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:
Jan. 30, 2001
Filed:
Jun. 13, 1997
Mikio Horie, Tokyo, JP;
Minoru Suzuki, Tokyo, JP;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An image reading device is provided that includes a linear image sensor (such as a CCD), a contrast detecting system, and a focus condition judging system. The focus condition judging system is arranged to detect when the image reading device is in an in-focus condition based on output of the image sensor. Further, a driving mechanism is provided that moves an imaging lens or the image sensor, while the contrast detecting system monitors contrast data calculated from the output of the image sensor. An in-focus condition may be detected when the contrast data substantially reaches a maximum value. The maximum value may be a first maximum value detected during the movement controlled by the driving mechanism or may be a maximum value over a predetermined range of the controlled movement.