| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus, capable of always forming appropriate images, regardless of the attenuation of the surface potential of a photoreceptor. <P>SOLUTION: Periodically, dark attenuation characteristics of the electric potential on the surface of a photoreceptor drum 20 are detected. Then, the target value -Vgt of a grid bias voltage -Vg of a charging unit 24, which is necessary for maintaining a charged electric potential -Vod of the developing position on the photoreceptor drum 20 at a set value -Vods, is detected from the detected dark attenuation characteristics. At image formation where a development unit 24 operates, the value of the grid bias voltage -Vg of the charging unit 24 is set to the detected target value -Vgt. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
