| 摘要 |
PURPOSE: To attain high density recording by an optical modulation recording system. CONSTITUTION: A recording/erasing optical head 15 and a reproduction exclusive optical head 22 are provided in a magneto-optical disk device 10. A laser of a usual wavelength λ=680nm is used for the recording/erasing optical head 15, and the laser of a short wavelength, an SHG(second harmonics generation) green laser 23 of the wavelength λ=532nm, in this example, is used for the optical head 22. Then, a recording pit smaller than an outside diameter of a laser spot of the wavelength λ=680nm is formed at a recording time. Further, since the laser spot of the wavelength λ=532nm smaller than the intervals of the recording pits is formed at a reproducing time, the recording pit is surely read. |
