A central servo control system is used in an optical disc drive to control an optical pickup head. The optical at least includes a lens. The central servo control system includes a radio frequency (RF) amplifier, a sled motor, a tracking coil, and a central servo controller. The RF amplifier chip is coupled to the optical pickup head so as to receive the optical signal, which is amplified and processed so as to produce a RF data signal, a tracking error (Te) signal, and a central servo (Tcs) signal. The sled motor is used to hold the optical pickup head and move the optical pickup head to a desired position. The tracking coil located on the optical pickup head is used to move the lens to a designed position so as to allow the optical signal to be easily detected by the optical pickup head. The central servo controller receives the RF data signal, the Te signal, and the Tcs signal from the RF amplifier chip, and accordingly exports a tracking control signal to the tracking coil. If the system is operated at a following mode, the central servo controller exports the tracking control signal to control the tracking coil according to the Te signal. If the system is operated at a seeking mode, the central servo controller exports the tracking control signal to control the tracking coil according to the Tcs signal.

An apparatus (C) manufactures an information record medium (DK), which has a track (G, L), on which information is optically recorded. The apparatus is provided with: a track forming device (40, 43, 50) for forming the track; and a transition portion forming device (40, 43, 50) for forming a transition portion (MG) for transiting an irradiation position (SP) of a light beam (L.sub.G, L.sub.L), which is used for illegally copying the information on the formed track, from an irradiation track (G2), which is irradiated by the light beam, to an adjacent track (G1), which is adjacent to the irradiation track and on which the information is recorded before the information is recorded on the irradiation track, such that the formed transition portion is continuous with the formed track.

A stamper and optical disk. A photoresist is applied to a substrate and this photoresist is exposed, developed and then transferred to form a disk master which has a recess/protrusion pattern formed on its one side. The one side of the disk master is etched to narrow the width of a protruding part constituting the recess/protrusion pattern, and the recess/protrusion pattern of the disk master with the reduced width of the protruding part is transferred to form a stamper. The recess/protrusion pattern provided on the stamper is transferred to form a predetermined pattern on a substrate of an optical disk.

An optical recording medium according to the present invention includes a data recording area forming a double spiral structured track having spiral recording tracks each formed of a groove and a land adjacent to the groove, and a reproduction only area forming a single spiral structured track consisting of a pit row.

An optical storage unit which uses a light beam to record information on and/or reproduce information from a recording medium. The recording medium is provided with at least one land and at least one groove, and information is recorded in plural sectors in each of the land(s) and groove(s). The optical storage unit includes an optical phase adjuster for adjusting a phase of a polarization component of the light beam reflected from the recording medium based on a track type determination of a target address. An optical pickup is provided for reproducing information recorded on the recording medium using the phase-adjusted polarization component of the light beam.