| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetooptical recording medium for MSR (Magnetically induced Super Resolution) reproduction giving a high signal quality and using both faces of lands and grooves as recording tracks. SOLUTION: In the magnetooptical recording medium in which both land parts and groove parts on a substrate are used as recording and reproducing tracks by irradiating both parts with a laser beam via an objective lens, the ratio Wg/Wl of the track width (Wg) of the groove part and the track width (Wl) of the land part is >=0.65 and <=0.85. Further, the distance between grooves Gp is >=1.0×λ/NA and <=1.2×λ/NA, and the depth d of the grooves is >=λ/11n andηλ/8n, whereλstands for the wavelength of the laser beam, NA the numerical aperture of the objective lens and n the refractive index of the substrate.
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