Patent ID: 6088311
Filing Date: 2000-07-11
Classification: G11B,H03L,H04L

Abstract:
An optical disc device for reading data from and writing data to an optical disc using light, the device comprising:first selecting means for selecting, as input data, at least one of: header data recorded in a header area on an optical disc and channel data recorded in a data recording area between two adjacent header areas on the optical disc when said optical disc device processes at least one of the header area and the data recording area, and for selecting pseudo input data when said optical disc device processes a not-yet-recorded area between two adjacent header areas on the optical disc where no data is recorded;channel phase-locked loop means for generating a phase error signal representing a phase displacement between at least one of: the input data and the pseudo input data selected by said first selecting means and a feedback signal, for generating a frequency error signal representing a frequency displacement between at least one of: the input data and the pseudo input data selected by said first selecting means and the feedback signal, for increasing a sum of voltages of the phase and frequency error signals to generate a read clock signal having a frequency corresponding to the increased voltages for reading data from the optical disc, and for feeding back the read clock signal as the feedback signal for generating the phase and frequency error signals;wobble phase-locked loop means for generating a phase error signal representing a phase displacement between a wobble signal obtained from the optical disc and the feedback signal, for increasing a voltage of the phase error signal to generate a write clock signal having a frequency corresponding to the increased voltage for writing data to the optical disc, and for dividing a frequency of the write clock signal to generate and feed back the feedback signal having the same frequency as the wobble signal for generating the phase error signal; andfirst frequency dividing means for dividing the frequency of the write clock signal from said wobble phase-locked loop means by a number n to generate and furnish the pseudo input data to said first selecting means.