| 摘要 |
PROBLEM TO BE SOLVED: To provide a demodulation circuit capable of appropriately performing the detection of a phase deviation and the correction of the deviation and accurately performing demodulation. SOLUTION: This circuit is provided with a carrier wave generation circuit 18 for detecting the carrier waves of wobbling signals obtained from a medium and a phase adjustment circuit 24 for generating phase comparison signals provided with the phase difference of 90 deg. with the output signals of the carrier wave generation circuit 18 and capable of finely adjusting a phase. By detecting the phase difference based on the multiplied result by a multiplier 20 of the phase comparison signals and the wobbling signals, even in the case that a difference is generated in the delay amount of a carrier wave detection system and a wobbling signal detection system such as the case that a frequency is changed, the phase deviation of the carrier waves and the wobbling signals is detected. |
