JPH11223814A - Liquid crystal display - Google Patents

Abstract

(57) [Problem] To provide a liquid crystal display having a liquid crystal region in which liquid crystal molecules are axially symmetrically aligned in each picture element region even on a large screen, and excellent in omnidirectional viewing angle characteristics, and high-contrast liquid crystal display without roughness. Provide equipment. A liquid crystal layer is provided between a pair of substrates.
Is pinched. Liquid crystal layer 40 of a pair of substrates 32 and 34
Transparent electrodes 31 and 33 each made of ITO are formed on the surface in contact with the transparent electrode 31, and a convex portion 36 made of a conductive material is formed on at least one of the transparent electrodes 31 in contact with the transparent electrode 31. Have been. Further, vertical alignment layers 38a and 38b are formed thereon. Axisymmetric alignment A region exhibiting an axial symmetry when a centering voltage is applied is defined by the convex portion 36. Therefore, the liquid crystal molecules 42 are axially symmetrically aligned around the axially symmetric alignment central axis 44 in the picture element region defined by the protrusion 36.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a large-sized liquid crystal display device suitable for application to a high-definition television such as an HDTV, a CAD display, and the like.

[0002]

2. Description of the Related Art As a method for improving the viewing angle characteristics of a liquid crystal display device, a display mode (axially symmetric A) in which liquid crystal molecules are aligned in an axially symmetric manner for each picture element.
lighted Microcell Mode: ASM
Mode) is disclosed in JP-A-7-120728. This method is a technology that uses a phase separation from a mixture of a liquid crystal material and a photo-curing resin to align liquid crystal molecules in an axially symmetrical manner. This is a p-type display mode in which liquid layer molecules oriented in a vertical direction are oriented perpendicular to the substrate.

[0003] Another technique is disclosed in Japanese Patent Application No. 8-341.
At 590, there is a pair of substrates each having an electrode, and a liquid crystal layer sandwiched between the pair of substrates, wherein the liquid crystal molecules of the liquid crystal layer have a negative dielectric anisotropy and have an axially symmetric alignment central axis. When no output voltage is applied, the liquid crystal molecules are vertically aligned with respect to the pair of substrates. When an axis-symmetric alignment center output voltage is applied, the liquid crystal molecules are axially symmetrical in each of a plurality of pixel regions. There is disclosed a liquid crystal display device that is aligned in a liquid crystal display. Since the liquid crystal display device of the present proposal operates in a normally black mode, a higher contrast can be obtained as compared with a conventional ASM mode liquid crystal display device, and it can be easily manufactured.

FIG. 9 is a schematic view of a conventional n-type ASM liquid crystal display device. 9B is a plan view thereof, and FIG. 9A is a cross-sectional view taken along line XX of FIG. 9B.

This liquid crystal display device has a glass substrate 101 and a glass substrate 102 which are disposed opposite to each other at a predetermined interval, and a liquid crystal material having a negative dielectric anisotropy is provided between the substrates 101 and 102. Liquid crystal layer 109 is sandwiched. On the inner surface of the glass substrate 102 on the upper side of the figure, a signal electrode 104 is formed in a stripe shape, and a vertical alignment layer 105 of polyimide or the like is formed on almost the entire surface so as to cover this.

On the inner surface of the lower glass substrate 101, a signal electrode 103 is formed in a stripe shape so as to intersect with the signal electrode 104, and a grid-like partition wall 106 is further formed thereon. A columnar protrusion 107 is selectively provided on the partition wall 106 so that the glass substrate
2 is provided.

The partition wall 106 is formed by patterning, for example, by exposing and developing a photosensitive resin through a mask. Similarly to the partition wall 106, the columnar projections 107 are formed by applying a photosensitive resin through the mask, for example. Patterning by exposure and development. On these signal electrodes 103, partition walls 106 and columnar projections 107,
A vertical alignment layer 105 made of polyimide or the like is covered.

In this technique, the position and size of the liquid crystal region 108 are defined by the partition wall 106.
A portion surrounded by the partition wall 106 becomes a liquid crystal region 108, and when no voltage is applied between the two signal electrodes 103 and 104, the liquid crystal molecules in the liquid crystal region 108 form a pair of substrates 101 and
The liquid crystal molecules are oriented substantially perpendicular to the liquid crystal 102, and the liquid crystal molecules are oriented axially symmetrically in each liquid crystal region 108 when a voltage is applied. Also,
Columnar projection 1 existing between partition wall 106 and substrate 102
07 has a function of keeping the cell thickness constant because it is in contact with the substrate 102.

The configuration and operation principle of the liquid crystal display device will be described with reference to FIG. 10 (a) and 10 (b) show the results when no axially symmetric alignment centering voltage is applied, and FIGS. 10 (c) and 10 (d) show the results when the axially symmetric alignment centering voltage is applied. 10 (a) and 10 (c) are cross-sectional views, and FIGS. 10 (b) and 10 (d) show the results of observing the top surface with a crossed Nicols polarizing microscope.

In this liquid crystal display device, a liquid crystal layer 140 composed of liquid crystal molecules 142 having negative dielectric anisotropy is sandwiched between a pair of substrates 132 and 134. Transparent electrodes 131 and 133 are formed on the surfaces of the pair of substrates 132 and 134 that are in contact with the liquid crystal layer 140, respectively, and further, vertical alignment layers 138a and 138b are formed thereon. In addition, a projection 136 is formed on a surface of at least one of the pair of substrates 132 and 134 that is in contact with the liquid crystal layer 140.

As will be described later, a region which exhibits an axially symmetric orientation when an axially symmetric orientation centering voltage is applied is defined by a convex portion 136. Therefore, as shown in FIG. 10C, the protrusion 136 is centered on the axis symmetric alignment central axis 144.
The liquid crystal molecules 142 are axially symmetrically aligned in the pixel region defined by the above.

When no axial centering voltage is applied to the liquid crystal molecules 142, the liquid crystal molecules 142 are aligned in the direction perpendicular to the substrate by the alignment regulating force of the vertical alignment layer, as shown in FIG. Observation of the pixel region in the state where no voltage is applied to the center axis of the axially symmetric alignment by a polarizing microscope in a crossed Nicol state shows a dark field (normally black mode) as shown in FIG. 10B. When an axisymmetric alignment centering voltage is applied, liquid crystal molecules 14 having negative dielectric anisotropy are applied.
In FIG. 10, since a force acts to orient the major axis of the liquid crystal molecules perpendicular to the direction of the electric field, the liquid crystal molecules are inclined from the direction perpendicular to the substrate as shown in FIG. 10C (halftone display state). Observing the picture element region in this state with a crossed Nicol state polarizing microscope,
As shown in FIG. 10D, an extinction pattern is observed in a direction along the polarization axis.

FIG. 11 shows a voltage transmittance curve of the liquid crystal display device.

As the voltage is applied, the transmittance gradually increases, and when the voltage further increases, the transmittance reaches saturation. The voltage at which the transmittance is saturated is called a saturation voltage (Vst). The voltage at which the transmittance becomes 10% relative to the transmittance at Vst (saturation voltage) is called Vth (threshold voltage). When a voltage is applied from a state where no voltage is applied, the liquid crystal molecules tilt from a direction perpendicular to the substrate,
Since the falling direction is not uniquely determined, a plurality of axially symmetric alignment central axes are formed in the liquid crystal region exhibiting the axially symmetric alignment defined by the protrusions 136. A state in which a plurality of axis-symmetric alignment central axes exist is an unstable alignment state, and the transmittance is not stable. When the voltage of １ ／ Vth or more is continuously applied, the plurality of axially symmetric alignment central axes becomes one for each liquid crystal region defined by the convex portion 136. When the voltage applied to the liquid crystal layer 140 is between 1/2 Vth and Vst, the transmittance reversibly changes within the operating range shown in FIG. In a state where a voltage of about 1/2 Vth is applied, the liquid crystal molecules are substantially vertically aligned with respect to the substrate, and are in an axially symmetric alignment state when a voltage of 1/2 Vth or more is applied, that is, in an axially symmetric alignment. It stores the symmetry with respect to the central axis. However, when no voltage is applied or when the applied voltage is Ｖ Vth
When the temperature becomes lower than that, the liquid crystal molecules are aligned substantially perpendicularly to the substrate and return to a state in which the axis-symmetric alignment state is not stored. Even if a voltage of Ｖ Vth or more is applied again from this state, a plurality of axially symmetric alignment central axes are once formed. For example, when an n-type liquid crystal material is injected into a liquid crystal cell, the same behavior is exhibited.

As described above, in the liquid crystal display device, when no voltage is applied, the liquid crystal molecules are oriented in a direction perpendicular to the substrate to display black, and when a voltage is applied, the liquid crystal molecules are formed in each pixel region. It operates in a normally black mode in which the display is in a state of axial symmetry with respect to the center axis of the symmetric alignment and white display is obtained. However, since a plurality of axially symmetric center axes are formed immediately after the application of the voltage, the operation becomes unstable when the black state is displayed when no voltage is applied. In order to perform a stable operation in the display mode in this liquid crystal display device, it is desirable to form one axially symmetric alignment central axis for each picture element region before performing the display operation.

In order to form one axially symmetric alignment central axis for each picture element region before performing the display operation,
A constant voltage, that is, a voltage of 1/2 Vth or more may be applied. In this way, a single axially symmetric alignment center axis is formed for each picture element region, and a stable axially symmetric alignment state can be realized during white display. However, once the voltage is not applied, the initial state returns to the unstable state in which a plurality of axially symmetric alignment central axes are formed. Instead, a constant voltage, that is, a voltage near 1/2 Vth is applied. In this display mode, an operating voltage is used in a voltage range (a voltage not less than 1/2 Vth and not more than Vst) in which a stable axially symmetric alignment state can be obtained.

Further, at the time of applying a voltage, in order to stably align the liquid crystal molecules in each picture element region in an axially symmetric manner, at least one of the substrates is provided with a surface in contact with the liquid crystal layer in a region corresponding to the liquid crystal region. A technique of providing an axially symmetric alignment fixed layer made of a polymer material is disclosed. The formation of the axially symmetric alignment fixed layer is realized by disposing a precursor mixture composed of at least a liquid crystal material and a photocurable material between a pair of substrates and curing the mixture while applying a voltage. it can. The applied voltage may be not less than 1/2 Vth at which the above-mentioned axially symmetric alignment is stabilized and not more than Vst.

[0018]

However, when applied to the above-mentioned conventional large-sized display device, there are the following problems.

In general, ITO is used for a transparent electrode. The ITO has a high resistivity and the applied voltage to the liquid crystal layer in the panel becomes uneven as the screen becomes larger.

In the display mode of the above-mentioned conventional technique, the operating voltage is used in a range of a voltage (a voltage not less than 1/2 Vth and not more than Vst) in which a stable axially symmetric alignment state can be obtained. When the screen is enlarged, the non-uniformity of the voltage applied in the black display becomes large in the panel, and there is a pixel in which a voltage of less than 1/2 Vth is applied and a stable axially symmetric alignment state cannot be obtained. In addition, the display becomes uneven and causes roughness. In order to eliminate display unevenness, it was necessary to increase the driving voltage.

Further, according to a further conventional technique, at least one of the substrates is cured by applying a voltage to a precursor mixture composed of a liquid crystal material and a photocurable material, thereby curing the mixture corresponding to the liquid crystal region of at least one of the substrates. An axially symmetric alignment fixed layer made of a polymer material is formed on the surface in contact with the liquid crystal layer. In the step of forming the axis-symmetric alignment fixed layer, it is important that the liquid layer molecules are tilted at a certain angle (tilt angle) with respect to the normal direction of the substrate. To tilt the liquid crystal molecules at a certain angle with respect to the normal direction of the substrate, a voltage may be applied. The applied voltage is Ｖ Vth at which the axially symmetric alignment is stabilized in the display mode described above.
Above, it is only necessary to be Vst or less. When the screen becomes larger, the applied voltage at the time of forming the above-mentioned axially symmetric alignment fixed layer becomes more uneven in the panel, and only a voltage of 1/2 Vth or less is applied at the time of forming the above-mentioned axially symmetric alignment fixed layer. A liquid crystal panel is manufactured without increasing the number of pixels, and the alignment is not fixed.At the time of display, the axially symmetric alignment state becomes unstable, and the display becomes uneven, causing roughness, and the rising time is delayed. There was a problem.

The present invention has been made in order to solve such problems of the prior art, and has a liquid crystal region in which liquid crystal molecules are axially symmetrically aligned for each pixel region even on a large screen. An object of the present invention is to provide a high-contrast liquid crystal display device having excellent azimuthal viewing angle characteristics and having no roughness.

[0023]

A liquid crystal display device according to the present invention has a pair of substrates and a liquid crystal layer sandwiched between the pair of substrates, and a transparent electrode is formed on the pair of substrates. The liquid crystal layer has at least one picture element region for each picture element, and in a liquid crystal display device in which liquid crystal molecules in the picture element area are axially symmetrically aligned around an axially symmetric alignment central axis, A convex portion substantially surrounding the picture element region is formed on the surface of the substrate on the liquid crystal layer side so as to be in contact with the transparent electrode, and the convex portion has a region made of a conductive material. And the conductive region is in contact with the transparent electrode, thereby achieving the above object.

In the liquid crystal display device according to the present invention, the liquid crystal molecules of the liquid crystal layer have a negative dielectric anisotropy, and when no voltage is applied, the liquid crystal molecules are oriented substantially perpendicular to the pair of substrates.
At the time of applying a voltage, the liquid crystal molecules can be arranged to be axially symmetrical about the central axis of the axially symmetric alignment for each of the plurality of picture element regions.

In the liquid crystal display device according to the present invention, the transparent electrodes formed on at least one of the pair of substrates may have a stripe shape.

In the liquid crystal display device according to the present invention, the conductive region of the projection may be formed of a single-layer metal thin film or a multi-layer metal thin film.

[0027] In the liquid crystal display device of the present invention, the projection may include a conductive region and an insulating layer, and the insulating layer may be laminated on the conductive region.

[0028] In the liquid crystal display device of the present invention, the projection may include a conductive region and an insulating layer, and the insulating layer may be formed to cover the conductive region.

In the liquid crystal display device of the present invention, the metal thin film may be composed of aluminum, chromium, nickel, molybdenum, titanium, copper, silver or gold, or an alloy of two or more of these. .

In the liquid crystal display device according to the present invention, it is preferable that the width of the convex portion is 5 μm or more and 20 μm or less.

In the liquid crystal display device according to the present invention, it is preferable that the height of the projection is not less than 20% and not more than 80% of the thickness of the liquid crystal layer.

In the liquid crystal display device according to the present invention, it is preferable that the thickness of the transparent electrode is in a range of 700 Å to 4000 Å.

In the liquid crystal display device of the present invention, it is preferable that the surface resistivity of the convex portion is in the range of 0.5 ohm / square to 2.0 ohms / square.

Hereinafter, the operation of the present invention will be described.

In the present invention, the position and size of the picture element region of the liquid crystal layer are defined by the presence of the convex portion substantially surrounding the picture element region, and the liquid crystal molecules in the liquid crystal region are axially symmetric. Orientation is oriented symmetrically with respect to the center axis. At this time, since the conductive region of the protrusion is formed so as to be in contact with the transparent electrode, the conductive region of the protrusion functions as an auxiliary electrode of the transparent electrode, and as a result, the resistance of the electrode is reduced. it can. As a result, non-uniformity in the liquid crystal panel of the operating voltage and the applied voltage when the axis-symmetric alignment fixed layer is formed is reduced, and a uniform and stable axis-symmetric alignment state can be realized in the liquid crystal panel. In addition, the display quality of the liquid crystal display device can be improved.

Further, by forming the conductive region of the convex portion with a metal thin film, the convex portion can be accurately formed by inexpensive wet etching.

The conductive region of the projection can be formed of a multilayer metal thin film. For example, if the transparent electrode is IT
O, when the conductive region of the projection is aluminum or an alloy of aluminum, a metal thin film is further formed on the conductive region on the side in contact with the transparent electrode;
Is greater than the difference between the reduction potential of
By reducing the difference between the reduction potential of TO and the oxidation potential of the metal thin film formed on the side in contact with the transparent electrode, an oxidation-reduction reaction between ITO and aluminum occurs in a developing process during a photolithography process of patterning the aluminum thin film. Can prevent the occurrence of so-called electrolytic corrosion reaction, which can cause the conductive region of the convex part to be patterned with a positive resist, enabling finer processing and realizing higher definition of the liquid crystal display device. it can. For example, a thin film of molybdenum or a molybdenum alloy can be used as the metal thin film formed on the side in contact with the transparent electrode.

By forming the convex portion into a multilayer structure in which an insulating layer is laminated on the conductive region, it is possible to improve the adhesion to an alignment film formed on the convex portion. Further, it is possible to prevent a vertical leak between the convex portion and the transparent electrode formed on the other substrate.

As the insulating layer, the process can be simplified by using a photoresist used for patterning and forming the conductive region without peeling it off without forming a new film. .

By covering the upper surface and the side surfaces of the conductive region of the convex portion with the insulating layer, it is possible to prevent the disorder of the alignment of the liquid crystal molecules due to the lateral electric field generated between the conductive regions of the adjacent convex portion. .

[0041]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a basic configuration of a liquid crystal display device according to the present invention will be described with reference to FIG.

As shown in FIG. 1A, the structure of this liquid crystal display device is such that a liquid crystal layer 40 composed of liquid crystal molecules 42 having a negative dielectric anisotropy is sandwiched between a pair of substrates 32 and 34. I have. Transparent electrodes 31 and 33 made of ITO are provided on the surfaces of the pair of substrates 32 and 34 on the side in contact with the liquid crystal layer 40, respectively.
Is formed, and on at least one of the transparent electrodes 31, a convex portion 36 made of a conductive material is formed in contact with the transparent electrode 31. Further, a vertical alignment layer 38 is formed thereon.
a and 38b are formed.

As a material of the convex portion 36, it is preferable to use a simple substance of aluminum, chromium, nickel, molybdenum, titanium, copper, silver or gold, or an alloy of two or more of these. The reason is that the volume resistance is smaller than that of ITO.

Further, the width of the convex portion 36 is 5 μm or more and 20 μm or more.
The reason for this is that if it is smaller than 5 μm, problems such as disconnection are likely to occur, and if it exceeds 20 μm, the aperture ratio will be significantly reduced.

When the height of the convex portion 36 is set to 20% or more and 80% or less of the thickness of the liquid crystal layer, when the height is smaller than 20%, no axially symmetric alignment is formed, and the height exceeds 80%. In this case, a short circuit occurs between the upper and lower substrates.

Further, the reason why the thickness of the transparent electrode is set within the range of 700 Å to 4000 Å is that if the thickness is smaller than 700 Å,
This is because the transparent electrode is easily peeled off from the glass substrate, and if it exceeds 4000 Å, the light transmittance is remarkably deteriorated.

The reason why the surface resistivity of the convex portion is in the range of 0.5 ohm / square to 2.0 ohms / square is as follows.
In order to make it smaller than 0.5 ohm / □, the width of the convex portion must be increased unnecessarily, or the height of the convex portion must be increased, so that the aperture ratio becomes low or the other substrate becomes It causes vertical leakage between the formed transparent electrode and
If it exceeds 2.0 ohms / square, it will not be possible to realize low resistance.

In the liquid crystal display device having this configuration, a region that exhibits an axially symmetric alignment when an axially symmetric alignment center axis setting voltage is applied is defined by the convex portion 36. Therefore, FIG.
As shown in (c), the liquid crystal molecules 42 are axially symmetrically aligned around the axially symmetric alignment central axis 44 in the picture element region defined by the protrusion 36.

When no axially symmetric alignment centering voltage is applied, as shown in FIG. 1A, the liquid crystal molecules 42 are aligned in the direction perpendicular to the substrate by the alignment control force of the vertical alignment layer. Observation of the picture element region in the state where no voltage is applied to the axially symmetric alignment center axis by a polarization microscope in a crossed Nicol state shows a dark field (normally black mode) as shown in FIG. 1B. When an axially symmetric alignment centering voltage is applied, a force acts on the liquid crystal molecules 42 having negative dielectric anisotropy so that the long axes of the liquid crystal molecules are perpendicular to the direction of the electric field. As shown in ()), it is inclined from the direction perpendicular to the substrate (halftone display state). When the picture element region in this state is observed with a crossed Nicol state polarizing microscope, an extinction pattern is observed in a direction along the polarization axis as shown in FIG.

As described above, the liquid crystal display device having this configuration has the convex portion 36 so as to surround the picture element region. The thickness of the liquid crystal layer 40 (cell gap) without the protrusion 36
Is uniform, the liquid crystal domains (continuously aligned regions:
Since the position or size at which a disclination line is not formed cannot be specified, a random alignment state is obtained, and a halftone display is rough.

By forming the convex portion 36 as in the present invention, the position and size of the liquid crystal region exhibiting the axially symmetric alignment are defined. The convex portion 36 controls the thickness of the liquid crystal layer 40 and is formed to weaken the interaction of liquid crystal molecules between picture element regions. The thickness of the liquid layer 40 is such that the thickness (dout) of the liquid crystal layer around the picture element region is smaller than the thickness (din) of the liquid crystal layer in the (opening) portion of the picture element region (din> d).
out), and 0.2 × din ≦ dout
It is preferable to satisfy the relationship of ≦ 0.8 × din. That is, when 0.2 × din> dout, the convex portion 3
6, the effect of weakening the interaction of the liquid crystal molecules between the pixel regions is not sufficient, and it may be difficult to form a single axially symmetric alignment region for each pixel region. Further, dout>
At 0.8 din, it may be difficult to inject the liquid crystal material into the liquid crystal cell.

The "picture element" is generally defined as a minimum unit for displaying. The term “picture element area” used in the specification of the present application refers to a partial area of the display device corresponding to “picture element”. However, in the case of a picture element having a large aspect ratio (long picture element), a plurality of picture element regions may be formed for one long picture element. The number of picture element regions formed corresponding to picture elements is as long as the axially symmetric orientation can be formed stably.
It is preferable that the number is as small as possible.

Here, the axially symmetric orientation refers to an orientation such as radial, concentric (tangential) or the like.

(Embodiment 1) FIG. 2 is a schematic diagram of a liquid crystal display device of Embodiment 1. 2A is a sectional view taken along line XX of FIG. 2B, and FIG. 2B is a plan view.

This liquid crystal display device has a pair of glass substrates 2 and 8, and a liquid crystal layer 16 is provided between them. On one (upper side of the figure) glass substrate 2, a transparent electrode 3 made of ITO and a vertical alignment layer 22 are formed with the former facing the substrate 2 side. A transparent electrode 10 made of ITO is formed on the other (lower side in the figure) glass substrate 8, and a convex portion 17 made of aluminum is formed on the transparent electrode 10. The protrusion 17 is provided so as to surround the picture element region 15 as shown in FIG. In addition, a vertical alignment layer 22 is formed on the outer surfaces of the transparent electrode 10 and the protrusion 17.

Further, a columnar spacer 20 is formed outside the picture element region between the transparent electrodes 10 (see FIG. 2B). The columnar spacer 20 adjusts the distance between the substrates 2 and 8 and is provided so as to reach the substrates 2 and 8. A vertical alignment layer 21 is also formed on the peripheral surface of the columnar spacer 20. I have.

The liquid crystal display device having such a configuration is manufactured as follows.

First, a transparent electrode 3 made of ITO and having a thickness of 700 nm is formed on one glass substrate 2.
JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated to form a vertical alignment layer 22.

Next, on the other glass substrate 8, a transparent electrode 10 made of ITO having a thickness of 700 nm and a width of 160 μm is formed in a stripe shape, and a convex portion 17 made of aluminum is formed on the transparent electrode 10. The projections 17 are formed by forming an aluminum thin film to a thickness of 3 μm and removing portions corresponding to the picture element regions 15 by photolithography and etching so as to leave regions of a width of 10 μm from both ends of the transparent electrode 10. went. Here, although aluminum was used as the metal thin film, the present invention is not limited to this, and chromium, nickel, molybdenum, titanium, copper, silver or gold alone or aluminum, chromium, nickel, Molybdenum, titanium,
Two or more alloys of copper, silver or gold may be used.

Next, using a photosensitive polyimide, a height of about 5 μm is formed outside the pixel region between the transparent electrodes 10.
m columnar spacers 20 were formed.

Next, JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated on the glass substrate 8 on which the transparent electrodes 10 and the projections 17 were formed, to form a vertical alignment layer 21.

Next, the two substrates 2 and 8 are bonded together, and an n-type liquid crystal material (Δε = −4.0, Δn = 0.08, cell gap 5
A twist angle unique to the liquid crystal material was set so as to be 90 ° twist in μm, thereby completing a liquid crystal cell. In the completed liquid crystal cell, the sheet resistivity of the transparent electrode 10 and the projection 17 as a two-layer structure electrode was 1.2 ohm / square.

Next, polarizing plates were arranged on both sides of the liquid crystal cell so as to be in a crossed Nicols state, thereby completing a liquid crystal display device.

FIG. 3 is a diagram showing the results of observing each picture element in a transmission mode using a polarizing microscope (crossed Nicols) while applying a voltage of about 4 V to the liquid crystal cell.

As can be understood from FIG. 3, during white display, the liquid crystal molecules in each picture element region are axially symmetrically aligned with respect to the axially symmetric alignment central axis over the entire liquid crystal panel.
In addition, it was observed that the axis axis of the axially symmetric alignment was formed substantially at the center of the picture element region, and a liquid crystal display device having excellent viewing angle characteristics without roughness or display unevenness was obtained.

(Embodiment 2) In this embodiment 2, the convex portion 1
A liquid crystal display device is formed in the same manner as in the first embodiment except that 7 is formed of a multilayer metal thin film.

First, a 700 nm thick transparent electrode 3 made of ITO is formed on one glass substrate 2.
ALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated to form a vertical alignment layer 22.

Next, a transparent electrode 10 made of ITO having a thickness of 700 nm and a width of 160 μm is formed in a stripe shape on the other glass substrate 8, and a projection 17 made of two layers of molybdenum and aluminum is formed on the transparent electrode 10. To form The formation of the projections 17 was performed as follows. For example, molybdenum is formed to a thickness of about 100 nm, aluminum is subsequently formed to a thickness of about 3 μm by vapor deposition, and a positive photoresist (TFRB-3; manufactured by Tokyo Ohka Co., Ltd.) is applied to a thickness of about 1 μm. develop. At this time, the presence of the molybdenum thin film between the aluminum thin film and the ITO (transparent electrode 10) can prevent the occurrence of pinholes in the ITO during development. continue,
The aluminum thin film and the molybdenum thin film are simultaneously etched away from the ends of the transparent electrode 10 so as to leave a region of 10 μm in width corresponding to the picture element region 15, and the photoresist 17 is peeled off to form the projection 17. Formed. Note that, here, aluminum and molybdenum were used as the metal thin film, but the present invention is not limited to this, and chromium, nickel, titanium, copper, silver, or gold alone may be used, or each of the multilayer metal thin films may be used. May be made of two or more alloys of aluminum, chromium, nickel, molybdenum, titanium, copper, silver or gold.

Next, using a photosensitive polyimide, a height of about 5 μm is formed outside the pixel region between the transparent electrodes 10.
m columnar spacers 20 were formed.

Next, JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated on the glass substrate 8 on which the transparent electrodes 10 and the projections 17 were formed, to form a vertical alignment layer 21.

Next, the two substrates 2 and 8 are bonded together, and an n-type liquid crystal material (Δε = −4.0, Δn = 0.08, cell gap 5
A twist angle unique to the liquid crystal material was set so as to be 90 ° twist in μm, thereby completing a liquid crystal cell. In the completed liquid crystal cell, the sheet resistivity of the transparent electrode 10 and the projection 17 as a two-layer structure electrode was 1.5 ohm / square.

Next, polarizing plates were arranged on both sides of the liquid crystal cell so as to be in a crossed Nicols state, and a liquid crystal display device was completed.

Each of the picture elements was observed in a transmission mode using a polarizing microscope (crossed Nicols) while applying a voltage of about 4 V to the completed liquid crystal cell.
At the time of white display, the liquid crystal molecules in each picture element region are oriented axially symmetrically around the axially symmetric alignment central axis over the entire liquid crystal panel, and the axially symmetric alignment central axis is substantially the same as the pixel region. It was observed that the liquid crystal display was formed at the central position, and a liquid crystal display device having excellent viewing angle characteristics without roughness or display unevenness could be obtained.

(Embodiment 3) In the third embodiment, the protrusion 1
A liquid crystal display device is formed in the same manner as in the first embodiment, except that 7 is formed of a multilayer film of a metal thin film and an organic resin layer as an insulating layer.

First, a 700 nm-thick transparent electrode 3 made of ITO is formed on one glass substrate 2.
ALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated to form a vertical alignment layer 22.

Next, a transparent electrode 10 made of ITO having a thickness of 700 nm and a width of 160 μm is formed in a stripe shape on the other glass substrate 8, and a conductive material made of aluminum is formed on the transparent electrode 10 as shown in FIG. A convex portion 17 composed of two layers of a region 17a and an insulating layer 17b composed of a resist is formed. The formation of the projections 17 was performed as follows. For example, aluminum is sputtered to a thickness of about 0.5
μm, and a positive photoresist (TFRB)
-3; manufactured by Tokyo Ohka Co., Ltd.) and then exposed and developed, and subsequently, an aluminum thin film was formed so as to leave a 20 μm wide area from both ends of the transparent electrode 10 in a pixel area. This was performed by removing the portion of the aluminum thin film corresponding to No. 15 by etching. Embodiment 3
Is a configuration in which a resist 17b is formed on an aluminum thin film 17a in the same area as the aluminum thin film 17a. Although aluminum was used as the metal thin film, the present invention is not limited to this, and chromium, nickel, molybdenum, titanium, copper,
A simple substance of silver or gold may be used, or an alloy of two or more of aluminum, chromium, nickel, molybdenum, titanium, copper, silver or gold may be used.

Next, using a photosensitive polyimide, a height of about 5 μm was formed outside the pixel region between the transparent electrodes 10.
m columnar spacers 20 were formed.

Next, JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated on the glass substrate 8 on which the transparent electrodes 10 and the projections 17 were formed, to form a vertical alignment layer 21.

Next, both substrates 2 and 8 are bonded together, and an n-type liquid crystal material (Δε = −4.0, Δn = 0.08, cell gap 5
A twist angle unique to the liquid crystal material was set so as to be 90 ° twist in μm, thereby completing a liquid crystal cell. In the completed liquid crystal cell, the sheet resistivity of the transparent electrode 10 and the projection 17 as a two-layer structure electrode was 1.4 ohm / square.

Next, polarizing plates were arranged on both sides of the liquid crystal cell so as to be in a crossed Nicols state, thereby completing a liquid crystal display device.

Each of the picture elements was observed in a transmission mode using a polarizing microscope (crossed Nicols) while applying a voltage of about 4 V to the completed liquid crystal cell.
At the time of white display, the liquid crystal molecules in each picture element region are oriented axially symmetrically around the axially symmetric alignment central axis over the entire liquid crystal panel, and the axially symmetric alignment central axis is substantially the same as the pixel region. It was observed that the liquid crystal display was formed at the central position, and a liquid crystal display device having excellent viewing angle characteristics without roughness or display unevenness could be obtained.

(Embodiment 4) In Embodiment 4, as in Embodiment 3, except that the convex portion 17 is formed of a multilayer film of a metal thin film and an organic resin layer as an insulating layer. A liquid crystal display device is formed in the same manner as in 1. However, in the above-described third embodiment, the insulating layer is formed on the metal thin film in the same area as the insulating layer. However, in the fourth embodiment, the insulating layer is formed so as to cover the upper surface and the side surface of the metal thin film. is there.

First, a 700 nm-thick transparent electrode 3 made of ITO is formed on one glass substrate 2.
ALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated to form a vertical alignment layer 22.

Next, a transparent electrode 10 of ITO having a thickness of 700 nm and a width of 160 μm is formed in a stripe shape on the other glass substrate 8, and a conductive material of aluminum is formed on the transparent electrode 10 as shown in FIG. A convex portion 17 composed of two layers of a region 17a and an insulating layer 17b composed of a resist is formed. The formation of the projections 17 was performed as follows. For example, the thickness of aluminum is about 1 μm by sputtering.
Formed, and a positive photoresist (TFRB-
3; manufactured by Tokyo Ohka Co., Ltd.)
Exposure and development. Subsequently, the portion of the aluminum thin film corresponding to the picture element region 15 is removed by etching so that the aluminum thin film remains in a region having a width of 10 μm from both ends of the transparent electrode 10. Thereafter, the photoresist is baked at about 120 ° C. Then, the photoresist existing only on the aluminum thin film was softened, and the upper surface and the side surfaces of the aluminum thin film 17a were covered with the photoresist 17b, thereby forming the projections 17. Although aluminum was used as the metal thin film, the present invention is not limited to this, and chromium, nickel, molybdenum, titanium, copper, silver or gold alone or aluminum, chromium, nickel, molybdenum, titanium, copper , Silver or gold may be used.

Next, using a photosensitive polyimide, a height of about 5 μm was formed outside the pixel region between the transparent electrodes 10.
m columnar spacers 20 were formed.

Next, JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated on the glass substrate 8 on which the transparent electrodes 10 and the projections 17 were formed, to form a vertical alignment layer 21.

Next, the two substrates 2 and 8 are bonded together, and an n-type liquid crystal material (Δε = −4.0, Δn = 0.08, cell gap 5
A twist angle unique to the liquid crystal material was set so as to be 90 ° twist in μm, thereby completing a liquid crystal cell. In the completed liquid crystal cell, the sheet resistivity of the transparent electrode 10 and the convex portion 17 as a two-layer structure electrode was 1.6 ohm / square.

Next, a polarizing plate was arranged on both sides of the liquid crystal cell so as to be in a crossed Nicols state, thereby completing a liquid crystal display device.

Each of the picture elements was observed in a transmission mode using a polarizing microscope (crossed Nicols) while applying a voltage of about 4 V to the completed liquid crystal cell.
At the time of white display, the liquid crystal molecules in each picture element region are oriented axially symmetrically around the axially symmetric alignment central axis over the entire liquid crystal panel, and the axially symmetric alignment central axis is substantially the same as the pixel region. It was observed that the liquid crystal display was formed at the central position, and a liquid crystal display device having excellent viewing angle characteristics without roughness or display unevenness could be obtained.

In the above-described second to fourth embodiments, the metal thin film has two layers, or the metal thin film and an organic resin layer (eg, a resist) have two layers. However, the present invention is not limited to this. Needless to say, a multilayer structure of three or more layers having more than two layers with the same material configuration may be used. In addition, this is the same as Embodiment 5 to be described later, Embodiments 2 to
The same applies to the case where the fourth embodiment is applied.

(Embodiment 5) Embodiment 5 is a case where the present invention is applied to a plasma address type liquid crystal display device.

FIG. 6 is a schematic sectional view showing a specific structure of the plasma addressed liquid crystal display device according to the present embodiment.

This liquid crystal display device has a substrate 58 made of transparent glass or the like on one side (upper side in the figure) with a liquid crystal layer 59 interposed therebetween.
And a plasma generating substrate 52 on the other side (lower side in the figure) of which a thin glass 53 as a dielectric sheet and a substrate 54 are arranged to face each other. Between the substrate 54 of the plasma substrate 52 and the thin glass 53, a partition wall 57 is formed in a line shape, and a space surrounded by the partition 57, the substrate 54, and the thin glass 53 is filled with an ionizing gas. The thus-formed linear channel 55 is constituted. In each channel 55, an anode electrode A and a cathode electrode K for ionizing the ionizing gas are provided.

On the other hand, a color filter 63 is provided on the liquid crystal layer 59 side of the substrate 58, and a transparent electrode 60 as a data line is formed on the color filter 63 with respect to a striped and linear channel 55. , And are wired, for example, in the vertical direction. The liquid crystal layer 59 is sandwiched between the substrate 58 and the thin glass 53, and the cell thickness between the substrate 58 and the thin glass 53 is kept constant by the column spacer 67. The substrate 58 and the thin glass 53
A vertical alignment film 68 is formed on the surface on the liquid crystal layer 59 side. Further, a portion including the substrate 58, the color filter 63, the transparent electrode 60, and the liquid crystal layer 59 constitutes a display cell 51.

A polarizing plate 69a is provided on one side (upper side in the figure) of the liquid crystal display device thus configured, and a polarizing plate 69b and a backlight 62 are provided on the other side (lower side in the figure).

In the method of manufacturing the plasma addressed liquid crystal display device, a plasma generating substrate 52 shown in FIG. 6 is used instead of the glass substrate 8 shown in FIG. The plasma generating substrate 52 is manufactured by a known method.

FIG. 7 is a detailed schematic diagram of the display cell 51 of the plasma addressed liquid crystal display device of the second embodiment. FIG. 7A is a cross-sectional view taken along line XX of FIG.
FIG. 7B shows a plan view.

[0098] A JALS-
204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated to form a vertical alignment layer 68.

A color filter 63 is formed on a glass substrate 58 on the upper side of FIG.
A transparent electrode 60 having a thickness of 00 nm and a width of 160 μm is formed in a stripe shape, and a projection 70 made of aluminum is formed on the transparent electrode 60. The projections 70 are formed by forming an aluminum thin film to a thickness of 3 μm and removing portions corresponding to the picture element regions 71 by photolithography and etching so as to leave regions with a width of 10 nm from both ends of the transparent electrode 60. went. Further, a columnar spacer 67 having a height of about 5 μm was formed using a photosensitive polyimide outside the pixel region between the transparent electrodes 60. Further, JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) is formed on the glass substrate 58 on which the transparent electrode 60 and the projection 70 are formed.
Was spin-coated to form a vertical alignment layer 68. In this embodiment, not only aluminum but also the above-described metal simple substance or alloy can be used.

Then, the thin glass 53 on the side of the plasma generating substrate 52 and the glass substrate 58 on the side of the display cell 51 are bonded together, and a liquid crystal layer 59 is formed between the thin glass 53 and the glass substrate 58 as an n-type liquid crystal material. (Δε = −4.0,
Δn = 0.08, and a twist angle unique to the liquid crystal material is set so as to be 90 ° twist at a cell gap of 5 μm). Note that the sheet resistivity of the transparent electrode 60 and the projection 70 as a two-layer structure electrode was 1.2 ohm / square.

Thereafter, on both sides of the bonded plasma generating substrate 52 and the display cell 51, polarizing plates 69a and 69b are arranged in a crossed Nicols state as shown in FIG. Backlight 6 outside
2 to complete the plasma addressed liquid crystal display device.

When this plasma-addressed liquid crystal display device was set to a display state and each picture element was observed in a transmission mode using a polarizing microscope (crossed Nicols), the same results as in FIG. 3 were obtained.

As can be understood from the above, at the time of white display, the liquid crystal molecules in each picture element region are axially symmetrically aligned around the axially symmetric alignment central axis over the entire panel.
In addition, it is observed that the axially symmetric alignment central axis is formed almost at the center of the picture element region, and it is possible to obtain a plasma-addressed liquid crystal display device having excellent viewing angle characteristics without roughness or display unevenness. Was.

Comparative Example 1 FIG. 9 is a sectional view of a liquid crystal display device used in the conventional example.

This liquid crystal display device is manufactured as follows. That is, a 700-nm-thick transparent electrode 104 made of ITO was formed on one glass substrate 102, and JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated to form a vertical alignment layer 105.

A transparent electrode 103 made of ITO and having a thickness of 700 nm is formed on the other glass substrate 101, and a spacer having a height of about 5 μm is formed outside the pixel region on the transparent electrode 103 by using photosensitive polyimide. 107 was formed. After that, use an acrylic negative resist with a height of about 3μ.
m convex portions 106 were formed. The size of the area surrounded by the convex portion 106, that is, the size of the picture element area is 190 μm × 325.
μm. JALS-204 (manufactured by Nippon Synthetic Rubber Co., Ltd.) was spin-coated thereon to form a vertical alignment layer 105.

Thereafter, both substrates are bonded together, and an n-type liquid crystal material (Δε =
−4.0, Δn = 0.08, 90 at cell gap 5 μm
The liquid crystal cell was completed by injecting a twist angle specific to the liquid crystal material so as to obtain a twist. The sheet resistivity of the transparent electrode 103 was 6.0 ohm / square.

Thereafter, polarizing plates were arranged on both sides of the liquid crystal cell so as to be in a crossed Nicols state, thereby completing a liquid crystal display device.

FIG. 8 shows the results of observing each picture element in a transmission mode using a polarizing microscope (crossed Nicols) while applying a voltage of about 4 V to the completed liquid crystal cell.

As can be understood from FIG. 8, at the time of white display, the liquid crystal molecules in each picture element region are axially symmetric with respect to the central axis. It was observed that the central axis was formed at a position largely deviated from the center of the picture element region, and a liquid crystal display device with excellent viewing angle characteristics without roughness or display unevenness could not be obtained.

Although the fifth embodiment has a configuration in which the first embodiment is applied to the plasma-addressed liquid crystal display device, the present invention is not limited to this, and the second embodiment described above is applied to the plasma-addressed liquid crystal display device. Embodiment 4 can be applied. In the plasma-addressed liquid crystal display device obtained in this case as well, the liquid crystal molecules in each pixel region are axially symmetrically aligned around the axially symmetric alignment central axis, and the axially symmetrical liquid crystal display device is obtained. It is observed that the shape-oriented central axis is formed substantially at the center of the picture element region, and it is a matter of course that the viewing angle characteristic is excellent without roughness and display unevenness.

[0112]

As described above in detail, in the present invention, the position and size of the picture element region of the liquid crystal layer are defined by the presence of the convex portion substantially surrounding the picture element region, The liquid crystal molecules in the pixel region are axially symmetrically aligned around the central axis, and the conductive region of the convex portion is formed so as to be in contact with the transparent electrode. The active region functions as an auxiliary electrode of the transparent electrode, and as a result, the resistance of the electrode can be reduced, thereby causing non-uniformity of the operating voltage and the applied voltage when the axially symmetric alignment fixed layer is formed in the liquid crystal panel. Therefore, a uniform and stable axially symmetric alignment state can be realized in the liquid crystal panel, and the display quality of the liquid crystal display device can be improved.

Further, by forming the conductive region of the convex portion with a metal thin film, the convex portion can be accurately formed by inexpensive wet etching. Further, when the conductive region of the convex portion is formed of a multi-layered metal thin film, it is possible to prevent the occurrence of an electrolytic corrosion reaction, and it is possible to pattern the conductive region of the convex portion with a positive resist. Processing becomes possible, and high definition of the liquid crystal display device can be realized.

In the case where the convex portion has a multilayer structure in which an insulating layer is laminated on a conductive region, the adhesiveness with an alignment film formed on the convex portion can be improved. Vertical leakage with the transparent electrode formed on the other substrate can be prevented. In addition, a photoresist used for patterning and forming a conductive region can be used as an insulating layer without etching, and then used without being peeled off, so that the process can be simplified. In the case where the upper surface and the side surface of the conductive region of the convex portion are covered with the insulating layer, it is possible to prevent the disorder of the alignment of the liquid crystal molecules due to the lateral electric field generated between the conductive regions of the adjacent convex portion.

Further, according to the present invention, there is provided a high contrast liquid crystal display device having excellent viewing angle characteristics in which liquid crystal molecules in each picture element region are oriented in an axially symmetric manner. The obtained liquid crystal display device of the present invention is particularly suitably used for a large-sized liquid crystal display device suitable for application to a high-definition television such as an HDTV, a CAD display, and the like.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams for explaining a basic configuration of a liquid crystal display device according to the present invention, wherein FIGS. ) Shows the state when an axially symmetric alignment centering voltage is applied, (a) and (c) are cross-sectional views, and (b) and (d) show the results obtained by observing the top surface with a crossed Nicol state polarizing microscope. .

FIGS. 2A and 2B are diagrams illustrating a liquid crystal display device according to a first embodiment of the present invention, wherein FIG. 2A is a cross-sectional view and FIG.

FIG. 3 is a diagram for explaining a relationship between a position of an axially symmetric alignment central axis and display quality in the first and second embodiments of the present invention.

FIG. 4 is a cross-sectional view illustrating a structure of a protrusion according to a third embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating a structure of a protrusion according to a fourth embodiment of the present invention.

FIG. 6 is a sectional view illustrating a plasma addressed liquid crystal display device according to a second embodiment of the present invention.

7A and 7B are diagrams showing a display cell portion of a plasma addressed liquid crystal display device according to a second embodiment of the present invention, wherein FIG. 7A is a sectional view and FIG. 7B is a plan view.

FIG. 8 is a diagram for explaining the relationship between the position of the axially symmetric alignment central axis and the display quality in the comparative example.

9A and 9B show a conventional liquid crystal display device, wherein FIG. 9A is a cross-sectional view and FIG. 9B is a plan view.

FIGS. 10A and 10B are diagrams for explaining the configuration and operation principle of another conventional liquid crystal display device. FIGS. 10A and 10B are diagrams illustrating a state in which no axial centering voltage is applied to an axially symmetric alignment, and FIGS. ) Shows the state when an axially symmetric alignment centering voltage is applied, (a) and (c) are cross-sectional views, and (b) and (d) show the results obtained by observing the top surface with a crossed Nicol state polarizing microscope. .

FIG. 11 is a diagram showing a voltage transmittance curve of the liquid crystal display device.

[Explanation of symbols]

 Reference Signs List 2 glass substrate 3 transparent electrode 8 glass substrate 10 transparent electrode 15 picture element region 16 liquid crystal layer 17 convex portion 17a conductive region 17b insulating layer 20 columnar spacer 21 vertical alignment layer 22 vertical alignment layer 31 transparent electrode 32 substrate 33 transparent electrode 34 substrate 36 convex portion 38a, 38b vertical alignment layer 40 liquid crystal layer 42 liquid crystal molecule 44 axis-symmetric alignment central axis 51 display cell 52 plasma generation substrate 53 thin glass 54 substrate 55 channel 57 partition wall 58 substrate 59 liquid crystal layer 60 transparent electrode A anode electrode K Cathode electrode 62 Backlight 63 Color filter 67 Columnar spacer 68 Vertical alignment layer 69a, 69b Polarizer 70 Convex part 71 Pixel region

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Noriaki Nakamura 22-22 Nagaikecho, Abeno-ku, Osaka City, Osaka Inside Sharp Corporation (72) Inventor Katsuyuki Himejima 22-22 Nagaikecho, Abeno-ku, Osaka City, Osaka Inside the corporation

Claims (11)

[Claims] 1. A liquid crystal display device comprising: a pair of substrates; and a liquid crystal layer sandwiched between the pair of substrates. A transparent electrode is formed on the pair of substrates. The liquid crystal layer includes at least one picture element for each picture element. A liquid crystal display device having a pixel region, wherein liquid crystal molecules in the pixel region are aligned in an axially symmetric manner with respect to an axially symmetric alignment central axis. A convex portion substantially surrounding the picture element territory is formed, and the convex portion has a region made of a conductive material, and the conductive region is A liquid crystal display device being in contact with a transparent electrode. 2. The liquid crystal molecules of the liquid crystal layer have a negative dielectric anisotropy. When no voltage is applied, the liquid crystal molecules are oriented substantially perpendicular to the pair of substrates. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is aligned in an axially symmetric manner about an axially symmetric alignment central axis for each of a plurality of picture element regions. 3. The liquid crystal display device according to claim 1, wherein a transparent electrode formed on at least one of the pair of substrates has a stripe shape. 4. The liquid crystal display device according to claim 1, wherein the conductive region of the projection is formed of a single-layer metal thin film or a multilayer metal thin film. 5. The liquid crystal according to claim 1, wherein said convex portion comprises a conductive region and an insulating layer, and said insulating layer is laminated on said conductive region. Display device. 6. The method according to claim 1, wherein the convex portion comprises a conductive region and an insulating layer, and the insulating layer is formed so as to cover the conductive region. Liquid crystal display. 7. The liquid crystal according to claim 4, wherein the metal thin film is made of a simple substance of aluminum, chromium, nickel, molybdenum, titanium, copper, silver or gold, or an alloy of two or more thereof. Display device. 8. The liquid crystal display device according to claim 1, wherein the width of the projection is 5 μm or more and 20 μm or less. 9. The liquid crystal display device according to claim 1, wherein the height of the projection is 20% or more and 80% or less of the thickness of the liquid crystal layer. 10. The liquid crystal display device according to claim 1, wherein the thickness of the transparent electrode is in a range of 700 Å to 4000 Å. 11. The sheet resistivity of the projection is 0.5 ohm /.
The liquid crystal display device according to any one of claims 1 to 4, wherein the range is from □ to 2.0 ohm / □.