A nematic liquid crystal composition having a high Δn and a high Δε in a liquid crystal material that enables greater phase control over electromagnetic waves in the microwave or millimeter wave range, and a liquid crystal element, a sensor, a liquid crystal lens, an optical communication device, and an antenna including the nematic liquid crystal composition. Specifically, a liquid crystal composition containing one or two or more compounds represented by general formula (i) in the specification and one or two or more compounds represented by general formula (ii) in the specification, and having a high Δn and a high Δε.

Provided is a liquid crystal composition satisfying at least one or having suitable balance regarding at least two of characteristics such as high maximum or low minimum temperature of a nematic phase, large optical anisotropy, large positive dielectric anisotropy and high stability to ultraviolet light, and a liquid crystal display device including such a composition, particularly an encapsulated liquid crystal display device, and a liquid crystal display device serving as a constituent of 3D lenses. The liquid crystal composition contains a specific compound having large optical anisotropy as a first component, and a specific compound having large optical anisotropy and large positive dielectric anisotropy as a second component; a specific compound having large positive dielectric anisotropy as a third component; and a specific compound having large optical anisotropy and further having high maximum or low minimum temperature as a fourth component, and the liquid crystal display device includes the composition.

A ferroelectric liquid crystal (FLC) material in a vertically aligned liquid crystal cell, comprising at least one chiral compound and at least one non-chiral liquid crystal compound, with a sub-micron scale helix pitch less than 300 nm, spontaneous polarization greater than 100 nC/cm2, and a tilt angle greater than 38 degrees. The ferroelectric liquid crystal (FLC) material provides an extremely large Kerr constant in a vertically aligned liquid crystal cell at the communication band of the light and therefore reduces the driving voltage and response time.

The present invention relates to heteroaromatic isothiocyanates of formula N

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as defined in claim 1, to liquid-crystalline media comprising one or more compounds of formula N and to high-frequency components comprising these media, 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.

Provided is a liquid crystal composition satisfying at least one or having suitable balance regarding at least two of characteristics such as high maximum or low minimum temperature of a nematic phase, large optical anisotropy, large positive dielectric anisotropy and high stability to ultraviolet light, and a liquid crystal display device including such a composition, particularly an encapsulated liquid crystal display device, and a liquid crystal display device serving as a constituent of 3D lenses. The liquid crystal composition contains a specific compound having large optical anisotropy as a first component, and a specific compound having large optical anisotropy and large positive dielectric anisotropy as a second component; a specific compound having large positive dielectric anisotropy as a third component; and a specific compound having large optical anisotropy and further having high maximum or low minimum temperature as a fourth component, and the liquid crystal display device includes the composition.

Provided are a liquid crystal compound satisfying at least one of physical properties such as high stability to heat or light, high maximum temperature of a liquid-crystal phase, low minimum temperature thereof, small viscosity, suitable optical anisotropy, large dielectric anisotropy and good compatibility with other liquid-crystal compounds, a liquid crystal composition containing the compound and a liquid crystal display device including the composition.

A compound is represented by formula (1), a liquid crystal composition contains the compound and a liquid crystal display device includes the composition.

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In formula (1), Ra and Rb are fluorine or alkyl; A.sup.0, A.sup.1 and A.sup.2 are 1,4-phenylene; Z.sup.1 and Z.sup.2 are a single bond or alkylene; one of Y.sup.1 and Y.sup.2 is fluorine, and the other is hydrogen; Rc is alkyl; and a and b are independently 0, 1, 2 or 3, and a sum of a and b is 0, 1, 2 or 3.