| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable color shift to be detected and corrected even during image forming operation, while effectively reducing influences of bow and the like. <P>SOLUTION: Test patterns of a plurality of colors are formed in all of an image formation area 21a and image non-formation areas 21b, 21c of an intermediate transfer belt 21, and a shift of each of the test patterns of the plurality of colors formed in the image formation area 21a and a shift of each of the test patterns of the plurality of colors formed in the image non-formation areas 21b, 21c are detected. Then, for each color, an offset value of the shift of the test pattern of each color formed in the image non-formation areas 21b, 21c with respect to the shift of the test pattern in the image formation area 21a is obtained and stored in memory 74. Based on the offset value of each color and the shift of the test pattern of each of the colors formed in the image non-formation areas 21b, 21c, a shift of the test pattern of each of the colors in the image formation area 21a can be derived. <P>COPYRIGHT: (C)2012,JPO&INPIT |
