| 摘要 |
PROBLEM TO BE SOLVED: To make the time required for processing able to be shortened when an image is intermittently formed by making the start of a polygon mirror driving motor independent of the start of a photoreceptor drum driving motor. SOLUTION: When the photoreceptor drum is started to be rotated, the photoreceptor drum driving motor is driven when a throw-up signal being independent of the polygon mirror driving motor as a reference pulse signal. Thus, when the image is intermittently formed, only the photoreceptor drum driving motor can be intermittently driven and stopped while the polygon mirror driving motor is continuously driven. When phase difference between a scanning start signal and the throw-up signal becomes small to such an extent that the step out of the photorecetor drum driving motor can be evaded after the rotational frequency of the photoreceptor is stabilized (time T1), the driving of the photoreceptor drum driving motor is switched to the driving executed based on the scanning start signal from the driving executed based on the throw-up signal. |
