JP2009192867A - Liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an auxiliary capacitance without deteriorating an aperture ratio in a liquid crystal display device adapted to control the orientation of liquid crystal molecules using a substantially horizontal electric field to a transparent substrate. <P>SOLUTION: Liquid crystal molecules M with negative dielectric anisotropy Δε are held between a first transparent substrate 10 and a second transparent substrate 20. In each pixel 1P, respective linear parts of a common electrode 17 and a pixel electrode 18 formed of transparent conductive materials are alternately arranged on the first transparent substrate 10. A capacitive electrode 22 formed of a transparent conductive material and including a plurality of linear parts extending oppositely to the pixel electrode 18 and a slit part 22S extending between them is disposed on the second transparent substrate 20. A potential SC equal to a common potential COM applied to the common electrode 17 is applied to the capacitive electrode 22 by a voltage application means 103 connected thereto. The auxiliary capacitance Cs of each pixel 1P is constituted by the pixel electrode 18, a liquid crystal layer LC, and the capacitive electrode 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device that controls the alignment of liquid crystal molecules using an electric field in a substantially horizontal direction with respect to a transparent substrate.

As a liquid crystal display device capable of obtaining a high contrast and a wide viewing angle, a liquid crystal display device that controls the alignment of liquid crystal molecules using an electric field in a substantially horizontal direction with respect to two transparent substrates sandwiching the liquid crystal, for example, IPS (In- 2. Description of the Related Art Liquid crystal display devices that operate in a plain switching (FSP) mode, an FFS (Fringe-Field Switching) mode, and the like are known. In this liquid crystal display device, a pixel electrode to which a display signal is applied and a common electrode to which a common potential is applied are arranged on one transparent substrate.

An example of an IPS mode liquid crystal display device will be described with reference to the drawings. FIG. 9 is a cross-sectional view showing a conventional IPS mode liquid crystal display device. For convenience of explanation, only one pixel 2P is shown among a plurality of pixels arranged in the display area.

A liquid crystal layer LC is sandwiched between a first transparent substrate 10 and a second transparent substrate 20 made of a glass substrate or the like. The first transparent substrate 10 faces the light source BL. The first polarizing plate 11 is disposed on the side of the first transparent substrate 10 facing the light source BL, and the first semiconductor layer 12A made of polysilicon or the like and the second side are not facing the light source BL. The semiconductor layer 12B is disposed. The first semiconductor layer 12A is an active layer of the pixel transistor TR, and the second semiconductor layer 12B is a capacitor electrode constituting the auxiliary capacitor 10C connected to the pixel transistor TR.
The first semiconductor layer 12 </ b> A and the second semiconductor layer 12 </ b> B are covered with the gate insulating film 13. A part of the pixel selection signal line GL extends as a gate electrode on the gate insulating film 13 overlapping with the first semiconductor layer 12A. On the gate insulating film 13 overlapping the second semiconductor layer 12B,
An auxiliary capacitance line SL extends as another capacitance electrode constituting the auxiliary capacitance 10C. Here, the gate insulating film 13 covering the second semiconductor layer 12B functions as a capacitor insulating film of the auxiliary capacitor 10C.

The gate insulating film 13, the pixel selection signal line GL, and the auxiliary capacitance line SL are covered with the interlayer insulating film 14. Display signal lines DL and electrodes 15 are arranged on the interlayer insulating film 14. The display signal line DL is connected to the drain region 1 of the first semiconductor layer 12A through the contact hole CH1.
Connected to 2D. The electrode 15 is connected to the first semiconductor layer 1 through the contact hole CH2.
It is connected to the source region 12S of 2A and is connected to the second semiconductor layer 12B through the contact hole CH3. These are covered with a flattening film 16, and a common electrode 17 made of a transparent conductive material such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide) is disposed on the flattening film 16. Has been. The common electrode 17 extends as a plurality of linear portions in a region contributing to display, and the linear portions are connected to each other in other regions (not shown).

Between the linear portions of each common electrode 17, pixel electrodes 18 made of a transparent conductive material such as ITO or IZO, to which a display signal is applied, are arranged at a predetermined distance. Pixel electrode 1
8 extends as a plurality of linear portions in the region between the common electrodes 17, and the linear portions are connected to each other in other regions (not shown). The pixel electrode 18 is connected to the electrode 15 through the contact hole CH4. The common electrode 17 and the pixel electrode 18 are covered with a first alignment film 19.

On the other hand, a second polarizing plate 21 having a transmission axis perpendicular to the first polarizing plate 11 is disposed on the second transparent substrate 20 on the side not facing the liquid crystal layer LC. A black matrix (not shown) and a color filter (not shown) are arranged on the second transparent substrate 20 on the side facing the liquid crystal layer LC. These are covered with a second alignment film 25 having a rubbing direction parallel to the rubbing direction of the first alignment film 11.

Liquid crystal molecules M of the liquid crystal layer LC sandwiched between the first transparent substrate 10 and the second transparent substrate 20
Is initially aligned according to the rubbing direction of the alignment films 19 and 25. When a display signal is applied to the pixel electrode 18, an electric field (hereinafter referred to as a horizontal electric field component) extending in a substantially horizontal direction with respect to the first transparent substrate 10 between the common electrode 17 and the pixel electrode 18. Accordingly, the alignment direction of the liquid crystal molecules M of the liquid crystal layer LC is controlled. Optical control is performed through the liquid crystal layer LC, and white display or black display is performed. At this time, the display signal is held for a certain period by the auxiliary capacitor 10C.

A liquid crystal display device that controls the alignment of liquid crystal molecules using an electric field in a substantially horizontal direction with respect to a transparent substrate is described in Patent Document 1.
JP 2007-232785 A

However, in the liquid crystal display device described above, the storage capacitor line SL made of a colored metal material such as chromium (Cr) or molybdenum (Mo) is used as the capacitor electrode constituting the storage capacitor 10C.
Must be formed on the first transparent substrate 10 in the pixel 2P. Since the area where the auxiliary capacitance line SL is formed does not contribute to display, there is a problem that the aperture ratio of the pixel 2P is lowered.
Further, the manufacturing process for the auxiliary capacitor 10C is complicated, and the reduction in manufacturing cost is hindered.

The liquid crystal display device of the present invention has been made in view of the above problems, and includes a plurality of pixels.
Each pixel includes a liquid crystal layer sandwiched between a first substrate and a second substrate, a common electrode disposed on the first substrate and applied with a common potential, and a common electrode on the first substrate. Pixel electrodes to which display signals are applied alternately and linear portions that are arranged on the second substrate and extend to face at least one pixel electrode have openings in regions that do not overlap with the pixel electrodes And a counter electrode.

In the liquid crystal display device of the present invention having the above structure, the liquid crystal layer has negative dielectric anisotropy.

Further, the liquid crystal display device of the present invention has the above-described structure, wherein the counter electrode includes a plurality of linear portions extending facing the plurality of pixel electrodes, a plurality of slit portions that open areas that do not overlap each pixel electrode, It is characterized by having.

The liquid crystal display device according to the present invention is characterized in that, in the above structure, the counter electrode forms an auxiliary capacitor together with the pixel electrode and the liquid crystal layer.

In the liquid crystal display device of the present invention having the above structure, the counter electrode is formed of a light-shielding conductive material that covers the boundary of each pixel, and at least faces the pixel electrode arranged at the end of each pixel. It is characterized by extending.

Further, the liquid crystal display device of the present invention has the above-described structure, wherein the counter electrode includes a plurality of linear portions extending facing the plurality of pixel electrodes, a plurality of slit portions that open areas that do not overlap each pixel electrode, It has a conductive light-shielding portion that covers the boundary of each pixel and extends at least facing the pixel electrode disposed at the end of each pixel.

In the liquid crystal display device of the present invention, in the above structure, the linear portion is made of a conductive translucent material, the light shielding portion is made of a material having a lower resistance than the linear portion, and the linear portion and the light shielding portion. Are electrically connected.

In the liquid crystal display device of the present invention having the above structure, a common potential is applied to the counter electrode.

According to such a configuration, the auxiliary capacitance can be provided without reducing the aperture ratio by the pixel electrode on the first substrate, the counter electrode on the second substrate, and the liquid crystal layer sandwiched therebetween. In addition, it is possible to simplify the manufacturing process for the auxiliary capacity.

According to the present invention, in a liquid crystal display device that controls the alignment of liquid crystal molecules using an electric field in a substantially horizontal direction with respect to a transparent substrate, an auxiliary capacitor can be provided without reducing the aperture ratio.

[First Embodiment]
A liquid crystal display device according to a first embodiment of the present invention will be described. First, a schematic equivalent circuit of the liquid crystal display device will be described with reference to the drawings. FIG. 1 is an equivalent circuit diagram of the liquid crystal display device according to the present embodiment. In FIG. 1, among the plurality of pixels 1P included in the liquid crystal display device,
Only a part is shown.

As shown in FIG. 1, each pixel corresponds to each intersection of a plurality of pixel selection signal lines GL to which a pixel selection signal is applied from the vertical drive circuit 101 and a display signal line DL to which a display signal is applied from the horizontal drive circuit 102. Thus, the pixel 1P is arranged. Each pixel 1P has a gate serving as a pixel selection signal line G.
A pixel transistor TR such as a thin film transistor having a drain connected to L and a drain connected to the display signal line DL is disposed. A pixel electrode (not shown) is connected to the source of the pixel transistor TR, and an electric field is formed in the liquid crystal layer LC by a display signal applied to the pixel electrode and a common potential COM applied to the common electrode (not shown). The Further, an auxiliary capacitor Cs that holds a display signal applied to the pixel electrode is connected between the pixel electrode and a capacitor electrode (not shown) to which the potential SC is applied. The other capacitor Cp will be described later in the description of the operation of the liquid crystal display device.

Hereinafter, a detailed configuration of the liquid crystal display device will be described with reference to the drawings. 2 and 3 are plan views showing the liquid crystal display device according to the present embodiment. FIG. 2 shows a configuration on the first transparent substrate 10 side, and FIG. 3 shows a configuration on the second transparent substrate 20 side. ing. FIGS. 2 and 3 show regions corresponding to four adjacent pixels 1P among the plurality of pixels 1P, and show only main components. 4 is a cross-sectional view taken along line XX in FIGS. 2 and 3, and FIG.
FIG. 4A shows an off state in which no voltage is applied to the pixel electrode 18 to be described later, and FIG. 4B shows an on state in which a voltage is applied to the pixel electrode 18. In FIG. 4 (A) and FIG. 4 (B),
Only one pixel 1P is shown from among the plurality of pixels 1P. 2, 3, and 4, the same components as those shown in FIGS. 1 and 9 are referred to with the same reference numerals.

As shown in FIGS. 2 and 4A, a liquid crystal layer LC having a negative dielectric anisotropy Δε between a first transparent substrate 10 and a second transparent substrate 20 made of a glass substrate or the like. Is pinched. A first polarizing plate 11 is disposed on the side of the first transparent substrate 10 facing the light source BL. On the side of the first transparent substrate 10 not facing the light source BL, a pixel transistor TR similar to that shown in FIG. 9 is arranged. However, the auxiliary capacitor 10C shown in FIG. 9 is not arranged. The pixel transistor TR is covered with the planarizing film 16. Here, for convenience of explanation, the illustration of the pixel transistor TR is omitted, and the configuration from the first transparent substrate 10 to the planarizing film 16 is omitted as the same layer.

On the planarizing film 16, ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxid) is used.
A common electrode 17 made of a transparent conductive material such as e) is disposed. A voltage application unit 103 is connected to the common electrode 17, and a common potential COM is applied from the voltage application unit 103. The voltage application means 103 is a voltage generation circuit that outputs a predetermined voltage, or a voltage application terminal to which a predetermined voltage is applied from the outside. The common electrode 17 extends as a plurality of linear portions in a region contributing to display, and in other regions, that is, regions not contributing to display,
Each linear part is mutually connected.

Between the linear portions of each common electrode 17, pixel electrodes 18 made of a transparent conductive material such as ITO or IZO, to which a display signal is applied, are arranged at a predetermined distance. Pixel electrode 1
8 extends as a plurality of linear portions in the region between the common electrodes 17, and in other regions, that is, regions that do not contribute to display, the linear portions are connected to each other. Although not shown here, the pixel electrode 18 is electrically connected to the source region 12D of the pixel transistor TR through a contact hole or the like. Preferably, the width D1 of the linear portion of the common electrode 17 is the same as the width D2 of the linear portion of the pixel electrode 18 and is about 4 μm. Preferably, the distance D3 between the linear portion of the common electrode 17 and the linear portion of the pixel electrode 18 is about 2 μm. These widths D1, D2, and D3 may be values other than those described above.

The common electrode 17 and the pixel electrode 18 are covered with a first alignment film 19. First alignment film 19
The rubbing direction is parallel to the transmission axis of the first polarizing plate 11. Further, the angle θ formed by the rubbing direction of the first alignment film 19 and the longitudinal direction of the linear portion of the pixel electrode 18 is about 45 ° to about 90 °, preferably about 87 °.

On the other hand, a second polarizing plate 21 having a transmission axis perpendicular to the first polarizing plate 11 is disposed on the second transparent substrate 20 on the side not facing the liquid crystal layer LC. Although not shown, a black matrix and a color filter are arranged on the side corresponding to the liquid crystal layer LC on the second transparent substrate 20.

On the color filter, a capacitive electrode 22 (that is, an example of the counter electrode of the present invention) made of a transparent conductive material such as ITO or IZO as shown in FIG. 3 is disposed. The capacitive electrode 22
In the region contributing to the display, a plurality of linear portions are formed so as to extend opposite to the respective linear portions of the pixel electrode 18, and in the other regions, that is, the regions that do not contribute to the display, each linear shape of the capacitor electrode 22. The parts are connected to each other. The width D4 of the linear portion of the capacitor electrode 22 is the same as the width D2 of the linear portion of the pixel electrode 18 unless an error due to accuracy in the manufacturing process is taken into consideration.

A plurality of slit portions 22 </ b> S are provided between the linear portions of the capacitive electrode 22.

If the capacitor electrode 22 is not provided with the slit portion 22S, the refractive index of the transparent conductive material constituting the capacitor electrode 22 and the refractive index of the liquid crystal layer LC are different.
The light and external light are reflected, and the transmittance and contrast are lowered in the entire region contributing to display. On the other hand, in the present embodiment, as described above, the capacitive electrode 22 is provided with the plurality of slit portions 22S, and therefore, in the region opened by the slit portion 22S, the refractive index of the capacitive electrode 22 and the refractive index of the liquid crystal layer LC. There is no reduction in transmittance and contrast due to the difference.

Further, a voltage application unit 103 is connected to the capacitor electrode 22, and a potential SC is applied from the voltage application unit 103. The potential SC is a common potential CO applied to the common electrode 17.
It is preferably the same potential as M. By making the potential SC the same as the common potential COM, an unnecessary capacitance Cp as shown in FIG. 1 is less likely to occur between the common electrode 17 and the capacitance electrode 22, and an unnecessary change in orientation in the liquid crystal layer LC. This is because no longer occurs.

The capacitor electrode 22 is a second electrode having a rubbing direction parallel to the rubbing direction of the first alignment film 11.
The alignment film 25 is covered.

Since the liquid crystal molecules M of the liquid crystal layer LC sandwiched between the first transparent substrate 10 and the second transparent substrate 20 described above have a negative dielectric anisotropy Δε, the major axis direction thereof is Rotate to be orthogonal to the direction of the electric field. The negative dielectric anisotropy Δε is about −3.0 to about −10.0, preferably about −5.0.

In this liquid crystal display device, the auxiliary capacitor Cs of each pixel 1P is configured with the pixel electrode 18 as a first capacitor electrode, the liquid crystal layer LC as a capacitor insulating layer, and the capacitor electrode 22 as a second capacitor electrode.
That is, unlike the conventional auxiliary capacitor 10C, it is not necessary to arrange the auxiliary capacitor line SL made of a colored metal material such as chromium on the first transparent substrate 10 in the pixel 1P as the capacitor electrode. Further, it is not necessary to dispose the second semiconductor layer 12B overlapping the storage capacitor line SL. Accordingly, the auxiliary capacitance Cs can be provided without reducing the display area by the arrangement of the auxiliary capacitance line SL and the second semiconductor layer 12B overlapping therewith, that is, without reducing the aperture ratio of the pixel 1P. . Further, since the manufacturing process for the auxiliary capacitor Cs is simplified, the manufacturing cost can be reduced.

In order to obtain an auxiliary capacitance Cs having a sufficient capacitance value, the cell gap is about 2.0 μm, for example.
Corresponding to this, the birefringence Δn of the liquid crystal layer LC is preferably about 0.15, for example.

The operation of the above-described liquid crystal display device will be described below. As shown in FIG. 4A, in an off state in which no voltage is applied to the pixel electrode 18, the liquid crystal molecules M of the liquid crystal layer LC are homogeneously aligned substantially horizontally with respect to the first transparent substrate 10. Further, in the plane horizontal to the first transparent substrate 10, the major axis direction of the liquid crystal molecules M is parallel to the transmission axis of the first polarizing plate 11.

Here, regardless of whether or not a voltage is applied to the pixel electrode 18 to the capacitor electrode 22,
A potential SC is applied. When the potential SC is the same as the common potential COM, the liquid crystal layer LC
Since no electric field is generated or hardly generated, the major axis direction of the liquid crystal molecules does not change. When the potential SC is different from the common potential COM, an electric field substantially perpendicular to the first transparent substrate 10 is generated between the common electrode 17 and the capacitor electrode 22, and an unnecessary capacitor Cp as shown in FIG. 1 is generated. Although it becomes easy, since the dielectric anisotropy Δε of the liquid crystal molecules M is negative, the major axis direction of the liquid crystal molecules M is the first in accordance with the electric field in the direction substantially perpendicular to the first transparent substrate 10. The transparent substrate 10 is surely oriented horizontally.

In this OFF state, the light of the light source BL linearly polarized by the first polarizing plate 11 passes through the liquid crystal layer LC with the polarization axis as it is and enters the second polarizing plate 21. However, this light is absorbed by the second polarizing plate 21 because its polarization axis is orthogonal to the transmission axis of the second polarizing plate 21. That is, black display (normally black) is obtained.

On the other hand, as shown in FIG. 4B, when the voltage is applied to the pixel electrode 18, the first transparent substrate 10 is interposed between the common electrode 17 and the pixel electrode 18 in accordance with the display signal. Thus, a substantially horizontal electric field, that is, a horizontal electric field component is generated. In addition, since the potential SC is applied to the capacitor electrode 22, an electric field is also generated between the pixel electrode 18 and the capacitor electrode 22. Therefore, the liquid crystal layer L
In C, a substantially horizontal electric field, that is, a horizontal electric field component is generated with respect to the first transparent substrate 10, and a substantially vertical electric field, that is, a vertical electric field component is generated.

Since the dielectric anisotropy Δε of the liquid crystal molecules M is negative, the major axis direction of the liquid crystal molecules M is reliably aligned horizontally with respect to the first transparent substrate 10 according to the vertical electric field component. At the same time, it rotates in a plane parallel to the first transparent substrate 10 in accordance with the horizontal electric field component. At the same time, the vertical electric field component is held for a certain period by the auxiliary capacitor Cs including the pixel electrode 18, the liquid crystal layer LC, and the capacitor electrode 22.

In this ON state, the light of the light source BL linearly polarized by the first polarizing plate 11 becomes elliptically polarized light due to birefringence in the liquid crystal layer LC and enters the second polarizing plate 21. Among the elliptically polarized light, a component that coincides with the transmission axis of the second polarizing plate 21 is emitted and white display is performed. that time,
Since the electric field generated between the pixel electrode 18 and the capacitor electrode 22, that is, the vertical electric field component, the liquid crystal molecules M are prevented from tilting in a substantially vertical direction with respect to the first transparent substrate 10. The white display can be realized.

Further, in the black display and the white display described above, the refractive index of the transparent conductive material constituting the capacitor electrode 22 and the refractive index of the liquid crystal layer LC in the plurality of slit portions 22S provided in the capacitor electrode 22 constituting the auxiliary capacitor Cs. The transmittance and contrast are not reduced due to the difference between the two. for that reason,
Compared with the case where the entire region contributing to the display of the pixel 1P is covered with the capacitor electrode 22, the transmittance and contrast can be increased, and the display quality can be improved.
[Second Embodiment]
The liquid crystal display device according to the second embodiment of the present invention will be described below. FIG. 5 is a plan view showing the liquid crystal display device according to the present embodiment, and shows the configuration of the second transparent substrate 20 side. FIG. 5 shows a region corresponding to four adjacent pixels 1P among the plurality of pixels 1P.
Only the main components are shown. FIG. 6 is a cross-sectional view taken along the line YY in FIGS. 2 and 5 and shows only one pixel 1P among the plurality of pixels 1P. In FIGS. 5 and 6,
Components similar to those shown in FIGS. 1, 2, and 4 are referred to with the same reference numerals.

In the present embodiment, instead of the capacitor electrode 22 in the first embodiment, a black matrix 23 as shown in FIG. 5 is also used as a capacitor electrode, and is disposed on the second transparent substrate 20. The black matrix 23 is a light-shielding conductive material having a light-shielding property and having a lower resistance value than a transparent conductive material such as ITO or IZO, and is composed of, for example, a laminate of a chromium layer and a chromium oxide layer. .

As shown in FIGS. 5 and 6, the black matrix 23 covers the boundary between the adjacent pixels 1 </ b> P and extends so as to overlap at least the linear portion of the pixel electrode 18 disposed at the end of each pixel 1 </ b> P. Covering these. The black matrix 23 has an opening 23S that opens an area contributing to display of each pixel 1P. A voltage applying means 103 is connected to the black matrix 23, and a potential SC is applied from the voltage applying means 103. Potential S
C is preferably the same potential as the common potential COM applied to the common electrode 17. In this liquid crystal display device, the auxiliary capacitor Cs of each pixel 1P is configured with the pixel electrode 18 as a first capacitor electrode, the liquid crystal layer LC as a capacitor insulating layer, and the black matrix 23 as a second capacitor electrode.

In this case, since the area of the black matrix 23 that functions as a capacitor electrode is smaller than the area of the capacitor electrode 22 of the first embodiment, the area of the liquid crystal layer LC that functions as a capacitor insulating layer is also reduced. The capacitance value of the capacitor Cs is also reduced. Accordingly, the capacitance value of the auxiliary capacitor Cs is increased by setting the cell gap to be smaller than that of the first embodiment, for example, about 1.5 μm. Thereby, the auxiliary capacitor Cs can be configured to obtain the same effect as that of the first embodiment. Since other configurations are the same as those of the first embodiment, description thereof is omitted.
[Third Embodiment]
Note that, as the third embodiment of the present invention, the first embodiment and the second embodiment may be combined and implemented as one liquid crystal display device. This case will be described below with reference to the drawings. FIG. 7 is a cross-sectional view of the liquid crystal display device according to the present embodiment.
5 corresponds to a cross section taken along lines XX and YY in FIG. In FIG. 7, a plurality of pixels 1P
Only one pixel 1P is shown.

In the present embodiment, the black matrix 23 covers the boundary of the adjacent pixel 1P, and extends so as to overlap at least the linear portion of the pixel electrode 18 disposed at the end of each pixel 1P.
A black matrix portion covering these is provided. Opening 23 of black matrix 23
In S, the capacitor electrode 22 extends to face each linear portion of the pixel electrode 18. Capacitance electrode 22
A plurality of slit portions 22S are provided between the linear portions. In addition, a voltage applying unit 103 is connected to both the capacitive electrode 22 and the black matrix 23, and the voltage applying unit 103 is connected.
To the potential SC.

In this liquid crystal display device, the auxiliary capacitor Cs of each pixel 1P is configured such that the pixel electrode 18 is a first capacitor electrode, the liquid crystal layer LC is a capacitor insulating layer, and the capacitor electrode 22 and the black matrix 23 are second capacitor electrodes. Is done.

In this case, since the area of the black matrix 23 that functions as a capacitor electrode can be made larger than the area of the capacitor electrode 22 of the first embodiment, the liquid crystal layer LC that functions as a capacitor insulating layer.
And the capacity value of the auxiliary capacitor Cs can be increased accordingly. Utilizing this, the auxiliary capacitor Cs is configured to obtain the same effect as that of the first embodiment even when the upper limit of the cell gap is larger than that of the first embodiment, for example, about 2.5 μm. be able to. The birefringence Δn of the liquid crystal layer LC corresponding to this is, for example, about 0.12. Since other configurations are the same as those in the first embodiment and the second embodiment, description thereof is omitted.

In the present embodiment, the capacitor electrode 22 and the black matrix 23 are made of materials having different resistance values, and may be electrically connected to each other in order to reduce their resistance values. Below, an example of the connection structure of both in this case is demonstrated with reference to drawings. FIG. 8 is a cross-sectional view showing the liquid crystal display device according to the present embodiment, and is a partially enlarged view near the boundary of the pixel 1P.

On the second transparent substrate 20 at the boundary between adjacent pixels 1P, for example, a chromium oxide layer 23 is formed.
A black matrix 23 that is a laminate of A and the chromium layer 23B is disposed. A color filter 24 is disposed in the opening 23 </ b> S of the black matrix 23 so as to cover the end of the black matrix 23. That is, the color filter 24 is provided with an opening 24 </ b> S that opens a part of the black matrix 23. On the color filter 24, a capacitive electrode 22 including a linear portion is disposed. The capacitor electrode 22 arranged at the boundary of the pixel 1P is connected to the black matrix through the opening 24S. The capacitor electrode 22 is covered with the second alignment film 25.
In this case, either one or both of the capacitive electrode 22 and the black matrix 23 are connected to the voltage applying unit 103.

In each of the above embodiments, the liquid crystal layer LC has a negative dielectric anisotropy Δε, but the present invention is not limited to this, and the liquid crystal layer LC has a positive dielectric anisotropy Δε. This also applies to cases. In this case, in the region sandwiched between the pixel electrode 18 and the capacitor electrode 22, the liquid crystal layer LC
Since the liquid crystal molecules M are aligned in a direction substantially perpendicular to the first transparent substrate 10, the display quality is slightly lowered. However, since the other regions are oriented substantially horizontally with respect to the first transparent substrate 10, the same effects as described above can be obtained.

1 is an equivalent circuit diagram of a liquid crystal display device according to a first embodiment of the present invention. 1 is a plan view showing a liquid crystal display device according to a first embodiment of the present invention. 1 is a plan view showing a liquid crystal display device according to a first embodiment of the present invention. It is sectional drawing which shows the liquid crystal display device by the 1st Embodiment of this invention. It is a top view which shows the liquid crystal display device by the 2nd Embodiment of this invention. It is sectional drawing which shows the liquid crystal display device by the 2nd Embodiment of this invention. It is sectional drawing which shows the liquid crystal display device by the 3rd Embodiment of this invention. It is sectional drawing which shows the liquid crystal display device by the 3rd Embodiment of this invention. It is sectional drawing which shows the liquid crystal display device by a prior art example.

Explanation of symbols

1P pixel
DESCRIPTION OF SYMBOLS 10 1st transparent substrate 11 1st polarizing plate 12A 1st semiconductor layer 12B 2nd semiconductor layer 12D Drain region 12S Source region 13 Gate insulating film 14 Interlayer insulating film 15 Electrode 16 Planarization film 17 Common electrode 18 Pixel electrode DESCRIPTION OF SYMBOLS 19 1st alignment film 20 2nd transparent substrate 21 2nd polarizing plate 22 Capacitance electrode 22S Slit part 23 Black matrix 23A Chromium oxide layer 23B Conductive layer 23S Opening part 24 Color filter 25 2nd alignment film 101 Vertical drive circuit 102 horizontal drive circuit 103 voltage application means BL light source LC liquid crystal layer M liquid crystal molecule TR pixel transistor GL pixel selection signal line DL display signal line

Claims (8)

A plurality of pixels, each pixel being
A liquid crystal layer sandwiched between a first substrate and a second substrate;
A common electrode disposed on the first substrate and applied with a common potential;
Pixel electrodes alternately arranged on the first substrate with respect to the common electrode and to which a display signal is applied;
A counter electrode having a linear portion disposed on the second substrate and extending opposite to the at least one pixel electrode and having an opening in a region not overlapping with the pixel electrode. Liquid crystal display device. The liquid crystal display device according to claim 1, wherein the liquid crystal layer has negative dielectric anisotropy. 2. The counter electrode according to claim 1, wherein the counter electrode includes a plurality of linear portions extending facing the plurality of pixel electrodes, and a plurality of slit portions that open areas not overlapping with the pixel electrodes. Item 3. A liquid crystal display device according to Item 2. The liquid crystal display device according to claim 1, wherein the counter electrode constitutes an auxiliary capacitor together with the pixel electrode and the liquid crystal layer. The said counter electrode is formed with the light-shielding electroconductive material which covers the boundary of each pixel, and extends facing at least the said pixel electrode arrange | positioned at the edge part of each pixel. 2. A liquid crystal display device according to 2. The counter electrode covers a plurality of linear portions extending facing the plurality of pixel electrodes, a plurality of slit portions that open areas that do not overlap with the pixel electrodes, a boundary between the pixels, and at least each pixel. The liquid crystal display device according to claim 1, further comprising: a conductive light-shielding portion that extends opposite to the pixel electrode disposed at an end portion. The linear part is made of a conductive translucent material, the light shielding part is made of a material having a lower resistance than the linear part, and the linear part and the light shielding part are electrically connected. The liquid crystal display device according to claim 6. The common potential is applied to the counter electrode.
The liquid crystal display device according to any one of 4, 5, 6, and 7.

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