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. 09, 1988
Filed:
Apr. 22, 1986
Applicant:
Inventors:
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B / ; G02B / ;
U.S. Cl.
CPC ...
250201 ; 356444 ;
Abstract
In an auto-focus apparatus of the invention, an image sensor (e.g., a CCD) produces an image signal corresponding to an image on a microfilm. The image signal from the image sensor is encoded to a binary image signal by a binary encoding circuit. Alternation points (i.e., leading or trailing edges) of the binary image signal are counted by a counter. A system controller fetches count values from the counter, and detects an image position corresponding to a maximum count value. The system controller causes a lens driving circuit to move an imaging lens to the detected image position.