DEVIATION AMOUNT COMPUTING DEVICE, DEVIATION AMOUNT COMPUTING METHOD, AND DEVIATION AMOUNT COMPUTING PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a deviation amount computing device, method, and program which are able to compute an amount of deviation quickly even when an image formation process is being performed.;SOLUTION: A deviation amount computing device is for use in an electrophotographic color image forming apparatus that has a printing medium transport belt or intermediate transfer belt, scans a light beam corresponding to an image signal, thereby forming an image on an image carrier, and computes an amount of deviation of the image. The computing device includes: a first computing means configured to read a detection pattern formed on the be a second computing means configured to measure a scanning time between a start and an end of one scan of a light beam, thereby computing a deviation amount containing both an amount of deviation in the main scanning direction and an amount of deviation in the running direction of the belt member in a mixed manner; and a third computing means configured to calculate an amount of deviation in the main scanning direction and an amount of deviation in the running direction of the belt member.;COPYRIGHT: (C)2009,JPO&INPIT