| 摘要 |
PROBLEM TO BE SOLVED: To prevent the bounding due to the vibration of a fold-over mirror and a casing by the simple constitution by providing a mirror reinforcing member extending in the longitudinal direction of a mirror and reinforcing the mirror on the rear surface of a mirror reflection surface for reflecting a scanning light beam deflected by a rotating polygon mirror. SOLUTION: This device is provided with a polygon mirror 2 as a rotating polygon mirror, a motor 4 rotatably driving the polygon mirror 2 in a constant acceleration manner and a mirror 8 for reflecting the scanning light beam 6 deflected by the polygon mirror and transmitted through an image forming element 5 to a photosensitive body 7 and the polygon mirror 1, the motor 4 and the mirror 8 are housed in a casing 9. A mirror reinforcing member 10 made of a glass material, extending in the longitudinal direction of the mirror 8 and reinforcing the mirror 8 is stuck to the rear surface of the reflection surface 8a of the planar mirror 8 being long in the scanning direction by means of an adhesive mirror dumping member. Consequently, the strength and volume of the mirror 8 are increased and vibration is prevented. |
