central or pupillary area of the lens and methods for manufacturing such a lens are described. In one method, a photochromic amount of at least one photochromic material is added to the pupillary region of a casting mold containing a polymerizable monomer that can be at least partially cured before and/or after the addition. Another method involves providing an amount of polymerizable photochromic monomer for the pupillary region and an amount of polymerizable non-photochromic monomer for the remainder of the contact lens in a casting mold. The photochromic and non-photochromic monomers can differ by their degree of polymerization, viscosity and/or density.
KUMAR ANIL
MALLAK FRANK P
WALTERS ROBERT W
Takaaki Yasumura
Natsuki Morishita