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.

Date of Patent:
Aug. 15, 1989

Filed:

Feb. 16, 1988
Applicant:
Inventors:

Kazuhiko Naruse, Osaka, JP;

Hidetoshi Yasumoto, Osaka, JP;

Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
355 69 ; 355 77 ; 355 68 ;
Abstract

In a light source device in which one or more light emitting tubes are adapted to emit light sequentially, there are provided one or more counters for counting the number of times of failure of light emission of the light emitting tubes, and comparator or judging circuit for comparing the number counted by the counters with a predetermined number to produce an interruption signal when the counted number is over the predetermined value, a control unit acts to interrupt the light emission of the light emitting tube in response to the interruption signal and a warning device is activated for indicating a warning in response to the interruption signal.


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