| 摘要 |
PROBLEM TO BE SOLVED: To control application of a charging voltage, by use of an appropriate charging voltage according to film thickness of a photoreceptor drum, regardless of changes in surrounding environment and secular change of the film thickness.SOLUTION: An image forming apparatus 1 includes: a film thickness detection section 102 which detects film thickness of a surface of a photoreceptor drum 21, on the basis of I-V characteristics indicated by a charging current in applying a plurality of different voltages; a temperature sensor 77 and a humidity sensor 78 for detecting ambient temperature and humidity of a charging device 22 and the photoreceptor drum 21; a film thickness correction section 104 which corrects the detected film thickness by use of a correction value determined according to the detected temperature and humidity; and a determination section 105 which determines a charging voltage corresponding to the corrected film thickness. An application bias control section 101 causes a charging-voltage application section 223 to apply the determined voltage as a charging voltage during image formation. |
