METHOD FOR ADJUSTING DENSITY IN COPYING MACHINE AND DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a density adjusting method and a device capable of adjusting a copying machine so as to excellently perform the copying of a peculiar original having a large density difference between respective parts. ;SOLUTION: The density grade is reduced by lowering surface voltage of a photoreceptor by 100 volt (step S4). In this way, so called leading and trailing can be prevented. The density deficiency apt to occur by lowering the surface voltage, can be compensated by adjusting light quantity for illuminating the original to a value corresponding to the faint original (step S5). The fogging liable to be caused by reducing the light quantity, can be prevented by adjusting the developing bias (step S6). Moreover, the grade of the developing bias corresponding to the density value possible of being selected by the density adjusting key can be reduced (step S6). In this way, fine adjustment of the developing bias can be executed, by operating the density adjusting key. Therefore, the excellent copy corresponding to the peculiar original can be easily obtained.;COPYRIGHT: (C)1997,JPO