Patent ID: 8023373

Claim:
A method of reducing power dissipation in a variable-gain photo-detector circuit ( 35 ) of a servo-tracking system, the variable-gain photo-detector circuit having an output to output a received main spot signal and at least one received side spot signal, the main spot signal and the side spot signal being formed by separating a light beam into a main beam and at least one side beam and focusing the main beam onto a main spot (M) and the at least one side beam onto a corresponding side spot (Si or S 2 ) on an optical record carrier, the method comprising: processing the received main spot signal with a first averaging circuit ( 1000 ) having a first cut-off frequency; and processing the received at least one side spot signal with a corresponding second averaging circuit ( 2000 ) having a second cut-off frequency, the second cut-off frequency being lower than the first cut-off frequency and based on control signal characteristics of the servo-tracking system.