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:
Sep. 28, 1999
Filed:
Dec. 09, 1996
Franciscus M Snijkers, Eindhoven, NL;
Paul J Van Rijswijck, Eindhoven, NL;
Albert Manenschijn, Eindhoven, NL;
Rene C Weenink, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A cathode ray tube is provided with an electron gun which comprises a cathode structure which contains an electron-emitting material at an end portion and in which a heating element of bifilarly wound wire is accommodated. Except in the vicinity of the ends of the wire, said wire is provided with an electrically insulating layer (46) whose radius decreases, near the transition between the covered wire and the uncovered ends, by at least 15%, preferably at least 30%. Preferably, the layer (46) having the reduced radius continues for at least 100 .mu.m in the direction of the transition (54). The distance between the transition (54) and the electric connection (61) is smaller than 250 .mu.m, preferably smaller than 150 .mu.m. As a result, the number of uncovered turns between the electric connection (61) and the transition (54) is reduced to below five.