| 摘要 |
PROBLEM TO BE SOLVED: To accurately correct a color slurring caused by the eccentricity of a photoreceptor drum and a driving roller, even if a large-sized storage device and a complex arithmetic unit are not used, in a driven-driving system tandem type. SOLUTION: The circumferential speed information Aout of the photoreceptor drum and the speed fluctuation information Bout of a carrying belt are measured, while the driving roller is driven at a fixed rotational speed. Corrected circumferential speed data Px obtained in such a manner that the speed fluctuation information Bout of the carrying belt is subtracted from the measured circumferential speed information Aout of the photoreceptor drum is stored by one rotation of the photoreceptor drum. Further, the circumferential speed data Qx of the carrying belt is stored by one rotation of the driving roller. Writing for a scanning line is executed while the line number of bit map data read so as to correct the positional deviation of the scanning line, which is based on the circumferential speed fluctuation of the photoreceptor drum is corrected by using the stored corrected circumferential speed data Px and circumferential speed data Qx. |
