Abstract: An enlarging unit comprises a concave Fresnel lens warped convexly toward an image forming unit side, the image forming unit is held between a light transmissible support plate warped convexly toward the image forming unit side and the enlarging unit warped convexly toward the image forming unit side, and peripheries of the support plate and the enlarging unit are fixed or semi-fixed. Thereby, deformation caused when the incident side and emission side micro-lens arrays are molded and deformation due to environmental temperature and humidity change are corrected, and both components are always maintained in close contact.

Abstract: In a description and drawings of the present application disclosed are, as the invention, (1) a projector for projecting an optimum image face having a convex configuration at a side of the projector, (2) a projecting system provided with the projector and a translucent screen with a substantially spherical configuration on which an image from the projector is formed, (3) a system for sensation provided with the projecting system, a seat at which a viewer is seated, a motion drive device for displacing the seat, a motion control device for controlling operation of the motion drive device, and an image control device for controlling an image projected by the projector while instructing the motion drive device to displace the seat in accordance with a change in the image, and (4) a method of manufacturing a screen provided with a light diffusing layer forming step of warming and softening a transparent thermoplastic resin sheet including a particle of a light diffusion material and pressing a light transmitting

Abstract: A multi-display apparatus includes a plurality of rear projection-type display devices each in which projection light from image sources is projected through projection lenses onto a rear projection surface of a rear projection screen to form a picture image on a front viewing surface of the rear projection screen, the plurality of rear projection-type display devices being combined together in contiguous relation to one another to form a large screen. An overall front viewing surface of the large screen is formed into a concave surface curved both in a horizontal visibility angle direction and a vertical visibility angle direction. A light-absorbing portion is formed on the front viewing surface of the rear projection screen, and the light-absorbing portion absorbs projection light which passes through one rear projection screen, and is incident as external light on another rear projection screen, thereby preventing a picture image from being degraded.

Abstract: A concave mirror which has rigidity higher than an aluminum foil mirror and is light-weight and low cost compared with a polished glass mirror is composed of at least one concave mirror unit of a synthetic resin material molded to a concave shape and an aluminum reflecting layer vapor deposited on a front or rear surface of the concave mirror unit. A low cost image display device capable of projecting an image onto the concave mirror without using any specially designed projection lens includes at least a projection type cathode ray tube having a flat or substantially flat phosphor surface panel and a transmission type screen and the concave mirror. A multi-screen system which includes a plurality of the image display devices juxtaposed to provide an increased horizontal view angle is provided. Further, a sensory integration system using the image display device is provided.

Abstract: A rear projection type image display apparatus having an arrangement that a projection distance of a projection lens thereof is shortened and a density of mounting of parts relating to an optical system and an electric system is made higher. Furthermore, a width of a rear portion of a housing of the rear projection type image display apparatus is reduced rearwards at any position from the upper portion to the lower portion thereof, and the lower portion of a back cover is depressed inwards. Thus, a space required to install the rear projection type image display apparatus can be reduced, the rear surface of the apparatus can be disposed on a wall without any gap when the apparatus is installed along the wall, and the overall body of the apparatus can be received deep into a corner of walls when the apparatus is installed at the corner.

Abstract: In a polarization transforming optics having a polarizing beam splitter (PBS) for transforming x-direction incident light flux from a metal halide light source into a single linearly (z direction) polarized light flux beam heading in the y direction and delivering the beam to, preferably, a light valve of a liquid crystal display (LCD) in a coordinate space, the PBS splits the incident light flux from the light source into split light flux beams, separates the split light flux beams into linearly polarized light flux beams having polarizing directions which are orthogonal to each other, and delivers two linearly polarized outgoing light flux beams having polarizing directions which are orthogonal to each other and heading in directions parallel to a polarizing direction plane. One of the two outgoing light flux beams is deflected by a single mirror to have the same heading direction and polarizing direction as those of the other.

Abstract: In a process for producing a conjugated diene copolymer, the improvement in which when copolymerizing a conjugated diene monomer with an ethylenically unsaturated nitrile monomer, at least one compound selected from a bifunctional peroxide represented by formulaR.sub.1 --OO--R.sub.2 --OO--R.sub.3 (I)wherein R.sub.1, R.sub.2 and R.sub.3 each denote a hydrocarbon group, anda bifunctional peroxycarbonate represented by formula ##STR1## wherein R.sub.4, R.sub.5 and R.sub.6 each denote a hydrocarbon group, said bifunctional peroxide and peroxycarbonate being soluble in said monomers, is used as a polymerization initiator.

Abstract: A novel rubbery copolymer comprising (A) 5 to 95% by weight of structural units based on 1,1-dicyano-2-vinylcyclopropane and (B) 95 to 5% by weight of structural units based on a 1,1-difluoro-2-vinylcyclopropane and having a weight average molecular weight, calculated for standard polystyrene, of 2,000 to 2,000,000 is provided by copolymerizing the 1,1-dicyano-2-vinylcyclopropane and the 1,1-difluoro-2-vinylcyclopropanes in the presence of a free radical initiator. This rubbery copolymer and its hydrogenated product give a vulcanizate having improved oil resistance, cold resistance, thermal resistance, sour gasoline resistance, alcohol-containing gasoline resistance and alcohol-containing sour gasoline resistance.

Abstract: A rubber composition capable of giving a vulcanizate having improved ozone resistance. The composition comprises a nitrile group-containing highly saturated polymer rubber having an iodine value of not more than 80, an organic peroxide, a crosslinking coagent and a quinoline-type stabilizer.

Abstract: An optical disc consists of a base plate, a reflective thin layer and a protective thin layer. As the base plate, polymethylmethacrylate is used. Since defects in the protective thin layer are a function of defects in the base plate, in order to reduce defects in the protective thin layer, defects in the base plate are reduced. For reducing defects in the base plate, a copolymer of methyl methacrylate and methyl acrylate is used.

Abstract: A information recording medium has characteristics of high sensitivity and high density. The medium has a double layer formed on a transparent substrate, the double layer comprising a highly transparent recording layer, for example, Sb.sub.2 Se.sub.3 layer and a highly reflective layer, for example, Bi layer. The highly transparent recording layer includes Bi so as to set a minimum value of a reflection factor in prerecording 8 to 16 percentages.

Abstract: A process for producing a hydrogenated conjugated diene polymer, which comprises hydrogenating the carbon-carbon double bonds of a conjugated diene polymer in a solvent using a supported catalyst composed of a hydrogenating catalyst supported on a carbon carrier having an average particle diameter of 5 m.mu. to 10.mu. and a specific surface area of 5 to 2000 m.sup.2 /g, and after the hydrogenation reaction has been completed, separating and recovering the hydrogenated conjugated diene polymer from the solution of the hydrogenated polymer without separating the catalyst therefrom.

Abstract: NBR containing at least 10% by weight of combined acrylonitrile is produced by polymerizing acrylonitrile and butadiene in emulsion in the presence of a linear alkyl sulfate mixture containing at least 60% by weight of a linear alkyl sulfate having 6 to 10 carbon atoms.

Abstract: A sulfur-curable acrylic rubber composition is provided which comprises [I] 100 parts of an acrylic rubber resulting from the copolymerization in the presence of a radical initiator of (1) 30 to 89.5% by weight of at least one alkyl acrylate with the alkyl group containing 1 to 8 carbon atoms, (2) 0.5 to 10% by weight of at least one monomer of the general formula ##STR1## wherein R.sub.1 represents a hydrogen atom or a methyl group, and R.sub.2 and R.sub.3, independently from each other, represent an alkyl group containing 1 to 3 carbon atoms, (3) 10 to 60% by weight of at least one alkoxyalkyl acrylate with the alkoxy group containing 1 to 4 carbon atoms and the alkylene group containing 1 to 4 carbon atoms, and 0 to 30% by weight of at least one of monovinyl and monovinylidene unsaturated compounds other than the said compounds; and [II] 1 to 5 parts by weight of a metal compound, and [III] 0.2 to 5 parts by weight, as sulfur, of at least one of sulfur and sulfur-containing organic compounds.

Abstract: A process for producing a sulfur-curable acrylic rubber is provided which comprises radical-copolymerizing (1) an alkyl acrylate with (2) an alkenyl acrylate or methacrylate, or radical-copolymerizing (1) an alkyl acrylate, (2) an alkenyl acrylate or methacrylate, (3) an alkoxyalkyl acrylate and optionally (4) acrylonitrile. These acrylic rubbers can be cured at a rate as fast as those for curing diene-type rubbers, and the cured products exhibit superior properties without long heat-treatment after curing.

Abstract: A rubber composition for tire treads includes (Ia) an oil-extended rubber having a Mooney viscosity (ML.sub.1+4, 100.degree. C) of 20 to 70 which is prepared by adding 20 to 80 parts of a hydrocarbon oil to 100 parts by weight of a rubber terpolymer which is composed of 2 to 13% by weight of combined styrene, 15 to 70% by weight of combined 1,3-butadiene and 17 to 83% by weight of combined 1,3-pentadiene with the dienes having a total 1,4-bond content of at least 65 mole%, (II) vulcanization additives, and (III) 30 to 110 parts by weight, per 100 parts by weight of the oil-extended rubber (Ia), of a carbon black for rubber having an average particle diameter of not more than 60 m.mu. the rubbery copolymer has a glass transistion temperature of -70.degree. to -20.degree. C., and is produced by emulsion-polymerization at 0.degree. to 30.degree. C.

Abstract: A novel vulcanized product of a terpolymer is prepared by heating acrylonitrile/butadiene-1,3/2-methyl butadiene-1,3 comprising 15 to 45% by weight of combined acrylonitrile and 85 to 55% by weight of combined diene, said combined diene consisting of 65 to 95% by weight of combined butadiene-1,3 and 35 to 5% by weight of combined 2-methylbutadiene-1,3, in the presence of a vulcanizing agent at a temperature of 100.degree. to 220.degree. C. for about 1 minute to 2 hours.

Abstract: A radical polymerization initiator comprising as an active ingredient a hydroperoxide of disproportionated or hydrogenated rosin acid or its alkali metal or ammonium salt.The initiator is prepared by contacting disproportionated or hydrogenated rosin acid or its alkali metal or ammonium salt with molecular oxygen in water or an organic solvent at a temperature of 0.degree. to 150.degree.C. to form its hydroperoxide.

Abstract: A process for producing a sulfur-curable acrylic rubber is provided which comprises radical-copolymerizing (1) an alkyl acrylate with (2) an alkenyl acrylate or methacrylate, or radical-copolymerizing (1) an alkyl acrylate, (2) an alkenyl acrylate or methacrylate, (3) an alkoxyalkyl acrylate and optionally (4) acrylonitrile. These acrylic rubbers can be cured at a rate as fast as those for curing diene-type rubbers, and the cured products exhibit superior properties without long heat-treatment after curing.