| 摘要 |
PROBLEM TO BE SOLVED: To execute multilevel recording on a recording layer at 5 stages or more by changing the irradiation power of a laser beam. SOLUTION: On the recording layer 12 of an optical recording medium 10, virtual recording cells 40 are continuously assumed in a group 16 along a track having a track pitch of 1 to 1.5 μm and, for each virtual recording cell 40, corresponding to information to be recorded, the irradiation power of a laser beam is modulated by 5 stages or more to form recording marks 48A to 48Q of 5 stages or more different in size and/or optical transmittance, and the optical reflectance of the entire virtual recording cells 40 including the outside of the recording marks is modulated at multiple stages to change the reflection level of the entire virtual recording cells 40 including the outside of the recording marks of a readout laser beam in reproducing is changed by 5 stages or more. |
