| 摘要 |
PURPOSE:To realize a deflection scanning device without generating vibration due to difference in thermal expansion when temperature is raised during a high speed rotation and without deforming a reflection surface in a rotary polygonal mirror. CONSTITUTION:A shaft 1 is inserted freely into the center hole of the rotary polygonal mirror 5, and the rotary polygonal mirror 5 is supported with a flange 4 integrated with the shaft 1 and fixed to the flange 4 with screws 6a-6d penetrating through holes 5a-5d (holes 5a, 5c are not shown). The shaft 1, the flange 4, the rotary polygonal mirror 5 and the screws 6a-6d are made of the same material, and respective rates of linear expansion are equal. Then, evn when temperature is raised due to heat generation in a motor during a high speed rotation, occurence of vibration and deformation in the reflection surface due to the deformation in the rotary polygon mirror 5 by increasing remarkably compressing force of the screws 6a-6d are prevented. |
