| 摘要 |
PURPOSE:To form an image with proper density even in a period wherein developer characteristics are different by varying image formation condition set according to the storage means of a storage means. CONSTITUTION:A control means 18 is connected to an environment sensor 19 and a potential sensor 20, and also connected to a memory 21 as the storage means and a varying means 22 which rewrites the contents of the memory 21. Then the storage means 21 is so constituted that its memory contents are held by, for example, a backup battery and a RAM or EPROM even when the means is powered off, and the contents of a certain area is added by colors as a superposition part at the time of contrast calculation. Further, the contents are rewritable at a proper time by the varying means 22 in service mode and then an optimum adjustment is made over a look at an image sample. The image formation condition which is thus set is varied by the varying means to form an image with invariably proper density even when the characteristics of a developer are remarkably different. |
