| 摘要 |
PURPOSE: To form a 2nd toner image without occurrence of any defect such as uneven density even when uneven charging of a photoreceptor drum takes place due to soiling onto a 2nd charging device by toner by making the resolution of a 2nd image exposure means lower than that of a 1st image exposure means. CONSTITUTION: A 2nd charger 14 is used to change uniformly the surface of an image carrier 10 on which a 1st toner image is formed and a 2nd laser scanner subjected to stimulation control corresponding to a 2nd image signal emits a 2nd image exposure light 15 to the surface of the image carrier 10 to form a 2nd electrostatic latent image on the surface. Then the electrostatic latent image is developed by a 2nd development device 16 to form a 2nd toner image on the surface of the image carrier 10. The 1st and 2nd image signals are multi-valued digital image signals 0-225 proportional to the image density desired for output, and the resolution of the former is 400dpi and that of the latter is 200dpi. Since the resolution of the 2nd image exposure means 15 is small, even when uneven charging due to soiling of toner takes place in the device 14, the 2nd toner image is formed without causing the defect of uneven density. |
