Patent ID: 7417926

Claim:
A detector for detecting information carried by a wobble signal having a sawtooth-like shape, the wobble signal having a base frequency of f wob , the detector comprising: a first band-pass filter, which has a center frequency close to 2*f wob , for receiving and filtering the wobble signal and generating a first filtered signal; a second band-pass filter, which has a center frequency close to f wob , for receiving and filtering the wobble signal and generating a second filtered signal; a first comparator for comparing the first filtered signal with a first reference voltage and generating a first compared signal; a second comparator for comparing the second filtered signal with a second reference voltage and generating a second compared signal; a delay unit for receiving the second compared signal, delaying the second compared signal by a preset time period, and then outputting a delayed signal; and a sampling unit for sampling the first compared signal using the delayed signal as a sampling clock, and outputting a sampled value representing the information carried by the wobble signal.