WO1996006380A2 - Dispositif d'affichage a cristaux liquides et feuille retardatrice - Google Patents

Dispositif d'affichage a cristaux liquides et feuille retardatrice Download PDF

Info

Publication number
WO1996006380A2
WO1996006380A2 PCT/IB1995/000644 IB9500644W WO9606380A2 WO 1996006380 A2 WO1996006380 A2 WO 1996006380A2 IB 9500644 W IB9500644 W IB 9500644W WO 9606380 A2 WO9606380 A2 WO 9606380A2
Authority
WO
WIPO (PCT)
Prior art keywords
optically anisotropic
anisotropic layer
liquid crystal
layer
display device
Prior art date
Application number
PCT/IB1995/000644
Other languages
English (en)
Other versions
WO1996006380A3 (fr
Inventor
Johannes Albertus Matthijs Maria Van Haaren
Dirk Jan Broer
Original Assignee
Philips Electronics N.V.
Philips Norden Ab
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 Philips Electronics N.V., Philips Norden Ab filed Critical Philips Electronics N.V.
Priority to EP95926478A priority Critical patent/EP0725943B1/fr
Priority to JP50790596A priority patent/JP3358815B2/ja
Priority to DE69530751T priority patent/DE69530751T2/de
Publication of WO1996006380A2 publication Critical patent/WO1996006380A2/fr
Publication of WO1996006380A3 publication Critical patent/WO1996006380A3/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
    • 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
    • G02F1/13363—Birefringent elements, e.g. for optical compensation
    • G02F1/133636—Birefringent elements, e.g. for optical compensation with twisted orientation, e.g. comprising helically oriented LC-molecules or a plurality of twisted birefringent sublayers
    • 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
    • G02F1/13363—Birefringent elements, e.g. for optical compensation
    • G02F1/133632—Birefringent elements, e.g. for optical compensation with refractive index ellipsoid inclined relative to the LC-layer surface

Definitions

  • Liquid crystal display device and retardation foil Liquid crystal display device and retardation foil.
  • the invention relates to a liquid crystal display device having a display cell which comprises a layer of nematic liquid crystal material between two substrates provided with electrodes, said cell being further provided with polarizers and comprising at least an optically anisotropic layer of a material having a cholesteric ordering between the polarizers.
  • the invention also relates to a liquid crystal display device having a display cell which comprises a layer of nematic liquid crystal material between two parallel substrates provided with electrodes, said cell being further provided with polarizers and comprising at least an optically anisotropic layer of polymer material between the polarizers.
  • the invention further relates to retardation foils for use in liquid crystal display devices. Display devices of this type are generally used in, for example monitors,
  • TV applications and, for example display devices in automobiles and for instruments.
  • a display device of the type described in the opening paragraph is known from USP 5,210,630.
  • a compensation foil consisting of an optically anisotropic layer of polymer material with a cholesteric ordering is used to inhibit discoloration and obtain a high contrast in a twisted nematic display device.
  • the polymer material is ordered in such a way that a molecular helix can be distinguished, with the axis of the helix being directed transversely to the layer.
  • a first display device comprising a liquid crystal display cell with a layer of nematic liquid crystal material which is present between two substrates provided with electrodes and comprises polarizers and at least an optically anisotropic layer of a material having a cholesteric ordering between the polarizers is therefore characterized in that, viewed transversely to the substrates, the director profile in the optically anisotropic layer has a non-rotationally symmetrical pattern. This can be ascertained by means of conoscopy.
  • the phrase "director profile in the optically anisotropic layer” is understood to mean the director profile across a thickness of at least an entire height or pitch of the molecular helix.
  • Non-rotationally symmetrical is herein understood to mean a pattern which does not exhibit any rotational symmetry and in which the finite thickness of the layer is not taken into consideration.
  • the pattern may be symmetrical with respect to an arbitrary axis. In this application this will also be referred to as “broken (axial) symmetry". Due to this measure, the optical axis of the optically anisotropic layer extends at an angle to the axis transverse to the two substrates.
  • the optical axis is herein understood to mean the direction having the smallest refractive index. In the above-mentioned polymer material having a molecular helix, the optical axis coincides with the axis of the helix.
  • a second display device comprising a liquid crystal display cell with a layer of nematic liquid crystal material which is present between two parallel substrates provided with electrodes and comprises polarizers and at least an optically anisotropic layer of a polymer material between the polarizers is characterized in that the optical axis of the optically anisotropic layer extends at an angle to a direction transverse to the substrates. In this case the optical axis need not have the same direction throughout the thickness of the anisotropic layer.
  • the invention is based on the recognition that in practice and at the customary voltage across the liquid crystal material, the directors in this material still extend at a small angle to the direction transverse to the substrates. Consequently, the birefringence for different viewing angles is different and is not symmetrical with respect to a direction perpendicular to the two substrates, which accounts for the angle dependence of a liquid crystal having a nematic structure. It is true that this angle dependence may be reduced by means of a compensation foil; however, when a compensation foil is used in the device as described above, in which the axis of the helix is directed transversely to the polymer layer, the compensation is optimal for an isotropic liquid crystal layer, i.e. a situation in which the directors are directed perpendicularly to the substrates. In practice, this situation occurs only at very high voltages (still disregarding the fact that the molecules are anchored on the substrates in such a way that this is impossible close to the substrates).
  • the angle dependence of the total device is changed in such a way that light beams which have undergone a large birefringence in the liquid crystal (at a given drive voltage, the "given voltage”) are more compensated by the birefringence in the compensation layer than light beams which have undergone a small birefringence in the liquid crystal.
  • the optical axis in the compensation layer is now substantially parallel to the average direction of the directors in the layer of liquid crystal material.
  • This "broken symmetry" can be adapted in given implementations of the invention.
  • the "given voltage” is preferably chosen to be such that the described compensation of birefringence occurs in a near-zero transmission range; for example, the voltage in the voltage/transmission characteristic at which 10% of the maximum transmission occurs is used for this purpose.
  • a "broken symmetry" transverse to the substrates can be obtained by providing a compensation foil as described in USP 5,210,630 at an angle to these substrates.
  • This embodiment is characterized in that the director profile in the optically anisotropic layer is parallel to boundary surfaces of the optically anisotropic layer, and the optically anisotropic layer is provided at an angle to one of the substrates.
  • the liquid crystal display device comprises as an optically anisotropic layer a layer of polymerized discotic liquid crystal materials.
  • discotic liquid crystal materials are given in "Discotic Liquid Crystal", Liquid Crystals 1993, vol. 14, no. 1, pp. 3-14.
  • Such a display device is characterized in that the average direction of the director in the optically anisotropic layer is transverse to the boundary surfaces of the optically anisotropic layer, and the optically anisotropic layer is provided at an angle to one of the substrates. In this case, the direction of the director coincides with the optical axis. In both cases, said angle is between 1 and 30 degrees and is preferably approximately 10 degrees.
  • a preferred embodiment of the display device according to the invention with a cholesteric ordering in the anisotropic layer, is therefore characterized in that the director profile in at least a part of the optically anisotropic layer is provided at an angle to the substrates.
  • a preferred embodiment of the display device according to the invention, with polymerized discotic liquid crystal materials in the anisotropic layer is characterized in that the director profile in at least a part of the optically anisotropic layer is provided at an angle to the direction transverse to the substrates.
  • the optically anisotropic layer preferably has a sawtooth structure on at least one of its boundary surfaces. In a device using a plurality of pixels, the pitch of the sawtooth structure is preferably of the order of the pixel size, or smaller.
  • the two boundary surfaces are formed with a sawtooth structure
  • the sawtooth directions i.e. the directions in which the separate teeth increase in thickness
  • Such a structure has a smaller retardation (difference in optical path length for the ordinary and extraordinary light beam, also expressed as d. ⁇ n, with d: thickness of the material, ⁇ n: optical anisotropy).
  • the broken symmetry can be obtained during manufacture by using polymer material obtained from a liquid crystal monomer.
  • a pretilt can be imposed.
  • the optically anisotropic layer then acquires a "splay deformation".
  • the ultimate director profile may also be influenced during manufacture by means of electric or magnetic fields, or both. This may result, for example in a preferred direction for the directors (cholesteric materials) or in a variation of the directors (discotic materials) in the anisotropic layer.
  • the optically anisotropic layer may alternatively consist of sub-layers; for example, the layer may comprise a uniaxial foil as a sub-layer.
  • the director profile may also extend locally across only a part of the thickness of the layer.
  • a further preferred embodiment of a display device according to the invention, with a cholesteric ordering in the anisotropic layer, is characterized in that the pitch of the cholesteric material is smaller than 0.25 micrometer. It is thereby achieved that, for example the part of the s-polarized light which is converted by the cholesteric effect of the anisotropic layer into p-polarized light is as small as possible so that the number of grey tints to be realised is considerably increased.
  • a (retardation) foil according to the invention, comprising an optically anisotropic layer of a material having a cholesteric ordering, is characterized in that, viewed transversely to the foil, the director profile in the optically anisotropic layer has a non- rotationally symmetrical pattern.
  • a preferred embodiment is characterized in that the director profile in at least a part of the optically anisotropic layer is provided at an angle to the boundary surfaces.
  • the boundary surfaces are understood to mean the macroscopic boundary surfaces transverse to the normal on the foil, in which possible disturbances in smoothness, provided deliberately or not deliberately, (such as, for example a sawtooth structure as mentioned above) are not taken into consideration.
  • Another foil comprising an optically anisotropic layer of a polymer material is characterized in that the optical axis of the optically anisotropic layer extends at an angle to a direction transverse to the substrates.
  • a further preferred embodiment of such a foil is characterized in that the optically anisotropic layer comprises a layer of polymerized discotic liquid crystal materials.
  • Fig. 1 is a diagrammatic cross-section of a part of a liquid crystal display device according to the invention
  • Fig. 2 shows a part of the device of Fig. 1,
  • Fig. 3 shows diagrammatically the optical behaviour of the device of Fig. 2, with indicatrices
  • Fig. 4 shows diagrammatically a number of variants of the device of Fig.
  • Fig. 5 shows the structure formula of a liquid crystal composition as used in an optically anisotropic layer with a cholesteric ordering
  • Fig. 6 shows the possible external influence of the director pattern in such an optically anisotropic layer during its manufacture
  • Fig. 7 shows a possible distribution in the director pattern after such an external influence
  • Fig. 8 shows diagrammatically how the angle dependence is reduced by means of the optically anisotropic layer at different voltages in the transmission/voltage characteristic.
  • Fig. 1 is a diagrammatic cross-section of a part of a liquid crystal display device comprising a liquid crystal cell 1 with a twisted nematic liquid crystal material 2 being present between two substrates 3, 4 of, for example glass, provided with electrodes 5, 6.
  • the device further comprises two polarizers 7, 8 whose direction of polarization is mutually crossed perpendicularly.
  • the device further comprises orientation layers (not shown) which orient the liquid crystal material on the inner walls of the substrates, in this example in the direction of the axes of polarization of the polarizers, such that the cell has a twist angle of 90 degrees.
  • the liquid crystal material has a positive optical anisotropy and a positive dielectric anisotropy.
  • the molecules, and hence the directors orient themselves to the field. In the ideal case, all molecules are thus substantially perpendicular to the two substrates (situation 11 in Fig. 2). However, in practice this situation requires a too high voltage; at customary voltages, the molecules extend at a smaller angle to the normal on the substrates 3, 4, corresponding to situation 12 in Fig. 2. From the direction 13 the viewing angle is rather in the direction of the molecules so that said angle dependence still occurs for light which is still transmitted at this voltage. This angle dependence may be explained by means of the "optical indicatrix", a three-dimensional geometric representation of the refractive index for each direction in which the vector of the electric field component of the light can oscillate.
  • the liquid crystal material in the driven state is uniaxial substantially throughout its thickness (in substantially all molecule layers, except for some molecule layers near the substrates, the molecules are perpendicular to the substrates)
  • the compensation layers as described in EP-A 0,372,973 may be manufactured in such a way that the associated indicatrix satisfies this.
  • Such a compensation layer comprises a cholesteric material with the molecular axis of the helix being transverse to the layer, so that the director pattern, viewed transversely to the layer, is rotationally symmetrical.
  • the indicatrix 14' has a principal axis which extends at a small angle to the axis transverse to the liquid crystal layer; it is, as it were, slightly tilted.
  • a compensation layer 9 between the liquid crystal material and the polarizer 8, with indicatrix 15 which is optimal for the situation 11 will have very little effect in this case.
  • the invention provides optically anisotropic compensation layers 9 having such an indicatrix 15' that the birefringence is substantially entirely compensated for the more practical adjustment of, for example situation 12; as it were, the indicatrix 15' is tilted in the same way with respect to the principal axis as the indicatrix 14'. Viewed in a direction perpendicular to the substrates, the director pattern in the optically anisotropic layer thus acquires a non-rotationally symmetrical pattern.
  • the director pattern in the optically anisotropic layer may be rotationally symmetrical itself, for example if a cholesteric foil having an optically anisotropic layer as described in EP-A 0.423.881 is used.
  • discotic (disc-shaped) liquid crystal materials may be used as basic materials for the anisotropic compensation layer 9. These discotic molecules may be provided with reactive groups so as to polymerize the materials. By means of polymerization, and dependent on, for example temperature or other peripheral conditions, the desired ordering may then be provided.
  • the interspace may be filled up with a material 10 having the same refractive index as the substrate material or as the foil material, for example UV-polymerized ethoxylated bisphenol-A diacrylate.
  • the manufacturing procedure may be based on sawtooth-shaped substrates, which results in a foil 9 as is shown in Fig. 4b.
  • the resultant optically anisotropic layer now has a sawtooth structure at both sides, the long sides of the sawtooth extending at a small angle to the substrates 3, 4.
  • the directors of the molecules of the cholesteric liquid crystal material from which the foil 9 is made direct themselves parallel to these long sides, which is shown by means of the shaded structure in the optically anisotropic layer (foil) 9 in Figs. 1 and 4.
  • the optical axis of the foil 9 now no longer coincides with the optical axis of the liquid crystal cell formed by the liquid crystal material 2 and the substrates 3 (because the director profile in at least a part of the optically anisotropic layer is provided at an angle to the boundary surfaces, the boundary surface being considered as a surface bounding the foil transverse to the foil, while surface disturbances such as the teeth of the sawtooth in this example are ignored.
  • the director profile in the foil thus has a broken symmetry, viewed transversely to the substrate 3, 4.
  • the pitch of the sawtooth is chosen to be smaller than the dimension of a pixel of the display device.
  • the sawtooth patterns at both sides of the foil may be rotated with respect to each other, for example through 90 degrees. The total structure then has a smaller retardation.
  • the sawtooth structure may alternatively be provided on one boundary surface only, so that a splay deformation is introduced in the foil 9 (Fig. 4c).
  • the directors then have an angle to a plane parallel to the substrates over a part of the thickness of the foil, so that a broken axial symmetry is obtained again.
  • the same can be achieved by making use of flat substrates during manufacture and by inducing a pretilt on one or both surfaces when the liquid cholesteric material is being provided; upon subsequent freezing (netting) of the structure, this structure is maintained so that again a number of directors has an angle to a plane parallel to the substrates and a broken axial symmetry is obtained.
  • the anisotropic layers based on discotic liquid crystal materials may also be given such a structure.
  • the directors of the discotic molecules now extend at an angle to the normal and, viewed transversely to the substrates 3, 4, the foil again has a broken symmetry.
  • the sawtooth structure may again be provided on one boundary surface only so that a bend deformation is introduced in the foil 9.
  • the directors are not directed transversely to the substrates over a part of the thickness of the foil, so that a broken axial symmetry is obtained again.
  • a substrate is preferably used which induces a pretilt in the same way as described hereinbefore. If tilting is induced by means of a magnetic field, it can be oriented obliquely to the surfaces 16, as is denoted by arrow 19 in Fig. 6b.
  • the director is situated along a helix transverse to the compensation layer which has a small pitch with respect to the thickness of the compensation layer.
  • Such a compensator has axial symmetry, i.e. all directions of the director occur to a substantially equal extent; there is no preference for a given azimuth angle ⁇ . This is shown by means of a broken line in Fig. 7.
  • This axial symmetry can be broken by exposing the cholesteric layer during polymerization to a magnetic field transverse to the layer, so that a preference for given azimuth angles is introduced, which is shown by means of the line 21 in Fig. 7.
  • the extent of asymmetry may be increased by adding a uniaxial foil having a small ⁇ n to the foil 9; this may be, for example the substrate on which the monomer layer is provided (for example (stretched) cellulose triacetate or (stretched) polycarbonate).
  • the layer may be slightly stretched after the polymerization has been partly finished, while the birefringence of the stretched substrate on which the monomer layer is provided may also contribute to the breaking of the symmetry.
  • the last-mentioned measures may also be used for disturbing the axial symmetry in the foil in layers based on discotic materials.
  • the extent of "refraction" of the symmetry is also determined by the voltage range in which birefringence must be compensated so as to obtain complete extinction.
  • a range 22 in the transmission/voltage curve may be chosen around a given voltage V ⁇ p (Fig. 8a) in which the position of the directors in the liquid crystal material hardly deviates from that shown in the situation 11 of Fig. 2. In this case, a slightly broken symmetry is sufficient.
  • a range 22 * in the transmission/voltage curve is chosen around a given voltage V' ⁇ (Fig. 8b) in which the position of the directors in the liquid crystal material deviates considerably from that in the situation 11 of Fig. 2, a much stronger broken symmetry must be used.
  • the anisotropic layer 9 may be provided with areas having a more or less broken symmetry. In the first areas the viewing angle dependence is then slightly overcompensated, while it is compensated slightly too little in the other areas. The dimension of the areas is smaller than that of a pixel. In this way, a symmetrical viewing angle dependence is obtained.
  • the invention is of course not limited to the examples shown.
  • a plurality of foils (anisotropic layers) 9 may be arranged one behind the other and, for example each of them may compensate optimally for a different given voltage V comp .
  • two foils may be provided on different sides of the liquid crystal layer.
  • the invention provides a liquid crystal display cell with one or more compensation layer(s) and, viewed transversely to the cell, a broken (non- rotationally symmetrical) refractive index pattern or indicatrix.
  • the associated birefringence of the compensation layer is complementary to that associated with a given voltage across the liquid crystal cell.
  • the compensation layer may be manufactured in many different ways by making use of cholesteric or discotic foils for this layer.

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Liquid Crystal (AREA)
  • Polarising Elements (AREA)

Abstract

Cellule d'affichage à cristaux liquides possédant une couche de compensation qui présente en coupe une indicatrice ou un schéma d'indice de réfraction à symétrie brisée (non rotatoire). Afin d'obtenir une dépendance à petit angle, la biréfringence associée à la couche de compensation est complémentaire de celle associée à une tension donnée traversant la cellule à cristaux liquides, de manière qu'à l'état activé, l'axe optique de la couche de compensation coïncide sensiblement avec l'orientation des directeurs. On peut fabriquer la couche de compensation de différentes façons en utilisant des feuilles cholestériques ou des feuilles à base de cristaux liquides discoïdes.
PCT/IB1995/000644 1994-08-23 1995-08-14 Dispositif d'affichage a cristaux liquides et feuille retardatrice WO1996006380A2 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP95926478A EP0725943B1 (fr) 1994-08-23 1995-08-14 Dispositif d'affichage a cristaux liquides et feuille retardatrice
JP50790596A JP3358815B2 (ja) 1994-08-23 1995-08-14 液晶表示装置及びリタデーションフォイル
DE69530751T DE69530751T2 (de) 1994-08-23 1995-08-14 Fluessigkristall-anzeigevorrichtung und verzoegerungsfolie

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP94202402.7 1994-08-23
EP94202402 1994-08-23
EP95200119 1995-01-18
EP95200119.6 1995-01-18

Publications (2)

Publication Number Publication Date
WO1996006380A2 true WO1996006380A2 (fr) 1996-02-29
WO1996006380A3 WO1996006380A3 (fr) 1996-05-02

Family

ID=26136507

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB1995/000644 WO1996006380A2 (fr) 1994-08-23 1995-08-14 Dispositif d'affichage a cristaux liquides et feuille retardatrice

Country Status (5)

Country Link
JP (1) JP3358815B2 (fr)
KR (1) KR100415334B1 (fr)
MY (1) MY118868A (fr)
TW (1) TW404513U (fr)
WO (1) WO1996006380A2 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000031579A1 (fr) * 1998-11-20 2000-06-02 Koninklijke Philips Electronics N.V. Systeme de projection d'image a contraste ameliore
WO2001020393A1 (fr) * 1999-09-16 2001-03-22 Merck Patent Gmbh Compensateur optique et dispositif d'affichage a cristaux liquides ii
WO2001020394A1 (fr) * 1999-09-16 2001-03-22 Merck Patent Gmbh Compensateur optique et dispositif d'affichage a cristaux liquides i
US6897915B1 (en) * 2000-09-27 2005-05-24 Kent State University Non-lithographic photo-induced patterning of polymers from liquid crystal solvents with spatially modulated director fields
US6985291B2 (en) 2001-10-01 2006-01-10 3M Innovative Properties Company Non-inverting transflective assembly
DE102004031440B4 (de) * 2003-12-30 2011-03-31 Lg Display Co., Ltd. Kompensationsfilm, Herstellverfahren für einen solchen sowie LCD unter Verwendung eines solchen

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20000065950A (ko) * 1999-04-12 2000-11-15 권문구 보상필름을 이용한 액정표시장치
JP5657288B2 (ja) * 2010-07-01 2015-01-21 スタンレー電気株式会社 液晶表示素子
JP5657287B2 (ja) * 2010-07-01 2015-01-21 スタンレー電気株式会社 液晶表示素子

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0352724A1 (fr) * 1988-07-27 1990-01-31 Kabushiki Kaisha Toshiba Dispositif d'affichage à cristal liquide
US5241408A (en) * 1991-02-07 1993-08-31 Kabushiki Kaisha Toshiba Liquid crystal display device with compensation and lc twist angle varying in a nonlinear fashion in the thickness direction
EP0576342A1 (fr) * 1992-06-26 1993-12-29 THOMSON multimedia Dispositif d'affichage à cristal liquide nématique en hélice
EP0576931A2 (fr) * 1992-06-18 1994-01-05 Casio Computer Company Limited Dispositif d'affichage à cristal liquide
GB2272779A (en) * 1992-11-18 1994-05-25 Fuji Photo Film Co Ltd Optically anisotropic element

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0352724A1 (fr) * 1988-07-27 1990-01-31 Kabushiki Kaisha Toshiba Dispositif d'affichage à cristal liquide
US5241408A (en) * 1991-02-07 1993-08-31 Kabushiki Kaisha Toshiba Liquid crystal display device with compensation and lc twist angle varying in a nonlinear fashion in the thickness direction
EP0576931A2 (fr) * 1992-06-18 1994-01-05 Casio Computer Company Limited Dispositif d'affichage à cristal liquide
EP0576342A1 (fr) * 1992-06-26 1993-12-29 THOMSON multimedia Dispositif d'affichage à cristal liquide nématique en hélice
GB2272779A (en) * 1992-11-18 1994-05-25 Fuji Photo Film Co Ltd Optically anisotropic element

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000031579A1 (fr) * 1998-11-20 2000-06-02 Koninklijke Philips Electronics N.V. Systeme de projection d'image a contraste ameliore
WO2001020393A1 (fr) * 1999-09-16 2001-03-22 Merck Patent Gmbh Compensateur optique et dispositif d'affichage a cristaux liquides ii
WO2001020394A1 (fr) * 1999-09-16 2001-03-22 Merck Patent Gmbh Compensateur optique et dispositif d'affichage a cristaux liquides i
US6903789B1 (en) 1999-09-16 2005-06-07 Merck Patent Gmbh Optical compensator and liquid crystal display II
US6912030B1 (en) 1999-09-16 2005-06-28 Merck Patent Gmbh Optical compensator and liquid crystal display I
US6897915B1 (en) * 2000-09-27 2005-05-24 Kent State University Non-lithographic photo-induced patterning of polymers from liquid crystal solvents with spatially modulated director fields
US7372480B1 (en) 2000-09-27 2008-05-13 Kent State University Non-lithographic photo-induced patterning of polymers from liquid crystal solvents with spatially modulated director fields
US6985291B2 (en) 2001-10-01 2006-01-10 3M Innovative Properties Company Non-inverting transflective assembly
US7084938B2 (en) 2001-10-01 2006-08-01 3M Innovative Properties Company Non-inverting transflective assembly
US7245431B2 (en) 2001-10-01 2007-07-17 3M Innovative Properties Company Reflective polarizer assembly
DE102004031440B4 (de) * 2003-12-30 2011-03-31 Lg Display Co., Ltd. Kompensationsfilm, Herstellverfahren für einen solchen sowie LCD unter Verwendung eines solchen
US8599339B2 (en) 2003-12-30 2013-12-03 Lg Display Co., Ltd. Compensation film, manufacturing method thereof and liquid crystal display using the same

Also Published As

Publication number Publication date
MY118868A (en) 2005-02-28
KR100415334B1 (ko) 2004-08-30
WO1996006380A3 (fr) 1996-05-02
JPH09504626A (ja) 1997-05-06
JP3358815B2 (ja) 2002-12-24
KR960706102A (ko) 1996-11-08
TW404513U (en) 2000-09-01

Similar Documents

Publication Publication Date Title
EP0840904B1 (fr) Compensateur
US20060139535A1 (en) Method of manufacturing a liquid-crystal display device
KR101029933B1 (ko) 광학 등방성 상을 갖는 광학적으로 보정된 전기-광학 광변조 소자
JP2006146256A (ja) Ｏプレート補償器、その製造方法およびネマッチック液晶ディスプレイ
EP0757805B1 (fr) Dispositif d'affichage a cristaux liquides et film retard
KR100744818B1 (ko) 위상차 광학소자와 그 제조방법 및 액정표시장치
EP1131671A1 (fr) Ecran a cristaux liquides alignes verticalement et deformes en helice
WO1996006380A2 (fr) Dispositif d'affichage a cristaux liquides et feuille retardatrice
US7477343B2 (en) Negative retardation film
EP0865630A1 (fr) Dispositif d'affichage a cristaux liquides et composant optique comportant un polariseur
US7202926B2 (en) Cholesteric reflective retardation optical element with directors at top surface of optical element parallel to those at the bottom surface of the optical element
KR100483528B1 (ko) 보상필름및이를이용한광시야각액정표시장치
KR100431052B1 (ko) 표면 굴곡에 의하여 형성된 다중 영역 효과를 가지는 액정표시 장치
EP0725943B1 (fr) Dispositif d'affichage a cristaux liquides et feuille retardatrice
KR20040025862A (ko) Ａ 플레이트 또는 ｏ 플레이트 위상차 필름을 포함하는 신모드 액정 디스플레이
JPH06235914A (ja) 液晶表示装置
JPH0416916A (ja) 液晶表示素子
KR19990074568A (ko) 위상차 보상막을 이용한 광시야각 액정 표시 장치

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): JP KR SG

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

WWE Wipo information: entry into national phase

Ref document number: 1995926478

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 1019960702116

Country of ref document: KR

AK Designated states

Kind code of ref document: A3

Designated state(s): JP KR SG

AL Designated countries for regional patents

Kind code of ref document: A3

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
WWP Wipo information: published in national office

Ref document number: 1995926478

Country of ref document: EP

WWG Wipo information: grant in national office

Ref document number: 1995926478

Country of ref document: EP