| 摘要 |
PURPOSE:To improve photographic reproducibility in a photographic mode by setting the device in a setting initial mode potential at the initial period of placement of the image forming mechanism main body and changing over to a photographic mode potential when a specified number of pieces is reached by the copied number of pieces. CONSTITUTION:In the photographic mode, the potential of the electrifying device is set to two stages of a photographic mode potential P1 of the main body and a lower setting initial mode potential P2, the setting initial mode potential P2 is taken at the initial period of placement of the image forming mechanism main body and when the specified number of pieces has been reached by the number of copied pieces by a counter 20 (for example, 2000 pieces), a photographic mode potential changeover means 21 is provided to output changeover signal to an electrifying device potential control means 18 so that it is changed over to the photographic mode potential P1. Therefore, since the developer is at the initial setting potential P2 which is slightly lower than the photographic mode potential P1 of the main body in the period of initial machine placement, an image with the good photographic reproducibility as the P mode, that is, a level where sufficient discrimination can be made from N mode is provided. |
