Patent ID: 7577071

Claim:
A tilt amount detector for detecting tilt displacement of an optical pickup with respect to an optical disc, the tilt amount detector comprising: inputting means for inputting a reproduction signal supplied from an optical disc; a first filter portion for effecting correction of an optical transfer characteristic of the reproduction signal; a second filter portion for effecting correction of the optical transfer characteristic of the reproduction signal with a phase opposite to that of the correction effected by the first filter portion; reference clock extracting means for extracting a reference clock signal from the input reproduction signal; first jitter measuring means for measuring a jitter amount of each of an output signal from the first filter portion and the extracted reference clock signal and outputting the measured jitter amounts; second jitter measuring means for measuring a jitter amount of each of an output signal from the second filter portion and the extracted reference clock signal and outputting the measured jitter amounts; and difference calculating means for calculating a difference between the jitter amount measured by the first jitter measuring means and the jitter amount measured by the second jitter measuring means.