Abstract: The present invention provides an optical information recording medium of excellent signal quality in high density recording onto a semitransparent information layer, its manufacturing method and a manufacturing apparatus. The optical information recording medium of the present invention includes at least a semitransparent information layer disposed between a circular transparent substrate and a protective substrate, in which the information layer has spiral grooves for guiding a light beam, and also includes a recording film capable of recording/reproducing information thereon/therefrom by changing at least in two states detectable optically by irradiation of the light beam from the transparent substrate side, and the difference in film thickness of slope portions of the inner circumferential side and outer circumferential side of the groove is within ±10% in the entire region for recording/reproducing information.

Abstract: The present invention pertains to an information recordable and erasable, phase-change optical disk, particularly to a 4.7GB DVD-RAM disk. Provided is a recording medium having a short tact time in layer formation, and superior jitter characteristics, cross erasing characteristics, and cycle characteristics. The recording medium has at least a reflective layer, a recording layer, a light-incident-side protective layer, a first resin layer, and a light-incident-side substrate in this order on a substrate formed with a guide groove. The first resin layer is formed over the recording layer by a gap between 1 nm and 50 nm.

Abstract: An optical information recording medium includes a substrate for allowing laser light to be transmitted therethrough; a first protective layer for protecting the substrate: a recording layer for allowing information to be recorded thereon by laser light irradiation; a second protective layer for protecting the recording layer: an absorption layer for absorbing heat generated by the laser light, and a reflective layer for reflecting the laser light.

Abstract: An optical information recording medium is provided in which recording can be performed at higher speed with higher density by enabling the cooling power of the recording medium to be improved, the overwritten-mark distortion to be decreased, and an medium with high transmittance to be obtained. The optical information recording medium is formed by laminating, sequentially on a substrate: a protective layer; an interface layer; a recording layer whose optical characteristics are varied reversibly by irradiation of a laser beam; an interface layer; a light transmittance type reflective layer that transmits the laser beam with a wavelength &lgr;; and a thermal diffusion layer. A thickness d of the thermal diffusion layer is set to be within a range of 0<d≦({fraction (5/16)})&lgr;/n or ({fraction (7/16)})&lgr;/n≦d≦(½)&lgr;/n, wherein n indicates a refractive index of the thermal diffusion layer.

Abstract: A continuous plasma CVD apparatus, characterized in that frequency of high-frequency bias is in the range of 50-900 KHz, a blocking condenser is provided between a thin film and a high-frequency source so that the product C·f of electrostatic capacity C of the blocking condenser and frequency f of the high-frequency source is 0.02 [F·Hz] or more, and the total of impedances of all the rollers provided in the route of from a substrate unwind roller to a rotating drum is 10 k&OHgr; or more and the total of impedances of all the rollers provided in the route of from the rotating drum to a wind roller is 10 k&OHgr; or more. According to this apparatus, it becomes possible to continuously form a film without causing damage and deterioration of the substrate.

Abstract: A continuous plasma CVD apparatus, characterized in that frequency of high-frequency bias is in the range of 50-900 KHz, a blocking condenser is provided between a thin film and a high-frequency source so that the product C·f of electrostatic capacity C of the blocking condenser and frequency f of the high-frequency source is 0.02 [F·Hz] or more, and the total of impedances of all the rollers provided in the route of from a substrate unwind roller to a rotating drum is 10 k&OHgr; or more and the total of impedances of all the rollers provided in the route of from the rotating drum to a wind roller is 10 k&OHgr; or more. According to this apparatus, it becomes possible to continuously form a film without causing damage and deterioration of the substrate.

Abstract: A continuous plasma CVD apparatus, characterized in that frequency of high-frequency bias is in the range of 50-900 KHz, a blocking condenser is provided between a thin film and a high-frequency source so that the product C·f of electrostatic capacity C of the blocking condenser and frequency f of the high-frequency source is 0.02 [F·Hz] or more, and the total of impedances of all the rollers provided in the route of from a substrate unwind roller to a rotating drum is 10 k&OHgr; or more and the total of impedances of all the rollers provided in the route of from the rotating drum to a wind roller is 10 k&OHgr; or more. According to this apparatus, it becomes possible to continuously form a film without causing damage and deterioration of the substrate.

Abstract: A continuous plasma CVD apparatus, characterized in that frequency of high-frequency bias is in the range of 50-900 KHz, a blocking condenser is provided between a thin film and a high-frequency source so that the product C.multidot.f of electrostatic capacity C of the blocking condenser and frequency f of the high-frequency source is 0.02 [F.multidot.Hz] or more, and the total of impedances of all the rollers provided in the route of from a substrate unwind roller to a rotating drum is 10 k.OMEGA. or more and the total of impedances of all the rollers provided in the route of from the rotating drum to a wind roller is 10 k.OMEGA. or more. According to this apparatus, it becomes possible to continuously form a film without causing damage and deterioration of the substrate.

Abstract: A magnetic recording medium having an improved S/N is provided by using a ferromagnetic metal thin film having a mean value of a fluctuation field of magnetic viscosithy measured at 25.degree. C. in a region in which an applied magnetic field strength is 0.8 to 1.2 times as large as a remanence coercivity, of between 15 Oersteads and 30 Oersteads, and preferably a coercivity of between 700 Oersteads and 2000 Oersteads.