Abstract: A thermochromic fabric utilizing cholesteric liquid crystals includes a fabric material or garment formed therefrom. The liquid crystal material is patterned with a plurality of different liquid crystal formulations, whereby each formulation has high thermal sensitivity over a narrow temperature range. As a result, the aggregate pattern of liquid crystal material formed on the thermochromic fabric allows the thermochromic fabric to have high thermal sensitivity over a broad temperature range. As such, the fabric or garment may be worn on specific body parts of a patient, such as his or her feet, to assist in making a medical diagnosis.

Abstract: A piezoelectric device includes a fiber mat comprising polymer fibers with ferroelectric particles embedded in the polymer fibers. The ferroelectric particles are oriented to generate a net polarization in the fiber mat. The ferroelectric particles may comprise barium titanate particles. The polymer fibers may comprise polylactic acid (PLA) fibers. The piezoelectric device may further include substrates sandwiching the fiber mat, and the fiber mat may be formed by electrospinning polymer fibers containing ferroelectric particles onto one of the substrates. The piezoelectric device may be a piezoelectric actuator configured to receive an input voltage applied across the fiber mat and to output a mechanical displacement in response to the voltage, or the piezoelectric device may be configured to output a voltage in response to a mechanical force applied to the fiber mat.

Abstract: A method of patterning an electrically-conductive film is performed by providing a flexible substrate that carries the electrically-conductive film thereon to form a combined layer. The combined layer is then bent about a radius of curvature, so as to impart a stress on the brittle conductive film along the axis of curvature of the curved surface. The application of the stress to the conductive film results in the formation of crack lines that are substantially perpendicular to the direction to which the substrate and conductive film are bent. The crack lines serve to define and electrically isolate conductive sections therebetween that can be utilized as electrodes and address lines in electronic devices.

Abstract: A thermochromic fabric utilizing cholesteric liquid crystals includes a fabric material or garment formed therefrom. The liquid crystal material is patterned with a plurality of different liquid crystal formulations, whereby each formulation has high thermal sensitivity over a narrow temperature range. As a result, the aggregate pattern of liquid crystal material formed on the thermochromic fabric allows the thermochromic fabric to have high thermal sensitivity over a broad temperature range. As such, the fabric or garment may be worn on specific body parts of a patient, such as his or her feet, to assist in making a medical diagnosis.

Abstract: A piezoelectric device includes a fiber mat comprising polymer fibers with ferroelectric particles embedded in the polymer fibers. The ferroelectric particles are oriented to generate a net polarization in the fiber mat. The ferroelectric particles may comprise barium titanate particles. The polymer fibers may comprise polylactic acid (PLA) fibers. The piezoelectric device may further include substrates sandwiching the fiber mat, and the fiber mat may be formed by electrospinning polymer fibers containing ferroelectric particles onto one of the substrates. The piezoelectric device may be a piezoelectric actuator configured to receive an input voltage applied across the fiber mat and to output a mechanical displacement in response to the voltage, or the piezoelectric device may be configured to output a voltage in response to a mechanical force applied to the fiber mat.

Abstract: The invention relates to flexible liquid crystal devices and methods, and the electrically conducting backplane of a liquid crystal display for example. A substrate is provided that supports components of a liquid crystal display including a liquid crystal layer that is electrically addressed to produce images. The substrate can be flexible or drapable. An electrode arrangement is formed on the substrate, which includes a plurality of small islands or zones of highly conductive material. The highly conductive islands or zones may be dimensioned to be smaller than the dimensions of the electrode pattern, and are electrically isolated from one another. The plurality of islands or zones are then connected in a predetermined pattern by a conducting polymer layer having a predetermined configuration to provide the desired electrode pattern.

Abstract: There are provided methods and systems for precisely controlling the surfactant concentration and character of ferroelectric nanoparticles in a ferroelectric liquid crystal dispersion. In an aspect, the invention provides an efficient FTIR technique to characterize the status and measure the distribution of the surfactant in ferroelectric particle dispersion. This allows for establishing a reproducible fabrication process for ferroelectric nanoparticle liquid crystal dispersions. The methods also maintain the nanoparticles ferroelectricity, which is provided by the addition of surfactant during a comminution process. The invention therefore optimizes both the milling time (to achieve small particle size and narrow size distribution) and surfactant concentration (to maintain the ferroelectricity during milling).

Abstract: A process for making a stimuli responsive liquid crystal-polymer composite fiber comprising mixing a liquid crystal, a polymer, and a solvent; processing the mixture in the presence of an electric potential across a collection distance; phase separating a polymer and said liquid crystal; and encapsulating said liquid crystal within said polymer. The fiber generally comprises a liquid crystal core and a polymer shell wherein the liquid crystal is responsive to chemical changes, thermal and mechanical effects, as well as electrical and magnetic fields. A liquid crystal containing fiber can be utilized as optical fibers, in textiles, and in optoelectronic devices.

Abstract: A new light modulating material using interconnected unidirectionally oriented microdomains of a liquid crystal, dispersed in a stressed polymer structure, is provided. The light modulating material is prepared by dissolving the liquid crystal in an uncured monomer and then curing the monomer so that the polymer forms a well-developed interpenetrating structure of polymer chains or sheets that is uniformly dispersed through the film. When the film is subjected to stress deformation the liquid crystal undergoes a change in its unidirectional orientation. The concentration of the polymer is high enough to hold the shear stress, but is as low as possible to provide the highest switch of the phase retardation when an electric field is applied. The new materials are optically transparent and provide phase modulation of the incident light opposed to the low driving voltage, linear electro-optical response, and absence of hysteresis.

Abstract: There are provided methods and systems for precisely controlling the surfactant concentration and character of ferroelectric nanoparticles in a ferroelectric liquid crystal dispersion. In an aspect, the invention provides an efficient FTIR technique to characterize the status and measure the distribution of the surfactant in ferroelectric particle dispersion. This allows for establishing a reproducible fabrication process for ferroelectric nanoparticle liquid crystal dispersions. The methods also maintain the nanoparticles ferroelectricity, which is provided by the addition of surfactant during a comminution process. The invention therefore optimizes both the milling time (to achieve small particle size and narrow size distribution) and surfactant concentration (to maintain the ferroelectricity during milling).

Abstract: A process for making a stimuli responsive liquid crystal-polymer composite fiber comprising mixing a liquid crystal, a polymer, and a solvent; processing the mixture in the presence of an electric potential across a collection distance; phase separating a polymer and said liquid crystal; and encapsulating said liquid crystal within said polymer. The fiber generally comprises a liquid crystal core and a polymer shell wherein the liquid crystal is responsive to chemical changes, thermal and mechanical effects, as well as electrical and magnetic fields. A liquid crystal containing fiber can be utilized as optical fibers, in textiles, and in optoelectronic devices.

Abstract: The invention provides a liquid crystal (LC) composite, a LC cell, a LC device, and a method thereof. The LC composite comprises (i) a liquid crystal material, and (ii) a copolymer polymerized from LC monomers and non-LC-monomers; and the LC composite is mechanically stressed/sheared. The invention exhibits numerous merits such as high transmittance in visible and IR range, hysteresis free, and a simple fabrication process; and may be utilized in LC device applications such as adaptive optics e.g. beam steering devices and fast tip-tilt wavefront correctors; and general optical applications such as eye wears, compact cameras and compact telescopes.

Abstract: The invention provides a film comprising a polymer dispersed liquid crystal (PDLC) which exists independently from a substrate, i.e. a substrate-free PDLC; a fiber, a fabric, and a device thereof; and methods thereof. In an embodiment, a mixture comprising liquid crystal and monomers floats and is spread over a liquid base, before polymerization the mixture into a layer of polymer matrix dispersed with liquid crystal domains. The invention exhibits numerous technical merits such as improved transmittance, enhanced brightness, easier manufacturability, more flexible manufacturability, better cost-effectiveness, enhanced electro-optical performance, and improved device uniformity, among others.

Abstract: The invention relates to flexible liquid crystal devices and methods, and the electrically conducting backplane of a liquid crystal display for example. A substrate is provided that supports components of a liquid crystal display including a liquid crystal layer that is electrically addressed to produce images. The substrate can be flexible or drapable. An electrode arrangement is formed on the substrate, which includes a plurality of small islands or zones of highly conductive material. The highly conductive islands or zones may be dimensioned to be smaller than the dimensions of the electrode pattern, and are electrically isolated from one another. The plurality of islands or zones are then connected in a predetermined pattern by a conducting polymer layer having a predetermined configuration to provide the desired electrode pattern.

Abstract: This disclosure outlines a new method of modifying the properties of existing liquid crystals by doping them with ferroelectric micro- and nanoparticles. We show that this approach, in contrast to the traditional time consuming and expensive chemical synthetic methods, enriches and enhances the electro-optical performance of many liquid crystal materials. We demonstrate that by changing the concentration and type of ferroelectric particles the physical properties of the nematic, smectic, and cholesteric liquid crystal materials can be changed, including the dielectric constants, the birefringence, the phase transition temperatures, and even the order parameter. We also demonstrate the performance of these new materials in various devices, including displays, light modulators, and beam steering devices.

Abstract: A new light modulating material using interconnected unidirectionally oriented microdomains of a liquid crystal, dispersed in a stressed polymer structure, is provided. The light modulating material is prepared by dissolving the liquid crystal in an uncured monomer and then curing the monomer so that the polymer forms a well-developed interpenetrating structure of polymer chains or sheets that is uniformly dispersed through the film. When the film is subjected to stress deformation the liquid crystal undergoes a change in its unidirectional orientation. The concentration of the polymer is high enough to hold the shear stress, but is as low as possible to provide the highest switch of the phase retardation when an electric field is applied. The new materials are optically transparent and provide phase modulation of the incident light opposed to the low driving voltage, linear electro-optical response, and absence of hysteresis.

Abstract: A new light modulating material using interconnected unidirectionally oriented microdomains of a liquid crystal, dispersed in a stressed polymer structure, is provided. The light modulating material is prepared by dissolving the liquid crystal in an uncured monomer and then curing the monomer so that the polymer forms a well-developed interpenetrating structure of polymer chains or sheets that is uniformly dispersed through the film. When the film is subjected to stress deformation the liquid crystal undergoes a change in its unidirectional orientation. The concentration of the polymer is high enough to hold the shear stress, but is as low as possible to provide the highest switch of the phase retardation when an electric field is applied. The new materials are optically transparent and provide phase modulation of the incident light opposed to the low driving voltage, linear electro-optical response, and absence of hysteresis.

Abstract: Fluidic flow is directed in a capillary or channel in a miniaturized separation or microfluidic device by the addition of liquid crystals to the fluid filling the channel. The liquid crystal medium undergoes changes in morphology upon the addition of external stimuli (magnetic and/or electric field and temperature). Under appropriate conditions this externally triggered change in liquid crystal produces a change in viscosity. This triggered change in viscosity directs fluid flow in multiple path channels and/or capillaries and therefore serves as a means of directing and controlling fluid flow within a capillary or channel in a miniaturized separation or microfluidic device.

Abstract: A new light modulating material using unidirectionally oriented micro-domains of liquid crystal separated by polymer chains is provided. Liquid crystal/polymer films are produced by a one step production process involving a photopolymerizable monomer mixed with a liquid crystal then exposed to UV light. In one embodiment, force deformations are applied to the films resulting in diffraction efficiencies of more than 95%. In another embodiment, applying a planar force to a thick film that produced a 2 ?m shift of phase retardation in several hundred microseconds when an appropriate field is applied. Use of this invention provides fast response time and a low required driving voltage. The new cell can be used as spatial light modulators for manufacturing information displays, electro-optical devices, telecommunications system, optical data processing, adaptive optics applications, color projection displays and switchable micro-lens optics.

Abstract: A new light modulating material using unidirectionally oriented micro-domains of liquid crystal separated by polymer chains is provided. Liquid crystal/polymer films are produced by a one step production process involving a photopolymerizable monomer mixed with a liquid crystal then exposed to UV light. In one embodiment, force deformations are applied to the films resulting in diffraction efficiencies of more than 95%. In another embodiment, applying a planar force to a thick film that produced a 2 &mgr;m shift of phase retardation in several hundred microseconds when an appropriate field is applied. Use of this invention provides fast response time and a low required driving voltage. The new cell can be used as spatial light modulators for manufacturing information displays, electro-optical devices, telecommunications system, optical data processing, adaptive optics applications, color projection displays and switchable micro-lens optics.