Patent ID: 9087523
Filing Date: 2015-07-21
Classification: G11B

Abstract:
1. An information recording medium for optically storing data, which has a radial direction, comprising: a plurality of stacked data layers having layer numbers for identifying the data layers, each of the data layers having pre-format areas which are circumferentially divided into a plurality of segments having segment numbers for identifying the segments, the segments on one of the data layers being opposed to the segments on an adjacent one of the data layers, and the opposed segments having the same segment number, wherein management information including the layer number is recorded as a sequence of marks in at least one of the segments in each of the data layers, the marks are uniformly extended in a radial direction of the recording medium, and the sequences of marks on the adjacent ones of the data layers are separately allocated to the segments having the different segment numbers, which are not opposed to each other on the adjacent ones of the data layers; and at least one servo layer storing the layer numbers and the segment numbers relating to the layer numbers, the combination of the layer number and the corresponding segment number specifying the segment on which the sequence of marks are allocated.