| 摘要 |
PURPOSE:To improve C/N by forming an underlying protective layer and protective layer of Y2O3 or Y2O3 type oxide and selecting the refractive indices of these protective layers at >=1.8. CONSTITUTION:This recording medium is formed by laminating and forming the underlying protective layer 11, a recording layer 12 and the protective layer 13 by sputtering in this order on a transparent substrate 10 consisting of low- grade polycarbonate. Such recording medium is formed to a disk shape and tracking grooves are formed on the recording surface thereof in the circumferential direction of the disk. More specifically, the protective layer 11 is formed on the substrate 10 and the magneto-optical recording layer 12 consisting of a material having a magneto-optical effect is provided via the protective layer 11 thereon. The protective layer 13 is formed on said layer. The protective layer 11 and the protective layer 13 are formed of Y2O3 or Y2O3 type oxide and are formed by selecting the same in such a manner that the refractive indices of the two layers 11, 13 attain >=1.8.
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