| 摘要 |
PURPOSE: To provide an optical recording medium having a high recording modulation rate in spite of a slight change rate in the film thickness before and after recording, has a large margin in the film thickness of film formation and is reloadable by detecting the change in the film thickness by irradiation of a recording layer with recording light as a phase difference. CONSTITUTION: The optical recording medium formed by laminating at least a dielectric layer, the recording layer 2 contg. a light absorber and a reflection layer 1 in this order on a transparent substrate 3 having guide grooves is irradiated with the recording light from the transparent substrate 3 side, by which the light is condensed onto the guide grooves of a groove width (r). The film thickness of the recording layer 2 is changed by the condensed light, by which the depth (d) of the groove parts is changed. As a result, the phase difference of the light arriving at the reflection layer 1 is generated before the photoirradiation and after the photoirradiation and the change in the reflected light quantity is read by this phase difference. Then, the optical recording medium having a high recording modulation rate in spite of a slight change rate in the film thickness before and after recording, has the large margin in the film thickness of film formation and is reloadable is obtd. |
