| 摘要 |
A disk type optical recording medium that can limit the reproduction by a disk drive connected to a computer without drastically changing the specifications of recorded information on the medium conventionally processed by a dedicated player, thereby preventing illegal copying or the like. The disk type optical recording medium has information tracks formed by a pit train, and the information tracks have a read limiting region formed by a modified pit train including a special wobble or lateral displacement as modified from the pit train. In this read limiting region, the modified pit train can be followed by the tracking control of an optical pickup during low-speed rotation of the medium, thereby allowing proper reproduction. However, the modified pit train cannot be followed by the tracking control of the optical pickup during high-speed rotation of the medium, thereby disallowing the reproduction. <IMAGE>
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