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:
Oct. 08, 1991
Filed:
Mar. 21, 1990
Takashi Baba, Atsugi, JP;
Yukichi Niwa, Atsugi, JP;
Minoru Yoshii, Tokyo, JP;
Takako Watanabe, Atsugi, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In an automatic focusing apparatus, a focus detecting device having detecting means for detecting the width of the edge part of the image of an object to be photographed and discriminating means for discriminating a focused state on the basis of the size of the detected width is arranged to determine by the discriminating means the apparatus to be out of focus when the width of the edge part of the object image is wide and to be in focus when the width of the edge part is narrow, so that the focus detecting device can operate without being affected by difference in the kind and the contrast of the object to be photographed.