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:
Aug. 31, 1976
Filed:
Feb. 05, 1975
Seiko Koki Kabushiki Kaisha, , JA;
Abstract
An exposure time control circuit for an electric shutter of a camera includes a monolithic IC having input circuitry in the form of a transistorized differential amplifier having two input terminals. A time-constant circuit develops a timing signal proportional to the brightness of the object field and applies it to one input terminal and a reference voltage signal is applied to the other input terminal to control the exposure timing. In order to enable varying the reference voltage through a wide range so that the input terminals can also be used for introducing other exposure information variables, such as input signals representative of the F-value, film sensitivity, etc., a transistor is connected between the IC and the source of electric power.