Patent ID: 6031799
Filing Date: 2000-02-29
Classification: G11B

Abstract:
An apparatus for correcting tracking balance for use in an optical disc system which obtains a tracking error signal via differential phase detection, the tracking balance correction apparatus comprising:a pickup unit to detect a beam reflected from an optical disc and, in response, generating a high frequency reproduction signal and diagonal summing signals;a tracking balance correction unit to receive the diagonal summing signals output from said pickup unit, to adjust phases of the received diagonal summing signals, based upon a tracking balance correction voltage, to detect a differential phase, and to output the detected differential phase as the tracking error signal;an envelope detection unit to detect an envelope of the RF signal output from said pickup unit to output an envelope signal; anda digital signal processor to receive the tracking error signal from said tracking balance correction unit, generating a tracking drive voltage to set the tracking error signal to zero to thereby control tracking of said pickup unit, and at the same time generating the tracking balance correction voltage according to the maximum magnitude of the envelope signal from said envelope detection unit, and to then output the tracking balance correction voltage to said tracking balance correction unit.