| 摘要 |
PURPOSE:To reduce the time required for rewrite by using a light spot by a preceding optical head so as to erase recording information, recording the information by the preceding light spot in a couple of light spots by the succeeding optical head and reading the recording information by the succeeding light spot. CONSTITUTION:Erasure is applied by arranging uniformly the direction of magnetization of the perpendicular magnetized film through the cooperation between the erasure light spot 7 preceding the recording track and the magnetic field by the N pole of a magnetic field provision means 8 at rewrite and the information is recorded onto the track after erasure succeedingly by the cooperation of the recording light spot 4 and the magnetic field of the S pole of the magnetic field provision means 8. Erasure is applied in advance by the preceding erasure light spot 7 in this way and the recording is applied succeedingly to apply two operations of erasure and recording nearly in parallel. Thus, the time required for rewrite is reduced. |
