Disc-shaped recording medium, disc-state recording medium cutting apparatus, and disc drive apparatus

A cutting apparatus comprising:

• means for generating a series of predetermined signal units each composed of a signal part resulted from FSK modulation of information bit and a signal part of a single frequency;
• means for generating a drive signal on the basis of the signal supplied from the signal generating means;
• a laser source means;
• means for deflecting laser light from the laser source means on the basis of the drive signal from the drive signal generating means;
• and
• means for cutting a disc substrate by radiating the laser light to the disc substrate through the laser light deflecting means to form, on the disc substrate, a wobbled track including a series of predetermined units each composed of an FSK information bit part based on a waveform resulted from FSK imodulation of the information bit and a single-frequency part based on the waveform of the single frequency.

A disc drive for recording or reproducing data to or from a disc-shaped recording medium having preformed thereon a spiral, wobbled track as a groove or land along which data is to be recorded and in which the wobble of the track is a series of predetermined signal units each consisting of an FSK information bit part corresponding to a waveform resulted from FSK modulation of information bit and a single-frequency part corresponding to the waveform of a single frequency, the apparatus comprising:

• a head means for radiating laser light to a track to generate a return light signal;
• means for extracting a wobbling signal about wobbling of the track from the return light signal;
• and
• a wobbling information decoding means for making FSK demodulation of the wobbling signal to decode information represented by the information bit.