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:
May. 18, 2010
Filed:
Jan. 30, 2008
Applicants:
Yasuro Kikuchi, Hyogo, JP;
Kyosuke Fujina, Hyogo, JP;
Inventors:
Yasuro Kikuchi, Hyogo, JP;
Kyosuke Fujina, Hyogo, JP;
Assignee:
Ushio Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J 17/04 (2006.01); H01J 17/18 (2006.01);
U.S. Cl.
CPC ...
Abstract
A discharge lamp includes a cathode and an anode which face each other in an arc tube, wherein the cathode is made of tungsten in which thorium oxide is doped. The cathode has a cylindrical body portion, a tip portion having a cone shape, and a middle portion formed between the body portion and the tip portion, wherein an angle θof the tip portion is set to a range of 55 degrees≦θ≦65 degrees, and an angle θformed by side faces of the middle portion is smaller than that of the tip portion.