| 摘要 |
PURPOSE:To prevent toner from being stuck to a copying sheet by holding a white-colored diffusion board in a position which interrupts a lighting optical path at the lower part of an original scanning direction edge reference position when the original exposure scanning is started, and retracting the white-colored diffusion board from the lighting optical path just after the original exposure scanning is started. CONSTITUTION:The white-colored diffusion board 60 is held in the position which interrupts the lighting optical path at the lower part of the scanning direction reference position P of the original 90 which is placed on an original plate glass 70 at least when the exposure of the original 90 is started. Consequently, light which projects the reference position P when the exposure is started is reflected on the white-colored diffusion board 60, and exposes an electrostatic latent image carrier. The white-colored diffusion board 60 is retracted from the illuminating optical path just after the original 90 exposure scanning is started, and an illuminated light is reflected on the edging part of the original 90 which is placed on the original platen glass 70, and the electrostatic latent image carrier is exposed. Thus the toner sticking to the edging part and to the inside part of the copying sheet is prevented. |
