| 摘要 |
PURPOSE:To prevent destruction and wear produced with a surrounding member due to shock and vibration by supplying a DC current to a coil of a moving part including an objective lens at the non-reproducing state to operate a holding force. CONSTITUTION:When a switch 9 is connected to a contact (a) at the reproducing state, a voltag from a power supply controlling circuit section 10 such as a DC- DC converter or the like is applied to an amplifier 13 adjusted by a feedback control signal 15, the moving part coil 14 including the objective lens is driven via the amplifier 13, thereby performing focus control of the objective lens. On the other hand, when the switch 9 is selected to a contact (b) at the non-reproducing state, a DC current via a resistor 16 is supplied to the coil 14 and the holding force is generated at the coil 14. Deformation, destruction or wear produced between the surrounding member and the moving member such as moving part coil including the objective lens due to shock and vibration is prevented at the non-reproduction by the operation of the holding force. |
