| 摘要 |
PROBLEM TO BE SOLVED: To form a high quality image in which exposure hysteresis phenomenum is reduced with a normal amount of discharge exposure. SOLUTION: Based on the surface potential of a photoreceptor 1 measured by a potential sensor 9, a surface potential decrease due to exposure hysteresis is judged for every specific gradation area, and an exposure hysteresis erasure circuit 16 prepares an exposure hysteresis erasure profile corresponding to each gradation area and stores it into a memory 17. Further, based on image signals, which correspond to one round of the photoreceptor 1, and the exposure hysteresis erasure profile, the exposure hystersis erasure circuit 16 producer an exposure hysteresis erasure filter corresponding to each of the image elements of the image signals corresponding to the one round of the photoreceptor 1 and stores it into the memory 17. Further, based on the exposure hysteresis erasure filter used in latent image formation one round before of the photoreceptor 1, the exposure hysteresis erasure circuit 16 controls an amount of image exposure for latent image formation for the next round. |
