| 摘要 |
PURPOSE:To reduce the load on a motor and high frequency core loss and to reduce the power consumption by making a voltage supplied to the motor lower in nonscanning mode than in scanning mode. CONSTITUTION:The device including a solid laser element 2 is heated up completely up to time t2 to complete scanning preparations and if a recording operation signal is not inputted to a motor power source 8 in T seconds from the time t2, the output voltage of the motor power source 8 is lowered to 18V from time t3=t2+T to time T4. When the voltage drops to 18V, the motor 4 can not generate enough torque to rotate a rotary polygon mirror 5 at a set rotational frequency R0 and the rotating frequency decreases to R1. This rotating frequency, however, is much larger than a bearing floating rotational frequency R2, so the supporting force for bearings is generated sufficiently and the bearings never contact each other. Consequently, the motor load is reduced and the high frequency core loss is decreased to reduce the power consumption. |
