| 摘要 |
PURPOSE:To prevent an image from the unevenness of density and a developer from the generation of blocking by controlling the consumption of the developer so that the developer corresponding to the consumed quantity of the developer in an image area is consumed in a non-image area. CONSTITUTION:A laser beam corresponding to image information is radiated to an image area P corresponding to the size of a transfer material on a rotating photosensitive drum 1 to form a latent image. The quantity of toner consumed by the latent image in the image area is calculated by a control system based on the radiation time of laser beams and laser beams are radiated so that a latent image X having length l is formed in a subscanning direction to consume the same quantity of toner also in the non-image area in a main scanning direction. Thereby, toner T in a developing device 4 is uniformly consumed over the whole width independently of the size of the transfer material and is replaced by new toner at any time. Consequently, the electrified charge of toner is not locally increased by friction between the rotating developing sleeve 9 and the toner and a difference in the density of formed images is not generated. |
