Optical disk, an optical barcode forming method, an optical disk reproduction apparatus, a marking forming apparatus, a method of forming a laser marking on an optical disk, and a method of manufacturing an optical disk

摘要

Data is recorded on an optical disk. In a prescribed region of the disk, an identifier is provided for indicating whether a barcode-like mark is present or not on the disk. The identifier and the barcode-mark are in different locations on the disk. At least a portion of the barcode-like mark overwrites a pre-pit area of the disk.