Patent ID: 7903505

Claim:
An optical disc, in which a track on which data is recordable is divided into a plurality of blocks, and each block includes L pieces of sub blocks, wherein: 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, wherein: where the value of the block address is smaller than the threshold value, the first digital information represents a value specifying the block address; whereas where the value of the block address is equal to or larger than the threshold value, the first digital information represents the value specifying the sub block number pre-assigned to the each sub block and a value specifying a part of the block address of the block including the each sub block; or where the value of the block address is equal to or larger than the threshold value, the first digital information represents the value specifying the block address; whereas where the value of the block address is smaller than the threshold value, the first digital information represents the value specifying the sub block number assigned to the each sub block and a value specifying a part of the block address of the block including the each sub block.