| 摘要 |
PROBLEM TO BE SOLVED: To obtain an optical disk reproducing device and disk kind discriminat ing method capable of making decision as to whether CDs or DVDs by a method other than the number of peaks of focus error signals in order to effectively perform disk kind discrimination processing with a system using a pickup of a bifocal lens having two foci with the single lens and of being hardly affected by the fluctuation of laser power, reflection variation of the disk or the disper sion of regenerated signal modulation degree. SOLUTION: In detecting a tracking error by a phase difference method, limitations are added to the pulse trans of phase difference signals by a pulse width limiting circuit 35 within a tracking error detecting circuit 7 in such a manner that the pulses above the prescribed pulse width do not appear in these pulse trains. The kinds of the disks varying in the recording density, for example, whether the CDs or the DVDs are decided in accordance with the phase difference signals after the pulse width limitation or the phase difference signals before the pulse width limitation and after the pulse width limitation.
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