A method and apparatus is disclosed herein 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.

The present invention relates to liquid-crystalline media comprising at least one compound of the formula I and at least one compound of the formula II
or at least one compound of the formula I and at least one compound of the formula III
or at least one compound of the formula II and at least one compound of the formula III
or at least one compound of the formula I and at least one compound of the formula II and at least one compound of the formula III: ##STR00001##
in which the parameters have the meaning indicated in Claim 1, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

The present invention relates to liquid-crystalline media comprising one or more polymerisable compounds, preferably of formula P

P.sup.a-(Sp.sup.a).sub.s1-(A.sup.1-Z.sup.1).sub.n1-A.sup.2-Q-A.sup.3-(Z.sup.4-A.sup.4).sub.n2-(Sp.sup.b).sub.s2-P.sup.bP

and one or more compounds selected from the group of compounds of

##STR00001##

in which the parameters have the meaning indicated in Claim 1, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

The present invention relates to liquid-crystalline media comprising one or more compounds selected from the group of compounds of formulae I, II and III,

##STR00001##

in which the parameters R.sup.1-R.sup.3, Z.sup.21, Z.sup.31, Z.sup.32 and rings A.sup.11, A.sup.12, A.sup.13, A.sup.21, A.sup.22, A.sup.31, and A.sup.32 are as defined herein, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

The present invention relates to liquid crystal media and to high frequency components comprising same, especially microwave components for high-frequency devices, such as devices for shifting the phase of microwaves.

The present invention relates to liquid-crystalline media comprising one or more compounds selected from the group of compounds of formulae I, II and III, ##STR00001##
in which the parameters R.sup.1-R.sup.3, Z.sup.21, Z.sup.31, Z.sup.32 and rings A.sup.11, A.sup.12, A.sup.13, A.sup.21, A.sup.22, A.sup.31, and A.sup.32 are as defined herein, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

The present disclosure relates to novel mesogenic compounds, to liquid crystal compositions (liquid-crystalline media) comprising them and suitable for high-frequency technology, and to high-frequency devices using them, such as phase shifters, antennas, tunable filters, switching devices, e.g. operated in the microwave region, to a process for preparing said compositions. A liquid-crystalline medium of the present disclosure includes: at least one compound of the formula I and at least one compound of the formula II; or at least one compound of the formula I and at least one compound of the formula III; or at least one compound of the formula II and at least one compound of the formula III; or at least one compound of the formula I and at least one compound of the formula II and at least one compound of the formula III. The present disclosure makes it possible to create liquid crystal compositions with high optical anisotropy (n), a positive dielectric anisotropy () and a wide temperature range of the nematic phases.

The present invention relates to a device for high-frequency technology, or for the microwave region and millimeter wave region of the electromagnetic spectrum, characterized in that it contains a liquid-crystal medium which consists of one or more compounds, which one or more compounds, which contain 6 to 15 five-, six- or seven-membered rings, preferably 1,4-linked phenylene rings, or in that it contains a liquid-crystal medium which itself comprises a component A, which itself consists of one or more of the said compounds, which one or more compounds, which contain 6 to 15 five-, six- or seven-membered rings, preferably 1,4-linked phenylene rings. The present invention additionally relates to compounds of the formula (I), in which the parameters have the meanings given in the text, and to the corresponding, novel liquid-crystal media, to the use and preparation thereof, and to the production and use of the devices. The devices according to the invention are particularly suitable phase shifters in the microwave and millimeter wave region, for microwave and millimeter wave array antennas and very particularly for so-called tunable reflectarrays.

Isothiocyanatoethynylbenzene derivatives of formula I

##STR00001##

liquid crystal media comprising the isothiocyanatoethynylbenzene derivatives, and 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), and devices comprising said components. Further, an optical component comprising said liquid-crystalline media, operable in the infrared region of the electromagnetic spectrum, the use of said LC medium in the infrared (IR) region, and devices comprising said optical component.

A polymer film is provided, the polymer film comprises a liquid crystal polymer, comprising a soluble liquid crystal polymer and an insoluble liquid crystal polymer; and a polyimide polymer; wherein the polymer film has a thermal expansion coefficient between 0 and 60 ppm/t of 50 C. to 200 C., a water absorption rate less than 0.5%, a dielectric loss tangent of D.sub.f less than 0.005 at a frequency of 10 GHz, and a storage elastic modulus greater than 0.1 GPa at 310 C. A method for manufacturing the polymer film, the method for manufacturing the polymer film comprises steps: providing a liquid crystal polymer powder; providing a liquid crystal polymer glue; providing a polyamic acid glue; mixing the liquid crystal polymer powder, the liquid crystal polymer glue and the polyamic acid glue into a mixed solution, the mixed solution is made into a gel film.