DISC-SHAPED RECORDING MEDIUM, DISC-STATE RECORDING MEDIUM CUTTING APPARATUS, AND DISC DRIVE APPARATUS

摘要

There is provided an optical disc having performed thereon a spiral wobbled
track as a grove and/or land along with data is to be recorded. The track is
wobbled
for a series of predetermined signal units each composed of an FSK information
bit
part based on a waveform resulted from FSK modulation of information bit and a

singe-frequency part based on a waveform of a single frequency. The FSK
modulation
uses two different frequencies of which the one is the same as the single
frequency and
the other is different from the single frequency. These different frequencies
are in
such a relation that each of them has an even number of wobbles and an odd
number
of wobbles alternately in a predetermined cycle.