Patents by Inventor Alan Frederick Butler

Alan Frederick Butler 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).

  • Light emitting device
    Patent number: 6828739
    Abstract: A light emitting device includes at least a first light source which is connectable to an energy source, a second light source, detector means for detecting a failure of the first light source, and switch means, responsive to the detector means, for enabling the connection of the second light source to the energy source when the detector means detects failure of the first light source.
    Type: Grant
    Filed: May 7, 2003
    Date of Patent: December 7, 2004
    Assignee: Azoteq (PTY) LTD
    Inventors: Frederick Johannes Bruwer, Alan Frederick Butler
  • Light emitting device
    Publication number: 20040021431
    Abstract: A light emitting device includes at least a first light source which is connectable to an energy source, a second light source, detector means for detecting a failure of the first light source, and switch means, responsive to the detector means, for enabling the connection of the second light source to the energy source when the detector means detects failure of the first light source.
    Type: Application
    Filed: May 7, 2003
    Publication date: February 5, 2004
    Inventors: Frederick Johannes Bruwer, Alan Frederick Butler