Process and device for regenerating the phase of synchronizing signals in a data carrier optical write-read apparatus

摘要

Process for the regeneration of synchronizing signals used for writing and/or reading recorded digital data or for recording on an optical data carrier, wherein the synchronizing signals are regenerated in phase by determining the phase shift of the center of specific pulses with respect to a clock signal. According to a preferred variant, the specific data and the useful information data are coded by a N.R.Z.-type code, the specific data being associated with pulse durations not used in the N.R.Z. code for recording information data. The specific data can be recorded in time multiplexing with digital information data or, according to a preferred variant, in the form of flags at regularly spaced locations on the tracks which define between them zones intended for the recording of data blocks. The recording of these flags can take place prior to any recording of digital information data in preetched form. The synchronizing signals regenerated on the basis of the reading of these flags can then also be used for writing during the information data recording phases.