Patents by Inventor Pieter J. C. Van Der Wel

Pieter J. C. Van Der Wel 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).

  • Low-pressure mercury lamp with specific electrode screens
    Patent number: 6049164
    Abstract: A discharge vessel (10) encloses a discharge space (12) in a gastight manner, electrodes (21a, 21b) being arranged in the space and having a first (22a, 22b) and a second fastening (22a', 22b'). At least one of the electrodes (21a) is surrounded by a screen (23) which has a smallest width W, in a plane transverse to the tube axis (11) and transverse to the direction from the first (22a) to the second fastening (22a'), which width is smaller than the distance D between the fastenings (22a, 22a'). The screen (23a) has a length L in the direction of the tube axis (11) which lies between once and three times the smallest width W. The lamp consumes comparatively little mercury in the case of cold ignition.
    Type: Grant
    Filed: March 25, 1998
    Date of Patent: April 11, 2000
    Assignee: U.S. Philips Corporation
    Inventors: Wilhelmus M. P. Van Kemenade, Pieter J. C. Van Der Wel