| 摘要 |
PURPOSE:To reduce crosstalk by setting the reflectance at the crystal part of a land and a groove within a specific range and setting the reflectance at the amorphous part at a specific value or less. CONSTITUTION:In the optical recording medium, information is recorded and erased at a groove and a land provided on a disc by irradiating the medium with a light beam and causing a change between amorphous phase and crystal phase. It is essential to set the reflectance in the range of 7-15% at the crystal part of the land and groove and at 5% or less at the amorphous part. When the reflectance at the crystal part is higher than 15%, the recording sensitivity decreases. When the reflectance at the crystal part is lower than 7%, the contrast of signal is deteriorated at the time of reproduction. When the reflectance at the amorphous part is higher than 5%, signal is read out easily from an adjacent track at the time at reproduction to increase crosstalk. |
