Patents by Inventor Mark J. L. M. Van Dommelen

Mark J. L. M. Van Dommelen 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).

  • Patent number: 5461277
    Abstract: A high pressure discharge lamp includes a sealed lamp vessel (1) having a quartz glass wall (2) enclosing a discharge space (3). Metal foils (4) are embedded in the wall, connected to electrode rods (6), and have a circumferential coating (7) of quartz glass at least adjacent the metal foil. The coating has a firm adherence to the rod. It may comprise in its boundary (7') adjoining the rod/coating interface an addition, e.g. selected from a group comprising thorium, yttrium, hafnium. Alternatively, rhenium may be present at the surface of the rod, giving an interlocking configuration of the rod and its coating. Due to a strong adherence of the quartz glass to the rod upon completing a seal, and due to large differences in expansion coefficients, the coating is torn off from the wall so as to be mechanically loose from the wall. The coating prevents premature failure of the lamp caused by leakage.
    Type: Grant
    Filed: October 5, 1992
    Date of Patent: October 24, 1995
    Assignee: U.S. Philips Corporation
    Inventors: Petrus M. G. Van Gennip, Mark J. L. M. Van Dommelen