| 摘要 |
PURPOSE:To obtain a new optical recording medium which has raised the recording surface density of the optical recording medium by about one figure, by constituting it of an ultrafine grain consisting of a magnetic material or a dielectric, and a high polymer material for holding the ultrafine grain. CONSTITUTION:An ultrafine grain 1 having a shape anisotropy is mixed into a linear polymer 2. A laser irradiating part 3 is heated above a glass transition temperature at which a thermal expansion coefficient increases suddenly. In this state, a Co ultrafine grain 1' is oriented in the vector direction of a magnetic field H by impressing a magnetic field H4 from the outside. When the laser radiation is cut off, the irradiated part grows cold quickly and the fine grain is oriented and recorded. A read-out method is reproduced by limiting the laser power at the time of read-out so that a temperature rise of a read-out part becomes below the temperature Tg. By this theory, polyimide is used as a target for spattering, barium ferrite is used as other target, and sputtering is executed simultaneously. This composite film is heated to above the temperature Tg of a polyimide thin film by a laser, and oriented by impressing an electric field E. At the time of read-out, the laser power is limited so as to become below the temperature Tg, and a polarization angle of light is read. |
