Optical disc and optical disc apparatus

摘要

Physical addresses of the recording areas provided on an optical disc are represented in the first format that is time-axis data (wobbling groove) and the second format that is binary data (block header). The physical address value gradually increases from the inner most part toward the outermost part of this disc, while the first format and the second format remains in one-to-one correspondence over the entire recording areas. The distance the optical head must move to reach the target recording area can therefore be calculated easily, no matter where on the disc the optical head is located at present. This enables the optical head to make a fast access to the target recording area.