PRODUCTION OF MAGNETO-OPTICAL RECORDING MEDIUM

PURPOSE: To stably suppress signal crosstalks at a low level by forming films by controlling either or both of the thicknesses and refractive indices of dielectric films according to the double refraction quantity of respective substrates. CONSTITUTION: A difference arises between the signal crosstalk quantity from lands 4 to grooves 5 and the signal crosstalk quantity from the grooves 5 to the lands 4 when the Kerr ellipticity at which an elliptically polarized light component intrudes into linearly polarized light is not zero in magneto-optical recording. If the Kerr ellipticity fluctuates, the signal crosstalk quantity between the lands and the grooves fluctuates of course. On the other hand, the values of the Kerr ellipticitys of the magnetic films and dielectric films are varied by controlling the thicknesses and refractive indices of the dielectric films. The Kerr ellipticity of the media is, thereupon, kept always zero if the films are formed by controlling the dielectric films and double refraction in such a manner that the double refraction quantity of the substrates is cancelled. The fluctuation in the quantity of the signal crosstalks between the lands and the grooves is thus lessened.