| 摘要 |
PURPOSE:To appropriately control the surface potential of a whole picture area, to prevent occurrence of fogging or inverted fogging and to clearly record a picture by controlling each model potential formed on a photosensitive body by means of different exposure systems to target potential within a prescribed range. CONSTITUTION:When an electrostatic latent image is formed by means of two kinds of exposure devices 31 and 35 after a photosensitive body 1 is electrostatically charged uniformly, exposure quantities of the exposure devices 31 and 35 are controlled so that a 1st model potential VL1 obtained by the exposure of the 1st device 31 and a 2nd model potential VL3 obtained by the exposure of the 2nd device 35 can be set within a preset range. Therefore, even when developing bias potential calculated and set by the 1st model potential VL1 is used, characters, etc., by means of the 2nd exposure outputted by partially interrupting the 1st exposure can be outputted clearly without fogging like as the copied picture by the 1st exposure. Therefore, the surface potential of the whole picture area can be controlled appropriately and high-quality pictures which are free from fogging and inverted fogging can be formed. |
