| 摘要 |
A control circuit (3) has: an angular velocity calculator (34) that calculates the angular velocity of a mirror on the basis of the angle of a mirror (11), said angle having been measured by angle measuring units (17b, 17c); a target angular velocity calculator (35) that calculates a target value of the angular velocity; a resonance frequency detector (33a) that detects the frequency of mirror vibration using the angular velocity and the target value; a drive waveform generator (31) that generates sawtooth drive signals; and unnecessary vibration controller (32), which optimizes the drive signals on the basis of the frequency detected by the resonance frequency detector such that the unnecessary vibration of the mirror is reduced, and which applies a voltage corresponding to the optimized drive signals to a piezoelectric element (152). The resonance frequency detector detects the frequency of the mirror vibration using the waveform and the target value of the angular velocity during a period when the sawtooth drive signals are transmitted from the drive waveform generator to the unnecessary vibration controller. |
