| 摘要 |
PURPOSE:To eliminate a bias magnetic field by applying a processing magnetizing the entire medium in a direction in advance. CONSTITUTION:A magnetic thin film of two-layer structure composed of a recording layer 3 and an auxiliary layer 2 is used as a magneto-optical recording medium. The Curie temperature of each layer is lower in the order of the auxiliary layer 2 and the recording layer 3, the auxiliary layer and the recording layer are made of perpendicular magnetization film and the perpendicular magnetic anisotropy is smaller in the order of the recording layer 3 and the auxiliary layer 2. The medium is magnetized uniformly in perpendicular direction to the film face in advance (the processing is called as the initial magnetization and the magnetized direction is referred to as positive direction as the convenience of explanation). Then when a light beam 5 irradiates a recording area to heat the corresponding part and to record the information, the light beam intensity is changed into two levels of strong/weak levels in response to the information signal. Thus, no bias magnetic field is required, the device is simplified, and the miniaturization of the device and the reduction of the weight are attained. |
