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:
Jul. 19, 1994
Filed:
Oct. 26, 1992
Jagannathan Ravi, Elmira, NY (US);
Gerard Van Bockstal, Lier, BE;
Go Suzuki, Aichi, JP;
Kouji Shirasu, Yamanashi, JP;
North American Philips Corporation, New York, NY (US);
NGK Insulators, Ltd., Nagoya, JP;
Abstract
A high pressure discharge lamp having a thick film resistor comprising a plurality of resistive elements. A first resistive element is included in a starting circuit for the lamp and a second resistive element is in series with the arc tube during lamp operation for flicker elimination. The integral thick film resistor facilitates mounting and connection of the resistor elements within the lamp envelope. Favorably, the resistor substrate has a surface emissivity of greater than about 0.5, and preferably greater than about 0.9, to provide sufficient radiation cooling within an evacuated outer lamp envelope to prevent resistor failure while keeping the size of the resistor small enough for use as a component in an HID lamp. Additionally, a suitable coating of low vapor pressure thickness covers the solder connecting the metallic resistor terminals to the substrate to prevent evaporation of the solder and its deposition on the inner surface of the outer lamp envelope.