Patent ID: 7869317
Filing Date: 2011-01-11
Classification: G11B

Abstract:
1. A multi-layer optical disc comprising m recording layers (m is an integer equal to or greater than three), each of the m recording layers including a test writing area and a data recording area, wherein the test writing area provided spirally in each of the m recording layers is divided into a first small area to an n-th small area (n is an integer equal to or greater than three), and wherein with respect to an unrecorded small area of a predetermined recording layer of the m recording layers, a combination of the recorded/unrecorded states of data in m−1 small areas at the same radius position of an other recording layer of the m recording layers differs from a combination of the recorded/unrecorded states of data in m−1 small areas at an other radius position of the other recording layer.