| 摘要 |
<p>A magneto-optical disk (23) has a recording layer (4) whereon recorded bits are formed by the magnetic field modulation method and a readout layer (3) whose axis of easy magnetization is parallel to the recording layer (4) at room temperature, and varies to be perpendicular to the recording layer (4) within a predetermined temperature range between room temperature and the Curie temperature. During reproduction of recorded bits a first semiconductor laser (10) emits a heating-use light beam (7) to form the first light spot on the readout layer (3). Thus, a ring-shaped region corresponding to the predetermined temperature range exhibits perpendicular magnetic anisotropy and the recorded bits are copied from the recording layer onto the ring-shaped region. As the first light spot is shifted, the ring-shaped region as a readout window of recorded bits is also shifted. Further, the second semiconductor laser (11) emits a reproduction-use light beam (8) such that the second light spot is formed on the readout layer (3) to overlap the first light spot at a rear portion thereof. Consequently, only one recorded bit copied onto the rear portion of the ring-shaped region can be reproduced. Therefore, high-quality reproduction signals can be obtained from the magneto-optical disk (23) inspite of information high density information recording. <IMAGE> <IMAGE></p> |
