| 摘要 |
PURPOSE:To reduce uneven writing in a laser optical system device. using a plastic rotary polygon mirror. CONSTITUTION:As for the molding of the plastic rotary polygon mirror 18, it is difficult to stabilize its precision near the end parts along the rotating direction (a direction shown by an arrow C) of the mirror faces of the plastic rotary polygon mirror 18, so that the end parts are not used as effective reflection areas. Thus, laser beams are always reflected by the almost central part of the effective reflection area where high precision can be maintained, so that the uneven writing is reduced in the laser optical system device 10. |
