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:
Mar. 16, 2004
Filed:
Apr. 17, 2001
Takashi Tsutatani, Takatsuki, JP;
Yoshiki Kitahara, Takatsuki, JP;
Toshiyuki Shimizu, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A high pressure discharge lamp which achieves a long life of at least 3000 hours and in which variations in lamp characteristics are suppressed is disclosed. In the high pressure discharge lamp of the present invention, during manufacturing of an electrode, a covering member having a coil shape and being made of refractory metal is applied on a discharge side end of an electrode rod made of refractory metal so as to cover a circumference of the electrode rod in a vicinity of the discharge side end. The discharge side end on which the covering member is applied is fused into a semi-sphere by intermittently heat fusing the discharge side end according, for instance, to arc discharge or laser irradiation.