| 摘要 |
PURPOSE:To set the surface potential of an image holding body at the optimum potential by transferring and outputting an developer image formed on the surface of the image holding body by bias potential with the same level of the surface potential as that of the image holding body on a material to be transferred, and adjusting an electrification inflow current to an electrification means corresponding to the image density of the developer image. CONSTITUTION:The bias potential to be impressed on the developing sleeve 12a of a developing device 12 is set at the surface potential with the same level as that of a photosensitive drum 10, and a halftone image formed on the surface of the photosensitive drum 10 is transferred on a sheet by the bias potential, and is outputted, and also, the electrification inflow current to an electrifier 11 for electrification is adjusted corresponding to the image density of the halftone image. In such a way, it is possible to perform adjustment corresponding to the performance of the photosensitive drum easily, and to adjust the surface potential of the photosensitive drum at the optimum potential with high accuracy. |
