| 摘要 |
<p>The present invention relates to an information medium including at least one face intended for recording, along tracks, optically readable information, the support being provided with pre-etching zones (5) alternating with zones (4) intended for recording the said information, the pre-etching zones containing discrete patterns embodying the mid-axis of the tracks. In each pre-etching zone, the discrete patterns consist of pits (23', 33') centred midway between two adjacent tracks and having an optical width, as furnished by a real optic with bounded transfer function, in the direction perpendicular to the axis of the tracks, substantially equal to the optical width of the zone situated between two successive pits in the said direction and in that, from one pre-etching zone to the next, the pits (23', 33') have equal offsets of opposite sign relative to the mid-axes of the tracks. The invention applies to digital optical disks. <IMAGE></p> |
