Abstract: A magneto-optical recording and reproducing device is provided with a magneto-optical disk for reproducing recorded information using light, a semiconductor laser, an objective lens for converging a light beam emitted from the semiconductor laser onto the magneto-optical disk and a light interrupting member for interrupting a portion of a light beam before it is incident on the objective lens. The magneto-optical disk is composed of a readout layer which is predominant in in-plane magnetization, and in which a transition occurs to be predominant in perpendicular magnetization as temperature thereof is raised and a recording layer for recording thereon information using a perpendicular magnetization. In this arrangement, since the light interrupting member is provided, a light spot can be made smaller, thereby improving a recording density.

Abstract: A magneto-optical disk has a recording layer whereon recorded bits are formed by the magnetic field modulation method and a readout layer whose axis of easy magnetization is parallel to the recording layer at room temperature, and varies to be perpendicular to the recording layer within a predetermined temperature range between room temperature and the Curie temperature. During reproduction of the recorded bits the first semiconductor laser emits a heating-use light beam to form the first light spot on the readout layer Thus, a ring-shaped region corresponding to the predetermined temperature range exhibits perpendicular magnetic anisotropy and the recorded bits are copied from the recording layer onto the ring-shaped region. As the first light spot is shifted, the ring-shaped region as a readout window of recorded bits is also shifted.

Abstract: A magneto-optical storage device having a configuration wherein a first AlN film, a Pt/co multi-layer film formed by alternately depositing Pt and Co, a second AlN film, and an Al reflective film are successively laminated on a substrate in this order. Assuming that respectively the thickness of the first AlN film is .delta.AlN (1); that of the second AlN film is .delta.AlN (2); that of the Pt single layer is .delta.Pt; that of the Co single layer is .delta.Co; and the total thickness of the Pt/Co multi-layer film is .delta.Pt/Co, each thickness of those layers is set to range within: 50 nm .ltoreq..delta.AlN (1).ltoreq.200 nm; 120 nm.ltoreq..delta.AlN (2).ltoreq.140 nm; 0.6 nm.ltoreq..delta.Pt.ltoreq.1.0 nm; 0.3 nm.ltoreq..delta.Co.ltoreq.0.6 nm; and 15 nm.ltoreq..delta.Pt/Co.ltoreq.20 nm.

Abstract: A magnetic recording and reproducing apparatus using a recording medium made of a ferrimagnetic material, comprises a magnetic head for magnetically recording information on a recording area of a selected information recording track on a recording medium having a plurality of tracks and for magnetically reproducing the information from the recording medium, the magnetic head has a width larger than that of the width of the selected information recording track of the recording medium. For recording, light beams are radiated from a first light source on the recording area of the selected information recording track upon which recording is to be performed tracks to raise the temperature of the irradiated area to approximately a Curie temperature so as to allow recording only on that area.

Abstract: Disclosed is a magnetic recording medium having a magnetic layer composed mainly of a magnetic powder and a resin binder, wherein the magnetic layer comprises (a) an ester compound comprising (a-1) an ester compound represented by the following formula (1): ##STR1## wherein R stands for a branched alkyl group having 13 carbon atoms,(a-2) butyl stearate and (a-3) butoxyethyl stearate, and (b) carbon black comprising (b-1) carbon black having an average single particle size of 10 to 50 m.mu. and (b-2) carbon black having an average single particle size of 200 to 1,000 m.mu..This magnetic recording medium has an excellent durability and is utilized as a floppy disk or the like.