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. 25, 1995
Filed:
Dec. 28, 1993
Yosuke Kusaka, Yokohama, JP;
Ken Utagawa, Yokohama, JP;
Shigeyuki Uchiyama, Tokyo, JP;
Chiyuki Kuwata, Tokyo, JP;
Shozo Yamano, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A focus detecting device comprises an image forming optical system, a device for detecting the defocus amount with respect to a predetermined plane of a plurality of images, formed by the image forming optical system, of fields corresponding to a plurality of detection areas which are set beforehand, a device for classifying the plurality of detection areas into a plurality of groups on the basis of the defocus amount, a device for selecting one optimum group from the plurality of groups, and a device for determining one final defocus amount on the basis of the defocus amount corresponding to detection areas belonging to the optimum group.