Patents by Inventor Robert S. H. Hum

Robert S. H. Hum 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).

  • Broadband high speed optoelectronic semiconductor switch
    Patent number: 4369371
    Abstract: The optoelectronic switch includes a photosensitive GaAs FET onto which an optical signal may be directed. The optical signal is derived from an RF modulated light source. A voltage circuit is connected to the FET to switch the FET "on" or "off" by placing a positive or zero voltage respectively on the drain. An isolation of over 70 dB is obtained in this FET switch.
    Type: Grant
    Filed: November 24, 1980
    Date of Patent: January 18, 1983
    Assignee: Canadian Patents & Dev. Limited
    Inventors: Elmer H. Hara, R. Ian MacDonald, Robert S. H. Hum, Brian S. Kawasaki