OPTICAL DISK, METHOD FOR RECORDING AND REPRODUCING WRITE-ONCE INFORMATION ON AND FROM OPTICAL DISK, OPTICAL DISK REPRODUCING DEVICE, OPTICAL DISK RECORDING AND REPROUCING DEVICE, DEVICE FOR RECORDING WRITE-ONCE INFORMATION ON OPTICAL DISK, AND OPTICAL DISK RECORDING DEVICE

摘要

The present invention is a write-once optical disc having the information available to the copyright protection, such as protection of copyright protection using negative or software. Through the dielectric layer 212 on the disc substrate 211 to form the storage layer 213. Recording layer, an intermediate dielectric layer 214 on the (213), and sequentially laminating the reflective layer 215, to form an overcoat layer 216 on the back. A (one method of the write-once identification information) unit (220a), (220b) BCA in the disc circumferential direction of the storage layer 213 and a plurality of records. The BCA portions (220a), (220b) are recorded by lowering the vertical magnetic anisotropy. Reproduction, and detects the write-once type information by the differential signal.