摘要 |
PURPOSE:To prevent a copied image from the deterioration in quality by arranging a slit member between the 1st and 2nd mirrors to prevent a photosensitive body from being irradiated by unnecessary light at the time of scanning. CONSTITUTION:The 1st and 2nd mirrors 1, 2 constituting a scanning optical system are fixed on a supporting stand 10 so as to be crossed at right angles and the supporting stand 10 is moved in the arrow direction at a half speed of the photosensitive body 4 to scan the photosensitive body 4. A slit member 11 having a slit-like opening is fixed on the supporting stand 10. When the mirrors 1, 2 and the slit member 11 are unitedly moved, effective light flux projected to a slit exposure part of the photosensitive body 4 always passes the opening 12 of the slit member 11 without partial interruption, but unnecessary light (harmful light) other than the effective picture light flux is interruped by the slit member 11. |