Patent ID: 7433277

Claim:
A wobble demodulator for reproducing digital information from an optical recording medium in which a track, for recording data in accordance with a wobble signal modulated so as to represent digital information by a combination of a modulation signal that is not frequency-modulated or phase-modulated and a carrier signal that is not frequency-modulated or phase-modulated, is wobbled to be formed, comprising: a wobble signal detector for detecting a wobble signal in accordance with wobbling of the track from the optical recording medium; a wobble PLL for detecting the carrier signal based on the wobble signal detected by the wobble signal detector; a wobble PLL lock determiner for detecting a lock state of a PLL representing a synchronization state in a frequency and a phase between the wobble signal and the carrier signal; and a decoder for reproducing address information by decoding the wobble signal detected by the wobble signal detector and the carrier signal detected by the wobble signal detector and the carrier signal detected by the wobble PLL in accordance with a detection result of the PLL lock determiner, wherein in the optical recording medium, the digital information is configured on a predetermined information block basis having a synchronization signal containing a predetermined sink pattern, data, and an error correction code of the data, the decoder is operated so as to detect and lock a synchronization position with respect to the digital information when the PLL lock determiner detects a PLL lock, and is operated so as to unlock the locked synchronization position when the PLL lock determiner detects a PLL unlock, the decoder includes an error corrector for correcting an error of the data based on the error correction code, and the decoder is operated so as to unlock a synchronization position when data reproduced in an information block in which a synchronization position is detected first is not error-correctable.