Patent ID: 7130551

Claim:
A color deviation detection method in which a plurality of mark sets constructed by arrangements of marks of respective colors that are lined up in the direction of movement are formed on a transfer medium in a color image forming device in which an image carrying body is rotated by an image carrying body driving system, the transfer medium is rotated by a transfer driving system, an image of a plurality of colors is formed on said image carrying body, and the image of a plurality of colors is superimposed on and transferred onto said transfer medium, and the respective marks of the plurality of mark sets are detected by sensors so that the amount of deviation of said image is detected, wherein the spacing between marks of the reference color and other colors, the spacing between marks of the same color, and the spacing between mark sets, are set as the spacing between marks within said mark sets and the spacing between mark sets, so that when the amount of color deviation is calculated for a synthesized wave comprising two or more driving irregularity frequencies that are generated by said image carrying body driving system and said transfer driving system, the calculation error caused by said synthesized wave is within a range that allows correction of the deviation of said image of a plurality of colors wherein the mark sets are arranged in groups, and a spacing between the groups is arranged such that a fluctuation irregularity per revolution of parts of the transfer medium having a circumferential length longer than the mark set is cancelled.