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WO1997040418A1 - Systeme d'affichage - Google Patents

Systeme d'affichage Download PDF

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Publication number
WO1997040418A1
WO1997040418A1 PCT/GB1997/001160 GB9701160W WO9740418A1 WO 1997040418 A1 WO1997040418 A1 WO 1997040418A1 GB 9701160 W GB9701160 W GB 9701160W WO 9740418 A1 WO9740418 A1 WO 9740418A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
array
screen
lens
input
Prior art date
Application number
PCT/GB1997/001160
Other languages
English (en)
Inventor
William Alden Crossland
Anthony Bernard Davey
Vincent Glenn Geake
Ian David Springle
Original Assignee
The Secretary Of State For Defence
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by The Secretary Of State For Defence filed Critical The Secretary Of State For Defence
Priority to AU26451/97A priority Critical patent/AU2645197A/en
Priority to GB9822752A priority patent/GB2327769B/en
Publication of WO1997040418A1 publication Critical patent/WO1997040418A1/fr

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133617—Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/13356—Structural association of cells with optical devices, e.g. polarisers or reflectors characterised by the placement of the optical elements
    • G02F1/133562—Structural association of cells with optical devices, e.g. polarisers or reflectors characterised by the placement of the optical elements on the viewer side
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/66—Transforming electric information into light information
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/66—Transforming electric information into light information
    • H04N5/70—Circuit details for electroluminescent devices
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/74—Projection arrangements for image reproduction, e.g. using eidophor
    • H04N5/7416—Projection arrangements for image reproduction, e.g. using eidophor involving the use of a spatial light modulator, e.g. a light valve, controlled by a video signal
    • H04N5/7441—Projection arrangements for image reproduction, e.g. using eidophor involving the use of a spatial light modulator, e.g. a light valve, controlled by a video signal the modulator being an array of liquid crystal cells
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00—Details of colour television systems
    • H04N9/12—Picture reproducers

Definitions

  • This invention relates to display systems, and especially to liquid crystal display systems with phosphors, modulators for the systems and collimated light sources for these systems.
  • Liquid-crystal displays of the type discussed in this patent require a light source, preferably a collimated source, to achieve the phosphors.
  • a collimated backlight source is known from Zimmerman et al, SID Digest, vol LXXVI, 1995, Florida, p793.
  • An array of micro-optic elements is bonded to one side of a light pipe. Light is coupled from the light pipe at the points of contact with the micro-optic elements, reflected inside the elements with total internal reflection and refracted at the top surface of the elements to provide total collimated light. This is a fairly elaborate arrangement.
  • liquid-crystal device is a polymer-dispersed liquid-crystal (PDLC) display device.
  • PDLC devices rely on the mismatch between the refractive index of a polymer and the "extraordinary" refractive index of the liquid-crystal molecules in the unpowered state. In this state the mismatch generates scattering. It is usually arranged that in the powered state the liquid crystal has an "ordinary" refractive index which matches that of the surrounding polymer, so that normally incident light is not scattered and passes directly through the cell. This cell suffers the flaw that at other angles of incidence there is a refractive index mismatch between the polymer and the liquid crystal, which increases as the angle of incidence becomes further and further from normal, causing slight scattering known as haze.
  • a modulator for modulating input collimated light comprising at least one switchable beam- deflecting device, at least one lens and at least one secondary output means which emits secondary light when input light is directed towards it through the lens, m which the beam-deflecting device is so arranged as, in one of its switching states, substantially to prevent the input light from reaching the secondary output means.
  • the modulator makes use of a spatial filtering technique in which light is focused to a point and a pinhole screen is placed at this point.
  • the beam-deflecting device is of the kind which can be switched between a scattering and a clear state and is placed in the path of the beam before the pinhole; when it is switched to scattering it prevents almost all the light from passing through the pinhole.
  • spatial filters as such are known, their use m displays is limited because they require the input of collimated light, and for a reasonably viewable display their output then needs to be "de- collimated" , or broadened / for instance by means of a diffusing plate.
  • the diffusion of the output light is performed automatically by the secondary emitters.
  • the input light is monochromatic or at least of a narrow range of wavelengths, for instance UV light at 365 nm
  • the secondary output means is an emitter comprising a photoluminescent dot emitting visible light when struck by UV.
  • the dot can be arranged on a partially transparent substrate such as a glass plate, and re-emits light at a frequency that is passed by the glass plate, the glass plate absorbing light at other frequencies, advantageously including the frequency of the incident light.
  • the use of such narrow-band input light overcomes another disadvantage inherent in the prior art, namely the problems of using white-light sources. Such sources lead to chromatic aberration in the lens and difficulties in matching the characteristics of the liquid crystal for all wavelengths. When near- monochromatic input light is used these disadvantages are eliminated, while still allowing a colour display to be constructed.
  • the secondary emitter may comprise a plate with an aperture and a photoluminescent screen provided in front of the plate so that light passing through the lens and then the aperture is incident on the screen and re-emitted.
  • a photoluminescent screen provided in front of the plate so that light passing through the lens and then the aperture is incident on the screen and re-emitted.
  • the photoluminescence of the dot or screen is preferably afforded by a phosphor material, e.g. RGB phosphors, though other effects such as photochromic modulation can be used.
  • the function of the lens which is to be understood as any suitable kind of focusing means, is to concentrate the input light to a small "target" volume of space, for instance the phosphor dot or the aperture, so that any diversion of the incoming light by the deflecting device has the effect of causing substantially the entire beam to miss the target.
  • a kind of "spatial filtering" can be performed.
  • the beam-deflecting device can be, for instance, a liquid crystal of the scattering type; it is then not necessary for the liquid crystal to block the incoming light. This renders such efficiency-reducing accessories as polarisers unnecessary.
  • the switchable beam-deflecting device may be a switchable liquid-crystal grating. If a scattering liquid-crystal device is used it may be a polymer- dispersed liquid-crystal device (PDLC) . Alternatively nematic-cholesteric phase transition or smectic-A scattering devices may perform the beam deflection.
  • PDLC polymer- dispersed liquid-crystal device
  • an array of switchable beam-deflecting devices an array of lenses, for example a micro-lens array, and a photoluminescent screen with an array of predetermined areas that re- emit light, for instance an array of photoluminescent dots on a glass plate or a plate with an array of pinholes and a single photoluminescent screen mounted in front of the plate.
  • an array of switchable beam-deflecting devices an array of lenses, for example a micro-lens array
  • a photoluminescent screen with an array of predetermined areas that re- emit light, for instance an array of photoluminescent dots on a glass plate or a plate with an array of pinholes and a single photoluminescent screen mounted in front of the plate.
  • the invention is further directed to a system comprising a collimated light source and a modulator as described above.
  • the collimated light source preferably emits in a narrow wave-band.
  • the light source is an ultra-violet light source though lower-wavelength visible light is also conceivable.
  • the collimated light source may be similar to the light source described in Zimmerman et al (see above) .
  • the light source may include at least one point source of light and at least one source lens aligned with the point source or sources, the focal point of this lens being approximately at the point source of light.
  • the point source may be a physically small light source such as an LED or a small-section high-pressure mercury arc, or it may be an enclosed light source with a pinhole aperture. In the latter case it can be formed from at least one UV strip light in a reflecting cavity with at least one pinhole punched in the front face of the cavity.
  • an array of point sources is provided using an array of pinholes, and perhaps also an array of strip lights.
  • Another method of providing a point source is to provide at least one ultra-violet bulb in a reflecting cavity, with at least one small photoluminescent dot on the front face of the cavity that absorbs the light via an aperture and retransmits it.
  • the point source is then the photoluminescent dot.
  • the ultra-violet bulbs can emit light at 254nm
  • the photoluminescent dots can absorb this 254nm light and emit light at 365nm.
  • the photoluminescent dot is preferably a phosphor.
  • a further possibility for producing a point source is the use of a high-pressure arc lamp and an elliptical reflector to focus the light onto a pinhole. Arrays of these point sources can then be built up.
  • an array of lenses may be provided by a micro-lens array, particularly in small-scale systems, or an array of individual lenses, which is more suitable for large- scale displays.
  • a further aspect of the invention is therefore a small- to medium-scale display system comprising a collimated narrow-band activating light source and a modulator comprising an LCD array, a micro-lens array, a pinhole array and an output screen sensitive to the activating light.
  • the modulator may comprise an LCD array, a micro-lens array and an array of output elements such as phosphor dots on the inside of a glass screen.
  • the collimated source may be for example that described above or the backlight system described in the prior art document of Zimmerman et al.
  • Another aspect of the invention is a large-scale public annunciator system or stadium display system comprising a UV backlight source and pixel tubes containing angular discrimination means and secondary display elements.
  • Each pixel of the display may comprise a self- contained tube containing an individual collimating UV light source and an individual modulator.
  • parts of the system may be shared between pixels, for example the collimating UV backlight system.
  • a method of modulating collimated activation light comprising passing the light through a switchable beam deflector that can be switched to pass light in one state or to scatter or deflect light in another state, the light then passing through a focusing means and a screen responsive to the activation light and arranged so that undisturbed light is focused by the focusing means onto a predetermined part of the screen that re-emits light and scattered light falls on other parts of the discriminator and is absorbed or reflected.
  • the modulator may be used to form a light valve for use in display or lighting systems.
  • This invention reduces the disadvantage of prior- art PDLC systems because the collimated light from the source passes normally through the liquid-crystal cells, which substantially eliminates haze.
  • the chromatic aberration which may cause considerable discoloration of white light and may also reduce the contrast and/or brightness of the display, may also be substantially eliminated by the use of substantially monochromatic, preferably UV, light. This light can be rendered visible, in terms both of colour and of viewing angle, by the photoluminescent screen.
  • Figures 1(a) and (b) show the principle of the angular discriminator idea combined with the secondary- emitter structure, in accordance with the invention
  • Figure 2 shows an element of a large-scale modular display representing a first embodiment of the invention
  • Figures 3 and 4 show a variant similar to the embodiment of Figure 2 ,-
  • Figures 5, 6 and 7 show a second embodiment of the invention
  • Figure 8 shows a variant of the second embodiment
  • Figures 9 and 10 show an experimental setup without and with spatial filtering
  • FIG 11 shows an embodiment of the invention using the setup of Figure 10.
  • Figure 1 shows a generalised form of the device of the invention.
  • the scattering liquid crystal device in this embodiment is a polymer-dispersed liquid-crystal device PDLC.
  • PDLC polymer-dispersed liquid-crystal device
  • the liquid crystal has a refractive index mismatch with the surrounding polymer of the PDLC and scatters the light.
  • Figure 1(b) shows the on state.
  • the refractive index of the liquid crystal matches that of the surrounding polymer, and the light passes unscattered through the element.
  • the first specific embodiment is a large-scale public annunciator or stadium display, one element of which is shown in Figure 2.
  • Each pixel of the display is made from an individual tube 20 that screws into a rack via a fitting 22, and a back board is provided containing the electrical connections to each pixel.
  • Each tube contains its own collimated light source.
  • a UV-producing arc lamp 24 is provided inside an elliptical reflector 26 which focuses the light from the bulb to a small spot at a pinhole 27.
  • a filter 28 placed in front of the reflector filters out the visible light.
  • the light emerging from the hole is collimated by a lens 30, and passes through a scattering-type liquid-crystal device 32. After that, if the light is not scattered it passes through an angular discrimination lens 34 and another pinhole 36 at the focal point of the lens, finally falling on a glass or plastic front screen 40 coated in photoluminescent material such as a phosphor, or a photochromic material.
  • the same principle is used in the second embodiment, shown in Figures 3 and 4, in which the light source, a mercury discharge tube, is common to several pixel tubes.
  • the light source comprises a UV strip light 50 inside a reflective cavity.
  • the front face of the cavity comprises many small apertures 52 from which light escapes.
  • a pixel tube 54 is mounted in front of each aperture 52, screwed into the backplane 60.
  • the pixel tubes comprise the collimating lens 56, the liquid-crystal shutter 58 and the angular discrimination device.
  • the third embodiment illustrated in an exploded view in Figure 5, is an embodiment suitable for use in a small-scale public annunciator or a television-style display.
  • UV light from discharge tubes 70 around the edge of a waveguide 71 is collimated by a film 72 as in the Zimmerman device described above.
  • the collimated beams pass through a plurality of liquid-crystal scattering shutters 74 comprising glass layers 74A, 74C sandwiching a scattering liquid crystal 74B, and then a microlens array 76 aligned with the shutters.
  • a spacing layer 78 holds a sheet of glass in the focal plane of the lenses.
  • a small photoluminescent dot 82 is placed at the focal point of each lens, on a glass sheet 80.
  • Fig. 6 shows a sectional detail through the upper part of this arrangement
  • Fig. 7 is a corresponding perspective view.
  • FIG. 8 The variant embodiment shown in Figure 8 is the same as the version shown in Figs. 5-7 except that the phosphor dots are replaced by pinholes 90.
  • a more or less uniform photoluminescent screen 92 is mounted beyond the pinholes, spaced apart by a second spacing layer 94 at a distance such that light passing through one pinhole does not cause the screen to emit secondary light at a location corresponding to an adjacent pinhole.
  • FIGS 9, 10 and 11 illustrate the principle and an embodiment of the invention.
  • a polymer dispersed liquid crystal (PDLC) test device 1 was normally illuminated with a 2mm diameter beam from a HeNe laser 21 as shown in Figure 9. The light emerging from the cell was collected and focused upon the active area of a photodiode detector 31 using a 2cm diameter lens 25 placed 150mm behind the PDLC device.
  • the PDLC device was fabricated in the usual way using a mixture of TL205 nematic liquid crystal and PN393 reactive mesogen.
  • the cell gap was nominally lO ⁇ m, and the ITO pattern defined a single 1cm 2 pixel.
  • the PDLC device When non-powered the PDLC device was translucent and scattered light. With the application of a 20V rms sin wave the pixel became clear and allowed light to pass through the cell without significant scattering.
  • a spatial filter arrangement was inserted between the PDLC device 1 and the detection lens 25 as shown in Figure 10.
  • the spatial filter was composed of a 20x microscope objective 3, a 20 ⁇ m diameter pin hole screen 5 and a collimating lens 23.
  • the objective, pin hole and collimating lens (which were all mounted on translation stages) , were carefully adjusted to be concentric with the incident laser beam, in such a way that the maximum amount of light passed through the pinhole and the emerging light was collimated into a beam of approximately 10mm in diameter.
  • the detector was illuminated with 86.5% of the light which was collected with the clear PDLC in the initial configuration ( Figure 1) .
  • the ratio of clear signal to scattering signal was 618:1, which represents the contrast that could be obtained in a PL-LCD if the phosphor screen were placed at the position of the collection lens 25.
  • the phosphor screen could be placed anywhere after the pin hole, with the elimination of the collimating lens 23.
  • Figure 11 shows an arrangement of the latter type.
  • a collimated UVA source comprised a 0.25x0.25mm Hg arc lamp 39, a parabolic reflector 37, a 50 ⁇ m pin hole 45, lenses 41,43,47 and a filter 49. It was used to illuminate a PDLC device 1.
  • the beam diameter was 4mm.
  • a 30mm diameter lens 3 (Melles Griot LA0124) , was placed 50mm behind the PDLC device, followed by a 0.5mm pin hole 5 and a phosphor screen 9,11.
  • the pin hole was 97mm from the front face of the lens 3.
  • the PDLC device was the same as described in Fig. 9, and it was driven the same way.
  • the phosphor screen was formed by depositing P22B phosphor powder (ZnS;Ag, 6.5 ⁇ m mean diameter particles), onto a glass substrate using a settling method with Barium Chloride and Potassium Silicate solutions.
  • the components of the apparatus were aligned on an optical bench so that all components were concentric with the UV illumination.
  • With the PDLC device in the clear state a green emission from the screen could easily be seen under ambient lighting conditions. When in the scattering state the green emission could not be seen easily.
  • the ratio of flux emitted by the phosphor with the clear PDLC to the flux emitted with the scattering PDLC was 125:1. In the clear state 92% of the light emerging from lens 3 subsequently emerged from the far side of the pin hole 5.
  • a more practical implementation of this architecture would integrate the spatial filter used to discriminate the switched light with the spatial filter used to collimate the arc lamp's emissions. This would reduce the lens count from four to two.

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  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Devices For Indicating Variable Information By Combining Individual Elements (AREA)
  • Liquid Crystal (AREA)

Abstract

Un modulateur permettant de moduler la lumière collimatée d'entrée, notamment les U.V., utilise un dispositif de filtration spatial pour diriger ladite lumière sur des émetteurs fluorescents. Pour ce faire, il comprend au moins un dispositif de déviation de faisceau commutable, tel qu'un afficheur à cristaux liquides de dispersion (1), au moins une lentille (3) et au moins un système de sortie secondaire, tel qu'un écran fluorescent (9, 11), qui émet de la lumière visible quand la lumière d'entrée est dirigée sur lui par la lentille. Le dispositif de déviation (1) est configuré de façon que, dans son état de dispersion, il empêche sensiblement la lumière d'entrée d'atteindre le système de sortie secondaire, ce qui produit une sortie sombre, tandis que dans son autre état (état clair), la lumière U.V. traverse le trou (5) et atteint le phosphore (11).
PCT/GB1997/001160 1996-04-25 1997-04-25 Systeme d'affichage WO1997040418A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU26451/97A AU2645197A (en) 1996-04-25 1997-04-25 Display system
GB9822752A GB2327769B (en) 1996-04-25 1997-04-25 Display system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB9608541.0A GB9608541D0 (en) 1996-04-25 1996-04-25 Display system
GB9608541.0 1996-04-25

Publications (1)

Publication Number Publication Date
WO1997040418A1 true WO1997040418A1 (fr) 1997-10-30

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1997/001160 WO1997040418A1 (fr) 1996-04-25 1997-04-25 Systeme d'affichage

Country Status (3)

Country Link
AU (1) AU2645197A (fr)
GB (2) GB9608541D0 (fr)
WO (1) WO1997040418A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000014598A1 (fr) * 1998-09-04 2000-03-16 Screen Technology Limited Dispositif fluorescent pour affichage a cristaux liquides
WO2000017700A1 (fr) * 1998-09-21 2000-03-30 Screen Technology Limited Montage optique pour ecrans plats
WO2002075440A1 (fr) * 2001-03-21 2002-09-26 Screen Technology Limited Affichage a cristaux liquides photoluminescent
WO2004109225A1 (fr) * 2003-06-05 2004-12-16 Universität Stuttgart Agencement de sources lumineuses ponctuelles commutable et son utilisation en interferometrie

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62194228A (ja) * 1986-02-20 1987-08-26 Matsushita Electric Ind Co Ltd 発光型表示装置
WO1991008508A1 (fr) * 1989-11-24 1991-06-13 Innovare Limited Dispositif d'affichage
JPH04350693A (ja) * 1991-05-28 1992-12-04 Clarion Co Ltd ディスプレイ装置
JPH05313154A (ja) * 1992-05-06 1993-11-26 Mitsubishi Electric Corp 液晶ディスプレイ装置
WO1995027920A1 (fr) * 1994-04-06 1995-10-19 Screen Technology Limited Ecran d'affichage

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62194228A (ja) * 1986-02-20 1987-08-26 Matsushita Electric Ind Co Ltd 発光型表示装置
WO1991008508A1 (fr) * 1989-11-24 1991-06-13 Innovare Limited Dispositif d'affichage
JPH04350693A (ja) * 1991-05-28 1992-12-04 Clarion Co Ltd ディスプレイ装置
JPH05313154A (ja) * 1992-05-06 1993-11-26 Mitsubishi Electric Corp 液晶ディスプレイ装置
WO1995027920A1 (fr) * 1994-04-06 1995-10-19 Screen Technology Limited Ecran d'affichage

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
LEWIS M F ET AL: "The use of lenslet arrays in spatial light modulators", MICROLENS ARRAYS TOPICAL MEETING, TEDDINGTON, UK, 12-14 MAY 1993, vol. 3, no. 2, ISSN 0963-9659, PURE AND APPLIED OPTICS, MARCH 1994, UK, pages 143 - 150, XP000444758 *
PATENT ABSTRACTS OF JAPAN vol. 12, no. 46 (P - 665) *
PATENT ABSTRACTS OF JAPAN vol. 17, no. 215 (P - 1527) *
PATENT ABSTRACTS OF JAPAN vol. 18, no. 126 (P - 1702) *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000014598A1 (fr) * 1998-09-04 2000-03-16 Screen Technology Limited Dispositif fluorescent pour affichage a cristaux liquides
WO2000017700A1 (fr) * 1998-09-21 2000-03-30 Screen Technology Limited Montage optique pour ecrans plats
WO2002075440A1 (fr) * 2001-03-21 2002-09-26 Screen Technology Limited Affichage a cristaux liquides photoluminescent
WO2004109225A1 (fr) * 2003-06-05 2004-12-16 Universität Stuttgart Agencement de sources lumineuses ponctuelles commutable et son utilisation en interferometrie

Also Published As

Publication number Publication date
GB2327769A8 (en) 1999-02-18
GB9822752D0 (en) 1998-12-16
GB2327769A (en) 1999-02-03
GB2327769B (en) 2000-10-04
GB9608541D0 (en) 1996-07-03
AU2645197A (en) 1997-11-12

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