Patents Assigned to Softfocal Co., Inc
  • Patent number: 6176579
    Abstract: Bifocal contact lenses are lenses with two zones having different optical powers, or more than two zones in which case they are also called multifocal lenses. Concentric bifocal contact lenses have two or more annular power zones with a connection that presents optical problems. These optical problems are solved in my invention by connecting the spherical power zones for far and near viewing by a unique toric transition zone. The toric transition zone provides a smooth and continuous slope that will not produce visual jump where it joins with the power zones. There is only one toric curve with the correct properties for each pair of bifocal power zone parameters, consisting of the power zone radii and widths.
    Type: Grant
    Filed: July 7, 1999
    Date of Patent: January 23, 2001
    Assignee: Softfocal Co., Inc
    Inventor: Robert B. Mandell