摘要 |
A high density optical storage system employing a laser beam for reading data in a track on a rotating optical disk containing a large number of closely spaced concentric tracks. When a short seek operation is to be provided, track following is temporarily suspended for an appropriate time period during which specially shaped waveform is applied to the galvanometer-controlled mirror in the path of the beam. This specially shaped waveform is a doublet comprising a pulse of one polarity followed by a pulse of the opposite polarity. The duration and amplitude of these opposite polarity pulses are chosen based on the number of tracks that the beam is to be moved and the mechanical characteristics of the system so that the galvanometer mirror will accurately move the beam the requested number of tracks. After movement of the beam has been completed, operation automatically returns to track following.
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