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:
Dec. 21, 1993
Filed:
Dec. 18, 1991
North American Philips Corporation, New York, NY (US);
Abstract
A single-ended electric lamp having an alkali-halide containing light source which produces ultraviolet radiation and is supported within an outer envelope by metallic support structure having an elongate support rod extending past the arc tube. A tubular cover extends over a length L1 of the support rod and the remainder of the support structure remains uncovered. A screen is interposed between the light source and an uncovered portion of the metal support structure to prevent ultra-violet radiation emitted from said light source from directly impinging on said uncovered portion. Preferably, a plurality of screens are arranged within the outer envelope to block the line of sight from the light source to any uncovered portion of the metal support structure and to reduce the quantity of reflected ultraviolet radiation reflected off the inner surface of the arc tube which impinges on uncovered portions of the metal support structure. The tubular cover and the interposed screens are comprised of a material substantially opaque to ultraviolet radiation and having a high photoelectric work function. The interposed screen(s) further reduce the production of photoelectrons and substantially reduce the voltage rise of the arc tube over the life of the lamp.