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:
Apr. 10, 1984
Filed:
Aug. 30, 1982
Saburo Numata, Urawa, JP;
Fuji Photo Optical Co., Ltd., , JP;
Abstract
An auto strobe control circuit comprising a flash stopping signal generating circuit for measuring the luminance of an object exposed to light emitted from a flash tube by a photometric circuit, sending the obtained photometric value, film sensitivity information and aperture information to an operational amplifier to subject them to an arithmetic operation, and generating a flash stopping signal when the value calculated by the arithmetic operation, reaches a predetermined light amount. The photometric circuit essentially consists of a photoelectromotive force type light receiving element and a log-conversion diode connected in series with a constant-voltage circuit, and a temperature compensation circuit connected with the log-conversion diode. The photometric value is sent from a connection point between the light receiving element and the log-conversion diode to the operational amplifier. A voltage follower is positioned between the temperature compensation circuit and the log-conversion diode.