| 摘要 |
PURPOSE:To obtain a preferable image with few density nonuniformity, by controlling the operational condition of a recording means corresponding to dispersion in a surface state on a recorder. CONSTITUTION:A surface potential fluctuates according to a place where a photosensitive drum 111 is located at the time of projecting a laser beam stably. The surface potential V of the photosensitive drum 111 at the time of projecting the laser beam is stabilized by applying potential control. In other words, by increasing/decreasing the driving current value of a laser diode 704 so as to correct the surface potential corresponding to the dispersion in the surface potential of each part on the photosensitive drum 111, a laser beam quantity is changed, then, the surface potential VL can be stabilized. To realize stabilization, the surface potential of the photosensitive drum 111 is measured, and the difference of a targeted value VL is found, and the laser beam quantity to be increased/decreased required for the correction of the difference is calculated, thereby, the optimum laser current value is decided. Furthermore, the laser current value is stored in a laser control circuit, and the value V of each point on the photosensitive drum 111 is covered to the targeted value VL by repeating the same control for several times. |
