A method is used for adjusting a tilt of an optical pickup head. This extendibility may require several additions to the base software that is now operating as a web service program. The sleeve is movable in an axial direction between an opened and a closed position relative to the valve plug. This non-display period is provided by changing the electric potential of a storage capacitor line. On receiving the read request the selected server searches its database for messages having likeness to the auxiliary information of the request.