The present invention provides a liquid crystal composition and a liquid crystal display device thereof. The liquid crystal composition comprises at least one compound of general formula I and at least one compound of general formula II. The liquid crystal composition has a larger vertical dielectric constant (.sub.), a larger ratio of the vertical dielectric constant to the absolute value of dielectric anisotropy (.sub./||), a larger K.sub.ave value and a higher transmittance while maintaining an appropriate clearing point, an appropriate optical anisotropy, and an appropriate absolute value of the dielectric anisotropy, such that the liquid crystal display device comprising the same has a better contrast, a faster response speed and a better transmittance while maintaining an appropriate range of operating temperature and an appropriate threshold voltage.

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A LC lens and a liquid-crystal medium used in said LC lens, wherein the medium contains one or more compounds of each of formulae I and II

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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.

The present invention relates to liquid crystalline (LC) medium, to a method of its production and to the use of such LC media in polymer network liquid crystalline (PNLC) light modulation elements operated in the normally transparent mode. Furthermore, the present invention relates to such light modulation elements, as such, to the use of such light modulation elements as light shutters for transparent OLED displays, to the use of such light modulation elements in smart windows, and to a method of production of such light modulation elements according to the present invention.

The invention relates to the compounds of the formula I and to a liquid-crystalline medium based on a mixture of polar compounds which contains at least one compound of the formula I ##STR00001##
in which R.sup.1, ring A.sup.1, L.sup.1, L.sup.2, L.sup.3, L.sup.4, L.sup.5, L.sup.6, L.sup.7, L.sup.8, Z.sup.1 and m have the meanings indicated in claim 1 and to the use of the LC mixtures in electro-optical displays, especially for the self-aligning VA mode.

The present invention provides a liquid crystal composition and a liquid crystal display device thereof. The liquid crystal composition comprises at least one compound of general formula I and at least one compound of general formula II. The liquid crystal composition has a larger vertical dielectric constant (?.sub.?), a larger ratio of the vertical dielectric constant to the absolute value of dielectric anisotropy (?.sub.?/|??|), a larger K.sub.ave value and a higher transmittance while maintaining an appropriate clearing point, an appropriate optical anisotropy, and an appropriate absolute value of the dielectric anisotropy, such that the liquid crystal display device comprising the same has a better contrast, a faster response speed and a better transmittance while maintaining an appropriate range of operating temperature and an appropriate threshold voltage. ##STR00001##

The invention relates to dielectrically positive liquid crystalline media comprising a compound of formula I

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wherein the parameters have the meaning given in claim 1 and to liquid crystal displays comprising these media, especially to active matrix displays and in particular to TN and IPS mode displays.

A liquid crystal composition satisfying at least one of characteristics such as high maximum temperature of a nematic phase, low minimum temperature thereof, large optical anisotropy, large positive dielectric anisotropy and high stability to ultraviolet light, or having suitable balance regarding at least two of the characteristics; and a liquid crystal display device including such a composition and particularly including an encapsulated composition, and a liquid crystal display device serving as a constituent of a display device that allows switching of display between 2D and 3D. The liquid crystal composition contains a specific compound having large optical anisotropy as a first component and a specific compound having large positive dielectric anisotropy as a second component, and may further contain a specific compound having large optical anisotropy and further having high maximum temperature or low minimum temperature as a third component, and the liquid crystal display device includes the composition.

A liquid crystal compound represented by general formula F is useful as a liquid crystal composition and as a liquid crystal display device that contains the liquid crystal composition. The liquid crystal compound has a large clearing point, large optical anisotropy and sizable or large dielectric anisotropy absolute value under the condition of maintaining a suitable rotary viscosity, enabling the liquid crystal composition that contains the compound represented by general formula F has a large optical anisotropy, small rotational viscosity, high VHR (UV) and long low-temperature storage duration under the condition of maintaining proper clearing point, proper dielectric anisotropy absolute value and proper VHR (initial), and the liquid crystal display device that contains the liquid crystal composition of the present invention has good contrast, high response speed, high reliability and good low-temperature storage stability.

A liquid crystal compound represented by general formula F is useful as a liquid crystal composition and as a liquid crystal display device that contains the liquid crystal composition. The liquid crystal compound has a large clearing point, large optical anisotropy and sizable or large dielectric anisotropy absolute value under the condition of maintaining a suitable rotary viscosity, enabling the liquid crystal composition that contains the compound represented by general formula F has a large optical anisotropy, small rotational viscosity, high VHR (UV) and long low-temperature storage duration under the condition of maintaining proper clearing point, proper dielectric anisotropy absolute value and proper VHR (initial), and the liquid crystal display device that contains the liquid crystal composition of the present invention has good contrast, high response speed, high reliability and good low-temperature storage stability. ##STR00001##