| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which is capable of reducing developer deterioration without generating fogging and image defects, and suppressing decrease in image density and image quality. <P>SOLUTION: An image forming apparatus is characterized in comprising: a photosensitive drum having an electrostatic latent image formed thereon; a developing sleeve which develops the electrostatic latent image as a toner image; a printer control part which changes a rotation speed of the developing sleeve; a CPU which detects a maximum image density formed on a sheet among a prescribed number of sheets; an image processing unit which controls to execute a first mode for forming an image at a first rotation speed of the developer sleeve when the maximum image density detected by the CPU is a prescribed value or greater, and execute a second mode for forming an image at a second rotation speed lower than the first rotation speed of the developer sleeve when the maximum image density detected by the CPU is the prescribed value or lower; and a first and a second lookup table for determining an image density gradation property according to the first and the second mode. <P>COPYRIGHT: (C)2013,JPO&INPIT |
