| 摘要 |
PURPOSE:To form stable images without any effect of fluctuations of charging conditions by controlling the staircase form applied voltage, developing bias voltage, etc. corresponding to the electrostatic contrast functions to a corona discharger according to the detection of electrostatic latent image potentials. CONSTITUTION:Discharging of polarity opposite from that of a discharger 2 by a secondary corona discharger 3 which is evenly charged by the primary corona discharger 2 and whose back face is optically open and the radiation of image light cause latent images to be formed on a photosensitive drum 1. The potentials of the bright and dark parts of the latent images are detected with a potential detecting probe 6 and are applied via A/D converter 14 to a control part 15 to which the signal corresponding to the turning position of the drum 1 by a drum rotation pulse generator 12 is applied. The control part 15 controls the staircase form applied voltage, bias voltage for developing device 7, etc. corresponding to the contrast functions by way of D/A converters 16 thru 18, control voltage sources 19 thru 21, etc. Hence, the good images of good contrast free from fog, etc. are formed without the effect of ambient conditions such as temperature, etc. |
