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. 19, 1992
Filed:
Oct. 23, 1990
Tetsushi Aoki, Hachioji, JP;
Konica Corporation, Tokyo, JP;
Abstract
An object of the invention is to provide a flash light control circuit by which a flash bulb is controlled to maintain a constant quantity of emitted light at each flash, in order to counter an insufficient exposure of a photographic object, caused by a gradual decrease of emitted light with the progress of exposures, for example, in photography with a camera on a multi exposure basis. The object is achieved by a flash light control circuit comprising a trigger circuit that impresses a trigger voltage onto a trigger terminal of the flash bulb and comprising a non-self hold type switching element connected to the trigger circuit, which is turned on for discharging energy stored in a main capacitor into the flash bulb for its consequent flashing, wherein there is provided a pulse generating circuit that impresses, onto a gate terminal of the switching element, continual pulse signals whose duty ratios increase gradually.