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:
Feb. 08, 2000
Filed:
Jul. 01, 1997
Shinichiro Wada, Kawasaki, JP;
Koichi Noguchi, Machida, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An oblique line pattern is located outside of an effective image area and comprises a plurality of lines with a fixed inclination to the main scan direction. A reading unit, extending in the main scan direction, reads the oblique line pattern together with an original image which is placed in the effective image area. A setting portion is provided for an operator to set an image size change rate for the original image. A sub-scanning portion changes an original image scanning speed in a sub-scan direction according to the image size change rate. A first calculating portion sets a window on image data of the oblique line pattern obtained through the reading unit, and calculates a center of gravity of the image data in the window. A controlling portion controls movement of the window according to a value of the center of gravity obtained through the first calculating portion. A second calculating portion obtains an image reading position error for each main scan line based on the value of the center of gravity and the image size change rate.