Patent ID: 8098566

Claim:
An optical disc, comprising tracks, each divided into a plurality of recording blocks; wherein: each of the plurality of blocks includes a run-in area and a data area; in the run-in area, a prescribed run-in bit pattern is recordable; in the data area, bit patterns having a plurality of bit lengths obtained by modulating data as a recording target in accordance with a prescribed modulation rule are recordable; at least one of spatial frequencies corresponding to the bit patterns having the plurality of bit lengths in accordance with the prescribed modulation rule is higher than a cutoff frequency; the cutoff frequency is defined as a frequency at which a gain of an optical transfer function (OTF) is 0 times; and the run-in bit pattern recordable in the run-in area includes the bit patterns having the plurality of bit lengths, from which the bit pattern corresponding to the frequency higher than the OTF cutoff frequency has been excluded, and wherein the run-in bit pattern includes the bit patterns having the plurality of bit lengths, from which the bit pattern corresponding to the frequency higher than the OTF cutoff frequency has been excluded, and which have a bit length equal to or shorter than a bit length at which a reproduction signal of the run-in bit pattern, obtained from reflected light when the optical disc is irradiated with a prescribed light beam, has a maximum signal amplitude.