| 摘要 |
PURPOSE:To correctly control the quantity of light outputted from a recording light source, by providing a dimming means which changes the output voltage supplied to the recording light source based on an output value converted from an analog value into a digital value. CONSTITUTION:By receiving an AC voltage of a level corresponding to control data for adjusting light from the output port 02 of a microcomputer 1, applying the AC voltage upon a diode bridge composed of diodes D1-D4 through an inverter INV and photo-coupler OPC, applying a DC voltage corresponding to control data for adjusting obtained as the rectified output of the diode bridge to a thyristor TR1 through RC smoothing circuits R3 and C, and controlling the arcing phase angle to the applied AC voltage, the electric power supplying time to a halogen lamp HL upon which the AC supply voltage is applied is controlled and the light emitting amount of the lamp HL is maintained at a prescribed value. |
