| 摘要 |
PURPOSE:To facilitate visual diagnosis of the operation state of the image forming device and to share the information by recording the diagnostic result in an outside image recorder/reproducer. CONSTITUTION:A developing bias electric power source 15 is controlled through a D/A converter 16 by CPU 13, and voltage varied in steps is impressed to a photosensitive body 1 through a conductive brush 9. Surface potential of the photosensitive body 1 is detected by a potential sensor 8, output of the potential sensor 8 is read by the CPU 13 through an amplifier 11 and the A/D converter 12. Video signals to display a graph corresponding to the output of the potential sensor 8 is generated by the video signal generating circuit 22, and the graph showing variation of output of the potential sensor 8 is displayed on CRT display 23. |
