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. 23, 2004
Filed:
Jul. 25, 2002
Applicant:
Inventor:
Goichi Oda, Shizuoka, JP;
Assignee:
Koito Manufacturing Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G05F 1/00 ;
U.S. Cl.
CPC ...
G05F 1/00 ;
Abstract
In a discharge lamp lighting apparatus , power is supplied from a DC power supply through a switch control circuit to a lighting circuit and a discharge lamp . Power is supplied to the lighting circuit through a semiconductor switch element placed in a switch control circuit and a part of the current flowing into a semiconductor switch element is detected and is compared with reference values in comparators and , thereby detecting an anomaly in the lighting circuit or the discharge lamp.