Kent State University

Antal Jakli

John Ernest Harden, Jr

Peter Palffy-Muhoray

James T Gleeson

Samuel Sprunt

Alfred Saupe

Bahman Taheri

Liang-Chy Chien

John L West

Gerd Heppke

Quan Li

Chenrun Feng

Ebru Aylin Buyuktanir

Peter Palinkás, Legal Representative

Jason Morvan

Andrea Palinkás, Legal Representative

Zoltan Varga

Lanfang Li

Elizabeth Mann

Daniel Krüerke

Hans Sawade

Stefanie Taushanoff

Piotr Popov

Mátyás Molnár

Attila Bóta

Erika Kalman

A doped ferroelectric nematic liquid crystal includes a chirality-induced stabilization of the polar nematic order, improved relaxation time for electro-optical switching, and selective reflection in the visible wavelength that is reversibly tunable. The ferroelectric nematic liquid crystal is doped with a chiral dopant selected from benzoic acid, 4-hexyl-,4-[[(1-methylheptyl)oxy]carbonyl]phenyl ester (ZLI811) and BDH1281.

Electrically tunable reflection color of chiral ferroelectric nematic liquid crystals

Systems and methods for detection of an amphiphile at a liquid crystal interface include the production of circular polarized light. A systemfor detecting an amphiphile at a liquid crystal interface comprises a source of white collimated light. A circular polarizer is included for circularly polarizing incoming white light. Polarized white light passes through to an LC grid including a suspended LC film and a solution in contact with the LC grid at a surface. A spectrophotometer optically detects the presence of an amphiphile at the surface by determining a change in birefringence exhibited by the suspended LC film. A method for detecting amphiphiles at a liquid crystal water interface comprises shining collimated white light on an LC cell including an LC film, polarizing the white light with a circular polarizer, adding an amphiphile to a solution in contact with the LC film, and optically detecting the presence of the amphiphile by measuring a change in birefringence exhibited by the LC film.

System and method thereof for accurate optical detection of amphiphiles at a liquid crystal interface

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.

Super-piezoelectric composite fiber mats for power generation and soft actuators

There are provided methods for creating energy conversion devices based on the giant flexoelectric effect in non-calamitic liquid crystals. By preparing a substance comprising at least one type of non-calamitic liquid crystal molecules and stabilizing the substance to form a mechanically flexible material, flexible conductive electrodes may be applied to the material to create an electro-mechanical energy conversion device which relies on the giant flexoelectric effect to produce electrical and/or mechanical energy that is usable in such applications as, for example, power sources, energy dissipation, sensors/transducers, and actuators.

Method of determining a flexoelectric effect in a liquid crystal material

The invention provides a simple and cost-effective method for preparing particles such as anisotropic semiconductor nanoparticles (e.g. CdS) and devices thereof. The method comprises (i) dispersing at least part of particle-forming reactants in a self-organized medium such as surfactant-aqueous solution system, and (ii) conducting a particle-forming reaction using the particle-forming reactants dispersed in the self-organized medium under shear condition to form the particles. The anisotropic property of the particles is controlled at least partially by the shear condition. The invention may be used to prepare quantum dots in a liquid crystal, and various devices such as nonlinear optics, optoelectronic devices, and solar cells, among others.

Method for preparing anisotropic particles and devices thereof

Electro-mechanical energy conversion devices and systems

Method of creating an electro-mechanical energy conversion device

The invention is directed to liquid crystal display and electro-optical devices having faster switching times, a wider viewing angle, continuous gray level, improved transmittance of the clear state, approximately no threshold voltage and low power consumption. The aspects of the invention are achieved by a liquid crystal device comprising an orthogonal nematic, smectic or columnar liquid crystal phase, which is uniaxial in absence of electric field, but becomes biaxial when electric field is applied normal to the director (in between electrodes for planar alignment, or in-plane electric field in case of homeotropic alignment). This electric field induced biaxiality (EFIB) mode is provided using any dielectric orthogonal nematic, smectic or columnar bent-core liquid crystal phase. The nature of the switching is dielectric (not piezoelectric) and does not involve variation of layer spacing variation, so as to be mechanically much more stable than prior systems. The high switching speed combined with a large change in the effective birefringence and constant optical axis of the liquid crystal materials provide useful features in various applications, such as liquid crystal television, beam steering, spatial light modulators, and a variety of other applications.

Fast switching electro-optical devices using banana-shaped liquid crystals

A new way of generating electrical power by changing the dielectric properties of liquid crystals by mechanical means is described. Such a method and device take advantage of the nature of the liquid crystal as the dielectric material in a capacitor. A broad range of materials, including various liquid crystalline materials, as well as additional mechanisms (flexoelectric polarization) to fully exploit the potential of this mechanism may be realized. Applications of this technology may be useful in wearable personal electric generators as well as in noise damping materials/devices, which not only absorb and dissipate sound, but use it to generate electric power.

Electric power generation using liquid crystals

Novel nanoscale discotic liquid crystalline porphyrins, methods for their preparation, and device fabrication are disclosed. These compounds are capable of being used as high-efficiency photovoltaic materials, organic semiconducting materials, and organic light emitting materials.

Nanoscale discotic liquid crystalline porphyrins

A liquid crystal device comprising tilted smectic phases of banana-shaped liquid crystal molecules is disclosed. A method for fabricating a light modulating device is also disclosed. The method comprises the steps of providing a pair of substrates with a cell gap therebetween and permanently disposing at least one banana-shaped liquid crystal material into said cell gap. The present invention also provides a method of generating an image, comprising providing a pair of substrates with a cell gap therebetween, providing transparent electrodes on each of the substrates adjacent to the cell gap, disposing at least one banana-shaped liquid crystal material into the cell gap; and applying an electric field across the electrodes. The tilted smectic phases of banana-shaped liquid crystal may be in either a racemic or a chiral state. The application of a sufficiently high electric field transitions the banana-shaped liquid crystal material between the racemic and chiral states, and both the racemic and the chiral states are stable in the absence of an electric field.

Electro-optical devices from banana-shaped liquid crystals

A liquid crystalline paste material is formed by polymerization of a solution containing a mesogenic solvent and monomeric material in bulk. The paste provides an improved method of preparing thin electrically addressable light modulating films by coating the paste onto a suitable substrate.

Method of preparing thin liquid crystal films

A method for promoting uniform 'bookshelf' textures in light modulators using smectic C* liquid crystal is disclosed. The method comprises the steps of confining smectic C* phase liquid crystal between parallel substrates having inner surfaces treated to promote homeotropic alignment of the liquid crystal near the inner surfaces, generating an electric field normal to the inner surfaces of the substrates and biasing the liquid crystal in a direction parallel to the inner surfaces of the substrates to induce the formation of smectic layers normal to the inner surfaces of the substrate. For example, the perturbation may be carried out by supplying a cyclic shear to one of the substrates or by means of a magnetic field parallel to the substrates. Reversal of the polarity of the electric field switches the material between two stable bookshelf textures. These textures are homogeneous in alignment even near the inner surfaces of the substrates, and the anchoring of the molecules near the substrates changes as the material is switched between bookshelf textures.

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Kent, OH, United States of America

Antal Jakli