Focus servo control system for automatically adjusting a relativ

Focus servo controller with collision avoidance and method...

Focus servo controlling apparatus, information reproducing...

Focus servo controlling method and apparatus

Focus servo controlling method and apparatus and optical...

Focus servo device

Focus servo device for detecting and compensating for disk abnor

Focus servo device for use in an optical information read-out de

Focus servo device of a system for reading out recorded informat

Focus servo gain setting circuit for optical record disc reprodu

Focus servo loop correction

Focus servo loop off-set compensation

Focus servo pull-in apparatus for use in a compatible disk playe

Focus servo recovery processing method for optical disc...

Focus servo system having object lens protection circuit for an

Focus-balance calibration method

Focus-balance calibration method

Focus-servo correction utilizing storage of detected focus error

Focus/tracking actuator with moving-magnet motors

Focus/tracking servo automatic gain control for optical recordin