Cambridge Enterprise Limited

Qinetiq Limited

Dow Corning Corporation

Thomas Swan & Co. Limited

Samsung Electronics Co., Ltd.

Candescent Technologies Corporation

Cambridge University Technical Services Limited

Candescent Intellectual Property Services, Inc.

Two Trees Photonics Limited

Holographic Imaging LLC

Cambridge Enterprise Limited University of Cambridge

Advex Corporation Limited

William Alden Crossland

Neil Collings

Daping Chu

Brian Robertson

Timothy David Wilkinson

Anthony Bernard Davey

Huan Xu

Terry Clapp

Jonathan Hannington

John Richard Moore

Maura Michelle Redmond

Russell Keith King

Martin Grasmann

Fumito Nishida

Timothy M Coker

Omar Farooq

Jamieson Christmas

Adrian James Cable

Melanie Holmes

Harry J Coles

Nicholas A Lawrence

Mykhaylo Pivnenko

Edward Buckley

Peter Mash

Andreas Georgiou

Maura Redmond

Ilias Manolis

Jinsong Liu

Oliver Hadeler

Hoon Song

Hong-seok Lee

Theodore S Fahlen

Joo-Nyung Jang

Robert M Duboc

Christopher J Curtin

Kim Leong Tan

Dackson Masiyano

Trevor Hall

Gang Sun

David Nugent

Steven Robson

Tat C B Yu

Timothy Martin Coker

Marua Michelle Redmond

Jhen Si Chen

Mikhael Pivnenko

Russel Keith King

Steven Warr

Tat Cb Yu

Anthony B Davey

Alan Colin Dixon

Jonathan Paul Hannington

Trevor James Hall

Anthony Bemard Davey

Mike Pivnenko

Martin Grassman

Harry James Coles

An imaging device includes a projection optic arranged to form a virtual image of an object. The imaging device further includes a first diffuser positioned a first distance from the virtual projection optic and a second diffuser positioned a second distance from the virtual projection optic. The controller is arranged to control the first and second diffuser to make the real image visible on one of the diffusers.

Imaging device for moving a virtual image

A LCOS routing device, comprising: an optical input and plurality of optical outputs; a spatial light modulator (SLM) between said input and output, for displaying a kinoform; a data processor, configured to provide kinoform data for displaying said kinoform on said SLM. Said data processor inputs routing and calculates said kinoform data. Said data processor calculates kinoform data by: determining an initial phase pattern for said kinoform; calculating a replay field of said phase pattern; modifying an amplitude component of said replay field, retaining a phase component of said replay field to provide an updated replay field; performing a space-frequency transform on said updated replay field to determine an updated phase pattern for said kinoform; and repeating said calculating and updating of said replay field and said performing of said space-frequency transform until said kinoform for display is determined; and outputting said kinoform data for display on said LCOS SLM.

Apparatus and methods for light beam routing in telecommunication

This invention relates to methods and apparatus for routing light beams in telecommunications devices using holographic techniques, in particular by displaying kinoforms on Liquid Crystal on Silicon devices. At least one optical input to receives an input beam. A plurality of optical outputs and a spatial light modulator (SLM) on an optical path between said optical input and said optical outputs are provided, and a driver for said SLM to display a kinoform on said SLM diffracts said input beam into an output beam comprising a plurality of diffraction orders, wherein a routed one of said diffraction orders is directed to at least one selected said optical output; said apparatus is configured to modify a wavefront of said output beam to reduce a coupling of said output beam into said selected optical output; and said kinoform is adapted to compensate for said wavefront modification to compensate for said reduced coupling.

Optical beam routing apparatus and methods

We describe a LCOS (liquid crystal on silicon) telecommunications light beam routing device, the device comprising: an optical input; a plurality of optical outputs; a LCOS spatial light modulator (SLM) in an optical path between said input and said output, for displaying a kinoform; a data processor, coupled to said SLM, configured to provide kinoform data for displaying said kinoform on said SLM; wherein said kinoform data defines a kinoform which routes a beam from said optical input to a selected said optical output; wherein said data processor is configured to input routing data defining said selected optical output and to calculate said kinoform data for routing said beam responsive to said routing data; and wherein said data processor is configured to calculate said kinoform data by: determining an initial phase pattern for said kinoform; calculating a replay field of said phase pattern; modifying an amplitude component of said replay field to represent a target replay field for said beam routing, retaining a phase component of said replay field to provide an updated replay field; performing a space-frequency transform on said updated replay field to determine an updated phase pattern for said kinoform; and repeating said calculating and updating of said replay field and said performing of said space-frequency transform until said kinoform for display is determined; and outputting said kinoform data for display on said LCOS SLM.

In a driver for a smectic-A composition liquid crystal panel, the driver forms a resonant circuit operable to oscillate at resonant frequency for ordering the smectic-A liquid crystal composition of the panel.

Driver circuit

This invention relates to methods and apparatus for routing light beams in telecommunications devices using holographic techniques, in particular by displaying kinoforms on LCOS (Liquid Crystal on Silicon) devices. Thus we describe optical beam routing apparatus comprising: at least one optical input to receive an input beam; a plurality of optical outputs; a spatial light modulator (SLM) on an optical path between said optical input and said optical outputs; and a driver for said SLM to display a kinoform on said SLM to diffract said input beam into an output beam comprising a plurality of diffraction orders, wherein a routed one of said diffraction orders is directed to at least one selected said optical output; wherein said apparatus is configured to modify a wavefront of said output beam to reduce a coupling of said output beam into said selected optical output; and wherein said kinoform is adapted to compensate for said wavefront modification to compensate for said reduced coupling and thereby to reduce a coupling of other diffracted light from said input beam into others of said optical outputs than said at least one selected optical output.

Provided are an optically addressable spatial light modulator (OASLM) divided into a plurality of segments, and an apparatus and method for displaying a holographic three-dimensional (3D) image using the OASLM. The holographic 3D image display apparatus includes a first light source which emits a write beam, an electric addressable spatial light modulator (EASLM) which modulates the write beam emitted from the first light source according to hologram information regarding a 3D image, a second light source which emits a read beam, an OASLM which receives the write beam modulated by the EASLM and modulates the read beam emitted from the second light source according to hologram information included in the modulated write beam, a scanning optical unit which projects the write beam modulated by the EASLM onto the OASLM, and a Fourier lens which focuses the read beam modulated by the OASLM onto a predetermined space to form the 3D image.

Optically addressable spatial light modulator divided into plurality of segments, and holographic three-dimensional image display apparatus and method using the light modulator

The invention relates to optical beam steering. There is described an optical beam steering apparatus, comprising: a splitter arranged to split an optical beam into at least a first part having a first polarization and a second part having a second polarization, said first and second polarizations being substantially mutually orthogonal; a first liquid crystal device region arranged to receive said first part and to have director orientation substantially aligned to said first polarization; and a second liquid crystal device region arranged to receive said second part and to have director orientation substantially aligned to said second polarization.

Optical beam steering

A liquid crystal smectic A composition that can be switched by the application of different electric fields across it between a first stable state (left hand block in FIG.) and at least one second stable state (right hand block in FIG.) in which the composition is less ordered than in the first state. The radiation transmission properties of the first and second states are different. The composition comprises: (A) a liquid crystal material that has a positive dielectric anisotropy and that is a uniformly aligned smectic A structure when in the first state; (B) an ionic dopant giving a negative conductivity anisotropy in the liquid crystal material so that it is capable of disrupting the smectic A structure of the first state when subject to an electric field that causes the dopant to migrate through the composition, thereby causing the composition to switch into said at least one second state, and (C) optically anisotropic pigment particles having positive dielectric anisotropy dispersed in the composition, the largest dimension of the pigment particles being in the range of 10 nm to 1 &#x3bc;m. The composition, when in the first relatively stable state, is capable of undergoing smectic dynamic scattering due to electro-hydrodynamic instability under the influence of a sufficiently low frequency AC field, thereby disordering the liquid crystals and the pigment particles and thereby discouraging the pigment particles from aggregating together. The composition is suitable for use in displays and is especially resistant to degradation by ambient light and so can be used in outside applications.

Smectic A compositions for use in optical devices

The present, invention relates to liquid crystal compositions having a smectic A structure for use in an optical device in which the composition is sandwiched between a pair of electrodes (-). In essence the composition includes a siloxane oligomer (component (a)) which may be seen to construct a layered SmA system of particular spacing and 'strength'. Within this structure a low molar mass nematic mesogen (component (c)) is provided that may be considered to be that of a 'plasticiser' which moderates the layer &#x201c;strength&#x201d;, while simultaneously providing tuneability to the properties of the composition, e.g. its refractive index or dielectric anisotropy. The addition of a side chain liquid crystal polysiloxane (component (d)) allows such systems to be further moderated since they can be considered as binding together the la&#x3e;&#xbe;rs, both within a given layer and between layers. An ionic dopant (component (b)) is also included in the composition that migrates through the composition when low frequency electric fields are applied to the composition by the electrodes, thereby disrupting the order to the composition. Order in the composition can be restored by applying a higher frequency field that does not allow the dopant time to migrate significantly. Chromophores may also be included in the formulation.

Liquid crystal formulations and structures for smectic A optical devices

A method of displaying a video image comprises receiving sequential image frames at a processor. Each image frame is processed to obtain a kinoform. A programmable diffractive element such as an SLM represents the sequence of kinoforms allowing reproduction of the image using a suitable illumination beam.

Apparatus and method for displaying a video image

A liquid crystal formulation is described. The liquid crystal formulation comprises a first oligosiloxane-modified nano-phase segregating liquid crystalline material; and at least one additional material selected from a second oligosiloxane-modified nano-phase segregating liquid crystalline material, non-liquid crystalline oligosiloxane-modified materials, organic liquid crystalline materials, or non-liquid crystalline materials, wherein the liquid crystal formulation has an I&#x2192;SmA*&#x2192;SmC* phase transition, with a SmC* temperature range from about 15&#xb0; C. to about 35&#xb0; C., a tilt angle of about 22.5&#xb0;&#xb1;6&#xb0; or about 45&#xb0;&#xb1;6&#xb0;, a spontaneous polarization of less than about 50 nC/cm2., and a rotational viscosity of less than about 600 cP. Devices containing liquid crystal formulations are also described. The device has a stable bookshelf geometry, bistable switching, and isothermal electric field alignment, a response time of less than 500 &#x3bc;s when switched between two stable states, and an electric drive field of less than about 30 V/&#x3bc;m.

Oligosiloxane modified liquid crystal formulations and devices using same

A liquid crystal formulation is described. The liquid crystal formulation comprises a first oligosiloxane-modified nano-phase segregating liquid crystalline material; and at least one additional material selected from a second oligosiloxane-modified nano-phase segregating liquid crystalline material, non-liquid crystalline oligosiloxane-modified materials, organic liquid crystalline materials, or organic non-liquid crystalline materials, wherein the liquid crystal formulation is nano-phase segregated in the SmC* phase, has an I&#x2192;SmC* phase transition, with a SmC* temperature range from about 15&#xb0; C. to about 35&#xb0; C., has a tilt angle of about 22.5&#xb0;&#xb1;6&#xb0; or about 45&#xb0;&#xb1;6&#xb0;, and has a spontaneous polarization of less than about 50 nC/cm2, and a rotational viscosity of less than about 600 cP. Devices containing liquid crystal formulations are also described. The device has a stable bookshelf geometry, bistable switching, and isothermal electric field alignment, a response time of less than 500 &#x3bc;s when switched between two stable states, and an electric drive field of less than about 30 V/&#x3bc;m.

A method of retrieving phase information from input intensity information, representative of a target image, in which a Fourier transform is performed on data and the result used in forming a phase estimate, the phase estimate being inverse Fourier transformed, thereby producing magnitude and phase replay, and wherein not only is the phase reply component but also data derived from the magnitude replay component, iteratively fed back.

Phase retrieval and phase hologram synthesis

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Cambridge, United Kingdom

William Alden Crossland