| 摘要 |
PURPOSE:To prevent the recording medium of a magnetized thin film from exerting an evil effect due to leaked magnetic flux on it by driving electromagnetically the optical element of an optical beam system and at the same time cutting off the leaked magnetic flux. CONSTITUTION:An object lens 2, etc. of the optical beam system of an optical pickup are driven electromagnetically by a driving coil 6, permanent magnet 8, etc. which are set within a housing 4. Thus the focus control, etc. are performed to a disk 1. A magnetic shielding member 13 is provided to the housing 4 to cut off the leaked magnetic flux. Thus an evil effect due to the leaked magnetic flux is prevented from exerting on the magnetized thin film of the disk 1. |
