Patent ID: 7957245

Claim:
A recording medium comprising: a first recording layer and a second recording layer, on each of which a track or tracks are placed spirally or concentrically, to record therein record information, wherein the first recording layer comprises a lead-in area to record therein control information for controlling at least one of recording and reproduction of the record information, the second recording layer comprises a lead-out area to record therein control information for controlling at least one of recording and reproduction of the record information, a distance between an inner radius of the lead-in area and an outer radius of the lead-out area is larger than or equal to a first predetermined value, said first recording layer comprises an identification area in which identification information for identifying said recording medium is recorded, and the first predetermined value is a value obtained by adding a tolerance length to 0.4 mm in a radial direction of said recording medium, in which the tolerance length indicates an acceptable range of a relative position shift between an address which is defined on a predetermined position in said first recording layer and an address which is related to the predetermined position in said second recording layer, wherein a distance between the inner radius of the lead-in area and an outer radius of the identification area is substantially equal to 186 μm, in a radial direction of said recording medium.