The disclosure discusses chiral dopants for liquid-crystalline materials. Chiral dopants can be bioreachable compounds, i.e. compounds produced from microbes through fermentation. Chiral dopants can also include bioreachable materials that are further modified by chemical synthetic steps. Chiral dopants as discussed herein can include biomolecules such as glycyrrhetinic acid (1), S-narigenin (2), shikimic acid (3), alpha-phellandrene (4), betulin (5), malic acid (6), valencene (7), or nootkatone (8), and any stereoisomers or chemically modified derivatives thereof. The disclosure further shows optical properties of such compounds in a liquid-crystalline material.

The present invention relates to liquid-crystalline media comprising one or more pleochroic compounds, and one or more compounds selected from the group of compounds of formulae I, II and III, ##STR00001##
in which the groups have the meanings as set forth in claim 1,
and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

A liquid crystal mixture and a temperature-responsive infrared reflection device made by using the liquid crystal mixture containing potassium laurate. Infrared light can pass through the device within a non-working temperature range, and a chiral dopant enables potassium laurate to form a cholesteric phase within a working temperature range. The birefringence value of the potassium laurate gradually increases with the increase of temperature between 12.5° C. and 26° C., so that the infrared reflection bandwidth of the device constantly increases. The birefringence value of the potassium laurate gradually decreases with the increase of temperature between 26° C. and 54.5° C., so that the infrared reflection bandwidth of the device constantly decreases. The infrared reflection bandwidth of the infrared reflection device can vary with temperature by adjusting the proportions of the ingredients of the liquid crystal mixture containing potassium laurate.

Chiral polymer microspheres have a porous structure of a concentric multi-shell structure. Each layer of the multi-shell structure is optically and structurally anisotropic. The optical axes of adjacent layers have a sequential slight twist. All layers of the multi-shell structure generate a helix configuration and the chiral polymer microspheres are optically active. A method for preparing the chiral polymer microspheres, includes: forming a homogeneous liquid crystal mixture; dispersing the liquid crystal mixture into a continuous phase to form liquid crystal droplets through an emulsification process; polymerizing the reactive liquid crystal to form intermediate microspheres; and removing the one non-reactive liquid crystal and the chiral additive to form the chiral polymer microspheres. The chiral polymer microspheres have a porous structure and a swelling ability, and can be used as the stationary phase in chiral chromatograph, improving separation efficiency.

The present invention relates to an LC medium comprising and a liquid-crystalline host consisting of an LC component H) comprising one or more mesogenic or liquid-crystalline compounds and an optically active component D) and optionally a polymerizable component P) comprising one or more polymerizable compounds; and to the use of the polymerizable compounds and LC media for optical, electro-optical and electronic purposes, in particular in LC displays, especially in LC displays of the polymer sustained alignment type.

Liquid-crystalline media containing one or more mesogenic compounds, one or more chiral compounds, and one or more polymerizable mesogenic compounds, wherein the media exhibit a pitch of 0.55 μm or more and a clearing point of 80° C. or more and wherein the one or more polymerizable mesogenic compounds are contained in an amount, based on the overall contents of the media, of 5% by weight or less, are suitable as modulation materials. Such modulation materials can be used in switching layers and window elements.

The present invention relates to a liquid crystal (LC) medium comprising a compound of formula I

##STR00001## and one or more compounds selected from the group of compounds of the formulae IIA, IIB, IIC and IID,

##STR00002## as defined in claim 1, and to the use thereof for optical, electro-optical and electronic purposes, in particular in LC displays, especially in IPS, FFS, VA or PS-VA displays.

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.

A device includes a polymer stabilized blue phase liquid crystal (“PS-BPLC”) layer. The device also includes an alignment structure coupled with the PS-BPLC layer. LC molecules disposed in contact with the alignment structure are configured to have a spatially varying in-plane orientation pattern that is at least partially defined by the alignment structure. The PS-BPLC layer is configured to forwardly deflect a polarized light having a predetermined handedness, and transmit a polarized light having a handedness that is orthogonal to the predetermined handedness.

A device includes a polymer stabilized blue phase liquid crystal (“PS-BPLC”) layer. The device also includes an alignment structure coupled with the PS-BPLC layer. LC molecules disposed in contact with the alignment structure are configured to have a spatially varying in-plane orientation pattern that is at least partially defined by the alignment structure. The PS-BPLC layer is configured to forwardly deflect a polarized light having a predetermined handedness, and transmit a polarized light having a handedness that is orthogonal to the predetermined handedness.