| 摘要 |
PURPOSE:To realize compact in design and to reduce the function of a leakage magnetic field to a photomagnetic disk for the titled controller, by driving an objective lens in both vertical and horizontal axial direction without giving a tilt to the optical axis. CONSTITUTION:When a tracking control current is flowed to a tracking drive coil 17, a magnetic field is generated to the coil 17. Then the coil 17, a lens barrel 10, an objective lens 4 and a counter balance 18 are displaced in the disk radius direction by an interaction of the magnetic field of the coil 17 and the magnetic field generated by a tracking permanent magnet 13. A focus control current is flowed to a focus driving coil 23 to produce a magnetic field. Then a tracking controller supported by an intermediate supporter 11 is displaced in the focus direction by an interaction of the magnetic field of the coil 23 and the magnetic field produced by a focusing permanent magnet 19. Many contrivances are applied to prevent the effect of a leakage magnetic field to a recording medium 8' of a photomagnetic disk. |
