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. 18, 2009
Filed:
Aug. 18, 2003
Atsushi Kanayama, Saitama, JP;
Atsushi Kanayama, Saitama, JP;
Fujinon Corporation, Saitama, JP;
Abstract
In the auto focus system, focus evaluation values indicating a degree of sharpness of images are sought from a plurality of image pickup devices placed at positions of different light path lengths, a travel distance converging to zero as a focus of a picture-taking lens approaches a focusing position is sought by using a difference or a ratio between the two focus evaluation values, and the focus is moved to a new moving target position which is a value of a current moving target position having the travel distance added thereto so as to securely move the focus to the focusing position by stable operation of the focus suited to characteristics of the focus evaluation values.