| 摘要 |
PURPOSE:To attain the stable control of the rotational vibrations of a mirror by deforming previously a leaf spring supporting the mirror into a form of a vibration mode of a secondary or more degrees. CONSTITUTION:Each of two leaf springs 47 and 49 is deformed into a form of a secondary deformation mode and fixed to a fixing stage 46 at one of both ends with the other end fixed to a holder 42 respectively. When a drive coil 44 is energized, the torque is produced by an electromagnetic driving mechanism 45 and a mirror 41 is revolved attending on the deformation of both springs 47 and 49 which are caused in a secondary vibration mode. In such a rotary mirror device 40, the resonance peak of the primary mode is secured at about 90Hz and no peak emerges in any area of a frequency higher than 90Hz. Thus a control hand area is increased without deteriorating the stability when the device 40 is used as a tracking actuator of an optical disk device. The same effect is also ensured with the deformation into the vibration modes of a secondary or more degrees. |
