Patents by Inventor Roger J. Hoffman

Roger J. Hoffman 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).

  • Patent number: 5824276
    Abstract: An apparatus and method for uniformly contacting an article with a treatment solution. Preferred embodiments are methods of uniformly tinting of contact lenses or uniformly surface modifying contact lenses. The method involves suspending the lens in the treatment solution by application of fluid flow, preferably sinusoidal or pulsed, in a direction opposite the stagnant force (i.e., sum of buoyancy and gravity forces) on the article. The fluid flow prevents the lens from contacting the container structure for periods sufficient to cause non-uniform treatment conditions, while continuously mixing the treatment solution to maintain uniform concentrations throughout.
    Type: Grant
    Filed: April 8, 1996
    Date of Patent: October 20, 1998
    Assignee: CIBA Vision Corporation
    Inventors: Robert A. Janssen, Barbara L. Heyl, Roger J. Hoffman, Thomas E. Shank
  • Patent number: 5665420
    Abstract: An apparatus and method for uniformly contacting an article with a treatment solution. Preferred embodiments are methods of uniformly tinting of contact lenses or uniformly surface modifying contact lenses. The method involves suspending the lens in the treatment solution by application of fluid flow, preferably sinusoidal or pulsed, in a direction opposite the stagnant force (i.e., sum of buoyancy and gravity forces) on the article. The fluid flow prevents the lens from contacting the container structure for periods sufficient to cause non-uniform treatment conditions, while continuously mixing the treatment solution to maintain uniform concentrations throughout.
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: September 9, 1997
    Assignee: Ciba Vision Corporation
    Inventors: Robert A. Janssen, Barbara L. Heyl, Roger J. Hoffman, Thomas E. Shank
  • Patent number: 5607518
    Abstract: Methods of deblocking a polymeric article from a mold and/or removing undesirable materials from a polymeric article by applying supercritical fluids to the polymeric article. A preferred process is the treatment of ophthalmic lenses, such as contact lenses. Supercritical fluid, composed primarily of carbon dioxide, is applied to a contact lens affixed to a mold subsequent to the polymerization step. The application of supercritical fluid (SCF) causes the lens to efficiently and consistently separate from the mold, removes undesirable materials such as unreacted monomer, oligomers, or residual solvents from the lens core, and/or cleans the lens surface of adhered debris.
    Type: Grant
    Filed: February 22, 1995
    Date of Patent: March 4, 1997
    Assignee: Ciba Geigy Corporation
    Inventors: Roger J. Hoffman, Wilson L. Terry, Jr.