Patents Represented by Attorney Gregory L. Nelson
  • Patent number: 4254065
    Abstract: The present invention relates to lenses and more particularly relates to the method of forming prescription contact lenses of the single vision, bicurve, lenticular, bifocal and other types by injection molding. The lens is formed from a blank having a cylindrical configuration with a concave or convex surface. The concave or convex surface forms a surface such as the base curve of the completed lens minimizing finishing operations. The lens blanks are supplied to the practitioners in a series having a completed or substantially completed curved surface. The lenses are formed by injection molding closely controlling parameters such as injection pressure, time, and temperature to avoid internal stress in the lens.
    Type: Grant
    Filed: April 4, 1979
    Date of Patent: March 3, 1981
    Inventor: Donald J. Ratkowski