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. 09, 2000
Filed:
Apr. 30, 1998
Applicant:
Inventors:
Yoshiro Ichihara, Yokohama, JP;
Yukio Odaka, Kawasaki, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
396205 ; 396206 ;
Abstract
In a flash device of the kind preventing a main capacitor from being overcharged by inhibiting a charging action on the main capacitor when the voltage of the main capacitor reaches a predetermined first level, detecting the voltage of the main capacitor by a voltage reference diode and allowing light emission when the voltage of the main capacitor reaches a second level which is higher than the first level, an element having a negative temperature characteristic is connected in series to the voltage reference diode. The arrangement ensures an apposite operation of the flash device irrespective of temperature variations.