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. 20, 1976
Filed:
Nov. 09, 1973
Canon Kabushiki Kaisha, Tokyo, JA;
Abstract
Automatic and rapid exposure control is incorporated in a camera having facilities for directing, along a common path, a pair of independent noncoincident light beams from an external object and from a separately illuminable item, such as a databearing transparency within the camera. A photoelectric circuit responsive to the total quantity of the directed light generates a proportional control voltage for operating an adjustable diaphragm to maintain a predetermined incident level of the directed light on the camera film and/or controlling the item illuminator or an auxiliary illuminator for the external object. Threshold controlled, motor-instrumented apparatus may be additionally provided to advance the film, to selectively operate a camera shutter, and to illuminate the item in response to trigger signals generated, e.g., upon the detection of the presence of the external object.