Sharp Kabushiki Kaisha Corporation

The Secretary of State for Defence in Her Britannic Majesty's Government

Other

The Secretary of State for Defence

Sharp Laboratories of Europe Limited

Michael John Towler

Paul Bonnett

Harry Garth Walton

Martin David Tillin

Akira Tagawa

Elizabeth Jane Acosta

Michael Geraint Robinson

Craig Tombling

Nicholas Mayhew

Diana Cynthia Ulrich

Damien Gerard McDonnell

Jonathan Rennie Hughes

Guy Peter Bryan-Brown

Kirstin Ann Saynor

Edward P Raynes

Harald Reinhart Bock

Sandra Gilmour

Mitsuhiro Koden

John Clifford Jones

Paul Antony Gass

Tomoaki Kuratate

Adrian Marc Simon Jacobs

Masaaki Kabe

Akira Sakaigawa

David Charles Scattergood

Jonathan Harrold

Yuichiro Yamada

Akiyoshi Fujii

Mitsuhiro Shigeta

Emma Jayne Walton

Keisaku Nonomura

Teiyu Sako

Aya Miyazaki

Duncan James Anderson

Tadashi Kawamura

Alistair Graham

Andrew James Hudson

Judy Megan Rorison

Michael Stuart Weaver

Lesley Anne Judge

Emma Jayne Beynon

Martin S Bancroft

Alastair Graham

Brian Henley

A liquid crystal device comprises a nematic liquid crystal, voltage means for applying a voltage across said liquid crystal, and two substrates () each provided with an alignment layer (), wherein: said liquid crystal is sandwiched between said two substrates (); said nematic liquid crystal can be placed in at least one operating state and at least one non-operating state, and at least one of said alignment layers () is provided with a plurality of surface protrusions () formed from an anisotropic material.

Nematic liquid crystal devices comprising surface protrusions formed of anisotropic material for nucleation of an active region

A surface mode liquid crystal device, for example of the pi-cell type, comprises a layer nematic liquid crystal ( ) disposed between alignment layers ( ) and an electrode arrangement ( ). The nematic liquid crystal has viscosity coefficients &eegr; , &eegr; and &ggr; , such that (&eegr; -&eegr; )/&ggr; &gE;1.15 or (&eegr; -&eegr; )/&ggr; &lE;0.9.

Liquid crystal device and display

A reflective liquid crystal device comprises in sequence a linear polarizer, a retarder arrangement comprising two retarders, and a reflector. A first of the retarders provides a retardation of m&lgr;/2 and a second of the retarders provides a retardation of n&lgr;/4, where m is an integer and n is an odd integer, and wherein at least one of the first and second retarders comprises a Bistable Twisted Nematic (BTN) liquid crystal. This BTN retarder is switchable between a first state in which the retarder provides a retardation of m&lgr;/2 or n&lgr;/4 and a second state in which the retardation is zero.

Reflective liquid crystal devices

A broadband optical retardation device, such as may be used for polarisation encoding of display information or in diffractive optical systems, includes a patterned uniform half wave plate retarder in combination with a non-patterned uniform quarter wave plate retarder having an optic axis oriented at 90&deg; to the xz plane. The patterned retarder consists of alternating first and second regions having first and second optic axes at different orientations to a reference axis, for example at &plus;22.5&deg; and &minus;22.5&deg; to the xz plane. Considering light of wavelength &lgr;&deg; incident on the retarder and linearly polarised in the xy plane, such light is differently polarised by the regions, and the light output by the device includes regions in which the light is right circularly polarised and regions in which the light is left circularly polarised. In the case of incident light of wavelengths greater or less than &lgr;&deg;, the output light becomes progressively more linearly polarised as the wavelengths departs to a greater extent from the ideal value, but not to the same extent as would be the case if the device consisted simply of a patterned single layer acting as a quarter plate retarder.

Broadband optical retardation device

A liquid crystal display device comprises: a layer of a chiral liquid crystal material disposed between first and second substrates; and means for applying a voltage across the liquid crystal layer. A first region of the liquid crystal layer is an active region for display and a second region of the liquid crystal layer is a nucleation region for generating a desired liquid crystal state in the first region when a voltage is applied across the liquid crystal layer. The ratio of the thickness d of the liquid crystal layer to the pitch p of the liquid crystal material has a first value (d/p) in the first region of the liquid crystal layer and has a second value (d/p) different from the first value in the second region of the liquid crystal layer. The value (d/p) of the ratio of the thickness d of the liquid crystal layer to the pitch p of the liquid crystal material in the second region of the liquid crystal layer is selected such that, when no voltage is applied across the liquid crystal layer, the liquid crystal state stable in the second region of the liquid crystal layer is topologically equivalent to the desired liquid crystal state.

Liquid crystal display device

A luminescent device having first and second light-emitting regions, wherein the first light-emitting region emits, in use, a first polarised light and the second light-emitting region emits, in use, a second polarised light different from the first polarised light.

Luminescent device and a liquid crystal device incorporating a luminescent device

A method of making a patterned retarder of the present invention includes the steps of providing an alignment layer rubbing the alignment layer in a first rubbing direction, masking with a mask at least one first region of the alignment layer, to reveal at least one second region of the alignment layer, rubbing the at least one second region through the mask in a second rubbing direction different from the first rubbing direction, removing the mask, disposing on the alignment layer a layer of birefringent material whose optic axis is aligned by the alignment layer, and fixing the optic axis of the birefringent layer.

Method of making a patterned retarder, patterned retarder and illumination source

A display device and method driving a display device makes use of the dynamic variation in the brightness of a surface mode liquid crystal device cell having a liquid crystal layer with a non-zero twist angle. The liquid crystal layer is switched before the equilibrium value of the brightness has been reached, so as to make use of the non-equilibrium increased brightness and so increase the brightness of the display.

Method of driving a liquid crystal display device, and a liquid crystal display device

A pi-cell liquid crystal device comprises a nematic liquid crystal layer ( ) disposed between alignment layers ( ) which provide a pretilt such that, at a zero applied field, the energy of the H-state is less than the energy of the V-state, which is less than the energy of the T-state. A drive arrangement ( ) switches the pi-cell by applying a first electric field, at which the energy of the V-state is less than the energy of each of the H-state and the T-state, or a second smaller electric field, at which the energy of the H-state is less than the energy of each of the V-state and the T-state. The T-state may thus be avoided while maintaining high switching speeds.

Liquid crystal device

A surface mode liquid crystal device, comprising a liquid crystal layer disposed between first and second alignment layers for substantially parallel-aligning the liquid crystal layer, the first alignment layer comprising a plurality of regions defining respective picture elements, each of the regions comprising a plurality of sub-regions, the plurality of sub-regions each comprising at least one first sub-region for aligning the adjacent liquid crystal In a first alignment direction and at least one second sub-region for aligning the adjacent liquid crystal in a second alignment direction substantially different from that of the first alignment direction.

Multi-domain surface mode device

A reflective liquid crystal device comprises a polarizer and a mirror between which are disposed several retarder. At least one of the retarders is a variable liquid crystal element whose optic axis is switchable so as to switch the device between a reflective state and a non-reflective state. In the non-reflective state, the total retardance of the retarders between the polariser and the mirror is equal to an odd number of quarter wavelengths for a wavelength at or adjacent the middle of the visible spectrum.

Reflective liquid crystal device

An OCB device comprises upper and lower substrates, each provided with an alignment layer. A liquid crystal layer is provided between the substrates. The lower substrate has a low pre-tilt in regions A and C, so that an H-state is stable in these regions when no voltage is applied across the liquid crystal layer. Region B has a high pre-tilt on the lower substrate, so that a HAN state is stable in region B under zero applied voltage. When a voltage is applied across the liquid crystal lever, a V-state is formed at the interface between the HAN-state and the H-states. This V-state then displaces the H-states in regions A and C. The high pre-tilt region, region B, is acting as a nucleation region. The V-state forms at a lower applied voltage than if the nucleation region is not provided.

Liquid crystal display device and a method of manufacture thereof, and a substrate and a method of manufacture thereof

A liquid crystal display element is formed by providing a liquid crystal layer made of ferroelectric liquid crystal material between electrode substrates. One of the electrode substrate is composed of a substrate, electrodes, an insulating film, and an alignment film, while the other substrate is composed of a substrate, electrodes, an insulating film, and an alignment plate. The alignment film is formed by mixing a substance with ionic bond in an alignment film material and thereafter applying the mixture on the paired substrates on each of which the electrodes and the insulating film are provided. With this arrangement, ions are eluted from the alignment films thus formed into the liquid crystal layer, thereby becoming dispersed therethrough homogeneously. This remarkably reduces influences of display history, and half-tone display with excellent response characteristics can be realized, being not affected by display history.

Liquid crystal display element and manufacturing method thereof

A method of addressing a liquid crystal device having a plurality of scanning electrodes and a plurality of data electrodes defining a plurality of pixels at the intersections between at least one of the plurality of scanning electrodes and at least one of the plurality of data electrodes, the method comprising applying one frame of a scanning signal to one of the plurality of scanning electrodes, applying a data signal to at least one of the plurality of data electrodes, one frame of the scanning signal comprising n strobe portions, where n is an integer greater than 1, for co-operation with the at least one data signal to address one of the plurality of pixels, and at least one blanking portion, the number of blanking portions not exceeding (n&minus;1).

Liquid crystal device and method of addressing liquid crystal device

A liquid crystal device is addressed in a multiplexed manner by a scanning signal applied in turn to a first set of electrodes together with data signals applied to a second set of electrodes. The first and second sets of electrodes define a plurality of pixels. The pattern to be exhibited by the device determines the waveform applied to the second set of electrodes which can vary between extremes of frequency. This has adverse effects on device performance, particularly with regard to contrast. To ameliorate the problem a low frequency signal is added to the scanning signal which incorporates a known strobe pulse. This low frequency signal reduces the effect on the pixels of the extremes of data signal frequency.

Liquid crystal device and method addressing liquid crystal device

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Oxford, United Kingdom

Michael John Towler