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:
Mar. 21, 1978
Filed:
May. 06, 1976
Yukiyasu Nishikawa, Kawagoe, JA;
Takuo Itagaki, Tsurugashima, JA;
Asahi, , JA;
Abstract
A closed-loop circuit arrangement sequentially operates in a tracking mode before the shutter of a single lens reflex camera is actuated, and then in a holding mode after the shutter is actuated. The circuit arrangement receives from a conventional photoelectric circuit a first analog signal that instantaneously represents exposure time so long as light entering the camera impinges on the photoelectric circuit. A register in the circuit arrangement provides a digital multi-bit signal that is converted to a second analog signal. The first and second analog signals are compared to produce an error signal used during the tracking mode in controlling the register so that the digital multi-bit signal varies until the first and second analog signals represent the same exposure time. After the shutter is actuated, the register serves as a memory thereby causing the second analog signal to statically represent exposure time.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile