| 摘要 |
PROBLEM TO BE SOLVED: To prevent the deterioration of a photosensitive body and the wasteful consumption of toner by preventing the unnecessary irradiation of laser beams to the photosensitive body in the varying operation of pixel density. SOLUTION: When a pixel density setting instruction is received (S1), present pixel density and pixel density to be set are compared with each other (S2) and when both pixel density are the same, the rotational speed of a polygon motor is not changed so that the timing of /SYNCO is kept as it is. When both pixel density are different from each other, the rotational speed of the polygon motor of the set pixel density is set (S3), whether the rotational speed is in the direction of acceleration or deceleration is judged (S4) and when it is in the direction of acceleration, the timing of /SYNCO is a little accelerated (S5). This is repeated to be the same as the timing of /SYNCO of the set pixel density (S6). When it is in the direction of deceleration, the timing of /SYNCO is a little decelerated (S7). |
