| 摘要 |
PURPOSE:To reduce the dimensional difference due to elongation and contraction between two surfaces of a recording medium and to prevent deformation of the medium by providing a transparent oxide film on a specified surface of a transparent resin substrate. CONSTITUTION:The one surface of a transparent resin substrate of an optical recording medium, where no recording layer is provided, is covered with a transparent oxide film comprising silicon oxide, magnesium oxide, boron oxide, barium oxide, aluminum oxide, or a mixture of two or more of these, having a refractive index n of 1.3<n<1.7. Thereby, both surfaces of the medium are almost in an equal state and the difference in dimension due to elongation or contraction can be reduced. Thus, deformation of the medium is prevented and the obtd. medium has high reliability. |
