| 摘要 |
PURPOSE:To make possible recording and erasing simultaneously by irradiating two light beams onto a recording medium while giving magnetic field of one direction to the recording medium by an electromagnet and making recording of information by modulated light beam and making erasing of information by unmodulated light beam. CONSTITUTION:As shown in the figure (a), in adjoining track C and track D of a recording medium 1, the track C is magnetized upward and erased as initial state, while information of '1' and '0' is recorded in the track D. In the figure (b), downward magnetic field is given to the recording medium by an electromagnet 7, a laser driver 25 is driven to modulate a light beam A and the light beam A is irradiated onto the track C, and at the same time, a light beam B is irradiated onto the track D without modulation. Then, information is recorded successively in the track C by the light beam A, and information is erased successively in the track D by the light beam B. As shown in the figure (c), information is recorded in the track C and information in the track D is erased.
|
