The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 15, 1997
Filed:
Sep. 21, 1995
Petrus H Antonis, Eindhoven, NL;
Jacob Schlejen, Morgantown, WV (US);
Leonardus U Konings, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An illumination unit comprises an electrodeless low-pressure discharge-lamp and a high-frequency power supply unit. The lamp has a gastight closed discharge vessel with an ionizable fill and a coil with turns of a primary and a secondary winding around a core of soft-magnetic material. The power supply unit has input terminals, a first output terminal, electrically neutral with respect to ground, that is connected to a first end of the primary winding, and a further output terminal that is connected to a second end of the primary winding. During nominal lamp operation the primary winding excites a high-frequency magnetic field that maintains an electrical discharge in the discharge vessel and that induces in the secondary winding a potential drop in the direction of a first, with respect to the electrically neutral end, to a second free end that varies in a sense opposite to the potential drop from the first to the second end in the first winding. At least one of the windings has at its second end at least one turn that extends beyond the core, which facilitates the ignition of the lamp.