Patents by Inventor Chakrapani V. Varanasi

Chakrapani V. Varanasi 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).

  • Dopant-free tungsten electrodes in metal halide lamps
    Patent number: 7583030
    Abstract: A metal halide lamp having a high pressure quartz arc tube in which the electrodes are non-thoriated.
    Type: Grant
    Filed: July 21, 2004
    Date of Patent: September 1, 2009
    Assignee: Advanced Lighting Technologies, Inc.
    Inventors: Chakrapani V. Varanasi, Timothy R. Brumleve, Abbas Lamouri, Ajaypal Naruka
  • Barrier coatings and methods in discharge lamps
    Patent number: 7057335
    Abstract: The present invention includes barrier coatings and methods for reducing or preventing chemical reaction between the discharge medium and arc tube wall material in discharge lamps. The barrier coatings comprise nitride layer exposed to the discharge medium formed from one or more of aluminum, boron, scandium, yttrium, or the lanthanides. In another aspect, the present invention includes methods of forming coatings on the inner wall of arc tubes by introducing two or more precursors into the arc tube chamber and pyrolitically reacting the precursors to form layers for the coating.
    Type: Grant
    Filed: November 10, 2003
    Date of Patent: June 6, 2006
    Assignee: Advanced Lighting Technologies, Inc.
    Inventors: Tryggvi Emilsson, Timothy R. Brumleve, Chakrapani V. Varanasi