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. 28, 2008
Filed:
Oct. 13, 2005
Takeshi Fukuyo, Shizuoka, JP;
Michio Takagaki, Shizuoka, JP;
Akira Homma, Shizuoka, JP;
Shinichi Irisawa, Shizuoka, JP;
Takeshi Fukuyo, Shizuoka, JP;
Michio Takagaki, Shizuoka, JP;
Akira Homma, Shizuoka, JP;
Shinichi Irisawa, Shizuoka, JP;
Koito Manufacturing Co., Ltd., Tokyo, JP;
Abstract
In a mercury-free arc tube, electrodes are configured by electrode rods heat-treated at 1,200 to 2,200° C. in a vacuum atmosphere, and which have a thickness of 0.3 mm or more. The size (radius R) of a residual compression strain layer formed around the electrode rod is set to be ¼ or less of the width D of the pinch seal portion. A glass layer outside the residual compression strain layer is thickened, thereby enhancing the strength of the pinch seal portion.