Patents by Inventor Punt F. J. Willibrordus

Punt F. J. Willibrordus 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 vapor discharge lamp with reflective layer having prescribed bimodal distribution of large and small particles
    Patent number: 5514932
    Abstract: A low-pressure mercury vapor discharge lamp having a discharge vessel which is sealed in a gastight manner and encloses a discharge space which contains a filling of mercury and rare gas and in which an electric discharge is maintained. A portion of a surface of the discharge vessel facing the discharge space has a reflector layer of aluminum oxide particles which includes a comparatively great porportional weight of larger particles with a median diameter of 0.25 to 0.80 .mu.m and a comparatively small proportional weight of smaller aluminum oxide particles with a median diameter of 0.01 to 0.02 .mu.m, which smaller particles are present dispersed among the larger particles. The product of the median of the overall particle size distribution and the specific surface of all particles taken together is at least 4.times.10.sup.-3 m.sup.3 /kg. As a result, the lamp has a comparatively high luminous efficacy.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: May 7, 1996
    Assignee: U.S. Philips Corporation
    Inventors: Punt F. J. Willibrordus, Baaten P. M. Johannes