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:
Oct. 26, 2004
Filed:
Nov. 25, 2002
Masato Yoshida, Takatsuki, JP;
Hideaki Kiryu, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A metal halide lamp for an automobile headlight is provided, which includes an arc tube in which a pair of tungsten electrodes are provided at both ends and a metal halide as a main component of a luminescent material and xenon gas as a buffer gas are sealed, wherein the tungsten electrodes contain not more than 0.4 wt % of thorium oxide, the metal halide contains scandium iodide, and a pressure of the xenon sealed in the arc tube is at least 0.4 MPa. This makes it possible to provide a long-life metal halide lamp for an automobile headlight that can achieve a further improved lumen maintenance factor and other life characteristics during 2000 hours or more of lighting.