Flexure supported read head

Fluid bearing for axially movable head

Focal position detecting optical apparatus

Focus acquisition and maintenance for optical disk system

Focus control method and optical disc recording/reproducing...

Focus control system for optical read-out apparatus

Focus control through detection of the rate of error in discs wi

Focus detecting apparatus utilizing reflecting surface having va

Focus detection and control apparatus for maintaining accurate f

Focus error detection device for an optical recording/playing ba

Focus error detection device for an optical recording/playing ba

Focus initialization system for optical recording

Focus operation for an optical disk device

Focus operation for an optical disk device

Focus servo control device for optical disks having servo offset

Focus servo control system for automatically adjusting a relativ

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 loop correction