| 摘要 |
PROBLEM TO BE SOLVED: To perform image formation with a more inexpensive circuit constitution by controlling the rotation and phase control part of a scanner motor by generating an acceleration/deceleration signal by using a reference signal (BD sensor signal) in the horizontal scanning direction and to shorten the start-up time. SOLUTION: The device is equipped with a laser driving means, a motor driver which increases or decreases the rotating speed of the motor with the acceleration/ deceleration signal, a rotary polygon mirror which is rotated by the motor to reflect laser light, a sensor which receives light from the rotary polygon mirror and outputs the reference signal of the horizontal scanning direction a means of counting intervals of the signal, a 1st acceleration/deceleration signal generating means of generating the acceleration/deceleration signal according to the count value, a means of generating the reference signal to be outputted in set cycles, and a 2nd accelerating/deceleration signal generating means of detecting the difference (position) of the reference signal and sensor signal and generating the acceleration/decelerating signal according to the difference; and the acceleration and deceleration signals outputted from the 1st and 2nd acceleration/deceleration signal generating means are inputted to the motor driver to control the rotation of the scanner motor. |
