| 摘要 |
PROBLEM TO BE SOLVED: To prevent an illegal act such as the illegal copying of an audio CD from occurring. SOLUTION: When data are written in a data storage area (c), the data are modulated by using user specific information and stored in the data storage area (c) of an optical information record medium. When the data of the data storage area (c) are read, the data are demodulated by using the user specific information only when acquired user specific information coincide with the user specific information stored in a user specific information storage area (b). Thereby, only a user who have registered the user specific information and written the data can read the data in the data storage area (c). Since it becomes impossible for any third persons other than the user who have registered the user specific information to properly read the data in the data storage area (c), only the person who duplicated an audio CD can perform play back even when a recording medium such as an audio CD is duplicated, and thus the illegal act such as the illegal copying of the audio CD can be prevented from occurring. |
