Production of master recording media

Abstract

A CD master production system (1) has a pre-recording station (2) with a central robotic arm (6) for loading and unloading discs onto a succession of processing devices (19-24) including washing and resist application devices. An LBR station (3) performs laser recording on up to four substrate discs (D) at a time, mounted on spindles (41). There is real time recording head (51) height adjustment for focusing the recording beam to compensate for disc surface level variations. A sensing beam reflected from the disc is compared with a reference beam so that the phase difference indicates level variations. A post-recording station (4) performs post-recording operations, again with disc load/unload performed by a central rotating robotic arm (9). The recording station (4) is mechanically isolated from the pre and post-recording stations (2, 4).

Dependencies are inferred from the claim text.