A material used in an element for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz. A liquid crystal composition containing at least one compound selected from a group of compounds represented by Formula (1), at least one compound selected from a group of compounds represented by Formula (2) and at least one compound selected from a group of compounds represented by Formula (3).

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For example, R.sup.1, R.sup.21, R.sup.22, R.sup.31, and R.sup.32 are alkyls having 1 to 12 carbon atoms; a ring A.sup.1 is 1,4-phenylene; Z.sup.11, Z.sup.13, Z.sup.21, Z.sup.23, Z.sup.31, and Z.sup.33 are single bonds; Z.sup.12, Z.sup.22, and Z.sup.32 are —C≡C— or —C≡C—C≡C—; L.sup.13 to L.sup.16, L.sup.21 to L.sup.23, and L.sup.31 to L.sup.36 are hydrogen or fluorine; Y.sup.11 and Y.sup.12 are hydrogen or fluorine; and n.sup.1 is 0.

A compound is represented by general formula (I), a liquid-crystal composition contains this compound, and devices are made using this liquid-crystal composition.

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Having a large refractive-index anisotropy Δn and a sufficiently high Tni, highly compatible with liquid-crystal compositions, and exhibiting a high dielectric anisotropy in the radiofrequency range, the compound is a useful material for RF phase shifters, phased-array antennae, image recognition devices, distance meters, liquid-crystal displays, liquid-crystal lenses, and birefringent lenses for 3D image display, among other devices.

The present invention relates to an optical component comprising a liquid crystal (LC) medium, operable in the infrared region of the electromagnetic spectrum. The invention further relates to the use of said LC medium in the infrared (IR) region and to devices comprising said optical component. The present invention further relates to an LC medium comprising one or more compounds of the formulae I, II, and III

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in which the occurring groups and parameters have the meanings defined in claim 1, and preferably one or more compounds of the formula RO

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in which the occurring groups and parameters have the meanings defined in claim 2.

An optical film includes a plurality of helically arranged liquid crystals and organic solid crystal structures at least partially surrounding the plurality of helically arranged liquid crystals. A method of making the optical film includes obtaining a substrate with an alignment layer and a film of a first solution on the alignment layer. The first solution includes liquid crystals and organic crystal molecules. The liquid crystals form a plurality of helically arranged liquid crystals on the alignment layer. The method also includes forming organic solid crystal structures by crystallizing the organic crystal molecules. The organic solid crystal structures at least partially surround the plurality of helically arranged liquid crystals.

The present invention relates to an optical article comprising a birefringent liquid crystal composition, said composition comprising more than 30% by weight based on the total weight of the composition of tolane compounds of formula R—S—Z.sup.1-A-Z.sup.2—NCS, in which R is a substituted or unsubstituted, linear or branched alkyl group, Z.sup.1 and Z.sup.2 are aryl groups, and A is an ethynyl group, an arylethynyl group or an ethynylarylethynyl group.

A method and apparatus for improved switching speed and/or tunability for radio-frequency (RF) devices are described. In one embodiment, a liquid crystal (LC) component comprises an LC structure in a mixture with right-handed (R) and left-handed (S) chiral dopants.

A laminate is provided having excellent adhesiveness between a light absorption anisotropic film and a barrier layer, a manufacturing method of the laminate, and an image display device using the laminate. A laminate having: a barrier layer A; and a light absorption anisotropic film B, in which the barrier layer A is adjacently provided on the light absorption anisotropic film B, a relationship between a highest content of a compound A1 contained in the barrier layer A and a highest content of a compound B1 contained in the light absorption anisotropic film B satisfies a relationship in which a value of distance calculated from Hansen solubility parameters and represented by Formula (I) is within a range of 0.0 to 5.0, and the light absorption anisotropic film B contains a component same as the compound A1.
distance={4×(δ.sub.D(B1)−δ.sub.D(A1)).sup.2+(δ.sub.P(B1)−δ.sub.P(A1)).sup.2+(δ.sub.H(B1)−δ.sub.H(A1)).sup.2}.sup.0.5  (I)

As a material used in an element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz, a liquid crystal composition is required, which has a high upper limit temperature of a nematic phase, a low lower limit temperature of a nematic phase, large dielectric anisotropy and a small tan δ in a frequency region where the phase control of an electromagnetic wave signal is performed, and stability against heat, and which has an excellent balance of the characteristics. A liquid crystal composition which is used in an element for phase control of an electromagnetic wave signal having any frequency from 1 GHz to 10 THz, the liquid crystal composition containing at least one compound selected from compounds represented by Formula (1) as a first component.

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The present invention relates to components for high-frequency technology, especially microwave components for high-frequency devices, such as devices for shifting the phase of microwaves, tunable filters, tunable metamaterial structures and electronic beam steering antennas (e.g. phased array antennas) comprising a liquid-crystalline medium, and to the liquid-crystalline medium used therein, wherein the liquid crystal medium comprises one or more compounds of formula S

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as defined in claim 1.

A liquid crystal dielectric applicable to high-frequency electromagnetic wave modulation has a clearing point of the liquid crystal dielectric higher than 110° C., a low-temperature storage temperature lower than −20° C., and an optical anisotropy greater than 0.35. The liquid crystal dielectric includes: one or more compounds selected by general formula I, which occupy 30-80% of the total weight of the liquid crystal dielectric, and one or more compounds selected by general formula II and/or general formula III, which occupy 20-70% of the total weight of the liquid crystal dielectric. The liquid crystal dielectric has good low-temperature stability, high dielectric anisotropy, a high phase width, appropriate rotary viscosity, appropriate optical anisotropy, low dielectric loss, and a low loss tangent, exhibits strong high-frequency electromagnetic wave tuning capability, is specifically suitable for electromagnetic wave modulation in microwave or millimeter wave areas, and has a good application prospect in liquid crystal phase shifters.

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