| 摘要 |
PURPOSE:To reduce the material cost to satisfy the standards for CDs by constituting a light reflecting layer of specified metals or alloys. CONSTITUTION:The light reflecting layer 4 is constituted of the metals or alloys having <=0.16 refractive index n and >=4.0 attenuation coefft. k in a 770 to 830nm wavelength range. Such metals include silver, copper and alloys essentially thereof; for example, Ag-Cu alloy, Au-Cu of >=20wt.% alloy, Ag-Au of <=50wt.% and Cu-Ni 1wt.% alloy. A disk 1 having the reflectivity higher than the reflectivity of the disk formed by using gold as the light reflecting layer is produced if these metals are formed as the light reflecting layer on a recording layer 3. The optical information recording medium 1 with which the reproduction signals satisfying the standards for CDs are obtainable is inexpensively formed in this way. |
