Magnetic recording disc having sector reference zone, device for reading same, and magnetooptical memory optoelectronic employing said device

摘要

A mode of writing on a magnetic recording carrier (DISC) where the information is distributed over a plurality N of tracks, each track being associated with at least one reference zone (ZRP.sub.ij) including preamble information, absolute address information and fine-position information. According to the invention, the mode of writing is characterized in that the reference zone includes a first portion (GCP. sub.ij) comprising preamble and address information and a second portion (GDP.sub.ij) comprising fine-position information, the first portion being disposed and centered over the track of serial number j, while the second portion is offset by one-half of a track with respect to the center of that track and on the same side of that track. The invention is applicable to magnetooptical disk memories.