Semiconfocal optical disk readout with one linear-spread beam.
A novel, to our knowledge, optics pickup for semiconfocal optical disk is proposed. Five tracks are imaged simultaneously by use of one linear-shaped beam that extends over the tracks in the radial direction with the focusing and the tracking position controlled. We also show how the cross talk between tracks is eliminated automatically. The approximately diffraction-limited width of the beam and the small-signal detector elements make semiconfocal detection possible in the tangential direction.
Maeda
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Koyanagi
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