| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of stably forming a high-resolution image by restraining the fluctuation of the density of the high-resolution image to be formed in a high resolution mode. <P>SOLUTION: In the image forming apparatus, a patch pattern 309 for expressing density reference is formed on an intermediate transfer belt 22 in accordance with contrast potential (image forming condition) set for the high resolution mode at present, the density of the patch pattern 309 formed on the belt 22 is detected, and the contrast potential Vcont is changed and set to the contrast potential Vcont applied to the high resolution mode in accordance with the detected density. Based on the contrast potential Vcont, the output voltage of each of high-voltage power sources 301 and 302 supplying grid bias and a high-voltage power source 303 supplying developing bias is controlled, so that the image density is controlled. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
