| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical recording medium with which multi-level recording of five or more levels can be perform on a recording layer by changing the irradiation time of a laser beam. SOLUTION: Virtual recording cells 40 are assumed in grooves 16 on the recording layer 12 of an optical recording medium 10. The irradiation time of a laser beam is modulated at five or more levels every virtual recording cells 40 in accordance with information to be recorded. Recording marks 48A to 48G having different sizes of five or more levels are formed, light reflectances on the virtual recording cells 40 are modulated at multilevels, thereby changes the reflecting levels of a read laser beam during reproduction at five or more levels. |
