Zbd Displays Limited

Sharp Kabushiki Kaisha Corporation

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

Merck Patent Gmbh

Qinetiq Limited

The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland

Other

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

Hewlett-packard Development Company, L.p.

Merck Patent Gesellschaft MIT Beschrankter Haftung

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

F. Poszat Hu, LLC

Holographic Imaging LLC

The Secretary of State for Defence in Her Brittanic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland Defence Evaluation and Research Agency

John Clifford Jones

Guy Peter Bryan-Brown

Damien Gerard McDonnell

Ian Charles Sage

Jonathan Rennie Hughes

Emma Louise Wood

Andrew John Slaney

Carl Vernon Brown

Matthew Francis

Mitsuhiro Koden

Alistair Graham

Stephen M Beldon

Marc John Goulding

Michael John Towler

John William Goodby

Michael Hird

Teiyu Sako

Richard Jonathan Miller

Madeline J Bradshaw

Ian Robert Mason

Victor Chaklam Hui

Simon David Haslam

Robert William Bannister

Richard M Amos

Paul Anthony Gass

Marie Harper Anderson

Steve Beldon

Peer Kirsch

George W Gray

Mark John Goulding

Kenneth J Toyne

Takaji Numao

Paul Antony Gass

Nobuyuki Itoh

Aya Miyazaki

Michiyuki Sugino

Timothy Jonathan Phillips

Akira Sakaigawa

Cecile Schott

Victoria Minter

David Charles Scattergood

Rachel Patricia Tuffin

Robert Andrew Lewis

Doina Ionescu

David Richard Beattie

Simon Gooch

Philip T Worthing

Clive Mayne

Steve Taylor

Karl Philip Lymer

Richard Simms

David Walker

Paul Hindmarsh

David Dix

Markus Wahle

An electrically switchable optical modulator for modulating an optical wavefront transmitted therethrough, comprising a birefringent first optical element and a birefringent second optical element each having respective ordinary and extraordinary refractive indices. A birefringent liquid crystal material is sandwiched between the first and second optical elements. The extraordinary refractive index of the liquid crystal material is electrically switchable between: a first state in which it has a first value; and, a second state in which it has a second value different from the first value. One or both of the first value and the second value is un-matched to the extraordinary refractive index of the first optical element in respect of light polarised in a first direction of linear polarisation, and is un-matched to the extraordinary refractive index of the second optical element in respect of light polarised in a second direction of linear polarisation orthogonal to the first direction. This switchably renders a relative contrast in extraordinary refractive index as between the liquid crystal material and the first and second optical elements for modulating said wavefront.

Optical elements

The invention relates to a method of patterning a layer formed from a fixable material such as photopolymer on a surface in a desired pattern. The method involves coating selected areas of the substrate with an adhesion promoter and subsequently coating the fixable material. The fixable material is then fixed, for instance by curing by exposure to UV radiation. The adhesion promoter is adapted to have a surface energy which is designed to adhere to the substrate or selected areas thereof and also to the fixed material such that fixed material may be easily removed from areas of the substrate not coated with adhesion promoter but retained in areas where the adhesion promoter has bonded to the substrate.

Method for patterning a surface using selective adhesion

In a liquid crystal device a substrate () favors at least two stable or metastable differently directed liquid crystal alignments, and switching means for causing the liquid crystal material to switch between the alignments includes means arranged for optically irradiating said device. The latter may provide linearly polarized light () for inducing a torque on the liquid crystal to determine the alignment direction, and may optionally cooperate with a second energy supplying means such as an electric field (V) for assisting and switching. Alternatively, the alignment of the liquid crystal may be switched by a second energy supplying means such as an electric field, the light serving to produce heat to aid the switching. Either or both energy sources may be applied locally for switching of selected areas or pixels. Energy levels at the bistable substrate may be adjusted by the use of an oligomeric additive (slippery surface). As shown, the alignment at the surface of an opposed substrate () optionally follows the alignment at substrate ().

Bistable liquid crystal devices

A display systemfor displaying information at a point of product display in a retail outlet comprising a communicatorfor transmitting display information to a remote display module, the display modulebeing adapted in a first, low power mode to display information and in a second, higher power mode periodically, in a predetermined manner, to communicate with the communicator, the systempreferably being configured to enable determination of the accuracy and automated correction of the synchronization of a periodic communication between the communicatorand the display modulewhile the display modulecontinues to switch between first and second modes of operation enabling a low overall consumption of power by the display moduleand more preferably wherein the display moduleis adapted to switch between first and second power modes between receipt of a synchronization signal and a display information signal from the communicator

Display system

A photopolymer mixture is capable of use for a liquid crystal alignment layer. An alignment layer is formed from such a photopolymer mixture. The mixture comprises at least two polymerisable materials which are blended together in proportion so as to give a predetermined, preferably low, surface energy. A low surface energy, e.g., less than 4&#xd7;10N/m, can result in an alignment layer which imparts a particular orientation to liquid crystal molecules with out requiring any post-cure treatments. The polymerisable materials may be monomers, oligomers, or diluents that form long chain molecules when cured, and the mixture may contain additives to lower the overall surface energy.

Liquid crystal alignment layer

A liquid crystal device comprises a layer () of a nematic liquid crystal material contained between two cell walls () each carrying electrode structures () and an alignment surface (). The alignment layer () on one or both cell wall (), is formed of a plurality of small (&#x3c;15 &#x3bc;m) surface features each separably capable of providing a bistable pretilts and an alignment direction and collectively causing larger variations of molecular orientation across the layer (). The device may be switched between a light transmissive state and a light non-transmissive state. The small surface features may be areas of grating (), protrusions (), or blind holes (), separated by mono stable flat surfaces (Fm) coated with a homeotropic alignment layer. Preferably, the grating etc provides bistable switching operation between a low surface tilt and high surface tilt, and the low tilt alignment direction varies between adjacent grating areas.

Bistable nematic liquid crystal device

This invention relates to a liquid crystal device wherein the surface profile of a surface alignment grating stabilises at least one stable state. The invention involves the introduction or breaks () or discontinuities into the grating () to divide the grating into a plurality of groove segments. The breaks are discontinuities in the grating in the groove direction, the grating having substantially the same groove direction on each side of the break. The introduction of breaks prevent free movement of defects along the groove of the grating and therefore help to stabilise the desired liquid crystal configuration, either a Defect state or a Continuous state. Suitable breaks involve gaps () in the groove ridges (), necks () between the groove ridges () and slips or relative displacement () of the grating.

Liquid crystal device including an alignment grating with breaks therein

A device is described that comprises a layer of material () disposed between first and second cell walls () and is capable of adopting, and being electrically latched between, at least two stable configurations. The layer of material () comprises one or more separate electrically addressable regions () and addressing means are provided to write to each of said electrically addressable regions using voltage pulses to selectively latch said layer of material as required. The addressing means is arranged to write to each of said one or more separate electrically addressable region using at least first and second latching scans. The first latching scan being arranged to selectively latch material having a latching threshold within a first range and said second latching scan being arranged to selectively latch material having a latching threshold within a second range, wherein said first latching scan is applied prior to application of said second latching scan and said second latching scan is insufficient to latch material having a latching threshold within said first range. A method for addressing a device is also disclosed.

Display device

A liquid crystal device is described that comprises a layer of liquid crystal material contained between a first cell wall and a second cell wall. The layer of liquid crystal material being switchable between at least a first state and a second state, said first state and said second state having sufficiently low splay to enable rapid electrical switching therebetween. The internal surface of said first cell wall is arranged to provide two or more surface alignment configurations of different pretilt to said layer of liquid crystal material. Said states may persist in the absence of an applied electric field. In particular, the invention relates to pi-cell devices that allow for rapid switching from the initial splay state to the bend states, and also to bistable or multistable pi-cell devices.

Liquid crystal device with bi- or multistable alignment gratings

This invention relates to a liquid crystal device wherein the surface profile of a surface alignment grating stabilizes at least one stable state. The invention involves the introduction or breaks () or discontinuities into the grating () to divide the grating into a plurality of groove segments. The breaks are discontinuities in the grating in the groove direction, the grating having substantially the same groove direction on each side of the break. The introduction of breaks prevent free movement of defects along the groove of the grating and therefore help to stabilize the desired liquid crystal configuration, either a Defect state or a Continuous state. Suitable breaks involve gaps () in the groove ridges (), necks () between the groove ridges () and slips or relative displacement () of the grating.

A method and apparatus for forming a patterned layer having a surface profile that provides relief structures within an electronic device. The method comprises the steps of taking a carrier film () having an inverse of the required surface profile formed on one side thereof, taking a layer of fixable material () located on a substrate (), laminating the carrier film () and substrate () such the carrier film causes the required surface profile to be formed in the layer of fixable material with a predetermined offset, and then fixing the fixable material. Lamination may be performed using rollers () or a vacuum process. The process is designed to ensure that the offset can be kept as low as possible, preferably to within 150 nm.

Embossing method and apparatus

This invention relates to a liquid crystal device with grey scale. The invention uses dither, either spatial or temporal. For spatial dither the invention arranges so that at least one bit of dither is not a multiple of the size of a smaller bit of dither&#x2014;in other words there is a fractional weighting. The two bits of dither have the same number of addressable transmission levels and the weighting sacrifices some linearity in exchange for reduction of manufacturing tolerances for the smaller bit. For temporal dither the invention relates to fractional weighting of the duration of the sub-frames.

Liquid crystal devices with greyscale

The invention is directed to liquid crystal compositions for use in bistable liquid crystal devices and to bistable liquid crystal devices containing said liquid crystal compositions. The liquid crystal composition comprises a component (&#x3c0;) said component (&#x3c0;) containing one or more compounds having a phenyl ring of formula A Whereby Xis F, CI, SF, NCS or a Cto Calkanyl, alkenyl or alkoxy radical substituted with at least one F atom; and Lis H or F. 

Liquid crystal composition for bistable liquid crystal devices

A repeated pattern layer having areas for imparting different electro-optic characteristics to a light modulating device is disclosed. The repeated pattern is arranged so that any pixel area formed in the assembled device (above a certain minimum size) will contain an area of each electo-optic characteristic in the right proportions. The pattern is arranged as a two dimensional grid of areas of different characteristic with at least one area of each characteristic provided in each row and column of the grid. The patterned layer may usefully be an alignment layer for a liquid crystal device, especially a bistable device, and the different areas may be arranged to give grey scale in the device.

Patterned light modulating device

Growing community of inventors

Malvern, United Kingdom

John Clifford Jones