| 摘要 |
PURPOSE:To obtain a uniform image extending over a long period of time, by providing a photodetecting means so as to detect a light beam from a part of a fluorescent lamp, which is nearest the middle point between the center part and the end part in the direction along the longitudinal direction of the fluorescent lamp, in an area where an original to be copied has been placed. CONSTITUTION:As for a rotation route of a photosensitive body 11, a charger 12 is provided in front of an exposure position 11', and the photosensitive body 11 is charged by operation of this charger 12. After that, the photosensitive body 11 is brought to exposure of an optical image of an original, by which an electrostatic latent image is formed on the photosensitive body 11, is developed 13 and is transferred 14. A light source 2 and an passive reflector 3 are held by a holding member 4, and an optical opening 4a is provided on this holding member 4. Also, a photodetecting element 5 is placed in the proximity of this optical opening 4a, or so as to tightly adhere to this opening, a part of a projecting light beam of the light source 2 passes through the opening 4a, is made incident to the photodetecting element 5, and the element 5 outputs an electric signal corresponding to the sensitive light quantity. |
