Record carrier having an optically readable information structure comprised of information areas of two different phase depths
AssigneeU.S. Philips Corporation
InventorJosephus J. M. Braat
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Abstract
A record carrier is described which has an optically readable information structure in which information areas of adjacent information track portions have different phase depths, and an apparatus for reading said record carrier. By a suitable choice of the phase depths and by an electronic phase shift of the signals supplied by the read detectors, cross-talk between adjacent tracks can substantially be eliminated.
Claims4
A record carrier having an information structure which comprises optically readable information areas arranged in generally parallel information tracks, adjacent information track portions differing from each other in that one of said adjacent track portions contains information areas of a first phase depth and the other of said adjacent portions contains information areas of a second phase depth which differs from the first phase depth by approximately .pi./2 radians.
Dependencies are inferred from the claim text.