Abstract: The invention relates to a liquid crystal mixture characterised in that it comprises one or more photoreactive mesogens of formula I wherein the parameters and groups occurring are defined as indicated in claim 1, to a process for the fabrication of liquid crystal displays using these liquid crystal mixtures and to a liquid crystal display obtainable by this process. The invention further relates to new compounds of formula I.

Abstract: The invention relates to a liquid crystal mixture characterised in that it comprises one or more photoreactive mesogens of formula I wherein the parameters and groups occurring are defined as indicated in claim 1, to a process for the fabrication of liquid crystal displays using these liquid crystal mixtures and to a liquid crystal display obtainable by this process. The invention further relates to new compounds of formula I.

Abstract: The invention relates to a method of manufacturing a liquid crystal display device wherein a liquid crystal mixture having positive dielectric anisotropy or negative dielectric anisotropy is interposed between a first substrate and a second substrate, the liquid crystal mixture comprising liquid crystal molecules, a self assembling photoalignment agent, a polymerisable compound, and wherein said LC mixture is photoaligned by irradiation with linearly polarised ultraviolet light and then cured by irradiation with ultraviolet light.

Abstract: The invention relates to cinnamic acid derivatives of formula S wherein the radicals have the meaning indicated in claim 1, to a process for their preparation and their use as self assembling photoalignment agent in liquid crystal mixtures. The invention further relates to a process for the fabrication of a liquid crystal (LC) display device with homogeneous alignment by photoaligning a liquid crystal mixture with positive or negative dielectric anisotropy comprising one or more compounds of formula S and optionally a polymerizable compound, to the liquid crystal mixture comprising the self assembling photoaligning agent and optionally the polymerizable compound and to the LC display produced by said process.

Abstract: The invention relates to a method of manufacturing a liquid crystal display device wherein a liquid crystal mixture having positive dielectric anisotropy or negative dielectric anisotropy is interposed between a first substrate and a second substrate, the liquid crystal mixture comprising liquid crystal molecules, a self assembling photoalignment agent, a polymerisable compound, and wherein said LC mixture is photoaligned by irradiation with linearly polarised ultraviolet light and then cured by irradiation with ultraviolet light.

Abstract: The invention relates to cinnamic acid derivatives of formula S wherein the radicals have the meaning indicated in claim 1, to a process for their preparation and their use as self assembling photoalignment agent in liquid crystal mixtures. The invention further relates to a process for the fabrication of a liquid crystal (LC) display device with homogeneous alignment by photoaligning a liquid crystal mixture with positive or negative dielectric anisotropy comprising one or more compounds of formula S and optionally a polymerisable compound, to the liquid crystal mixture comprising the self assembling photoaligning agent and optionally the polymerisable compound and to the LC display produced by said process.

Abstract: The present invention relates to an electro-rheological fluid comprising particles of at least one inorganic or organic material suspended in a polar liquid crystalline medium, the use of such electro-rheological fluid in an haptic device, an haptic device itself, a method of the production of such haptic device and the use of such haptic device in electro-optical devices.

Abstract: The invention relates to a material combination comprising a first fluid comprising a liquid crystal material, and an electrically insulating second fluid substantially not miscible with the first fluid, and to an optical device using the same.

Abstract: The present invention relates to an electro-rheological fluid comprising particles of at least one inorganic or organic material suspended in a polar liquid crystalline medium, the use of such electro-rheological fluid in an haptic device, an haptic device itself, a method of the production of such haptic device and the use of such haptic device in electro-optical devices.

Abstract: The present invention relates to an improved sensor arrangement, a system and method for determining the rate of ice formation and how close conditions are to those at which ice will form on a surface, and to an improved sensor arrangement for use therein. The sensor arrangement comprises a means (11,12,14) for measuring the thermal lag, heating and cooling of a thermally conductive element, which is comprised of a first and second surface (15a, 15b), said first surface exposed to the environment, wherein the surface area of said first surface is smaller than the second surface. The step of ice detection may be performed by either a passive measuring system wherein the latent heat of ice formation is measured via the temperature differential across a Peltier element.

Abstract: A method of fabricating an electrode structure for a multilayer semiconductor device comprising a semiconductor layer having a first electrode layer in contact therewith and a second electrode layer separated there-from by a dielectric layer (8), the method comprising the steps of; applying a patterning material (20) only to selected areas of a support layer within the device so as to define the arrangement of the first electrode layer thereon; applying to the support layer a catalyst (24) adapted to be responsive to the patterning material (20); applying a conductive material (26) to the support layer so as to form the first electrode layer thereon; wherein the support layer, the patterning material (20) and the catalyst (24) cooperate such that the conductive material (26) is only deposited on the selected areas of the support layer to which the catalyst (24) has been applied. An thin film transistor (2) having a gate insulator layer (8) comprising an epoxide material.

Abstract: A bistable display device comprises two cell walls enclosing a sheet having a plurality of cavities each containing a rotatable bicoloured sphere within a liquid crystal material carrier (15), and electrodes for applying an electrical field. The spheres and cavities are provided with a surface alignment which imposes a substantially unidirectional director alignment on the liquid crystal material in contact with them. The elastic distortion free energy of the liquid crystal material in each cavity is arranged to be zero when the preferred direction of the suspended spheres coincides with that of the surrounding cavity, e.g. black upwards. It is also zero when the sphere is rotated through 180° to present its opposite hemisphere which has a contrasting optical appearance, e.g. black downwards. Between these two states, there is an energetic barrier determined by the elastic constants of the liquid crystal which provides both a threshold for switching and improved bistability.

Abstract: A polarisation independent optical switch comprises a dielectric layer (6) in which are formed a multiplicity of minute channels (7). These channels (7) are instilled with a liquid crystal fluid, especially a nematic liquid crystal (8). Electrodes (4, 5) are formed on each side of the dielectric layer between two cell walls (2, 3). Application of a voltage across the layer results in an effective change of the refractive index of the layer, and therefore modulates the phase of light traversing the layer (6).

Abstract: Liquid crystal devices are formed by a layer of a liquid crystal material enclosed between two cell walls, both carrying electrode structures, and one or both walls treated to align molecules of the liquid crystal material. Most alignment treatment give alignment and surface pretilt with a strong azimuthal and zenithal anchoring energy to contacting liquid crystal molecules. The invention reduces at least one of the azimuthal zenithal or translational anchoring energy to improve switching characteristics and optical performance by allowing movement of liquid crystal molecules at or close to the cell wall. The reduction of anchoring energy may be achieved by an oligomer or short chain polymer which is either spread on the surface or added to the liquid crystal material. The size of oligomer or short chain polymer is low enough that it does not appreciably phase separate from the liquid crystal material.

Abstract: A fluorinated phenyl compound having the general formula [1]: wherein each of s, v and x=0 or 1, each of t and u=1, 2 or 3, and each of y and z=0, 1 or 2; A, B and C are independently selected from conjugated cyclic moieties including heterorings and fused rings; R1 and R3 may be independently cyano, or (C1-C12)alkyl, (C1-C12)alkoxy, (C1-C11) alkoxycarbonyl or (C1-C11)alkylcarbonyloxy which may be fluoro- and/or cyano-substituted; R2=H or F; R4=H or F; and R5=H or F. Such compounds have high transverse dipole moments and are potentially useful in liquid crystal compositions and in devices including same.

Abstract: A liquid crystal device is provided with a pair of substrates (12, 16) containing a liquid crystal material (22). A wall structure comprising, for example, a plurality of walls (14) is provided between the two substrates. The wall structure provides mechanical strength to the device and resistance to flow of liquid crystal material which can cause deterioration in the device performance. The walls may extend in two mutually different directions (FIG. 8, 40) to provide mechanical strength and resistance to flow in two directions while the device can still be readily filled. The device is particularly applicable to a ferroelectric liquid crystal device.

Abstract: Compounds of formula ##STR1## are provided which may be used in a variety of devices including liquid crystal devices, piezoelectric devices, pyroelectric devices and in optical recording media, wherein X.sub.1 and X.sub.2 are independently selected from H, CN, COCH.sub.3, CO.sub.2 CH.sub.3, m=at least 5; X.sub.3 and X.sub.4 are independently selected from formula (IA), ##STR2## wherein Y is selected from COO, OCO, O, S, CHOH, CHF, CH.sub.2 ; Q=(CH.sub.2).sub.n wherein one or more non-adjacent methylenes may be replaced by O and n=1-20; Z is selected from O, S, single covalent bond, COO, OCO; when Y is CH2 then n may also be O; formula (A) ##STR3## represents any mesogenic group; X3 and X.sub.4 are also independently selected from H, OH, OCOR.sup.1, COOH, CO.sub.2 R.sup.1 (CH.sub.2).sub.p OH, (CH.sub.2).sub.p CO.sub.2 H, --(CH.sub.2).sub.p OR.sup.1 or --(CH.sub.2).sub.p CO.sub.2 R.sup.1 and p=1-20, R.sup.1 =H or C.sub.1=16 alkyl, when R.sup.1 =C.sub.2-16 alkyl the terminal Ch.sub.

Abstract: A liquid crystal device is provided with a pair of substrates (12, 16) containing a liquid crystal material (22). A wall structure comprising, for example, a plurality of walls (14) is provided between the two substrates. The wall structure provides mechanical strength to the device and resistance to flow of liquid crystal material which can cause deterioration in the device performance. The walls may extend in two mutually different directions (FIG. 8, 40) to provide mechanical strength and resistance to flow in two directions while the device can still be readily filled. The device is particularly applicable to a ferroelectric liquid crystal device.

Abstract: Liquid crystal polymer materials used in liquid crystal devices, piezoelectric devices, pyroelectric devices and recording media are described.

Abstract: Liquid crystal phases containing components of the formulae I and III have an acceptable combination of threshold steepness, viewing angle and temperature dependence at a low threshold voltage.