Patents by Inventor Frederik H. Alkema

Frederik H. Alkema 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).

  • Electronic flashgun
    Patent number: 4333127
    Abstract: Electronic flashgun having a rotatable reflector accommodating a discharge lamp, the reflector having means to move filters in front of the flash discharge lamp. The filters are inserted via an elongate coverable aperture (5) in an end partition (2a).
    Type: Grant
    Filed: September 22, 1980
    Date of Patent: June 1, 1982
    Assignee: U.S. Philips Corporation
    Inventors: Frederik H. Alkema, Meerten Luursema
  • Compact fluorescent reflector lamp
    Patent number: D302472
    Type: Grant
    Filed: October 28, 1986
    Date of Patent: July 25, 1989
    Assignee: North American Philips Lighting Corp.
    Inventors: Wallace T. MacDonald, Robert E. Cassidy, Harish F. Gandhi, Antonius J. M. Van Hees, Frederik H. Alkema