| 摘要 |
PURPOSE:To obtain the magnetic recording medium having large playback S/N and possible for high-density recording, by providing the write-in layer having vertical magnetism anisotropy and high coercive force on the substrate and the readout layer having vertical magnetism anisotropy, low coercive force and large magnetic optical effect on this layer. CONSTITUTION:In the magnetic recording medium used for thermomagnetic recording and playback by means of laser beam, the magnetic thin film write-in layer 11 is formed with the alloy like Tb-Fe having vertical magnetic anisotropy and high coercive force on the substrate 10. Further, the read-in layer 12 is provided on the layer 11 with the alloy like Gd-Fe having low coercive force and vertical magnetic anisotropy, and the protective layer 13 is formed for the prevention of oxidation, allowing to form the recording medium. The He-Ne laser beam according to the information signal from the laser beam source 14 is irradiated to this medium from the layer 13, and the direction of magnetic field only at the part of Curie point or more is inverted with the magnetic field coil 20 to write in the information signal. Weaker laser light in read-in is delivered than at write-in, and the reflective light emitted from the layer 12 is detected with the detector 18 for the amount of revolutions of polarized surface and it is reproduced by the photoelectric converter 19. |
