| 摘要 |
PURPOSE:To produce a flawless void free of shadow and density unevenness, to simplify structure and to reduce its cost by providing a void producing part whose side at an optical system side is an upward reflecting plane with a fixed width and whose rear surface is white. CONSTITUTION:The void producing part 9 is composed of a reflecting member 10 and a white board 11. When an optical system 4 moves below an original leading edge 3a, light from a sub-reflecting mirror 7 irradiates the white plane 11a to generate reflected light for producing void on a slit side. At this time, a shadow area due to the lack of light quantity arises on the surface of an original in proportion to the height of the reflecting member 10, because the light from the sub-reflecting mirror is blocked by the white plane 11a. However, the shadow area is auxiliary irradiated with indirect irradiation light reflected from a main reflecting mirror 6 through an upward reflecting plane 10a, and is corrected. Thus, a clear, void image free of density unevenness can be produced. |
