Nemoptic

Dic Corporation

Nemoptic, S.a.

Centre National De La Recherche Scientifique

Instituto Nationale Per La Fisica Della Materia

Ivan N Dozov

Philippe Martinot-Lagarde

Daniel Stoenescu

Georges E Durand

Jean-Claude Dubois

Haruyoshi Takatsu

Kiyofumi Takeuchi

Hidetoshi Nakata

Jacques Angele

Didier Gallaire

Sandrine Lamarque-Forget

Eric Polossat

Michele Giocondo

Takeshi Kuriyama

Alain Boissier

Stéphane Joly

Romain Vercelletto

Riccardo Barberi

Roberto Bartolino

Jun Li

Julien Roux

Cécile Barron

Bertrand Pecout

Sebastien Jacquier

Sébastien Perny

Luc Faget

Sandrine Forget

Lorenzo Bajic

Olivier Ou Ramdane

Jean Claude Dubois

Philippe Auroy

Eric Raspaud

Ioannis Lelidis

Maurizio Nobili

Stephane Joly

Ricardo Barberi

The present invention provides a nematic liquid crystal composition suitable for a bistable nematic liquid crystal display. A bistable nematic liquid crystal display having a wide nematic phase temperature range and operating temperature range can be obtained by using a nematic liquid crystal composition comprising at least 20% by weight of a specific liquid crystal compound (A) having a polar group and 5 to 50% by weight of a specific liquid crystal compound (B) not having a polar group, along with comprising, in the compound (B), at least 3% by weight of a specific liquid crystal compound having a alkenyl group.

Nematic liquid crystal composition and bistable nematic liqud crystal display

A nematic liquid crystal composition of the present invention includes at least 20% by weight of one, or two or more compounds selected from compound group A; and 5 to 50% by weight of one, or two or more compounds selected from compound group B, wherein the relative proportions of the above-mentioned compounds used in the nematic liquid crystal composition is determined to simultaneously obtain the specific physical characteristics for the composition, and an anchoring breaking voltage Uis less than or equal to 25 V when the product (&#x394;n&#xb7;d) of the refractive index anisotropy (&#x394;n) at 20&#xb0; C. and the thickness (d) is 140 nm and the liquid crystal composition is confined between two substrates for a bistable nematic liquid crystal display in which at least one of the substrates have a weak zenithal anchoring force.

Nematic liquid crystal composition and bistable nematic liquid crystal display

The invention concerns a liquid crystal display device comprising two substrates () provided with respective electrodes () and located on either side of a layer of liquid crystal molecules () and means defining two stable states for the liquid crystal molecules, in the absence of an electric field. The invention is characterized in that it further comprises a mask () including transparent areas () allowing through only the design of the areas to be visualized and opaque areas () covering the rest of the surface of the display and among others the zones not addressed by the electrodes () and, in that the electrodes () are configured such that their edges are located in zones outside the transparent areas () of the mask (100), in that each electrode block () consists of the assembly of interconnected elementary areas through multiplexing and of intermediate zones located beneath the opaque areas () of the mask (), and that on at least one of the substrates (), the electrodes are formed of blocks () which cover the entire surface of the substrate except the intermediate zones () of small width required for providing electrical insulation between the blocks.

Liquid crystal display enhanced in particular by elimination of harmful effects on the edges of addressed zones

A method of using a liquid crystal composition in a bistable liquid crystal device having a weak zenithal anchoring comprising at least 40% by weight of compounds with strong molecular polarisability and strong dipole moment.

Nematic liquid crystal mixtures for use in bistable display devices

The present invention relates to a nematic bistable display device, characterized in that it comprises control means () for producing, after the anchoring is broken, hybrid textures in which two bistable textures coexist in a controlled proportion within the same pixel, these being separated by 180&#xb0; volume disclination lines or by 180&#xb0; reorientation walls on one of the surfaces, and means () for the long-term stabilization of the hybrid textures by transformation of the volume lines into surface walls and the immobilization of these walls on the surface.

Nematic liquid crystal bistable display device with grey level

Nematic liquid crystal mixtures with weak zenithal anchoring energy for bistable display devices, comprising at least 40% by weight of compounds with strong molecular polarisability and strong dipole moment.

Nematic liquid crystal mixtures for bistable display device

The invention relates to a bistable nematic liquid-crystal device comprising: alignment means, which orient the liquid crystal, means designed to apply electrical signals which allow switching, by breaking the anchoring on at least one of the two substrates, between two distinct textures, and means designed to promote the establishment of that one of the said textures giving the off state in the liquid crystal covering the inter-electrode spaces.

Bistable nematic liquid crystal display device with improved optical mask, having textures differing by about 180&#xb0; twist, and off state in the liquid crystal covering the inter-electrode spaces

A method of making nematic liquid crystal devices where low energy zenith anchoring of the liquid crystal is obtained over confinement plates. A polymer or copolymer is deposited based on PVC onto a substrate. The polymer deposit is stabilized. An azimuth orientation is defined for the deposit to induce controlled azimuth anchoring of the liquid crystal.

Method for producing a liquid crystal device with low zenithal anchoring energy, and resulting device

Method of producing nematic liquid-crystal devices, wherein a low zenithal anchoring energy of the liquid crystal is obtained on at least one of its confinement plates by the steps consisting in:

Method of producing nematic liquid-crystal devices

The present invention relates to a reflective liquid crystal display device comprising a liquid crystal material ( ) contained between two parallel substrates ( ) provided with aligning means on the electrodes to orient the liquid crystal and enable at least two alternative distinct textures that are stable or metastable in the absence of a field to be obtained, means for applying electrical signals to the liquid crystal to perform switching by enabling anchoring on at least one of the two substrates to be broken, a polarizer ( ) associated with the front face of the device and oriented at an angle lying in the range 15&deg; to 75&deg; relative to the director of the liquid crystal on the front face of the device, and a specular or diffusing reflective element ( ) placed at the rear face of the liquid crystal.

Reflective bistable display device incorporating a liquid crystal material

The invention concerns a bistable device comprising a liquid crystal material, aligning means, which orient the liquid crystal to provide two stable or metastable textures, means for applying electric signals enabling to switch between the two textures, a polarizer ( ) associated with the front surface of the device, placed inside or outside same, a reflective, specular or diffusing element, placed on the rear surface of the liquid crystal, inside or outside the device, allowing light to pass through the device twice and to return towards the observer or towards additional optical elements, and a compensator ( ), placed between the polarizer and the reflective element, with an optical retardation d &Dgr;n close to &lgr; /4.

Bistable device for reflection display with inverse contrast

The present invention relates to a liquid crystal display device comprising a liquid crystal material sandwiched between two confinement plates ( ), the device being characterized by the fact that at least one of the plates ( ) is provided with treatment which defines degenerate or nearly degenerate azimuth anchoring without azimuth orientation memory.

Liquid crystal device comprising anchoring means on at least one confinement plate providing a degenerated orientation

A display device including two parallel transparent plates (,) having transparent electrodes on the inner surfaces thereof and containing a liquid crystal material (,). The device includes means defining a monostable anchoring for each plate (,), means (,) controllable to break at least one of the anchorings, and means for thereafter inducing volume bistability.

Bistable liquid crystal display device in which nematic liquid crystal has monostable anchorings

The present invention relates to a display device based on liquid crystals, comprising a nematic liquid-crystal material (10) with positive dielectric anisotropy sandwiched between two transparent confinement plates (20, 30) each provided with transparent electrodes (22, 32), characterized in that at least one of the plates, (30), defines a quasi-bistable anchoring and in that it is provided with main electrical supply means (40) suitable for applying a temporary electric field to the liquid-crystal material (10) capable of breaking the anchoring on the aforementioned plate (30) and subsequently allowing, due to the effect of hydrodynamic instabilities, various localized orientations of the liquid-crystal molecules (10) corresponding to the preferred orientations of the quasi-bistable anchoring.

Bistable display device based on nematic liquid crystals allowing grey

An electro-optical method and apparatus uses liquid crystals. The method includes the step of filling a space between two parallel transparent plates with a material which comprises molecules having nematic properties, the structure of the molecules initially defining a substantially rectilinear nematic director perpendicular to the plates. A structure is then conferred on the material defining a second nematic director curved at least once in a plane perpendicular to the plate by application of a high frequency electrical field to the material, such that the second nematic director arrives substantially perpendicularly at at least one of the two plates. A twist is imparted to the second nematic director along a component at right angles to said plane perpendicular to the plates to impart a twist in the second nematic director. Light is caused to arrive with an incidence substantially at right angles to one of the plates to pass through the material, a rotation of polarization of the light, at an outlet from the plates, depending on the twist imparted to the second nematic director.

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Gif-sur-Yvette, France

Ivan N Dozov