OPTICAL HEAD FOR MAGNETO-OPTICAL RECORDING AND REPRODUCING DEVICE

PURPOSE:To perform the rewrite of information in one revolution of a magneto- optical disk, by providing optical systems for recording and reproduction and for erasure, and a permanent magnet for magnetic field formation, and arranging a convergence lens at a position confronting with the same track position of the magneto-optical disk. CONSTITUTION:The track of the disk 10 is radiated by a laser beam from a recording and reproducing semiconductor laser 2 by using a convergence lens 6 confronting by interposing the optical system 4 for recording and reproduction, the permanent magnet 8 for recording and reproducing magnetic field formation, and the magneto-optical disk 10. The upstream side of the track 10 is radiated via an erasing convergence lens 5 confronting with a similar semiconductor lens 2 for erasure, the optical system 3 for erasure, and the permanent magnet 7 for erasing magnetic field formation. And the erasure of the information in one revolution of the disk 10 and the recording of the information on the erased part of the track are performed, thereby, it is possible to perform the rewrite of the information rapidly in one revolution of the disk.