Patents by Inventor John Peter Stephenson

John Peter Stephenson 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).

  • Variable high frequency lamp controllers and systems
    Patent number: 6229270
    Abstract: A high frequency control circuit for a gaseous discharge lamp which includes a mechanically variable reactance device coupled in series with the lamp to control the current fed to the lamp. The mechanically variable reactance device is adjustable by a user to alter the intensity of the light emitted by the lamp.
    Type: Grant
    Filed: January 26, 2000
    Date of Patent: May 8, 2001
    Assignee: InDigitale Limited
    Inventors: John Peter Stephenson, George Alan Limpkin