Magneto-optical disk and its recording and reproducing method and device

PURPOSE: To improve the recording density of the magneto-optical disk which records, reproduces and erases of information by using a laser beam and an externally impressed magnetic field and to improve handleability. CONSTITUTION: An information recording film 3 consists of a magnetic material having perpendicular magnetic anisotropy and exhibiting a magneto-optical effect and consists of a ROM region where the information is previously recorded non-volatizably and a RAM region where a user rewritably records the information. The information is recorded by changing the direction of the axis of easy magnetization in parallel with the recording film plane and the information is reproduced by detecting the difference in the magneto-optical effect by the difference in the direction in the ROM region. The information is recorded by inverting the directions of magnetization and the information is reproduced by detecting the difference in the magneto-optical effect by the difference in the forward and backward directions of the magnetization; for example, the difference in the rotating directions of the plane of polarization in the RAM region. COPYRIGHT: (C)1993,JPO&Japio