60 results about "Bistability" patented technology

An electrophoretic medium comprises a plurality of particles suspended in a suspending fluid, the particles being capable of moving through the fluid upon application of an electric field to the medium, the fluid having dissolved or dispersed therein a polymer having a number average molecular weight in excess of about 20,000, the polymer being essentially non-absorbing on the particles. The polymer improves the bistability of the display (i.e., the period for which a written image persist without the display being refreshed) but does not greatly increase the viscosity of the suspending fluid, thus keeping the switching time of the display within reasonable limits. The medium may be encapsulated, or may be in the form a polymer-dispersed electrophoretic medium.

The invention relates to methods and materials for controlling stability and color intensity in an electrophoretic display element. Filler particles in the electrophoretic display element, serves as a medium that the electrophoretic particles must travel through during switching between optical states of the display. The filler particles provide improved control over the color intensity of the electrophoretic display element. In addition, the filler particles create resistance to the migration of the electrophoretic particles, thereby improving the bistability of the electrophoretic displays and inhibiting settling of the electrophoretic particles. Also, migration resistance provided by the filler particles can enable threshold addressing of an electrophoretic display.

Polymer-coated pigment particles produced using atom transfer radical polymerization provide electrophoretic media having improved bistability without requiring addition to the electrophoretic fluid of additives which increase switching time.

A ferroelectric liquid crystal display including an upper base plate and a lower base plate which are disposed apart from each other at a predetermined distance, electrode layers respectively formed on the upper base plate and the lower base plate facing each other, orientation layers respectively formed on the electrode layers and treated by rubbing in a first rubbing direction and a second rubbing direction which intersect at a predetermined angle, and a liquid crystal layer disposed between the orientation layers and filled with a ferroelectric liquid crystal having a bookshelf structure. Due to the ferroelectric liquid crystal display and the method of manufacturing the same, the ferroelectric liquid crystal of the bookshelf structure can stably twist by the treatment of the orientation such that an afterimage phenomenon is prevented and further a low threshold voltage and a bistability can be obtained.

The invention relates to a negative dielectric anisotropy liquid crystal material composite and a display element containing the liquid crystal composite. The negative dielectric anisotropy liquid crystal material composite contains at least one composite which is composed of compounds and expressed as general formulas (I) and (II) as a first component, at least one composite which is composed ofchemicals and expressed as a general formula (III) as a second component and at least one composite which is composed of chemicals and expressed as general formulas (IV) and (V) as a third component.The composite has significant negative dielectric anisotropy, a wide-enough nematic temperature range and refraction index anisotropy range, low viscosity and very excellent ultraviolet (UV) irradiation resistance performance and can fully satisfy requirements on the liquid crystal materials for high-grade decorative PDLC and simultaneously, in optical and electrical property, satisfy the requirements on the liquid crystal materials for PDLC display light valves with bistability.

The present invention is directed to methods for improving the performance of an electrophoretic display by modifying the display cell surface. More specifically, the methods are directed to modification of the microcup surface after the microcups are released from the mold. The microcups which have undergone any of the treatment methods of the invention show significant improvement in their surface properties, such as chemical functionality, surface roughness, surface tension, morphology, surface charge, surface reflectivity, surface conductivity and optical properties, particularly optical density in the visible light region. An electrophoretic display formed from the treated microcups has many advantages. For example, the display shows a higher contrast ratio, lower electro-optic response time, lower driving voltage, longer shelf life, higher imageincreasing bistability and higher threshold voltage. In addition, it exhibits an improved image quality by reducing undesirable scum formation or irreversible particle deposition on the microcup surface.

This invention relates to reflective cholesteric displays without using Bragg reflection. The helical pitch of the cholesteric liquid crystals may or may not be tuned in a visible wavelength, but its Bragg reflection will never be displayed. An elliptical polarizer with properly designed retardation and lamination positioned at the front of the display will be able to eliminate the Bragg reflection over a large viewing cone. The function of the display cell structure is merely a light shutter to switch the incident light ON and OFF. In the black-and-white display mode, the white state is achieved from the metal reflection in the cholesteric planar texture area; and the black state is obtained by cholesteric's depolarization effect and polarizer's filtration effect in the cholesteric focal conic texture area. In the full color mode, the full color state is created by the metal reflector and the micro-color filter in the cholesteric planar texture area; and the black state is realized in the cholesteric focal conic texture area. The reflective cholesteric display, remaining its long-term bistability but not applying the narrow-band Bragg reflection, initiates novel displays with a neutral wide-band reflection.

Example embodiments provide an electrochromic device using polyphthalate as an electrochromic material and a process for preparing the same. The electrochromic device in accordance with example embodiments enables the production of a solid nanoscale electrochromic device having a bistability using polyphthalate as an electrochromic material, and easy formation of a red electrochromic layer which was not reported in a conventional art. Accordingly, the electrochromic device of example embodiments can be usefully employed for fabrication of RGB color electrochromic displays.

The present invention relates to a switchable infrared ray-visible ray reflection electrochemical mirror having high electrochemical stability and bistability, in which a stripping phenomenon of a metal thin film can be prevented and bistability can be improved through a process of increasing electrochemical stability of a reflective film from an electrode composition and an ionic liquid electrolyte composition having various compositions. In the proposed electrochemical mirror apparatus, since the metal thin film formed by electric reduction is not stripped from a transparent electrode through a surface treatment process, a more stable apparatus can be provided, and even though a voltage is not applied to the metal thin film, the thin film is prevented from being oxidized by using an optimized ionic liquid electrolyte, thus providing the effective electrochemical mirror apparatus where the metal thin film is continuously maintained.

A liquid crystal device is constituted by a chiral smectic liquid crystal and a pair of substrates sandwiching the chiral smectic liquid crystal therebetween and each having thereon an electrode for applying a voltage to the liquid crystal. At least one of the substrates being provided with an alignment control film comprising a specific aromatic polyimide which has been subjected to a uniaxial aligning treatment. The chiral smectic liquid crystal assumes bistability in a chiral smectic temperature range when incorporated in a test cell which is not provided with an alignment control film and has been subjected to shearing treatment. In the liquid crystal device including the polyimide alignment control film, the chiral smectic liquid crystal at least has a voltage-transmittance characteristic such that an effective tilt angle and a transmittance continuously change depending on an electric field applied thereto.

The present invention is directed to an electrophoretic dispersion comprising charged pigment particles dispersed in a solvent or solvent mixture, wherein the pigment particles have an average aggregation size more than 2 times their primary size. The electrophoretic dispersion of the present invention is capable of improving image bistability through adjusting the aggregation size of the charged pigment particles.

The present invention is directed to an electrophoretic dispersion comprising charged pigment particles dispersed in a solvent or solvent mixture, wherein at least one type of the charged pigment particles has an aggregation size about 2 to about 10 times their primary size and/or has a PDI in the range of 0.1 to 0.3. The electrophoretic dispersion of the present invention is capable of improving both image bistability and contrast ratio through adjusting the size distribution of the charged pigment particles.

An electronic or electro-optic device according to an embodiment of this invention has a first electrode, a second electrode spaced apart from the first electrode, and an organic composite layer disposed between the first electrode and the second electrode. The organic composite layer is composed of an electron donor material, an electron acceptor material, and a polymer matrix material. The organic composite layer exhibits substantial bistability of an electrical property.

The invention relates to a similar no-electric solvent resistance composite functional ball, in particular to a urea-formaldehyde resin coating polystyrene ball/titanium dioxide nanometer particle. The similar no-electric solvent resistance composite functional ball is urea-formaldehyde resin coating polystyrene ball/titanium dioxide nanometer particle. The preparation method comprises: using polyvinylpyrrolidone or silane coupler to modify polystyrene ball/titanium dioxide nanometer particle; using in-situ polymerization to condensate urea-formaldehyde prepolymer on the surface of the nanometer particle to form dense and transparent similar no-electric urea-formaldehyde resin coat, to obtain solvent resistance particles. The similar no-electric solvent resistance composite functional ball is matched with disperse mediums and can resist the corrosion of non-polar solvent, to stabilize the particles in the solvent and overcome the defects caused by using dyes, thereby providing a base for stabilizing two dyes of different colors in electrophoretic liquid to realize bistability display.

A nonvolatile polymer bistability memory device using nano particles that are formed in a polymer thin film and a method of manufacturing the nonvolatile polymer bistability memory device are provided. The nonvolatile polymer bistability memory device includes a semiconductor substrate, a first electrode on the semiconductor substrate, a polymer thin film on the first electrode, nano particles embedded into the polymer thin film, and a second electrode on the polymer thin film. The nonvolatile polymer bistability memory device does not need any source and drain to operate, and the method of manufacturing the nonvolatile polymer bistability memory device can guarantee high production efficiencies while maintaining low manufacturing costs.

The present invention provides a switching element in which the compositional deviation of material is suppressed and that attains uniform bistability performance and is suitable for mass production. In a switching element comprising an organic bistable material, which exhibits two stable states in resistance under applied voltage, arranged between at least two electrodes, the organic bistable material comprises at least a compound having an electron-donating functional group and an electron-accepting functional group in each molecule. It is preferred that, for example, an aminoimidazole type compound, a pyridone type compound, a stilbene type compound or a butadiene type compound be used as the above compound.

A method for medical image enhancement based on image transform resonance A novel method for Stochastic Resonance of medical image enhancement device based on the Integral Transform of the image, comprising: generating specific types of integral transforms like radon transform for CT, Fourier transform for MRI with image transform component; preparing stochastic perturbation waveform, with perturbator component performing the stochastic resonance on the image transform, with stochastic resonator component; characterizing the image enhancement factor of the SR-processed image with performance monitoring component; adjusting and controlling the bistability parameters of the double-well system that induces stochastic resonance with control component; arranging the provisional display of the array matrix of the SR-enhanced images, as the bistability parameters are varied with matrix display component; subjecting the final image to the step of display with final image display component.