| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an image forming apparatus, preventing an exposure trace on the surface of a photoreceptor drum caused by an optical sensor from being left in a transfer image. <P>SOLUTION: A control part 115 controls an exposure device 111 to form a density detecting toner image on the photoreceptor drum 110, and the density detecting toner image is detected by the optical sensor 106. The optical sensor 106 applies LED light to the density detecting toner image, so that a surface potential difference between an irradiated part of the photoreceptor drum 110 and a non-irradiated part thereof is enlarged to leave the exposure trace. Then, the control part 115 causes a transfer power supply 114 to output a recovery bias voltage opposite in polarity to the normal transfer bias voltage in timing when the density detecting toner image passes a primary transfer roller 113. The recovery bias voltage applied to the primary transfer roller 113 recovers the surface potential of the irradiated part of the photoreceptor drum 110 in the direction of the primary charging. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
