An information recording medium for reproducing information by irradiation with a laser beam condensed by an objective lens with a numerical aperture NA includes a disk-shaped substrate and a recording layer disposed on the substrate. On the surface of the substrate, a plurality of prepit regions and a plurality of data regions are disposed alternately along spiral or concentric virtual track centers. Each prepit region includes a pair of wobble pits for tracking servo, and a length L (m) of the wobble pit along the virtual track center, a wavelength (m) of the laser beam, and a numerical aperture NA satisfy a relationship: 0.3L. NA/0.65.

 
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