| 摘要 |
PURPOSE:To set the central value of the adjusting range of image exposure light quantity to the center of an adequate exposure of a drum, by installing an indicating member which indicates the characteristic of a photosensitive drum to the photosensitive drum and changing the central value of the adjusting range of image exposure light quality in accordance with the drum. CONSTITUTION:An AC voltage of a level corresponding to control data for dimming light is received from the output port 02 of a microcomputer 1, and impressed upon a diode bridge composed of diodes D1-D4 through an inverter INV and photocoupler OPC, supplying a DC voltage corresponding to control data for adjusting obtained as the regulated output of the diode bridge is supplied to a thyristor TR1 through RC smoothing circuits R3 and C, and by controlling the ignition phase angle to the impressed AC voltage, the electric power supplying time to a halogen lamp HL upon which the AC supply voltage is impressed is controlled and the light emitting quantity of the lamp HL is maintained at a prescribed value. |
