Patent ID: 8218414

Claim:
An information recording medium, wherein data is recorded on at least one of a plurality of recording layers by laser light incident on a surface of the information recording medium, wherein: the plurality of recording layers include a first recording layer, and second through N-th recording layers (N is an integer of 3 or greater) which are sequentially located in a direction from the first recording layer toward the surface on which the laser is incident; each of the plurality of recording layers has a first calibration area and a second calibration area located outer to the first calibration area; the first calibration area located in each of the first through N-th recording layers is located at a different radial position from a radial position of the first calibration area in each of the other recording layers; and the second calibration area located in each of the first through N-th recording layers is located at the same radial position as a radial position of the second calibration area in each of the other recording layers.