| 摘要 |
PURPOSE:To provide an optical recording medium easy to produce and capable of high density recording and reproduction of information with high reliability as an optical recording medium with an RAM region in which information can be recorded and reproduced and an ROM region in which information is previously formed as geometric ruggedness and only reproduction is carried out and to provide recording and reproducing methods using the optical recording medium. CONSTITUTION:An RAM region is composed of a magneto-optical RAM region 10 and a phase change RAM region 11, an ROM region 12 is disposed between the regions 10, 11 and a reflecting layer common to the regions 10-12 is formed in the regions 10-12 without forming a recording film in the region 12. In relation to recording and reproduction in the RAM region, control information and retrieval information which are frequently rewritten are handled in the magneto-optical RAM region 10 and information which is not frequently rewritten is handled in the phase change RAM region 11. |
