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THIEF RIVER FALLS, Minn., Sept. 28, 2017 /PRNewswire/ -- A selection of Displaytech's LCD display modules and integrated TFT driver boards is currently available for immediate shipment worldwide through Digi-Key Electronics, a global electronic components distributor, as the result of a...


Martinez-Perdiguero J.,University of the Basque Country | Zhang Y.,DisplayTech | Zhang Y.,Micron Technology Inc. | Walker C.,DisplayTech | And 7 more authors.
Journal of Materials Chemistry | Year: 2010

This contribution describes the analysis of experimental results on second harmonic generation (SHG) in a novel laterally azo-bridged H-shaped ferroelectric liquid crystal (FLC) 2, incorporating a disperse red 1 (DR-1) chromophore along the FLC polar axis, and its two mixtures with a laterally azo-bridged H-shaped FLC host 1, incorporating an azobenzene chromophore. The largest dij coefficient at the fundamental wavelength of λ = 1.6 μm is d22 = 4.5 pm/V, the coefficient along the polar axis that is optimized from the viewpoint of the chemical design of NLO FLC molecules. A linear dependence of d22 on the mole fractions of 2 in mixtures has been found, indicating that i) both 1 and 2 have a similar degree of polar order, and ii) dipole-dipole interaction in the DR-1 chromophore of 2 is not strong due to low chromophore density. This work highlights the importance of synthetic tailorability of FLC materials with extra functionality to second-order nonlinear optics applications. © The Royal Society of Chemistry 2010.


Reznikov M.,Kent State University | Bos P.J.,Kent State University | O'Callaghan M.J.,DisplayTech
Journal of Applied Physics | Year: 2010

SiOx alignment layers have been shown to allow defect-free SmC devices with near optimum bistable orientation of the director. In this paper we investigate the effect of the thickness of this type of alignment layer on the required amplitude of an applied voltage pulse to cause bistable switching. The results of an experimental investigation and simple model are presented. We find that for thicker layers, the amplitude is controlled by the voltage drop across the alignment layers and by the effect of polar interactions between the liquid crystal (LC) and the alignment layers. For thin alignment layers the amplitude is weakly dependent on the details of the alignment layer, being more strongly influenced by the properties of the LC material. © 2010 American Institute of Physics.


Reznikov M.,Kent State University | Lopatina L.M.,Kent State University | O'Callaghan M.J.,DisplayTech | Bos P.J.,Kent State University
Journal of Applied Physics | Year: 2011

The effect of surface alignment on the achievement of analog ("V"-shaped) electric field control of director rotation in SmC*liquid crystal devices is investigated experimentally and through numerical modeling. Ferroelectric SmC*liquid crystals are intrinsically analog and thresholdless, i.e. the director can be rotated freely around the tilt cone. Whether or not a SmC*liquid crystal cell exhibits thresholdless switching depends strongly on the influence of the cell's alignment layers, on the magnitude of the liquid crystal's spontaneous polarization, and on whether smectic layers adopt a bookshelf or chevron configuration. To study the effect of the surface alignment layers, we have exploited a technique for the vertical (bookshelf) alignment of the smectic layers that does not depend on surface anisotropy. The alignment technique allows an experimental study of the influence of surfaces spanning a wide range of pretilt angles, azimuthal and zenithal anchoring energies. This technique is used to study the effect of surfaces on the threshold behavior of director rotation in SmC*materials under the influence of an electric field. The alignment technique also allowed us to use a high-PS liquid crystal material having an I-A-C phase sequence and reduced layer shrinkage thought to be well suited to thresholdless switching. We show that the alignment layer has a strong effect, and that excellent analog response can be achieved for the case of alignment layers which promote homeotropic director orientation. We further model and discuss the potential effect of a thin layer of nematic at the surface and the possibility of gliding of the easy axis during switching. © 2011 American Institute of Physics.


Zhang Y.,DisplayTech | Baumeister U.,Martin Luther University of Halle Wittenberg | Tschierske C.,Martin Luther University of Halle Wittenberg | O'Callaghan M.J.,DisplayTech | Walker C.,DisplayTech
Chemistry of Materials | Year: 2010

New organic-inorganic hybrid materials that combine a bent π-conjugated aromatic core with one linear or branched carbosilane unit have been synthesized and investigated, with respect to their self-assembly in liquid crystalline (LC) phases, by means of polarizing microscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and electro-optical techniques. Most of these achiral compounds show spontaneous symmetry breaking into chiral superstructures that represent conglomerates with macroscopic domains of opposite handedness. These fluid chiral superstructures can be frozen into the glassy state and, for one of the compounds, chirality was switched under the application of a special waveform of an applied external electric field between two enantiomeric states. This flipping of supramolecular chirality occurs between oppositely tilted structures, which represents a new mode of chirality switching. Besides spontaneous chirality, these materials show polar order, leading to ferroelectric (FE) and antiferroelectric (AF) switching modes. For one compound with a highly branched carbosilane unit, a temperature-, voltage-, and frequency-dependent reversible transition from AF switching with inversion of chirality to FE switching with retention of chirality was observed. Models were developed to explain the experimental observations, based on enthalpic and entropic contributions of distinct supermolecular arrangements in these soft matter systems. © 2010 American Chemical Society.


Polydimethylsiloxane (PDMS)-based organic-inorganic hybrids have been studied because of their high dielectric strength, heat resistivity, and flexibility. In this study, we fabricated Al2O3 coatings on metal substrates with sufficient electrical insulation, heat conductivity, and thermal stability by electrophoretic deposition (EPD) using PDMS-based hybrid binders. The scratch hardness, thermal conductivity, and electrical breakdown strength of the Al2O3 coating before and after heat treatment at 300 °C for 500 h were 2.0 N, 3.1 W/mK, and 60 kV/mm, respectively. These results demonstrate the usefulness of EPD using PDMS-based hybrid binders for fabricating flexible heat dissipative substrates used in high-temperature environments. Copyright © 2015 Taylor & Francis Group, LLC.


Grant
Agency: National Science Foundation | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 100.00K | Year: 2009

This Small Business Innovation Research Phase I project aims to examine the feasibility of developing a new class of bent-core NLO ferroelectric liquid crystals (FLCs) capable of advanced, low cost, laser light sources for displays on the basis of their strong second harmonic generation (SHG). These materials will also have large electro-optic (EO) coefficients and can be readily integrated with silicon VLSI, enabling their use in high-bandwidth chip-to-chip data transfer, optical long-haul, and fiber-to-the-home telecommunications. This SBIR Phase I project will advance the scientific and technological understanding of a new class of bent-core NLO ferroelectric liquid crystals. This innovation will enable advanced optoelectronic products across multiple markets, including laser illuminators for projection display, high-speed integrated EO modulators (e.g. >100GHz), switches for optical interconnects and telecommunications, and sensors and devices for optical information processing. This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).


Trademark
DisplayTech | Date: 2015-05-25

3D spectacles; Batteries, electric; Battery chargers; Electric navigational instruments; Notebook computers; Portable media players; Portable telephones; Smartphones; Tablet computer; Telephone apparatus; Video telephones; Wireless controllers to monitor and control the functioning of other electronic devices.


Trademark
DisplayTech | Date: 2014-08-01

3D spectacles; Batteries, electric; Battery chargers; Electric navigational instruments; Notebook computers; Portable media players; Portable telephones; Smartphones; Tablet computer; Telephone apparatus; Video telephones; Wireless controllers to monitor and control the functioning of other electronic devices.

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