| 摘要 |
PURPOSE:To increase reflectance and to improve durability by providing plural light-amplifying reflecting layers having different refractive indexes between a light absorbing layer and a light reflecting layer and forming the light reflecting layer with aluminum. CONSTITUTION:The reflection effect of an Al layer 5 is increased by inserting a layer having different refractive index between a light absorbing layer 2 and the light reflecting layer (Al layer) 5, especially by forming a titanium dioxide layer 3 having high refractive index on the light absorbing layer 2 and forming a silicon dioxide layer 4 having low refractive index in the side of the light reflecting layer 5. Moreover, since the light absorbing layer 2 and the light reflecting layer are not directly laminated, the durability of the disk is improved. Namely, if the light absorbing layer 2 and the light reflecting layer 5 are tightly adhered, the disk is deteriorated due to the changes with the lapse of time, however, both of the TiO2 film and the SiO2 film used in this optical disk are stable and shows no change with time nor deterioration. |
