Abstract: The invention relates to a polymer for use as a surface-director alignment layer in a liquid crystal device, the polymer comprising a polymeric backbone and side-chains attached thereto, wherein the polymeric backbone lacks directly coupled ring structures, and each side-chain of at least some of the side-chains comprises at least two unsubstituted and/or substituted phenyls coupled via a coupling selected from the group consisting of a carbon-carbon single bond (—), a carbon-carbon double bond containing unit (—CH?CH—), a carbon-carbon triple bond containing unit (—C?C—), a methylene ether unit (—CH2O—), an ethylene ether unit (—CH2CH2O—), an ester unit (—COO—) and an azo unit (—N?N—), exhibits a permanent and/or induced dipole moment that in ordered phase provides dielectric anisotropy, and is attached to the polymeric backbone via at least two spacing atoms.

Abstract: In a preparation method, a chiral or cholesteric liquid crystal, a photoreactive monomer, and a photoinitiator are disposed in a liquid crystal cell. A principal surface of the liquid crystal cell is illuminated with ultraviolet light selected to have a non-uniform ultraviolet light intensity profile in the liquid crystal cell. The illuminating cooperates with the photoinitiator to polymerize at least a portion of the photoreactive monomer near the principal surface to generate a polymer network having a density corresponding to the non-uniform ultraviolet light intensity profile. The polymer network biases the liquid crystal toward a selected helical alignment direction. In some embodiments, the illuminating includes illuminating with first and second ultraviolet light intensity profiles to produce surface and volume polymer network components.

Abstract: An electro-optic device includes a liquid crystal cell (10, 10?) and at least one electrode (40, 42, 40?, 42?) arranged to selectively electrically bias the liquid crystal cell (10, 10?). A chiral or cholesteric liquid crystal (30, 30?) is disposed in the liquid crystal cell (10, 10?). The liquid crystal (10, 10?) has an optic axis substantially along a selected optic axis direction in the absence of an electrical bias. A polymeric network (32, 32?, 72) is disposed at an inside surface of the liquid crystal cell (10, 10?). The polymeric network (32, 32?, 72) extends partway into the liquid crystal cell (10, 10?) leaving at least a portion of the liquid crystal cell (10, 10?) substantially free of the polymeric network (32, 32?, 72).

Abstract: An electro-optic device includes a liquid crystal cell (10, 10?) and at least one electrode (40, 42, 40?, 42?) arranged to selectively electrically bias the liquid crystal cell (10, 10?). A chiral or cholesteric liquid crystal (30, 30?) is disposed in the liquid crystal cell (10, 10?). The liquid crystal (10, 10?) has an optic axis substantially along a selected optic axis direction in the absence of an electrical bias. A polymeric network (32, 32?, 72) is disposed at an inside surface of the liquid crystal cell (10, 10?). The polymeric network (32, 32?, 72) extends partway into the liquid crystal cell (10, 10?) leaving at least a portion of the liquid crystal cell (10, 10?) substantially free of the polymeric network (32, 32?, 72).

Abstract: A fast and highly practical photoinduced switching liquid crystal device is provided.

Abstract: An electrooptic device (2), and the methods for manufacturing, including a liquid crystal material (12) disposed between electroded flat glass or polymer substrates (4, 20) which have been precoated with a e.g. a chiral smectic surface layer (10, 14) in such way that the surface layer is able to mediate switching of the liquid crystal (12) between different optical states. The chiral smectic surface layer can be a polymer, oligomer or monomer liquid crystal with paraelectric, ferroelectric, ferrielectric or antiferroelectric response, which is insoluble in the liquid crystal used for the bulk (12) between the electroded substrates (4, 20). the switchable surface director enforces a certain orientation of the optic axis in the bulk liquid crystal (12), which can be a conventional non-chiral or chiral nematic or smectic in a twisted or non-twisted configuration.

Abstract: An electrooptic device (2), and the methods for manufacturing, including a liquid crystal material (12) disposed between electroded flat glass or polymer substrates (4, 20) which have been precoated with a e.g. a chiral smectic surface layer (10, 14) in such way that the surface layer is able to mediate switching of the liquid crystal (12) between different optical states. The chiral smectic surface layer can be a polymer, oligomer or monomer liquid crystal with paraelectric, ferroelectric, ferrielectric or antiferroelectric response, which is insoluble in the liquid crystal used for the bulk (12) between the electroded substrates (4, 20). the switchable surface director enforces a certain orientation of the optic axis in the bulk liquid crystal (12), which can be a conventional non-chiral or chiral nematic or smectic in a twisted or non-twisted configuration.

Abstract: A device for influencing light has a polarizer, a ferroelectric or electroclinic response type liquid crystal halfwave plate whose liquid crystals are in the smectic phase with bookshelf geometry and have molecular axes which are rotatable around a first direction corresponding to the direction of incoming light in response to an electric field applied across the electrodes on either side of the halfwave plate, a quarter wave retarder plate, and a mirror. The polarizer, plates and mirror are arranged such that incoming light is passed from the polarizer through the liquid crystal plate and the retarder plate, and is reflected by the mirror in a second direction opposite to the first direction back through the retarder and the liquid crystal plate so as to provide a reflected polarized light plane to the polarizer.

Abstract: A device for influencing light has a polarizer, a ferroelectric or electroclinic response type liquid crystal halfwave plate whose liquid crystals are in the smectic phase with bookshelf geometry and have molecular axes which are rotatable around a first direction corresponding to the direction of incoming light in response to an electric field applied across the electrodes on either side of the halfwave plate, a quarter wave retarder plate, and a mirror. The polarizer, plates and mirror are arranged such that incoming light is passed from the polarizer through the liquid crystal plate and the retarder plate, and is reflected by the mirror in a second direction opposite to the first direction back through the retarder and the liquid crystal plate so as to provide a reflected polarized light plane to the polarizer.

Abstract: An electro-optical device including a chiral nematic liquid crystal disposed between flat plates treated to weakly enforce molecular orientation along one preferred direction parallel to the plates. The plates are spaced by a distance small compared to the pitch of the helix typical in a bulk of the material, or the helix compensated by additives to ensure the equivalent situation. By an externally applied electric field the liquid crystal molecular orientation is rotated in a plane parallel to the plates away from the preferred orientation an angle the sign and size of which depends on the sign and magnitude of the field. The optical axis of the liquid crystal, oriented along the molecular orientation, is thus controlled by the external electric field in such a way as to make a linear light valve or other electro-optical device.