Abstract: A broadband cholesteric polarizer is described, as well as a method of manufacturing such a polarizer. Said polarizer comprises an optically active layer of a polymer material having a cholesteric order, said material being oriented so that the axis of the molecular helix extends transversely to the layer. In accordance with the invention, the polarizer is characterized in that the pitch of the molecular helix in the layer is varied in such a manner that the difference between the maximum pitch and the minimum pitch is at least 100 nm. The optically active layers are preferably provided on substrates which bring about a conversion of circularly polarized light into linearly polarized light. Three different methods of manufacturing such broadband polarizers are described.

Abstract: A liquid-crystal display device having an improved picture quality is obtained by rendering the iso-contrast curves rotationally symmetrical. This is obtained by means of a double cell construction, in which two identical TN-cells are present between two parallel polarizers, which TN cells are arranged relative to each other in such a manner that the director at the front face of the second cell encloses an angle of 180.degree. with the director at the front face of the first cell. A polarizer is provided between both cells, the direction of polarization of said polarizer extending perpendicularly to the direction of polarization of the two other polarizers.

Abstract: A liquid-crystal display device having a twisted nematic liquid-crystalline material is provided with a layer of an optically anisotropic material to obtain a colourless display device which is rich in contrast. The optically anisotropic material is a synthetic resin composition comprising a polymer network having a helicoidal order manufactured from a curable liquid-crystalline composition having a chiral dopant.

Abstract: A liquid crystalline material in the form of an anisotropic gel comprising a polymerized liquid crystalline material and a low-molecular weight liquid crystalline material, can be used in a display cell, said polymerized material forming a permanently oriented network in the low-molecular weight liquid crystalline material.

Abstract: By using an adhesive layer (9) between a mount (3) and an optical component (5), which adhesive layer comprises liquid crystalline monomers, the polymerization shrinkage can be minimized in the desired directions X and Y if the monomers are oriented in the Z-direction by an external field before they are polymerized.

Abstract: The invention relates to a method of providing a surface layer on a substrate, which surface layer can bring about an inclined orientation of the molecules of the liquid crystalline layer applied to the surface layer at the interface between the surface layer and the liquid crystalline layer. The surface layer is manufactured from a liquid crystalline auxiliary layer in which the orientation of at least a part of the molecules is permanently fixed.

Abstract: Glass capillaries having an internal diameter of a few micrometers are internally provided with a relatively thick polymer film by in-situ polymerisation of suitable monomers and/or oligomers in a solvent. The said polymer film is suitable as a stationary phase for liquid chromatography.

Abstract: The invention relates to an optical glass fibre 1 having a synthetic resin coating which consists of at least two layers 2 and 3 in which the first layer 2 is formed from an elastomer forming material which can be cured by exposure to actinic radiation, and in which the optical glass fibre exhibits a great tensile strength, a small risk of static fatigue fracture and a low ageing rate, owing to the fact that the synthetic resin composition comprises between 0.1 and 5% by weight of one or more phosphorus compounds of the following structural formula: ##STR1## wherein n has a value of 1 or 2 and wherein R represents an organic group, preferably an organic group which co-reacts during curing of the elastomer forming material and is built into the polymeric network thus formed.

Abstract: Glass capillaries having an internal diameter of a few micrometers are internally provided with a relatively thick polymer film by in-situ polymerization of suitable monomers and/or oligomers in a solvent. The said polymer film is suitable as a stationary phase for liquid chromatography.

Abstract: In a polarization-sensitive beam splitter 10 having a polarization-separating layer 13 interposed between two transparent elements 11, 12, the two transparent elements consist of non-birefringent material and the polarization-separating layer is a polarizing birefringent oriented polymer adhesive layer. The polarization-separating layer is manufactured from a curable synthetic resin composition comprising liquid-crystalline monomers or oligomers, the molecules in the curable synthetic resin composition being oriented uniaxially after which the synthetic resin composition is cured.

Abstract: A method of manufacturing a polarization filter, in which a mixture of a liquid crystalline diacrylate monomer or dimethacrylate monomer and a dichroic colorant is provided on a substrate, oriented and polymerized by exposing it to radiation, as well as a polarization filter which is manufactured according to the above method, and a display comprising the polarization filter.

Abstract: A method of manufacturing a laminated element, in which a substrate 1 is provided with a coating 2 of a liquid-crystalline monomer, in accordance with formula 1, which is oriented by means of an external force, in particular a magnetic field 3, and subsequently subjected to radiation 4, so that a pattern 5 of coating 2 is polymerized and the orientation is fixed, as well as a laminated element, such as an optical component, obtained in accordance with the method.

Abstract: An optical fiber provided with a synthetic resin coating, comprising a glass fibre, a first enveloping layer of a synthetic rubber having a modulus of elasticity from 0.1 to 10 MPa and a subsequent enveloping layer of a synthetic resin having a larger modulus of elasticity than the first layer, obtains a large mechanical resistance and a high insensitivity to temperature variations within the range from -60.degree. C. to +80.degree. C., in that the thickness of the first layer is from 5 to 20 .mu.m and in that the modulus of elasticity of the second layer is more than 1000 MPa.

Abstract: Picture display cell, method of forming an orientation layer on a substrate of the picture display cell and monomeric compounds for use in the orientation layer.The picture display cell comprising two transparent plates having an electrode with thereon an orientation layer and a sealing ring between the ends of the plates, a liquid crystalline material being present in the space between the plates and the ring, the orientation layer being formed from a monomer or a low molecular compound which is first oriented in a field.

Abstract: The invention relates to a method of manufacturing an optical fibre which is provided with a synthetic resin cladding and which comprises at least one layer of oriented molecules which is obtained by first orienting a liquid crystalline curable synthetic resin composition and then curing it. The orientation process is carried out readily and efficaciously by rubbing the surface of the fibre before the curable synthetic resin composition is applied thereto.

Abstract: Method of manufacturing an optical fibre having a synthetic resin coating and optical fibre having a synthetic resin coating manufactured according to the method. The invention provides a method of rapidly coating an optical fibre with two layers of a synthetic resin, the first layer being formed from a reactive molten synthetic resin material. This molten synthetic resin material is solidified by cooling after which the second layer, which can be any customary curable synthetic resin composition, is applied. Next, both layers are cured together, for example, by exposure to UV-light. The reactive molten synthetic resin material comprises at least two acrylate ester groups per molecule.

Abstract: The invention provides an optical glass fibre having a synthetic resin coating and a method of manufacturing same, the first layer of the synthetic resin coating being formed from a curable polyether urethane acrylate composition.The glass transition temperature of the synthetic rubber formed after curing is reduced to -50.degree. C. or lower by increasing the molecular weight of the polyether urethane acrylate and, if necessary, by using aromatic instead of aliphatic urethanes. During coating the viscosity is low due to the presence of monofunctional acrylates of low viscosity. The curable synthetic composition exhibits a high curing rate.

Abstract: The invention provides an optical glass fiber having a synthetic resin cladding, in which the first layer of the synthetic resin cladding is formed from a curable synthetic resin composition which comprises a polyurethane acrylate and a siloxane copolymer containing acrylate groups.The synthetic rubber obtained by curing has the suitable properties of polysiloxane claddings, and additionally a greater mechanical strength as well as a greater resistance to wear.

Abstract: The invention provides an optical fibre having a synthetic resin cladding, comprising a glass fibre, a first cladding layer of a synthetic rubber and a subsequent cladding layer of a synthetic resin the molecules of which are oriented substantially in the longitudinal direction of the glass fibre, in which a low application temperature, a low pressure and a high cladding rate can be used in that the oriented synthetic resin is formed from a curable synthetic resin composition which comprises one or more oligomeric compounds the molecules of which comprise reactive groups and the molecular weight of which is smaller than 5000.The invention further relates to a method of manufacturing such an optical fibre and a device for cladding a glass fibre with a curable synthetic resin composition in which an elongation flow in the curable synthetic resin composition is produced to effect the orientation in the curable synthetic resin composition.

Abstract: The invention provides an optical glass fibre having a synthetic resin cladding and a method of manufacturing same, in which the first layer of the synthetic resin cladding is formed from a curable polysiloxane composition.The curing rate is increased by the presence of acrylate groups. The refractive index (exceeding 1.46) and the glass transition temperature (lower than -50.degree. C.) can be adjusted by the ratio of the dimethyl siloxane groups, methyl phenyl siloxane groups and diphenyl siloxane groups present. The curing rate can furthermore be increased by the addition of monomeric acrylate compounds.