A double layer liquid crystal device comprises a first and a second layer with orthogonal or crossed alignment of the liquid crystal phase of the two layers, in which the first and second layer have first and second alignment aids comprised of a polymerized or polymerizable molecular compound. The layers are aligned by UV photoalignment and vertical self-alignment by the aid of suitable additives.

An optical component and a electro optical devices comprising the optical component. Further, a cholesteric polymerizable liquid crystalline (LC) material, preferably utilized in an optical component in accordance with the present invention, a process for the production of the cholesteric polymerizable LC material, a process to convert the cholesteric polymerizable material into a polymer film, a polymer film obtainable from the cholesteric polymerizable LC material, and the use of the polymer films in an optical component or device comprising a polymer film.

A first object of the present invention is to provide a liquid crystal composition capable of forming a reflective layer having excellent diffuse reflectivity. A second object of the present invention is to provide a method for producing a reflective layer having excellent diffuse reflectivity and a reflective layer having excellent diffuse reflectivity. A third object of the present invention is to provide a cured product and an optically anisotropic body, each of which is formed of the liquid crystal composition. The present invention relates to a liquid crystal composition including a liquid crystal compound; a chiral agent A whose helical twisting power is reduced upon light irradiation; and a chiral agent B which induces a helix in a direction opposite to that of the chiral agent A, in which the liquid crystal compound is cholesterically aligned in the direction of the helix induced by the chiral agent B in a case where the liquid crystal compound is aligned into a cholesteric liquid crystalline phase state.

Provided are a cholesteric liquid crystal layer having an excellent reflection anisotropy, a low haze, and a high circular polarization degree of reflected light, and a method for producing the same. In addition, provided are a laminate, an optically anisotropic body, and a reflective film, each of which including the cholesteric liquid crystal layer. A cholesteric liquid crystal layer formed using a liquid crystal compound, in which, in at least one main plane out of a pair of main planes of the cholesteric liquid crystal layer, a direction of a molecular axis of the liquid crystal compound changes while continually rotating along at least one in-plane direction, the molecular axis of the liquid crystal compound is tilted with respect to the main plane of the cholesteric liquid crystal layer, and an arrangement direction of bright portions and dark portions derived from the cholesteric liquid crystalline phase, as observed under a scanning electron microscope in a cross section perpendicular to the main plane, is tilted with respect to the main plane of the cholesteric liquid crystal layer.

Disclosed herein is a light emitting device and method of manufacturing such a device comprised of a series of photopolymerizable, chiral liquid crystalline layers that can be solvent cast on a substrate. The mixture of chiral materials in each successive layer may be blended in such a way that each layer has the same chiral pitch. Further the chiral materials in each layer may also be blended so that the ordinary and extraordinary refractive indices in each layer match the other layers such that the complete assembly of layers will optically function as a single relatively thick layer of chiral liquid crystal. The chiral nematic material in each layer can spontaneously adopt a helical structure with a helical pitch. The light emitting layers of the light emitting device can further comprise electroluminescent material that emits light into the band edge light propagation modes of the photonic crystal.

The invention relates to a liquid-crystalline medium, preferably having a nematic phase and dielectric anisotropy of 0.5 or more, which comprises one or more compounds of formula YX ##STR00001## in which
the parameters have the meanings given in the text,
to the use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, to displays of this type which contain a liquid-crystalline medium of this type, and to the use of the compounds of formula YX for the improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.

An optical device (20) includes an electro-optical layer, including a liquid crystal material (24) with a heliconical structure having a pitch that is less than 250 nm and is modifiable by an electric field. An array of excitation electrodes (28) extends over the electro-optical layer. Control circuitry (23) is coupled to apply control voltage waveforms to the excitation electrodes and is configured to modify the control voltage waveforms so as to locally modify a molecule director angle of the heliconical structure and thus to generate a specified phase modulation profile in the electro-optical layer.

The present invention relates to a liquid-crystal (LC) medium comprising polymerizable compounds, to its use for optical, electro-optical and electronic purposes, in particular in LC displays, especially in LC displays of the PSA (polymer sustained alignment) or SA (self-aligning) mode, to an LC display of the PSA or SA mode comprising the LC medium, and to a process of manufacturing the LC display using the LC medium, especially an energy-saving LC display and energy-saving LC display production process.

Liquid-crystalline media having one or more compounds of formula C ##STR00001##
and high-frequency components containing 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).

The present invention relates to liquid-crystalline media comprising one or more mesogenic compounds of formula I as set forth hereinafter, wherein the one or more compounds of formula I are contained in the medium in an amount, based on the overall contents of the medium, of at least 15% by weight. The present invention further relates to a switching layer, a switching element and a window element containing the liquid-crystalline medium.