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. 29, 2003
Filed:
Dec. 27, 2000
Junming Tu, Bath, NY (US);
Kevin Dombrowski, Painted Post, NY (US);
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
High lumen output quartz metal halide lamps are provided which comprise a vacuum outer fill, and a silicon nitride CVD coating on the outside of the quartz arc tubes (discharge tubes). Instead of nitrogen filled outers, vacuum lamp outers are used to reduce energy loss (since heat conduction loss is reduced) and to increase lumen output. Additionally, only the outside of the arc tubes is coated with silicon nitride, without coating the metal components. This reduces or blocks sodium diffusion through the quartz walls. The silicon nitride coating also retards migration of the trace hydrogen from the lamp outer into the arc tube. At least about a 10% increase, and preferably a 15% increase in lumen output is realized by using a vacuum lamp outer instead of the nitrogen fill outer conventionally used for the traditional quartz fill lamps. The heat conduction loss is reduced and the lamp efficiency is increased significantly.