Patents by Inventor Abraham L. De Smit

Abraham L. De Smit 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: 5990626
    Abstract: A lighting unit according to the invention comprises a supply unit (1) and a low-pressure mercury discharge lamp (2). The low-pressure mercury discharge lamp has a light-transmitting discharge vessel (3) which is provided with a luminescent layer (3) on an inner surface and which encloses in a gastight manner a discharge space (4) which is provided with a filling comprising mercury and one or several rare gases. A first (5a) and a second electrode (5b) are arranged in the discharge space, each comprising a coiling of a metal wire coated with one or several electron-emitting metal oxides. Each electrode is electrically connected to a respective current supply conductor (6a, 6b) which extends to outside the discharge vessel (3). The current supply conductors are electrically connected to the supply unit outside the discharge vessel, the unit ignites the low-pressure mercury discharge lamp in the state upon switching-on.
    Type: Grant
    Filed: February 13, 1998
    Date of Patent: November 23, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Jean J. Heuvelmans, Abraham L. De Smit