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. 17, 2002
Filed:
Nov. 08, 2001
Yasaburo Takeji, Kyoto, JP;
Shinji Taniguchi, Kyoto, JP;
Kuniaki Nakano, Kyoto, JP;
Jiro Honda, Kyoto, JP;
Shigeyuki Mori, Kyoto, JP;
Japan Storage Battery Co., Ltd., Kyoto, JP;
Abstract
An arc tube ( ) of discharge lamp comprises a main tube body ( ) of translucent ceramic sealed with a terminal plate ( ) at both ends thereof. The main tube body ( ) comprises integrally a large diameter portion ( A), a tapered portion ( B) which is disposed at both sides of the large diameter portion ( A) and has a smaller diameter toward the forward end thereof, and a small diameter portion ( C) which is connected to the forward end of the tapered portion ( B). In this arrangement, the discharge lamp can be produced more easily than the conventional structure having a narrow portion integrally formed at both ends of a ceramic tube body, making it possible to drastically reduce cost. Further, since a low temperature zone can be only with difficulty formed inside the arc tube during discharge, the luminous efficiency can be raised.