| 摘要 |
PURPOSE:To reduce the distance between a rotary polygon mirror and a photosensitive drum and to make the constitution compact by providing the photosensitive drum at the peripheral-surface directional position of the rotary polygon mirror and a laser beam source at a different horizontal height position from the photosensitive drum. CONSTITUTION:The laser beam source 1 is arranged above the polygon mirror 2 at the different horizontal height position from the photosensitive drum 4 provided at the peripheral-surface directional position of the polygon mirror 2. Further, the respective reflecting surfaces 2a of the polygon mirror 2 are slanted to the direction of the axis of rotation so that the laser beam from the laser beam source 1 is reflected toward the photosensitive drum 4. Therefore, the reflected laser light which is reflected by the polygon mirror 2 reaches the photosensitive drum 4 at any angle without being disturbed by the laser light source 1. Consequently, the distance between the polygon mirror 2 and photosensitive drum is reduced and the constitution is made compact. |
