DISCRIMINATING METHOD AND DISCRIMINANT CIRCUIT FOR MAGNETO-OPTICAL RECORDING MEDIUM AND REPRODUCER USING THE METHOD AND THE CIRCUIT

摘要

PROBLEM TO BE SOLVED: To quickly discriminate the kind of a loaded magneto-optical recording medium. ;SOLUTION: A first magneto-optical signal is detected in a state that an alternate magnetic fieled is impressed on a magneto-optical recording medium and the medium is irradiated with a laser beam having a first intensity (S3, S4, S5) and when the first magneto-optical signal follows up the alternate magnetic field, the medium is discriminated as the magneto-optical recording medium of a second kind (S6, S7) and when the first signal does not follows up the alternate magnetic field, the medium is discriminated as the medium of a first or third kind (S6). Thereafter, a second magneto-optical signal is detected by irradiating the medium with laser beam having a second intensity in a state that the alternate magnetic field is impressed on the medium (S8, S9) and when the second magneto-optical signal follows up the alternate magnetic field, the medium is discriminated as the medium of a first kind (S10, S11) and when the second signal does not follow up the alternate magnetic field, the medium is discriminated as the medium of a third kind (S10, S12).;COPYRIGHT: (C)1999,JPO