WO2001007962A1 - Flüssigkristallschaltelement und flüssigkristalldarstellungseinrichtung - Google Patents
Flüssigkristallschaltelement und flüssigkristalldarstellungseinrichtung Download PDFInfo
- Publication number
- WO2001007962A1 WO2001007962A1 PCT/EP2000/006879 EP0006879W WO0107962A1 WO 2001007962 A1 WO2001007962 A1 WO 2001007962A1 EP 0006879 W EP0006879 W EP 0006879W WO 0107962 A1 WO0107962 A1 WO 0107962A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- liquid crystal
- switching element
- ccp
- layer
- cch
- Prior art date
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
- G02F1/13363—Birefringent elements, e.g. for optical compensation
-
- 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
- G02F1/137—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 characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
- G02F1/139—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 characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent
- G02F1/1393—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 characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering based on orientation effects in which the liquid crystal remains transparent the birefringence of the liquid crystal being electrically controlled, e.g. ECB-, DAP-, HAN-, PI-LC cells
-
- 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
- G02F1/133638—Waveplates, i.e. plates with a retardation value of lambda/n
-
- 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
- G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
- G02F1/133738—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers for homogeneous alignment
Definitions
- Liquid crystal switching element and liquid crystal display device Liquid crystal switching element and liquid crystal display device
- the invention relates to an electro-optical liquid crystal switching element comprising at least one polarizer and a liquid crystal layer which has an initial orientation in which the liquid crystal molecules are oriented essentially parallel to the substrates and essentially parallel to one another, in which the reorientation of the liquid crystals from their essentially to the Output parallel orientation substrates is caused by a corresponding electrical field, which is oriented essentially parallel to the substrates in the case of liquid crystal materials with negative dielectric anisotropy and substantially perpendicular to the substrates in the case of liquid crystal materials with positive dielectric anisotropy, the liquid crystal layer an extremely low optical delay d- ⁇ n in the range of
- the liquid crystal switching element preferably contains, in addition to the liquid crystal layer, a further birefringent layer, preferably a ⁇ / 4 layer or two ⁇ / 4 layers or a ⁇ / 2 layer, and liquid crystal display systems containing such liquid crystal switching elements.
- the present invention furthermore relates to liquid-crystal media, in particular having a small birefringence, for use in the liquid-crystal display systems.
- liquid crystal display systems containing the liquid crystal switching elements include screens of televisions, computers, e.g. "Notebook” computers or “desktop” computers, control centers and other devices, e.g. Gambling devices, electro-optical displays, such as displays of clocks, pocket calculators, electronic (pocket) games, portable data storage devices, such as PDAs (personal digital assistants) or mobile phones.
- liquid crystal display systems according to the invention are well suited for applications with display of gray levels, such as. B. TVs, computer monitors and multimedia devices.
- gray levels such as. B. TVs, computer monitors and multimedia devices.
- network-independent operation as well as operation on the voltage network is possible. Network operation is often preferred.
- the liquid crystal switching elements typically used in such liquid crystal display devices are the known TN (twisted nematic) switching elements, e.g. B. according to Schadt, M. and Helfrich, W. Appl. Phys. Lett. 18, pp. 127 ff (1974) and in particular in their special form with a small optical delay d- ⁇ n in the range from 150 nm to 600 nm according to DE 30 22 818, STN (super twisted nematic). B. according to GB 2 123 163, Waters, CM, Brimmel, V, and Raynes, E. Pproc. 3 rd Int. Display Research Conference, Kobe 1983, pp. 396 ff and Proc. SID 25/4, pp.
- TN twisted nematic switching elements
- ERZATZZ3L ATT (RULE 26) video should be used, such as in multimedia applications on computer screens or on TVs.
- short switching times preferably less than 32 ms, particularly preferably less than 16 ms, are desirable.
- the requirements regarding the viewing angle dependency of the contrast strongly depend on the use of the display devices.
- the horizontal viewing angle range is most important for television screens and computer monitors, whereas centrosymmetrical or at least almost centrosymmetrical viewing angle distributions are desired in other applications.
- Displays with almost centrosymmetrical viewing angle distributions are required in particular for projection displays in order to utilize the optical apertures as well as possible, but also for computer screens with a so-called "swiss-base". These screens allow the display to be tilted by 90 ° in order to maintain the resolution of the display from Switch portrait format ("portrait mode") to wide format (“landscape mode"). Obviously, such displays must have similar horizontal and vertical viewing angles, since these are interchanged when tilted.
- VANs are often characterized by inadequate color saturation and color depth. Furthermore, the production of VANs is complex because of the difficult to achieve homeotropic orientation and because of the long filling times.
- EP 0 264 667 describes TN cells with twist angles ( ⁇ , also called twist angle or twist for short) in the range from 10 ° to 80 ° with d- ⁇ n in the range from 0.2 ⁇ m to 0.7 ⁇ m. Compared to TN cells with 90 ° twist, these have an improved viewing angle dependency of the contrast as well as a lower steepness of the electro-optic
- DE 40 10 503 and corresponding WO 92/17 831 describe, among other things, TN switching elements with twist angles in the range from more than 0 ° to 90 °, which contain one or more compensation layers, the compensation layers for compensating the optical path difference of the switching Cell have the same optical delay as the switching cell. For cells with a twist angle called small, e.g. at 22.5 °, the compensation layer can also be omitted.
- the switching elements described in this publication in particular have an insufficient contrast, which is often accompanied by a still considerable dependence on the viewing angle of the contrast. Furthermore, the switching times, especially those for the control of gray levels, are usually insufficient.
- ERZAT ⁇ BLATT (RULE 26) with 90 ° twist and ad- ⁇ n in the range from 0.15 ⁇ m to 0.70 ⁇ m
- the use of a cholesteric liquid crystal material with a small cholesteric pitch (P) with ad / P ratio in the range from 0.1 to 0.5 proposed.
- the TN switching elements of DE 42 12 744 have disadvantages similar to those of the switching elements described in EP 0 264 667.
- WO 91/06889 and the corresponding U.S.P. 5,319,478 describe the minimal optical delays of ⁇ / 2 and ⁇ / 4 and suggest their operation with circularly polarized light. Cells with a twisted structure of the liquid crystal are preferred.
- the characteristic directions of the optical components form angles to one another which are different from 0 ° and 90 °.
- the switching elements with birefringent layers described here have a complicated structure and are therefore not easy to manufacture.
- the brightness is not particularly good, particularly in the case of the switching elements with a plurality of birefringent layers.
- the liquid crystal switching elements according to the present invention contain a liquid crystal layer with a small optical delay and optionally a further birefringent layer, preferably a ⁇ / 4 layer, a ⁇ / 2 layer or two ⁇ / 4 layers, and at least one polarizer.
- the two ⁇ / 4 layers can replace the ⁇ / 2 layer.
- the transmissive or transflective liquid crystal switching elements according to the present invention preferably contain a polarizer and an analyzer, which are arranged on opposite sides of the arrangement of liquid crystal layer and birefringent layer.
- the polarizer and analyzer are referred to together as
- FIG. 1 schematically shows the basic structure of a liquid switching element according to the invention in the preferred embodiment of a transmissive switching element with a light source, with a
- Liquid crystal layer with two polarizers, with a birefringent layer (here, as preferred, a ⁇ / 4 layer) and with crossed polarizers.
- Figure 1a is a side view.
- the substrates of the liquid crystal cell between which the liquid crystal layer is located, the orientation layers on the inside of the substrate and the electrode layers on one or both substrates have been omitted.
- One of the two polarizers is located on one of the two sides of the liquid crystal cell.
- the birefringent layer is
- REPLACEMENT SHEET (RULE 26 det between the liquid crystal cell and one of the two polarizers, preferably, as shown on the side facing away from the light source, that is between the liquid crystal cell and the analyzer.
- the fast axis of the birefringent layer is parallel to the transmission sleeve of the polarizer.
- the light from the light source (backlight BL for short) thus passes through the polarizer, the liquid crystal cell, the birefringent layer and the analyzer one after the other before it comes to the viewer (not shown).
- the fast axis of the birefringent layer is preferably at an angle of 45 ° to the polarizer and the projection of the orientation of the liquid crystal in the middle of the cell between the substrates is preferably parallel to the direction of transmission of the polarizer.
- Figure 1b is a top view, i.e. along the z-axis in Figure 1a. It shows the orientation of the relevant axes of the individual optical components to each other and defines the corresponding angles.
- ⁇ P P denotes the angle between the transmission axes of the two polarizers (here 90 °)
- ⁇ PL the angle between the transmission axis of the polarizer and the preferred direction of the liquid crystal director in the middle of the layer between the substrates (n
- the fast axis of the ⁇ / 4 layer is parallel to the transmission axis of the polarizer.
- the angle ⁇ PD is 0 °.
- the viewing angle in the plane of the switching element ( ⁇ ) is given with examples of 0 °, 90 °, 180 ° and 270 °.
- the viewing angles in the plane of the display ( ⁇ or ⁇ ') and perpendicular to the perpendicular ( ⁇ ) are defined in Figure 2.
- the viewing angles ⁇ 'begin with ⁇ ' 0 ° in the quadrant with the highest contrast at the angle of the highest contrast, which is generally in the direction of n 1 1.
- ⁇ ' is shifted by 45 ° with respect to ⁇ .
- REPLACEMENT SHEET (RULE 26)
- the fast axis of the ⁇ / 4 layer is parallel to the direction of transmission of the polarizer, if two or more polarizers are present, to that of the polarizer adjacent to the ⁇ / 4 layer (see Figure 1 b). The same applies to the presence of two ⁇ / 4 layers or a ⁇ / 2 layer.
- Linear polarizers are preferably used in the switching elements according to the present application. These linear polarizers can be single-layer polarizers or consist of a combination of several layers, wherein these layers can also comprise two or more polarizing layers.
- the degree of polarization of the polarizers is chosen to be sufficiently high to achieve good contrast, but also low enough to obtain good brightness of the switching element.
- the use of a polarizer with a relatively low degree of polarization, a so-called "clean up" polarizer often proves to be effective
- the polarizers are preferably connected with an adhesive of a corresponding refractive index in order to avoid light losses on the surfaces.
- the liquid crystal layer is usually held between two substrates. At least one of the substrates is translucent, preferably both substrates are translucent.
- the translucent substrates consist, for. B. from glass, quartz glass, quartz or from transparent plastics, preferably from glass and particularly preferably from borosilicate glass.
- the substrates form a cell in which the liquid crystal material of the liquid crystal layer is held.
- the substrates are preferably planar.
- spacers The spacing of the flat substrates is kept essentially constant over the entire surface by means of spacers. These spacers can only be used in the adhesive frame or, alternatively, can be distributed over the entire surface of the cell. The use of spacers only in the adhesive frame is reduced
- the preferred substrate thicknesses are 0.3 mm to 1.1 mm, particularly preferably 0.4 mm to 0.7 mm. For the larger diagonals of the cells, the substrates with the larger thicknesses are preferred.
- the liquid crystal switching elements according to the invention are distinguished by very good gray-scale capacity, a low dependency of the contrast on the viewing angle, even in color display, with a large viewing angle range and low contrast inversion, and in particular by very short switching times.
- the inverse contrast such as. B. defined in DE 42 12 744, which e.g. occurs in advertisements according to DE 30 22 818, especially at larger viewing angles ⁇ , significantly reduced.
- spacers in spherical or cylindrical form both from plastics and from inorganic materials, such as. B. glass fiber sections exist.
- regular, raised structures on preferably one of the substrates can be used as spacers. These regular, raised structures can take various forms, such as: B. rectangular, square, oval or round columns or pyramid shafts, but also strip or wavy structures.
- the liquid crystal switching elements In the case of reflective switching elements, the liquid crystal switching elements according to the present application have at least one polarizer and one reflector, at least one polarizer and the reflector being located on the opposite sides (ie substrates) of the liquid crystal cell. In the case of transmissive or reflective switching elements, these have at least two polarizers, at least one of which is arranged on each of the two opposite sides of the liquid crystal cell (so-called sandwich structure).
- the compulsory polarizers mentioned are preferably linear polarizers and in particular linear polarizers with a high degree of polarization.
- the switching elements according to the invention can be made of iron or can contain several other polarizers. These can be so-called “clean up" polarizers with a lower degree of polarization but high transmission. However, in particular with reflective switching elements, a further polarizer with a high degree of polarization can also be present. This is preferably arranged between the liquid crystal cell and the reflector.
- additional polarizers it is generally less preferred, since in most cases it leads to a reduction in transmission, but is particularly common in connection with so-called brightness-increasing components, which may contain cholesteric polymer films, for example.
- the two obligatory polarizers are either crossed or arranged parallel to one another.
- the directions of the arrangement of the polarizers are related to their absorption axes.
- the crossed arrangement of the polarizers is preferred.
- the angle of the absorption axes to each other is in the case of crossed polarizers in the range from 75 ° to 105 °, preferably from 85 ° to 95 °, particularly preferably from 88 ° to 92 °, particularly preferably from 89 ° to 91 ° and very particularly preferred 90 ° and in the case of parallel polarizers from -15 ° to 15 °, preferably from -5 ° to 5 °, particularly preferably from
- REPLACEMENT SHEET (RULE 26) -2 ° to 2 °, particularly preferably from -1 ° to 1 ° and very particularly preferably 0 °.
- the angle between the absorption axis of the polarizer adjacent to the liquid crystal layer with the direction of the orientation of the director of the liquid crystal material in the unswitched (field-free) state on the adjacent substrate ( ⁇ PL ) is 35 ° to 55 °, preferably 40 ° to 50 °, particularly preferably 43 ° up to 47 °, in particular 44 ° to 46 ° and ideally 45 °.
- ⁇ P the reference direction for the indication of the angle ⁇ P is the projection of the orientation of the liquid crystal director in the middle between the two substrates of the cell onto the substrate adjacent to the polarizer.
- Substrates particularly in the case of switching elements with a birefringent layer, in particular with a ⁇ / 4 or ⁇ / 2 layer, or with a plurality of birefringent layers, in particular with two ⁇ / 4 layers, preferably from -20 ° to 20 ° preferably from -10 ° to 10 °, particularly preferably from -5 ° to 5 °, very particularly preferably from
- the liquid crystal layer is essentially untwisted and particularly preferably untwisted.
- a twist angle ( ⁇ ) of -6 ° to 6 ° is preferred.
- the twist angle is particularly preferably from -1.0 ° to 1.0 °, very particularly preferably -0.5 to 0.5, particularly preferably 0.0 °.
- REPLACEMENT SHEET takes place according to usual procedures.
- the oblique evaporation with inorganic compounds preferably oxides such as SiO x
- the orientation on antiparallel rubbed surfaces in particular on antiparallel rubbed polymer layers such as polyimide layers, or orientation on photopolymerized anisotropic polymers
- vertical orientation English: “vertical algnment”, VA for short
- lecithin or surface-active substances can also be used for homeotropic orientation.
- the liquid crystal switching elements according to the present invention can be manufactured with the production methods in the production facilities of the most widely used liquid crystal switching elements, the TN liquid crystal switching elements.
- the orientation of the liquid crystal director such as. B. with STN (high tilt angle) or with VAN (homeotropic orientation) necessary.
- IPS with a twisted initial state and in particular to STN additives such as chiral dopants can be largely and often even completely dispensed with. This eliminates another process parameter, which is sometimes difficult to control.
- the surface angle of attack on the substrates ( ⁇ 0 , also English: Tilt angle or Tilt for short) is in the range from 0 ° to 15 °, preferably in the range from 0 ° to 10 °, particularly preferably in the range from 0.1 ° to 5 ° and particularly preferably in the range from 0.2 ° to 5 ° and most preferably in the range from 0.3 ° to 3 °.
- the surface angle of attack on the orientation layer on at least one of the substrate surfaces is from 0.5 ° to 3 °.
- the angle of attack on both substrates is preferably essentially identical.
- the electrodes on the substrates are translucent, at least on one of the substrates and preferably on both substrates.
- Indium tin oxide (ITO) is preferably used as the material for the electrodes, but aluminum, copper, silver and / or gold can also be used.
- REPLACEMENT SHEET (RULE 26) Since the surface angle of attack can be small in the liquid crystal display elements according to the invention, the use of anisotropically photopolymerizable materials, such as. B. cinnamic acid derivatives, the so-called "photo orientation" particularly advantageous to use.
- the individual liquid crystal switching elements or their individual display electrodes are divided into sub-areas with different orientations of the liquid crystal director, at least in the switched state, but generally also in the unswitched state, so-called domains.
- These domains with different orientation in the switched state can e.g. B. induced by different surface angles or by different preferred orientations on the substrates.
- they can also be induced by corresponding, sufficiently obliquely oriented, electrical fields, for example by slotted electrodes, or by non-planar surface topographies.
- the smallest possible angle of attack preferably of 0 °
- the individual picture elements of the multidomain switching elements preferably contain two or more, preferably even multiples of two, very particularly preferably two or four domains.
- the angles of attack (tilt) of the liquid crystal director in the middle of the liquid crystal layer ( ⁇ M , English: midplane tilt angle) of these domains in the switched state are preferably opposed to one another in pairs.
- the viewing angle dependencies of the domains also referred to as sub-pixels
- the light scattering disclinations occurring at the domain boundaries are covered by an appropriate mask, preferably a black mask, in order to improve the contrast.
- the larger of the preferred surface angles of attack are particularly advantageous for the definition of the preferred quadrant, that is to say the quadrant in which the best contrast is observed.
- they lead to the suppression of areas with a reverse angle of attack (“reverse tilt domains”), which occur particularly easily when non-orthogonal fields are created.
- active electrical switching elements of the active matrix come both bipolar structures such as diodes, e.g. B. MIM diodes or back to back diodes, optionally with "reset", as well as three-pole structures such as transistors, for. B. thin film transistors (TFTs of "thin film transistors") or varistors for use. TFTs are preferred for the liquid crystal display devices according to the present application.
- the active semiconductor medium of these TFTs is amorphous silicon (a-Si), polycrystalline silicon (poly-Si) or cadmium selenide (CdSe), preferably a-Si or poly-Si.
- a-Si amorphous silicon
- poly-Si polycrystalline silicon
- CdSe cadmium selenide
- poly-Si refers equally to high-temperature and low-temperature poly-Si.
- the liquid crystal layer preferably has an optical delay (d- ⁇ n) from 0.14 ⁇ m to 0.42 ⁇ m, particularly preferably from 0.22 ⁇ m to 0.34 ⁇ m, particularly preferably from 0, 25 ⁇ m to 0.31 ⁇ m, very particularly preferably from 0.27 ⁇ m to 0.29 ⁇ m and ideally from 0.28 ⁇ m.
- d- ⁇ n optical delay
- Liquid crystal materials with small birefringence ⁇ n are preferably used for this purpose.
- the birefringence of the liquid crystal materials is preferably 0.02 to 0.09, particularly preferably 0.04 to 0.08, particularly preferably 0.05 to 0.075, very particularly preferably 0.055 to 0.070 and ideally approximately 0.060 to 0.065.
- the layer thickness of the liquid crystal layer is preferably 1 ⁇ m to
- liquid crystal display devices with liquid crystal cells with a diagonal of up to 6 layer thicknesses of the liquid crystal layer from 1 ⁇ m to 4 ⁇ m and particularly from 2 ⁇ m to 3 ⁇ m are preferred.
- layer thicknesses of the liquid crystal layer are 3 ⁇ m up to 6 ⁇ m and particularly from 4 ⁇ m to 5 ⁇ m are preferred.
- the liquid crystal layer has an optical delay (d- ⁇ n) from 0.20 ⁇ m to 0.37 ⁇ m, preferably from 0.25 ⁇ m to 0.32 ⁇ m, particularly preferably from 0.26 ⁇ m to 0.30 microns, most preferably from 0.27 microns to 0.29 microns, and most preferably from 0.28 microns.
- d- ⁇ n optical delay
- the display element surprisingly does not require a ⁇ / 4 layer in some applications. Nevertheless, with the appropriate polarizer position, preferably at an angle of essentially 45 ° to the preferred liquid crystal direction, it is characterized by good brightness, excellent contrast and excellent viewing angle dependence and very good grayscale and color level display. Without a ⁇ / 4 layer, a very wide viewing angle area is achieved for the viewing angle ⁇ , but not for all viewing angles ⁇ . In contrast, the viewing angle area for the switching elements with ⁇ / 4 layer is significantly more centrosymmetric, i.e. for all viewing angles ⁇ it extends to similar, large values of the viewing angle ⁇ (see also Figures 9a) and 9b) for examples 1 and 2) ,
- the display elements preferably contain a ⁇ / 4 layer and the liquid crystal layer has an optical delay [(d- ⁇ n) LC ] of
- REPLACEMENT SHEET (RULE 26) 0.10 ⁇ m to 0.45 ⁇ m, preferably from 0.20 ⁇ m to 0.37 ⁇ m, particularly preferably from 0.25 ⁇ m to 0.32 ⁇ m, very particularly preferably from 0.26 ⁇ m to 0.30 ⁇ m, in particular particularly preferably from 0.27 ⁇ m to 0.29 ⁇ m, and most preferably from 0.28 ⁇ m.
- the liquid crystal layer thus behaves in the unswitched state approximately like a ⁇ / 2-
- (d- ⁇ n) c differs from 0.28 ⁇ m, specifically in the range from 0.10 ⁇ m to 0.27 ⁇ m or 0.30 ⁇ m to 0.45 ⁇ m, particularly preferably from 0.14 ⁇ m to 0.25 ⁇ m or 0.32 ⁇ m to 0.42 ⁇ m, very particularly preferably from 0.22 ⁇ m to 0.25 ⁇ m, or from 0.32 ⁇ m to 0.34 ⁇ m.
- the wavelength ⁇ always relates preferably to the wavelength of the maximum sensitivity of the human eye, to 554 nm, unless explicitly stated otherwise.
- ⁇ / 4 layer and ⁇ / 4 plate, or ⁇ / 2 layer and ⁇ / 2 plate are generally used synonymously in the present application.
- the term ⁇ in ⁇ / 4 layer and ⁇ / 2 layer means a wavelength in the range of ⁇ ⁇ 30%, preferably ⁇ ⁇ 20%, particularly preferably ⁇ ⁇ 10%, particularly preferably ⁇ ⁇ 5% and entirely particularly preferably ⁇ ⁇ 2%. Unless otherwise stated, the wavelength here is 554 nm.
- the wavelength of the ⁇ / 4 layer or ⁇ / 2 layer is specified in general and in particular in the case of a noticeable spectral distribution as its central wavelength.
- the ⁇ / 4 layer or ⁇ / 2 layer is an inorganic layer or preferably an organic layer, e.g. B. from a birefringent polymer, e.g. B. stretched films (PET) or liquid crystalline polymers.
- a birefringent polymer e.g. B. stretched films (PET) or liquid crystalline polymers.
- Liquid crystal layer is preferred in view of the advantageous short switching times that can be achieved thereby. In addition, it rather allows the use of conventional liquid crystal materials or at least places less demands on the often difficult realization of the small ⁇ n values.
- liquid crystal materials with a relatively high clearing point are particularly preferred since the effect of the ⁇ / 4 layer is clearly temperature-dependent owing to the temperature dependence of the birefringence of the liquid crystal materials [ ⁇ n L c (T)] and ⁇ n LC (T) for liquid crystal materials with a high clearing point is relatively low.
- the temperature dependency of the entire optical arrangement is thus kept relatively small and, if necessary, can also be compensated for more easily.
- the liquid crystal layer has an optical delay of 0.07 ⁇ m to 0.21 ⁇ m, preferably 0.11 ⁇ m to 0.17 ⁇ m, particularly preferably 0.12 ⁇ m to 0.16 ⁇ m, particularly preferably from 0.13 ⁇ m to
- the display element preferably has at least one birefringent layer, preferably one ⁇ / 2 layer or two ⁇ / 4 layers, in addition to the liquid crystal layer.
- liquid crystal materials with small birefringence ⁇ n are also preferably used.
- the birefringence of the liquid crystal materials is preferably 0.02 to 0.09, particularly preferably 0.04 to 0.08, particularly preferably 0.05 to 0.07, very particularly preferably 0.055 to 0.065 and ideally approximately 0.060.
- the layer thickness of the liquid crystal layer is preferably 0.5 ⁇ m to 7 ⁇ m, preferably 1 ⁇ m to 5 ⁇ m, particularly preferably 1.5 ⁇ m to 4 ⁇ m and particularly preferably 2 ⁇ m to 2.5 ⁇ m. Displays with liquid crystal cells with smaller diagonals are particularly preferred, in particular in the range from 0.5 "to 6", particularly in the range from 1 "to 4".
- the liquid crystal switching elements preferably contain two ⁇ / 4 layers or, particularly preferably, a ⁇ / 2 layer.
- the two ⁇ / 4 layers can be used on different sides of the liquid crystal layer, but they can also be on the same side of the liquid crystal layer.
- the optical delay of the liquid crystal layer [(d- ⁇ n) c] is significantly different from 0.14 ⁇ m, especially if it is in the range from 0.07 ⁇ m to 0.12 ⁇ m or from 0.16 ⁇ m to 0, 21 ⁇ m, the use of two ⁇ / 4 layers or one ⁇ / 2 layer is necessary.
- This second preferred embodiment places high demands both on the birefringence of the liquid crystal material and on the layer thickness of the liquid crystal layer.
- the requirements for the layer thickness of the liquid crystal layer are somewhat alleviated by the lower layer thickness dependency of the optical properties of the switching elements.
- the layer thickness tolerance is also easier to maintain.
- the thin liquid crystal cells of this preferred embodiment have extremely short, short switching times.
- the liquid crystal switching elements according to the present application can be operated transmissively, transflectively or reflectively.
- the transmissive or transflective mode of operation is preferred, and the transmissive mode of operation is particularly preferred.
- Transflective displays enable the advantages of low power consumption of the reflective displays to be combined with good readability and low ambient brightness of the transmissive displays with backlighting.
- Dielectric or metallic layers can be used as reflectors.
- Metallic reflector layers are preferred. If metallic reflectors are used, a greater variation in the optical delay of the liquid crystal layer can be tolerated. Becomes a
- the optical delay of the liquid crystal layer is used essentially ⁇ / 4, especially in the switching elements without a birefringent layer.
- a dielectric reflector is preferably used, which preferably has a low proportion of depolarized reflection.
- Table 1 Particularly preferred combinations of the optical retardation of the liquid crystal layer and the double-breaking layer are summarized in the following table (Table 1). This table also shows the preferred positions of the polarizers both to one another and to the preferred direction of the liquid crystals.
- ⁇ / 2 plate in the table above explicitly includes two ⁇ / 4 plates.
- the angle ⁇ PD is preferably 0 ° +/- 5 °, particularly preferably 0 ° +/- 2 ° and very particularly preferably 0 ° +/- 1 °.
- the liquid crystal switching elements according to the present invention act as light valves when a voltage is applied. This is for the liquid crystal switching elements of the first preferred embodiment of the present application e.g. B. shown in Figures 1 and 2.
- the switching element In the case of crossed polarizers, the switching element is translucent in the voltage-free state, the “off state” (“normally white” or also called positive contrast).
- a threshold is first reached, above which the transmission begins to decrease. Then the transmission decreases almost linearly with increasing voltage over a relatively wide range of voltage. With higher voltage, the transmission tends to a limit value, saturation is achieved.
- the liquid crystal switching elements are preferably controlled in such a way that the optical delay of the liquid crystal layer when switching completely goes to 0 nm or at least essentially to 0 nm. Of course, this does not preclude gray levels with the required intermediate values.
- the display elements according to the present invention can contain further optical layers.
- These layers can be compensation layers, for example, which are used in particular with display elements with a twist of the liquid crystal layer different from 0 °, or else the light, for.
- B. a backlight collimating films such as the so-called “brightness enhancement films” (BEF) or cholesteric circular polarizers to utilize the otherwise absorbed by the polarizer half of the light from the backlight.
- BEF beamrightness enhancement films
- cholesteric circular polarizers to utilize the otherwise absorbed by the polarizer half of the light from the backlight.
- REPLACEMENT SHEET (RULE 26)
- a backlight with an approximately white spectral distribution is preferably used and the color is separated by a color filter.
- the individual liquid crystal switching elements are then used as light valves for the respective primary colors.
- the backlight can also be adapted to the spectral characteristics of the color filter in such a way that it has corresponding intensity maxima in the respective transmission ranges.
- the color display can also be achieved by double refraction effects.
- liquid-crystal switching elements according to the invention and in particular the reflective switching elements preferably operate in the “normally white mode” (for the polarizer position, see Figure 3 and the associated description).
- Liquid crystal mixtures which are used in the liquid crystal switching elements according to the invention preferably contain from 3 to 27, particularly preferably 10 to 21 and very particularly preferably 12 to 18 individual compounds.
- the individual compounds which are preferably used preferably each contain a 1,4'-rans-rans-bicyclohexylene unit of the sub-formula i:
- Z is a single bond, -CH 2 CH 2 - or -CF 2 CF 2 - and n 1 or 2.
- one of the two cyclohexane rings may also be replaced by
- REPLACEMENT SHEET RULE 26 it can also be replaced twice or, preferably, simply laterally fluorinated, 1,4-phenylene.
- the liquid crystal mixtures preferably contain one or more compounds having a structural unit of the formula i in which n is 2.
- liquid crystal mixtures used in the liquid crystal switching elements according to the invention preferably contain
- a component A consisting of compounds with 2 six-membered rings
- component B consisting of compounds with 3 six-membered rings and optionally
- a component C consisting of compounds with 4 six-membered rings.
- the liquid crystal mixtures preferably consist essentially of components A, B and optionally C.
- Particularly preferred liquid crystal mixtures contain one or more
- R 12 n-alkyl with 1 to 5 carbon atoms, 1 E-alkenyl, preferably vinyl or n-alkoxy with 1 to 6 carbon atoms
- Y 2 and Z 2 are independently H or F
- R 31 is n-alkyl or 1 E-alkenyl having 2 to 7, preferably 2 to 5, carbon atoms,
- Z 31 and Z 32 each have a single bond of Z 31 and Z 32 and -
- Ch 2 CH 2 - or -CF 2 CF 2 - preferably -CH 2 CH 2 -, but particularly preferably both a single bond
- Y 3 and Z 3 are independently H or F
- X 3 OCF 2 preferably both Y 3 and Z 3 F,
- X 3 OCF 3 preferably one of Y 3 and Z 3 F, the other H,
- Y 4 and Z 4 are independently H or F
- R 5 n-alkyl or 1 E-alkenyl with 2 to 5 carbon atoms
- Z 5 is a single bond or -CH 2 CH 2 -
- Y 5 and Z 5 are independently H or F
- R 71 and R 72 , R 81 and R 82 , R 91 and R 92 , R 10 and R 11 each independently of one another have the meaning given above for R 11 and R 12 in formulas I,
- X 10 , Y 10 and Z 10 and X 11 , Y 11 and Z 11 each independently of one another have the meaning given above for X 3 , Y 3 and Z 3 in formulas III.
- the liquid crystal mixtures according to the present application preferably contain 4 to 36 compounds, particularly preferably 6 to 25 compounds and very particularly preferably 7 to 20 compounds.
- Particularly preferred liquid crystal mixtures contain one or more compounds selected from the group of the following compounds in Table 3 and particularly preferably in each case one or more compounds of at least three, preferably of at least four, different formulas listed in Table 3 below.
- Table 3 Preferred compounds
- the temperature range of the nematic phase preferably ranges from -20 ° C to 60 ° C, particularly preferably from -30 ° C to 70 ° C and very particularly from -40 ° C to 80 ° C.
- the birefringence is preferably from 0.040 to 0.070, particularly preferably from 0.050 to 0.065 and very particularly preferably from 0.054 to 0.063.
- the rotational viscosity is preferably 60 to 170 m Pa s., Particularly preferably 80 to 150 m Pa s and very particularly preferably 90 to 139 m Pa s.
- the threshold voltage (V1 0 ) in the switching elements according to the invention is preferably 0.9 V to 2.7 V, particularly preferably 1.1 V to 2.5 V and very particularly preferably 1.2 V to 2.0 V. Total switching times for switching between
- V 10 and V 90 and back in the switching elements according to the invention are preferably at most 100 ms, particularly preferably at most 80 ms, very particularly preferably 60 ms or less.
- the total switching times are 50 ms or less, preferably 45 ms or less, particularly preferably 40 ms or less, in particular 40 ms or less and gans particularly preferably 30 ms or less.
- the preferred parameters of the liquid crystal mixtures can easily be seen by the person skilled in the art on the basis of the examples shown below.
- the preferred ranges of the physical properties of the liquid crystal mixtures and their combinations are those that are covered by the values of the examples.
- the liquid crystal mixtures particularly preferably consist essentially of compounds selected from the group of the compounds of forms I, II, II 'and III to XI.
- the liquid crystal media used in the liquid crystal switching elements according to the present invention preferably consist of 3 to 35 compounds, particularly preferably 4 to 25, very particularly preferably 5 to 20 and particularly preferably 6 to 15 compounds.
- the preferred d / P range is from -0.25 to 0.25.
- ad / P in the range from -0.1 to 0.1 is special of 0, preferred.
- d / P values with an amount of 0.1 to 0.25, particularly 0.15 to 0.24, are preferred.
- - ⁇ is 576 nm
- - V 0 capacitive threshold or Freedericksz threshold
- - ⁇ PP (identical to ⁇ p A ): angle between the transmission axes of the polarizers, - ⁇ PD : angle between the transmission axis of the polarizers and the fast axis of the birefringent layer,
- the specified voltage values are root mean square (rms) values, - "essentially 0" means, unless otherwise stated, 0 +/- 1, preferably 0 +/- 0.1 and particularly preferred 0 +/- 0.1,
- the rotational viscosity of the nematic liquid crystal mixture ZLI-4792 (Merck KGaA) at 20 ° C with the calibrated rotational viscometer was 133 mPa-s.
- Orientation layer AL-1054 from Japan Synthetic Rubber, Japan,
- Tilt angle 1 ° to 2 ° (determined with liquid crystal material ZLI-4792 der
- Twist angle 0 ° (glass plates rubbed antiparallel), d / P: 0 (undoped).
- test cells were determined in commercial devices from Autronic-Melchers, Düsseldorf, Germany (DMS 301 and DMS 703) and additionally in a self-made device from Merck KGaA, each using white
- the self-made device uses a photomultiplier as a detector and a filter to adapt the response sensitivity of the detector to the sensitivity curve of the human eye.
- the ⁇ / 4 layer was fixed as a plate in the self-made device from Merck KGaA in the beam path.
- a ⁇ / 4 film made of liquid crystalline polymer from Merck Ltd, Great Britain was used for the measurements with the DMS 703.
- liquid crystal compounds are designated by abbreviations.
- the coding of the structures is obvious and is carried out according to Tables A and B. All groups C n H 2n + 1 , C m H 2m + 1 C
- the coding in Table B is self-explanatory.
- Table A shows only the respective core frameworks of the structures. The individual compounds are followed by the name of the nucleus followed by a hyphen-separated name for the substituents Ri, R2, Li and L2, which is given below:
- liquid crystal mixtures of the present invention preferably contain
- a liquid crystal switching element with anti-parallel edge orientation and a polyimide orientation layer, a twist angle of 0 ° and a surface tilt angle of 1.4 ° was realized.
- the switching element contained a ⁇ / 4 layer and crossed polarizers, which took an angle of 45 ° to the rubbing direction of the substrates.
- the structure of the liquid crystal switching element corresponds to the structure shown in Figure 1.
- the optical delay of the liquid crystal layer was 0.277 ⁇ m.
- the composition of the liquid crystal mixture used is given in the following table, together with the properties of the mixture as such and the characteristic voltages in the switching element according to the invention.
- the liquid crystal switching element was examined for its transmission when the analyzer angle was varied. The result is shown in Figure 3.
- the optical delay was 277 nm. It can be seen that in the voltage-free state with parallel polarizers, ie in each case at angles ⁇ PP of 0 °, 180 ° and 360 °, minimal transmission occurs and that this minimal transmission goes down to almost 0%. These mutually identical polarization positions correspond to the "normally black" mode. In contrast, with crossed polarizers, ie at angles ⁇ PP of 90 ° and 270 °, which correspond to the "normally white” mode, the maximum transmission occurs.
- Figure 2 shows the definition of the viewing angle in the plane of the display ( ⁇ or ⁇ ') and perpendicular to the perpendicular ( ⁇ ).
- the maximum transmission in the fully switched state is approximately 45%. It is essentially determined by the transmission of the polarizers. With high control voltages of approx. 6 to 7 V, a very high transmission is achieved. The minimum transmission mainly depends on the degree of polarization of the polarizers used.
- the spectral distribution of the transmission was then determined for the switching element driven with different voltages.
- Example 1 and Figure 8a that of the conventional TN switching element of Comparative Example 1.
- the iso transmission lines are staggered at intervals of 10% absolute.
- the darkest area corresponds to a transmission from 0% to 10% inclusive, the next gray area from more than 10% to 20% inclusive, the light gray area from more than 20% to 30% inclusive and so on, always with the lower limit exclusively and the upper limit is inclusive.
- the other areas with a transmission above 30% are not tinted gray.
- the two drive voltages for the cell of the present example were 1, 13 V and 2.64 V. The result is shown in Figure 9a).
- the individual curves successively stand for contrast ratios of 7, 5, 3, 2 and 1 from inside to outside.
- the maximum contrast ratio here was 9.6 and the minimum contrast ratio was 0.58.
- Figure 9c shows the results for the TN switching element of comparative example 1 for direct comparison.
- the individual curves successively stand for contrast ratios of 10, 7, 5, 3, 2 and 1 from inside to outside.
- a clear inverse contrast occurs.
- Switching times for different switching voltages were also determined. Exemplary results are listed in Table 4. Particularly in comparison with the results for the TN switching element of Comparative Example 1, the surprisingly short switching times of the switching elements according to the invention are remarkable. The switching times were determined under three different control conditions. In the first two series, the switching times for a change from a voltage of 0 volts to a fixed value and back were determined. In the first two series, the switching times for a change from a voltage of 0 volts to a fixed value and back were determined. In the first
- a liquid crystal switching element was produced and investigated analogously to Example 1, but now a TN switching element with an optical delay of 0.50 ⁇ m, without another birefringent layer, with crossed polarizers, which were also crossed to the rubbing directions.
- composition of the liquid crystal mixture used is shown in the following table, as are the properties of the mixture and the characteristic voltages of the TN element.
- Figure 8a shows the isotransmission results for this comparative example 1, which were obtained under the same conditions as the results for example 1. The results have already been discussed in example 1.
- Figure 9c shows the isocontrast results obtained under the same conditions as in Example 1.
- the two driving voltages were 1, 07 and V 1, V 71, and V 0 corresponding V ⁇ 90th
- the individual curves successively stand for contrast ratios of 10, 7, 5, 3, 2 and 1 from inside to outside.
- the maximum contrast ratio was 15, the minimum contrast ratio 0.43. So it is obvious
- a switching element like that of Example 1 was produced, the construction with one exception. No ⁇ / 4 layer was used.
- the switching element had almost the same electro-optical characteristics, both in the self-made device and in the device from Autronic-Melchers, with a viewing angle of 0 ° as that of Example 1.
- the maximum contrast was practically identical to that of Example 1.
- Example 1 The viewing angle dependency of the contrast was excellent when viewed visually. This was confirmed by measuring the isocontrast curves under the same conditions as in Example 1. As in Example 1, the two control voltages were 1, 13 V and 2.64 V. The result is shown in Figure 9b). The individual curves successively stand for the same contrast ratios from inside to outside as in Figure 9a), whereby only the last curve is omitted, i.e. for 7, 5, 3 and 2. The maximum contrast ratio here was 10.0, the minimum 1, 08 , So there was no inverse contrast at all under these conditions.
- example 2 clearly has the broader, i.e. better, viewing angle range.
- the element of example 2 is also slightly superior to that of example 1 with regard to the integral consideration.
- the angle range of the element of example 1 is significantly better with regard to the viewing angle ⁇ . This can be seen particularly in the area of the quadrant with the lowest contrast.
- the viewing angle range of the switching element of Example 1 is significantly more centrosymmetric.
- a switching element was implemented as in example 1 with a ⁇ / 4 plate.
- ZLI-4792 a commercial product of Merck KGaA, was used here as the liquid crystal material. This material has a birefringence of
- the layer thickness of the liquid crystal layer was 5.1 ⁇ m.
- the TN switching element can be clearly recognized from a voltage of about 2.4 volts.
- the characteristic curve of the switching element according to the invention is significantly flatter, that is to say it has a lower slope (also called steepness), which is more suitable for displaying gray levels.
- no inverse contrast occurs at all in the switching element according to the invention.
- the switching element according to the invention is much better suited for displaying gray levels and in particular color levels.
- composition conc. /%. characteristics
Landscapes
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Mathematical Physics (AREA)
- Liquid Crystal (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU66954/00A AU6695400A (en) | 1999-07-22 | 2000-07-19 | Liquid crystal switching member and lcd device |
US10/031,494 US6781664B1 (en) | 1999-07-22 | 2000-07-19 | Liquid-crystal switching elements comprising a liquid-crystal layer which has extremely low optical retardation and liquid-crystal displays containing them |
KR1020027000687A KR20020026355A (ko) | 1999-07-22 | 2000-07-19 | 액정 스위칭 성분 및 액정 디스플레이 장치 |
EP00954531A EP1196815A1 (de) | 1999-07-22 | 2000-07-19 | Flüssigkristallschaltelement und flüssigkristalldarstellungseinrichtung |
JP2001512995A JP2003505739A (ja) | 1999-07-22 | 2000-07-19 | 液晶スイッチング素子と液晶ディスプレイ装置 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19933571.0 | 1999-07-22 | ||
DE19933571 | 1999-07-22 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2001007962A1 true WO2001007962A1 (de) | 2001-02-01 |
Family
ID=7915136
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2000/006879 WO2001007962A1 (de) | 1999-07-22 | 2000-07-19 | Flüssigkristallschaltelement und flüssigkristalldarstellungseinrichtung |
Country Status (6)
Country | Link |
---|---|
US (1) | US6781664B1 (de) |
EP (1) | EP1196815A1 (de) |
JP (1) | JP2003505739A (de) |
KR (1) | KR20020026355A (de) |
AU (1) | AU6695400A (de) |
WO (1) | WO2001007962A1 (de) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2393262A (en) * | 2002-09-20 | 2004-03-24 | Merck Patent Gmbh | :New mode LCD comprising an A-plate or O-plate retardation film |
WO2004033584A1 (de) * | 2002-10-07 | 2004-04-22 | Merck Patent Gmbh | Flüssigkristalline medien enthaltend polymere |
US6764723B2 (en) * | 2001-04-20 | 2004-07-20 | Merck Patent Gmbh | Liquid-crystalline medium |
US7081280B2 (en) * | 1998-12-22 | 2006-07-25 | Merck Patent Gmbh | Liquid-crystalline medium |
DE10111572B4 (de) * | 2000-03-23 | 2009-11-12 | Merck Patent Gmbh | Flüssigkristallines Medium und seine Verwendung |
WO2011144299A1 (en) * | 2010-05-19 | 2011-11-24 | Merck Patent Gmbh | Optical switch element comprising a liquid-crystalline medium |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3705184B2 (ja) * | 2001-10-24 | 2005-10-12 | セイコーエプソン株式会社 | 液晶装置及び電子機器 |
JP2006317656A (ja) * | 2005-05-12 | 2006-11-24 | Dainippon Printing Co Ltd | 異方性光学素子 |
CN101580715B (zh) * | 2009-05-13 | 2013-11-20 | 江苏和成显示科技股份有限公司 | 具有极低折射率的液晶组合物 |
GB201009488D0 (en) * | 2010-06-07 | 2010-07-21 | Merck Patent Gmbh | Switch element comprising a liquid-crystaline medium |
TW201323997A (zh) * | 2011-12-02 | 2013-06-16 | Chimei Innolux Corp | 液晶顯示裝置 |
TW202235979A (zh) * | 2021-01-28 | 2022-09-16 | 美商元平台技術有限公司 | 具有背反射抑制的顯示面板 |
US11493800B2 (en) | 2021-01-28 | 2022-11-08 | Meta Platforms Technologies, Llc | Display panel with backreflection suppression comprising first and second birefringent layers and a reflectivity layer |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0463816A2 (de) * | 1990-06-22 | 1992-01-02 | Fujitsu Limited | Reflektive Flüssigkristallvorrichtung |
EP0727691A1 (de) * | 1995-02-14 | 1996-08-21 | Sagem S.A. | Flüssigkristall-Anzeigevorrichtung mit aktiver Matrix und homogen ausgerichtetem, nicht verdrillten Flüssigkristall, sowie Kompensation der Verzögerung |
EP0803758A2 (de) * | 1996-04-26 | 1997-10-29 | Hitachi, Ltd. | Flüssigkristallanzeige |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE727691C (de) | 1936-10-07 | 1942-11-09 | Dr Karl Brandt | Verfahren zur Herstellung von physiologisch wertvollen loeslichen Amidierungsprodukten aus Kohlenhydraten und Saeureamiden |
AU7095996A (en) * | 1995-09-26 | 1997-04-17 | Chisso Corporation | Homeotropic sprayed-nematic liquid crystal display device |
JP3282986B2 (ja) * | 1996-02-28 | 2002-05-20 | 富士通株式会社 | 液晶表示装置 |
KR100679790B1 (ko) * | 1999-02-17 | 2007-02-07 | 메르크 파텐트 게젤샤프트 미트 베쉬랭크터 하프퉁 | 활성 매트릭스 적용을 위한 네마틱 액정 조성물 및 반사성 액정 디스플레이 |
-
2000
- 2000-07-19 KR KR1020027000687A patent/KR20020026355A/ko not_active Application Discontinuation
- 2000-07-19 EP EP00954531A patent/EP1196815A1/de not_active Withdrawn
- 2000-07-19 JP JP2001512995A patent/JP2003505739A/ja active Pending
- 2000-07-19 AU AU66954/00A patent/AU6695400A/en not_active Abandoned
- 2000-07-19 WO PCT/EP2000/006879 patent/WO2001007962A1/de not_active Application Discontinuation
- 2000-07-19 US US10/031,494 patent/US6781664B1/en not_active Expired - Fee Related
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0463816A2 (de) * | 1990-06-22 | 1992-01-02 | Fujitsu Limited | Reflektive Flüssigkristallvorrichtung |
EP0727691A1 (de) * | 1995-02-14 | 1996-08-21 | Sagem S.A. | Flüssigkristall-Anzeigevorrichtung mit aktiver Matrix und homogen ausgerichtetem, nicht verdrillten Flüssigkristall, sowie Kompensation der Verzögerung |
EP0803758A2 (de) * | 1996-04-26 | 1997-10-29 | Hitachi, Ltd. | Flüssigkristallanzeige |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7081280B2 (en) * | 1998-12-22 | 2006-07-25 | Merck Patent Gmbh | Liquid-crystalline medium |
DE10111572B4 (de) * | 2000-03-23 | 2009-11-12 | Merck Patent Gmbh | Flüssigkristallines Medium und seine Verwendung |
US6764723B2 (en) * | 2001-04-20 | 2004-07-20 | Merck Patent Gmbh | Liquid-crystalline medium |
GB2393262A (en) * | 2002-09-20 | 2004-03-24 | Merck Patent Gmbh | :New mode LCD comprising an A-plate or O-plate retardation film |
GB2393262B (en) * | 2002-09-20 | 2006-03-29 | Merck Patent Gmbh | New mode lcd comprising two O plate retardation films |
WO2004033584A1 (de) * | 2002-10-07 | 2004-04-22 | Merck Patent Gmbh | Flüssigkristalline medien enthaltend polymere |
WO2011144299A1 (en) * | 2010-05-19 | 2011-11-24 | Merck Patent Gmbh | Optical switch element comprising a liquid-crystalline medium |
US9023238B2 (en) | 2010-05-19 | 2015-05-05 | Merck Patent Gmbh | Optical switch element comprising a liquid-crystalline medium |
Also Published As
Publication number | Publication date |
---|---|
KR20020026355A (ko) | 2002-04-09 |
AU6695400A (en) | 2001-02-13 |
JP2003505739A (ja) | 2003-02-12 |
EP1196815A1 (de) | 2002-04-17 |
US6781664B1 (en) | 2004-08-24 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
DE19813490B4 (de) | Verfahren zur Erzeugung von zwei Domänen innerhalb einer Flüssigkristallschicht, LCD-Vorrichtung und Verfahren zur Herstellung dieser Vorrichtung | |
DE19829226B4 (de) | Flüssigkristallanzeige und Verfahren zu ihrer Herstellung | |
EP0509025B1 (de) | Elektrooptisches flüssigkristallschaltelement | |
DE69325328T2 (de) | Polymer dispergierter Flüssigkristallfilm, Flüssigkristallanzeige und Verfahren zur Herstellung | |
DE68923768T2 (de) | Flüssigkristall-Anzeigevorrichtung mit verbesserten Winkelblick-Eigenschaften. | |
DE69816481T2 (de) | Bistabile nematische flüssigkristallvorrichtung | |
DE69328852T2 (de) | Elektrooptische Flüssigkristall-Vorrichtung | |
EP0131216B1 (de) | Flüssigkristallanzeige | |
DE69432654T2 (de) | Flüssigkristall-Anzeige und -vorrichtung | |
DE69524472T2 (de) | Flüssigkristallanzeigevorrichtung mit einem Paar Verzögerungsfilmen auf einer Seite der Flüssigkristallschicht | |
DE60206964T2 (de) | Transflektive flüssigkristallanzeigevorrichtung | |
DE68916294T2 (de) | Elektrooptische Einrichtung mit einem ferroelektrischen Flüssigkristall und Methode zu deren Herstellung. | |
DE3543235C2 (de) | ||
KR100745115B1 (ko) | 액정표시장치 | |
DE102005030604B4 (de) | LCD mit großem Betrachtungswinkel sowie Herstellverfahren für dieses | |
DE3888519T2 (de) | Flüssigkristall-anzeigevorrichtung. | |
DE3887436T2 (de) | Flüssigkristall-Anzeigetafel. | |
DE60021399T2 (de) | Flüssigkristallvorrichtung und Display | |
DE102010056535A1 (de) | Flüssigkristallanzeige-Vorrichtung | |
WO2001007962A1 (de) | Flüssigkristallschaltelement und flüssigkristalldarstellungseinrichtung | |
DE68918192T2 (de) | Doppelschicht-Flüssigkristall-Anzeigevorrichtung. | |
DE10331298A1 (de) | Flüssigkristallanzeigevorrichtung mit cholesterischen Flüssigkristall | |
DE69216548T2 (de) | Flüssigkristallvorrichtung und Anzeigevorrichtung | |
EP0376029B1 (de) | Flüssigkristalldisplay für Schwarz/Weiss-Darstellung | |
DE102006062859B4 (de) | IPS-Flüssigkristallanzeigevorrichtung |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AL AM AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ DE DK DM EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2000954531 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1020027000687 Country of ref document: KR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 10031494 Country of ref document: US |
|
WWP | Wipo information: published in national office |
Ref document number: 1020027000687 Country of ref document: KR |
|
WWP | Wipo information: published in national office |
Ref document number: 2000954531 Country of ref document: EP |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 2000954531 Country of ref document: EP |