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:
Jan. 20, 2004
Filed:
Nov. 22, 2000
Georg Gaertner, Aachen, DE;
Wim Van Den Hoek, Eindhoven, NL;
Koninklijke Philips Electronics N.V., Eindhoven, NL;
Abstract
A gas discharge lamp comprising an electrode including a carrier of an electrode metal, selected from the group formed by tungsten and tungsten-containing alloys, and a first coating of a first electron-emitting material, which material comprises an alkaline earth metal oxide, selected from the group formed by calcium oxide, strontium oxide and barium oxide, and a rare earth metal oxide, selected from the group formed by scandium oxide, yttrium oxide and europium oxide, in a quantity a that ranges from 0.1 to 10 wt. % by weight, is characterized by a longer service life, a higher resistance to poisoning and a robust manner of coping with a rapid succession of switching operations, as well as a short ignition stage.