| 摘要 |
PURPOSE:To achieve the improvement in quality by performing development bias voltage controlling concerning the latent images having been formed photoreceptor at the detecting of the ground density of the original and performing exposure controlling concerning with the subsequent latent images. CONSTITUTION:At the copying of the first sheet, the quantity of light obtainable in correspondence to the ground density of the original from said original is detected with a light quantity detector 8 and is transmitted to a voltage regulating member 11 by way of a control member 12. The voltage regulating member 11 applies a development bias voltage corresponding to the detected quantity of light to a developing part 4 perform bias voltage controlling of the latent images. At the copying of the second sheet, the detected quantity of light having been detected for copying the first sheet is transmitted to an exposure regulating member 9 via control member 12 and the exposure regulating member 9 regulates the optical path so that the exposure of the second and subsequent sheets becomes the detected quantity of light. On the other hand, the voltage regulating member 11 sets the development bias voltage adapted to the developing part 4 at a preset constant voltage, then the copying of the second and subsequent sheets forms superior images. |
