| 摘要 |
PURPOSE:To calibrate a potential detector in a working condition and to permit quick calibration operation with high accuracy by making the selective application of voltages for calibration upon a photoreceptor possible. CONSTITUTION:In the stage of calibrating a potential detector 7, voltmeters 10, 16 are connected to respective measuring terminals 9, 15. Thereafter, the contact piece 13a of a calibration selection switch 13 is connected to a contact 13c side to apply the calibration voltage from a calibration voltage generator 14 to a photoreceptor 2. In this state, an amplifier 8 is regulated by operating a variable resistor 11 for calibrating said amplifier so that the voltmeter 10 indicates a reference value. Upon completion of the calibration, the contact piece 13a of the switch 13 is connected to a contact 13b side to ground the photoreceptor 2, and th voltmeters 10, 16 are removed. Since the potential detector is calibrated in a working condition, the calibration operation is performed in a short time with high accuracy. |
