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:
May. 03, 2011
Filed:
Nov. 21, 2006
Masahiro Hiranuma, Tokyo, JP;
Masahiro Hiranuma, Tokyo, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An image reading apparatus includes a clamp-ratio controlling unit configured to change at least one of a clamp period and a line period for each read operation mode, wherein the clamp-ratio setting unit provides a control so that a clamp ratio that is a ratio between the clamp period and the line period is constant through all read operation modes. The clamp period is a period for performing clamp processing for setting a black level to a constant, which is an absolute black reference of an analog image signal output according to a quantity of light at a time of receiving reflected light from a document, and the line period is a read period of one line in the sub scanning direction.