| 摘要 |
<p>There are provided an optical disk and a manufacturing method thereof which can increase its recording capacity, e.g. to 15 GB or higher. This optical disk may comprises an optical disk substrate 3 in which successive pits corresponding to a recording signal are formed, a reflection film 4 formed in this optical disk substrate 3 on its surface that successive pits 2 are formed and a light transmissive layer 5 formed on this reflection film 4. When a recorded signal is read out, i.e. reproduced from the optical disk, a signal recorded as successive pits is read out by irradiating of short-wavelength laser light having a wavelength of 350 nm to 420 nm from the side of the light transmissive layer 5 formed on the surface of the optical disk. Moreover, in this optical disk, when the successive pits are observed from the side of the light transmissive layer irradiated by reproducing laser light, the successive pits contain pits having length and width ranging from 80 nm to 250 nm, and the reflection film has the film thickness selected to be 20 nm or less, e.g. greater than 8 nm. <IMAGE></p> |
