| 摘要 |
PURPOSE:To make effective use of a wide rotating angle range by storing the data of the magnitude complying with the rotating angle of a scanning mirror by each time segment dividing in optionally equal parts with a rotating period and driving a scanning mirror according to the error between the data and the output of a rotary encoder. CONSTITUTION:A reference oscillator 32 generates clocks of a specified period, and an address counter 33 counts the clocks and generates an address for reading out data in an ROM34. The angle data read from the ROM34 is applied to a DA converter 35 by which the data is converted to an analog signal indicating a reference angle. A servocontrol amplifier 36 compares the signal indicating the rotating angle of a scanning mirror 2 from a rotary encoder 29 and the reference angle signal, inputs the output signal corresponding to the difference thereof to a driving coil 26 and controls the mirror 2 so as to make the error zero. The rotating angle range that can be effectively utilized for scanning is therefore widened. |
