| 摘要 |
PURPOSE:To always execute uniform exposure by measuring the potential of respective parts exposed to reflected light from plural white patterns on a photosensitive body by a potential sensor. CONSTITUTION:The respective white patterns are respectively illuminated with light beams from auxiliary flash lamps 30a and 30b through a reflector and a reflection mirror, and the reflected light passes through a mirror, a lens and a mirror to be formed into an image on the photosensitive body 13, so that the electrostatic latent image of the white pattern is formed on the photosensitive body 13. The potential of the electrostatic latent image is measured by the potential sensors 26a and 26b, respectively. Respective output signals from the sensors are A/D converted by a potential control plate 45 and inputted in a CPU 46. In such a case, relation between voltage impressed on the lamps 30a and 30b from an auxiliary flash lamp power source 54 and the potential of the electrostatic latent image is the same as the relation between the impressed voltage on a flash lamp 7 and the potential of the electrostatic latent image of the white pattern, and the CPU 46 controls the impressed voltages on the main flash lamp 7 and the auxiliary flash lamps 30a and 30b. |
