Patents by Inventor Lisa A. Pettigrew

Lisa A. Pettigrew has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Oxygen permeable bifocal contact lenses and their manufacture
    Patent number: 5170192
    Abstract: An oxygen permeable bifocal contact lens with a Dk of at least 10.times.10.sup.-11 in which a distance vision portion having a refractive index of not more than 1.49 is formed as a preform in which there is provided a recess, and a near distance vision portion having a refractive index of at least 1.540 is formed by filling the recess with a monomer mixture and polymerizing. It is preferred that the distance vision portion be formed as an interpenetrating network copolymer by partially polymerizing one monomer mixture to a predetermined relative viscosity and then adding a second monomer mixture and copolymerizing the resulting mixture. The near distance vision portion may also be formed as an interpenetrating network in the same manner.
    Type: Grant
    Filed: November 29, 1990
    Date of Patent: December 8, 1992
    Assignee: Pilkington Visioncare, Inc.
    Inventors: Lisa A. Pettigrew, Donald J. Ratkowski, William J. Burke, Joseph I. Weinschenk, III