| 摘要 |
PURPOSE:To easily set a copying area of any shape, by detecting the reproducing area of an original by a photosensor using plural color sensors. CONSTITUTION:An electrostatic latent image corresponding to an original 7 is formed on a photosensitive drum 18. A photosensor 20 for detecting the frame of the original 7 is placed under contact glass 2 so that it is moved together with a moving optical system for exposure, such as an exposure lamp 11, etc., and subscans the original 7. The photosensor 20 is constituted by arrying plural semiconductor color sensors CS1-CSn in the main scanning direction by the optical system for exposure of the original 7 installing them to a substrate 21, and also installing a slit member 22 which has formed a slit 22a corresponding to each position in order to raise the directivity of each color sensor CS1-CSn. On the other hand, an eraser of unnecessary latent image 24 for irradiating a light beam on the drum 18 for erasing is placed in the proximity of a position after exposure and before development of the drum 18. |
