Overwriting method and system for magneto-optical recording.

摘要

Modulating the intensity of directed energy for thermal writing of memory cells overwrites bits of either state in a storage layer of magnetic material irrespective of the preexisting condition of the cell without employing a magnetic field whose origin is external to the storage layer. Directed energy is synchronized with the medium by superimposing, preferably nonmagnetically, self-timing information on the medium itself and synchronously recovering the self-timing information to assist in directing energy to the medium. The medium itself has a magnetic layer plus recoverable timing information fixed in the medium along a predetermined path preferably embodied in a fixed periodic uniform variation in the nonmagnetic reflection properties along the track.