| 摘要 |
PURPOSE:To form always high-quality images by detecting an extent of dark decay in a photosensitive body after the lapse of a prescribed time length from electric charging and controlling the surface potential at the developing position of the photosensitive body in accordance with the obtained value. CONSTITUTION:The photosensitive body(drum) 1 is charged to the prescribed potential, and after the lapse of a prescribed time length the surface potential of the drum 1 is detected by a surface potential sensor S. The obtained extent of the dark delay is equal to the extent of the dark decay at the developing position in an image-forming process which is obtained by setting the prescribed time length to the value obtained by calculating the distance between the position of detecting the surface potential and the developing position and processing speed, thus permitting the surface potential of the drum 1 at the developing position to be maintained always at a constant value, irrespective of change of dark decay due to the kind of the photosensitive body and use for a long time, dispersion at time of manufacture, a number of developing devices, and developing processes, by controlling the surface potential of the body 1 at the developing position on the basis of the calculated value. |
