Patent ID: 6345023
Filing Date: 2002-02-05
Classification: G11B

Abstract:
An optical disc apparatus for recording into or reproducing from an optical disc, on which a guide groove wobbling at a predetermined frequency is provided, comprising:a driver motor for rotating said optical disc; a signal extracting circuit for extracting a control information from said wobbling guide groove; a wobble detection circuit for extracting a wobble signal from the control information extracted by said signal extracting circuit; a driver motor controller circuit for controlling rotation number of said driver motor; and a clock oscillator circuit for outputting a clock for use of rotation control of said driver motor, wherein a frequency of said clock for use of rotation control is set at a frequency sufficiently different from the frequency of said wobble signal; and wherein said clock oscillator circuit is a pulse wave modulation oscillator, and the frequency of the clock for use of rotation control is set outside the frequencies in an area of wide capture fluctuation of the wobble signal.