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:
Mar. 12, 2013
Filed:
Nov. 24, 2009
Hajime Tsukahara, Kanagawa, JP;
Tohru Kanno, Kanagawa, JP;
Hajime Tsukahara, Kanagawa, JP;
Tohru Kanno, Kanagawa, JP;
Ricoh Company, Limited, Tokyo, JP;
Abstract
When a light source is in off state, a gray level of image data on a pixel-by-pixel basis is generated as a first black level and an average of gray levels of a portion of the image data corresponding to optical black image portions of sensor chips is generated as a second black level. After that, when an image of an original is read, an average of gray levels of the black image data on a line-by-line basis is generated as a third black level. The first black level is subtracted from a gray level of the image data on a line-by-line basis (an offset correction), and a difference between the third black level and the second black level is added to a gray level of the image data after being subjected to the subtraction on a line-by-line basis.