| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus and a method of measuring the surface potential of a photosensitive layer with which the surface potential of a photosensitive layer provided on the surface of a photoreceptor can be measured with high accuracy.SOLUTION: A photoreceptor drum 31 includes a photosensitive layer. When a compound machine 1 is in a surface potential measurement mode, a DC voltage having a positive polarity is applied to a charging device 32 to measure a first discharge start voltage Vcs1 at which discharge to the photosensitive layer starts, and further a DC voltage having a negative polarity is applied to a transfer device 34 to measure a second discharge start voltage Vcs2 at which discharge from the charged photosensitive layer starts. A control unit 62 takes a voltage value obtained by adding the measured first discharge start voltage Vcs1 and second discharge start voltage Vcs2 as the measured surface potential. |
