摘要 |
A mirror driving apparatus includes a rotary mirror, a support member for rotatably supporting the rotary mirror, a driving section for rotating the rotary mirror, a rotary electrode mounted on the rotary mirror or the support member, a fixed electrode disposed close to the rotary electrode and generally parallel thereto, a fixing section to which the support member and the fixed electrode are mounted, and a detecting section for detecting electrostatic capacity or a variation thereof between the rotary electrode and the fixed electrode. A mechanical vibration system, formed by the rotary mirror and the rotary mirror support member, is controlled based on the amount of rotary movement of the rotary mirror detecting as a change in capacity between the electrodes to suppress resonance of the rotary mirror. Additionally, by superposing an additional high frequency component outside the control band onto the rotary mirror control signal, the rotary mirror can be moved in fine increments. Thus, a dead band region (hysteresis characteristic) of the mechanical vibration system is limited.
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