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:
Sep. 07, 2004
Filed:
Dec. 18, 2002
Tetsuya Morita, Kanagawa, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
An image forming apparatus has a CIS disposed in an area where a sheet passes in such a fashion that read pixels of the CIS are arranged in a direction perpendicular to the feeding direction of the sheet. A part of the read pixels (e.g., 1000 pixels) that corresponds to {fraction (1/7)} of all the read pixels are repeatedly read with a short period (TS) to detect the position of the leading edge of the sheet being fed. After waiting a predetermined period of time after the timing of detection of the leading edge position of the sheet, a laser beam is irradiated onto a photosensitive drum to start writing an image in the subscanning direction. Further, read pixels (e.g., 6000 pixels) that corresponds to {fraction (6/7)} of all the read pixels are repeatedly read with a long period (TL) to detect the position of the side edge of the fed sheet. Based on the detected side edge position of the sheet, the amount of deviation of the sheet is calculated to thereby correct the writing start position in the main scanning direction of the sheet.