Abstract: A method of aligning a chiral nematic liquid crystal, the method comprising depositing a first chiral nematic liquid crystal onto a first substrate, positioning a second substrate on top of the liquid crystal to form an initial layer structure and then applying rolling pressure to at least one of the substrates of the initial layer structure to create a final layer structure in which the first chiral nematic liquid crystal is aligned with a helical axis substantially perpendicular to a local plane of the first substrate. Aspects of the invention provide optical filter materials for laser protection applications, LED emission filtering and lighting, augmented reality display coatings.

Abstract: A method of aligning a chiral nematic liquid crystal (103), the method comprising depositing a first chiral nematic liquid crystal (103) onto a first substrate (102), positioning a second substrate (104) on top of the liquid crystal (103) to form an initial layer structure and then applying rolling pressure to at least one of the substrates (102, 104) of the initial layer structure to create a final layer structure in which the first chiral nematic liquid crystal (103) is aligned with a helical axis substantially perpendicular to a local plane of the first substrate (102). Aspects of the invention provide optical filter materials for laser protection applications, LED emission filtering and lighting, augmented reality display coatings.

Abstract: A method of aligning a chiral nematic liquid crystal (103), the method comprising depositing a first chiral nematic liquid crystal (103) onto a first substrate (102), positioning a second substrate (104) on top of the liquid crystal (103) to form an initial layer structure and then applying rolling pressure to at least one of the substrates (102, 104) of the initial layer structure to create a final layer structure in which the first chiral nematic liquid crystal (103) is aligned with a helical axis substantially perpendicular to a local plane of the first substrate (102). Aspects of the invention provide optical filter materials for laser protection applications, LED emission filtering and lighting, augmented reality display coatings.

Abstract: A method of manufacturing a security feature for identifying objects or documents of value. The method may include the steps of encoding information in a pattern; and ink jet printing a chiral nematic liquid crystal material from a reservoir using a print head on to a substrate in the pattern. Thus, the method forms a patterned array of chiral nematic liquid crystal material deposits. The print head, or the reservoir, or both, may be heated to a temperature above the clearing point of the chiral nematic liquid crystal material. The chiral axes of the chiral nematic liquid crystal material deposits may be aligned substantially perpendicular to the substrate such that a predetermined portion of the electromagnetic spectrum is selectively reflected over other regions of the electromagnetic spectrum by the chiral nematic liquid crystal material deposits.

Abstract: A method of manufacturing a security feature for identifying objects or documents of value. The method may include the steps of encoding information in a pattern; and ink jet printing a chiral nematic liquid crystal material from a reservoir using a print head on to a substrate in the pattern. Thus, the method forms a patterned array of chiral nematic liquid crystal material deposits. The print head, or the reservoir, or both, may be heated to a temperature above the clearing point of the chiral nematic liquid crystal material. The chiral axes of the chiral nematic liquid crystal material deposits may be aligned substantially perpendicular to the substrate such that a predetermined portion of the electromagnetic spectrum is selectively reflected over other regions of the electromagnetic spectrum by the chiral nematic liquid crystal material deposits.

Abstract: A photonic device is manufactured by: (i) providing (e.g. by inkjet printing) an aliquot of a liquid crystal (LC) material; and (ii) depositing the aliquot onto the surface of a flowable material layer to form a liquid crystal deposit, the flowable material and the LC material being substantially immiscible. The liquid crystal deposit adopts a deformed shape relative to the shape of the aliquot due to interaction with the flowable material layer. This promotes alignment of the LC material. Incorporation of a laser dye allows the photonic device to function as a laser, which can be operated above or below threshold depending on the circumstances. The photonic device can also be used as a passive device based on the photonic bandgap of the aligned LC material.

Abstract: A photonic device is manufactured by: (i) providing (e.g. by inkjet printing) an aliquot of a liquid crystal (LC) material; and (ii) depositing the aliquot onto the surface of a flowable material layer to form a liquid crystal deposit, the flowable material and the LC material being substantially immiscible. The liquid crystal deposit adopts a deformed shape relative to the shape of the aliquot due to interaction with the flowable material layer. This promotes alignment of the LC material. Incorporation of a laser dye allows the photonic device to function as a laser, which can be operated above or below threshold depending on the circumstances. The photonic device can also be used as a passive device based on the photonic bandgap of the aligned LC material.

Abstract: This invention generally relates to a liquid crystal device, and more particularly to such a device in the form of a liquid crystal cell such as for a display device, and further relates to a display device having the liquid crystal device, an optical waveguide device comprising the liquid crystal device, a Variable Optical Attenuator comprising the liquid crystal device, an optical switch comprising the liquid crystal device, a method of controlling transmission of polarised light, and to a further liquid crystal device. A liquid crystal device for controlling transmission of polarised light, comprising: chiral nematic liquid crystal having a helical arrangement of liquid crystal molecules in the absence of an electric field; and at least two electrodes for applying an electric field having a component normal to the helical axis of the chiral nematic liquid crystal, wherein the chiral nematic liquid crystal has negative dielectric anisotropy.