| 摘要 |
PROBLEM TO BE SOLVED: To stabilize image quality in various image densities, so as to achieve a post-exposure potential of an image carrier, in consideration of variability of optical attenuation of the potential with respect to the exposure of the image carrier due to individual difference between machines in an early stage, secular change, and environmental change.SOLUTION: A charging bias and a developing bias are determined for achieving a target solid density. Exposure energy is determined so that a post-exposure potential of a photoreceptor 3 is equal to a residual potential. An optical sensor 102 detects image density change to be obtained when the exposure energy is changed in the determined charging bias and developing bias, to select exposure energy so as to achieve a predetermined image density change. The image density change has a correlation with the post-exposure potential of the photoreceptor 3, so that the post-exposure potential may be achieved. |
