| 摘要 |
PURPOSE:To expose light onto a photosensitive body at a correct position in the main scanning direction without being influenced by vibrations from a driving part even when the driving part is vibrating. CONSTITUTION:At the starting side of a drum 50 in the main scanning direction, a holder 91 is set and faced to the left end face of the drum 50 at a side plate 90 supporting a shaft of the drum 50. A sliding member 93 is attached to a holding member 92 to which a photodetecting element 80 is mounted. The sliding member 93 is made movable together with the holding member 92 within the holder 91. A pressurizing spring 94 installed between the side plate 90 and the holding member 92 inside the holder 91 presses the integral body of the photodetecting element 80, holding member 92 and sliding member 93 to the side face of the drum 50. The side face of the drum 50 is processed so that the sliding member 93 can smoothly slide. Accordingly, the photodetecting element 80 moves together with the drum 50 in the axial direction (main scanning direction) of the drum 50. |
