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, 2007
Filed:
Jan. 25, 2001
Noriaki Matsui, Ibaraki, JP;
Nobuo Matsuoka, Kanagawa, JP;
Toshio Hayashi, Ibaraki, JP;
Junichi Kishimoto, Chiba, JP;
Katsuhiro Ishido, Ibaraki, JP;
Satoru Kijima, Chiba, JP;
Noriaki Matsui, Ibaraki, JP;
Nobuo Matsuoka, Kanagawa, JP;
Toshio Hayashi, Ibaraki, JP;
Junichi Kishimoto, Chiba, JP;
Katsuhiro Ishido, Ibaraki, JP;
Satoru Kijima, Chiba, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In an image reading apparatus having a light source for illuminating a document, an image sensing element for outputting an electrical signal in accordance with an input light quantity, a first reference member, and a second reference member, shading correction data is acquired. A time since the light source is turned on is measured, and when the measured time does not reach a predetermined time, shading correction data is acquired by a first method using the first reference member. When the predetermined time has elapsed, shading correction data is acquired by a second method using the second reference member.