Patents by Inventor Callum A. S. Hill

Callum A. S. Hill 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).

  • Optical switches
    Patent number: 5445767
    Type: Grant
    Filed: July 12, 1994
    Date of Patent: August 29, 1995
    Assignee: British Telecommunications Public Limited Company
    Inventors: Christoper S. Winter, Stephen N. Oliver, James D. Rush, Allan E. Underhill, Callum A. S. Hill