OPTICAL DISK, OPTICAL DISK DEVICE, OPTICAL DISK RECORDING/REPRODUCING METHOD, AND INTEGRATED CIRCUIT

摘要

When a recording capacity of an optical disc is increased, the increased part of the addresses cannot be represented by the number of bits used for representing the address information of a conventional optical disc. Hence, an address format capable of representing the increased part of the addresses while being compatible with the conventional address format with the same number of bits is proposed. In an optical disc according to the present invention, a track on which data is recordable is divided into a plurality of blocks, and each block includes L pieces of sub blocks. On each sub block, M-bit first digital information specifying a block address of a block including the each sub block and N-bit second digital information capable of representing a numerical value equal to or larger than L are recorded. Where a value of the block address is smaller than a threshold value, the second digital information represents a value specifying a number pre-assigned to the each sub block; whereas where the value of the block address is equal to or larger than the threshold value, the second digital information represents a value other than the value specifying the number pre-assigned to the each sub block. Or, where the value of the block address is equal to or larger than the threshold value, the second digital information represents the value specifying the number pre-assigned to the each sub block; whereas where the value of the block address is smaller than the threshold value, the second digital information represents a value other than the value specifying the number pre-assigned to the each sub block.