Abstract: An optical disk recording device, an optical disk playback device, and an optical disk system have a large on-line capacity, a high speed data transfer speed, and a smooth data transfer speed. The optical disk recording device includes a plurality of recording units to record on a plurality of optical disks and a control unit that divides the data to be recorded between a plurality of optical disks, sends the divided data to the plurality of recording units, and fixes the amount of data recorded per unit time on each disk. In the optical disk playback device, a plurality of playback units replaces the plurality of recording units. The control unit controls, as substantially fixed, the total playback amount of data per unit time from the plurality of optical disks, and combines data from the plurality of optical disks played back by the playback units. In the optical system, the device accepts a magazine of optical disk cartridges that each house an optical disk.

Abstract: A mirror rotation angle detection mechanism is provided for an optical system having a mirror which is rotatable about an axis substantially on a reflection surface thereof at which a main beam of light is reflected. The mirror has a thin reflective layer with opposite surfaces that are nearly coplanar, and one of which constitutes the main beam reflection surface. The detection mechanism includes a light emitting member to irradiate a beam of detection light onto the opposite surface of the reflective layer. A light receiving element recieves the reflected detection beam, and an angle detection circuit detects the rotation angle of the mirror in accordance with the output of the light receiving element. According to a preferred embodiment, a condenser lens may be arranged between the light emitting member and the detection beam reflection surface.

Abstract: A method of manufacturing a vinyl chloride-coated steel sheet involving the steps of coating electron ray curable adhesives on the surface of the thin metal sheet, such as a zinc plated steel sheet or cold rolled steel sheet, laminating a vinyl choride film of decorative and corrosion resistant protecting property to the coated surface and irradiating electron rays the upper surface of the coated sheet with thereby bonding the film with the metal sheet as raw material, wherein the vinyl chloride film is formed by applying a calendering or extruding process to a blend including a vinyl chloride resin obtained by suspension polymerization and, from 20 to 40 parts by weight of a plasticizer, dialkyl tin mercaptide type stabilizer, an acryl oligomer type lubricant and, optionally, pigments and other ingredients.

Abstract: A method of manufacturing a vinyl chloride-coated steel sheet involving the steps of coating electron ray curable adhesives on the surface of a thin metal sheet, such as a zinc plated steel sheet or cold rolled steel sheet, laminating a vinyl chloride film of decorative and corrosion resistant protecting properties to the coated surface and irradiating the upper surface of the coated sheet with electron rays thereby bonding the film with the metal sheet, wherein the vinyl chloride film is formed by applying a calendering or extruding process to a blend including a vinyl chloride resin obtained by suspension polymerization and from 20 to 40 parts by weight of a plasticizer, dialkyl tin mercaptide type stabilizer, an acryl oligomer type lubricant and optionally, pigments and other ingredients.