Patent ID: 7420899
Filing Date: 2008-09-02
Classification: G11B

Abstract:
1. A multi-layered information recording medium, comprising: a plurality of recording layers; a user data area for recording user data, provided in at least two of the plurality of recording layers; and a defect list storing area for storing a defect list that is information for managing a defective area detected in the user data area, wherein the defect list storing area is provided in a prescribed layer of the plurality of recording layers, the defect list is information for managing a defective area detected in the prescribed layer and a defective area detected in a recording layer other than the prescribed layer, at least one of the plurality of recording layers other than the prescribed layer comprises a spare defect list storing area that is used to record the defect list when the defect list storing area is not usable, the defect list includes a header, and the header includes a identifier for identifying the defect list, update count information indicating the number of repetitions of rewriting the defect list, and a number of defect entries information indicating the number of defect entries.