Mastering device, disc manufacturing method, disc-shaped recording medium, disc reproduction device, and disc reproduction method

A disk manufacturing method for manufacturing a disk-shaped recording medium by mastering in which first digital information is recorded by irradiating a laser beam onto a master disk to record a pit sequence and second digital information is further recorded by wobbling the pit sequence, wherein the mastering is performed by executing:

• a first signal generating step of generating a first signal by modulating the first digital information according to a required format;
• a bit selecting step of, according to a relative position from sync information contained in the first signal, allocating a plurality of bits constituting the second digital information in a unit period of the same sync signal;
• and
• a wobble modulating step of wobbling the pit sequence in both positive and negative directions according to an output of the bit selecting step.

A disk playback apparatus comprising:

• first reading means for obtaining a first signal that is recorded onto a disk-shaped recording medium with a length and pitch of pits by modulating first digital information according to a required format;
• second reading means for reading second digital information that is recorded so as to be superimposed on the first signal by wobbling the pits;
• a plurality of signal integrating means for integrating the second digital information read by the second reading means according to a relative position from a sync signal contained in the first signal read by the first reading means;
• and
• determining means for determining an output of the plurality of signal integrating means to decode a plurality of bits of the second digital information in a unit period of each sync signal serving as the second digital information.

A disk playback method comprising:

• a first reading step of obtaining a first signal that is recorded onto a disk-shaped recording medium with a length and pitch of pits by modulating first digital information according to a required format;
• a second reading step of reading second digital information that is recorded so as to be superimposed on the first signal by wobbling the pits;
• a plurality of signal integrating steps of integrating the second digital information read in the second reading step according to a relative position from a sync signal contained in the first signal read in the first reading step;
• and
• a determining step of determining an output of the plurality of signal integrating steps to decode a plurality of bits of the second digital information in a unit period of each sync signal serving as the second digital information.