| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of accurately setting image forming conditions required for forming toner images of a relatively high target density and forming high quality images, and an image forming method. <P>SOLUTION: While changing and setting a DC development bias Vavg to be supplied to a development roller to biases Vavg<SB>-</SB>B and Vavg<SB>-</SB>C, the patch image of a density lower than a high density side target density D(op) is formed under each bias. The image density of each patch image is detected by a patch sensor. Then, a linear expression indicating the correlation of the DC development bias and the image density is obtained on the basis of the combination of the DC development bias and the image density. Then, on the basis of the correlation, the DC development bias Vevg<SB>-</SB>op corresponding to the high density side target density D(op) is obtained as an optimum development condition. <P>COPYRIGHT: (C)2003,JPO |
