Patent ID: 8305852
Filing Date: 2012-11-06
Classification: G11B

Abstract:
1. An optical information recording medium comprising: a reflective layer formed on top of a circular substrate; a recording layer containing an organic dye formed on top of the reflective layer; and a light-transmissive layer formed on top of the recording layer; said optical information recording medium further comprising a burst cutting area provided on an inner side of the area where the recording layer is formed and a barcode-shaped mark is formed in the burst cutting area; said optical information recording medium being characterized in that a playback signal in the burst cutting area has a bright-area amplitude level that occurs when the location where no barcode-shaped mark is formed is played back, a dark-area amplitude level that occurs when the location where the barcode-shaped mark is formed is played back, and a maximum amplitude level constituted by a protruded waveform occurring when edges of the barcode-shaped mark are played back, and when a slice level is defined as a level equally distant from and set between the maximum amplitude level and dark-area amplitude level, the slice level is lower than the bright-area amplitude level so as to detect a location corresponding to the bright-area amplitude level where no barcode-shaped mark is formed.