Patent ID: 6101153
Filing Date: 2000-08-08
Classification: G11B

Abstract:
An optomagnetic recording/reproducing apparatus for an optomagnetic recording medium, wherein the medium comprises a plurality of magnetic layers that are (i) laminated directly together or (ii) laminated together through non-magnetic layers, the optomagnetic recording medium having that magnetic characteristic in a temperature change of a hysteresis curve obtained by changing an external magnetic field applied to said plurality of magnetic layers, in which in the condition of a high temperature lower than the temperature of the optomagnetic recording medium upon irradiation with a laser beam at the time of recording/erasing and not higher than a Curie temperature, there exist at least three different external magnetic field regions according to the change of the applied external magnetic field, each of said external magnetic field regions providing the state of magnetization in which the total magnetization of said plurality of magnetic layers is single and stable in that the external magnetic field region, and in the condition of a low temperature around room temperature not higher than said high temperature, said at least three states of magnetization generated in accordance with the magnitude of the external field applied at the time of high temperature stably exist under the condition of the external magnetic field of zero, said apparatus comprising a driver for driving an optomagnetic recording medium and an optical head and a magnetic head disposed opposite to said optomagnetic recording medium mounted to said driver, wherein said magnetic head has at least two windings in one magnetic circuit and the respective windings are independently driven to apply a multi-stepped external magnetic field to said optomagnetic recording medium.