| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent density unevenness of an image from generating in accordance with changes of a development condition and an environment condition while upsizing and cost increase of an apparatus are avoided. <P>SOLUTION: Among candidates of a plurality of conversion information (individual conversion information) used for converting a pixel gradation determined by an image processing means to an exposure, for each divided region of a photosensitive body surface, the suitable individual conversion information is selected according to the changes of the development condition and environmental condition. Conversion from the pixel gradation to the exposure (individual exposure conversion) is carried out individually for each divided region on the basis of the selected individual conversion information. The individual conversion information is information for making a potential after exposure agree with one reference potential at the time when the exposure obtained by converting one reference pixel gradation through the individual exposure conversion is applied to a nearly linear exposure characteristic except for a convergence region to a residual potential or an exposure characteristic which is the characteristic extended by extrapolation operation among exposure characteristics which show correspondences between the exposure in each divided region and the potential after exposure. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
