| 摘要 |
PURPOSE:To hold the potential of a photosensitive body at a specific value even if the photosensitive body changes in total use time and environment. CONSTITUTION:The potential controller is equipped with a surface potential detection sensor 15 which detects an inter-image potential on the photosensitive body 1, a comparative arithmetic circuit 21 which calculates the difference of its measured voltage from a target potential, a correction coefficient memory 23 where a correction coefficient corresponding to a halt time is set, a time counter 22 which counts the halt time, and a grid voltage arithmetic circuit 24 which calculates a voltage to the grid 12 of the electrostatic charger 2. Then the correction coefficient is corrected when the difference between the measured potential measured by the sensor and the target potential is larger than a certain value. |
