KR20060116580A - Liquid crystal display - Google Patents

Abstract

An LCD is provided to uniformly incline liquid crystal molecules, which are disposed above a thin film transistor substrate, thereby realizing excellent visibility, by forming serrated fine patterns on one side of a pixel electrode. A gate line(22) is extended in a first direction on a first insulating substrate. A data line(62) is extended across the gate line, and has a bending portion and an extension portion extended in a second direction. A pixel electrode(82) is formed in a pixel region defined by crossing of the gate line and the data line. Serrated fine patterns are formed on one side of the pixel electrode along the data line. A thin film transistor is electrically connected to the gate line, the data line, and the pixel electrode. A second insulating substrate is disposed to face the first insulating substrate. A common electrode is formed on the second insulating substrate. A liquid crystal layer is interposed between the first insulating substrate and the second insulating substrate.

Description

Liquid crystal display

1A is a layout view of a thin film transistor array panel for a liquid crystal display according to a first exemplary embodiment of the present invention.

1B is a layout view of a common electrode display panel for a liquid crystal display according to a first exemplary embodiment of the present invention.

FIG. 1C is a layout view of a liquid crystal display including the thin film transistor array panel of FIG. 1A and the common electrode display panel of FIG. 1B.

FIG. 2A is a cross-sectional view taken along line IIa-IIa 'of FIG. 1A.

FIG. 2B is a cross-sectional view taken along lines IIb-IIb 'and IIb'-IIb' of FIG. 1A.

FIG. 2C is a cross-sectional view taken along line IIc-IIc ′ of FIG. 1C.

FIG. 2D is a schematic perspective view of part A of FIG. 1C.

3A is a layout view of a liquid crystal display according to a second exemplary embodiment of the present invention.

3B is a cross-sectional view taken along line IIIb-IIIb ′ of the liquid crystal display of FIG. 3A.

4A is a layout view of a thin film transistor array panel for a liquid crystal display according to a third exemplary embodiment of the present invention.

4B is a layout view of a common electrode display panel of the liquid crystal display according to the third exemplary embodiment of the present invention.

4C is a layout view of a liquid crystal display including the thin film transistor array panel of FIG. 4A and the common electrode panel of FIG. 4B.

4D is a cross-sectional view taken along line IVd-IVd 'of the liquid crystal display of FIG. 4C.

4E is a circuit diagram of a liquid crystal display according to a third embodiment of the present invention.

5A is a layout view of a thin film transistor array panel for a liquid crystal display according to a fourth exemplary embodiment of the present invention.

5B is a layout view of a common electrode panel of the liquid crystal display according to the fourth exemplary embodiment of the present invention.

FIG. 5C is a layout view of a liquid crystal display including the thin film transistor array panel of FIG. 5A and the common electrode panel of FIG. 5B.

FIG. 5D is a cross-sectional view taken along line Vd-Vd ′ of the liquid crystal display of FIG. 5C.

5E is a circuit diagram of a liquid crystal display according to a fourth embodiment of the present invention.

6 is a layout view of a liquid crystal display according to a fifth exemplary embodiment of the present invention.

7 is a layout view of a liquid crystal display according to a sixth exemplary embodiment of the present invention.

8 is a layout view of a liquid crystal display according to a seventh exemplary embodiment of the present invention.

(Explanation of symbols for the main parts of the drawing)

1: thin film transistor display panel 2: color filter display panel

3: liquid crystal layer 5: liquid crystal molecules

22, 22a, 22b: gate line 24, 24a, 24b: gate line end

26, 26a, 26b: gate electrode 28: sustain electrode line

29: sustain electrode 40, 40a, 40b: semiconductor layer

62: data lines 65, 65a, 65b: source electrode

66, 66a, 66b: drain electrode 68: data line end

74, 74a, 74b, 76, 76a, 76b, 78: contact hole

82, 482, 582, 682, 782, 882: pixel electrode

83: incision 483, 583, 783, 883: gap

86, 86a, 86b: end of auxiliary gate line 88: end of auxiliary data line

120: black matrix 130: color filter

140: common electrode 142, 542, 642: cutout

The present invention relates to a display device, and more particularly, to a liquid crystal display device.

The liquid crystal display is one of the most widely used flat panel display devices. The liquid crystal display includes two display panels on which field generating electrodes such as a pixel electrode and a common electrode are formed, and a liquid crystal layer interposed therebetween. Is applied to generate an electric field in the liquid crystal layer, thereby determining the orientation of liquid crystal molecules in the liquid crystal layer and controlling the polarization of incident light to display an image.

Among them, the vertical alignment mode liquid crystal display in which the long axis of the liquid crystal molecules are arranged perpendicular to the upper and lower display panels without an electric field applied to the display panel has a high contrast ratio and is easy to implement a wide reference viewing angle. Here, the reference viewing angle refers to a viewing angle having a contrast ratio of 1:10 or a luminance inversion limit angle between gray levels.

Means for implementing a wide viewing angle in a vertical alignment mode liquid crystal display include a method of forming a cutout in the field generating electrode and a method of forming a protrusion on the field generating electrode. As described above, since one pixel is divided into a plurality of domains by using cutouts or protrusions, the direction in which the liquid crystal molecules are tilted by the cutouts or protrusions may be determined. The reference viewing angle can be widened.

When the pixel electrode is divided into a plurality of domains in order to obtain a wide viewing angle as described above, as the number of domains constituting one pixel increases, the aperture ratio decreases and the luminance decreases. On the other hand, as the number of domains constituting one pixel decreases, the aperture ratio increases, but the electrode spacing (domain width) increases, making it difficult to effectively control the liquid crystal. Therefore, the liquid crystal orientation is unstable, resulting in texture, resulting in reduced luminance. In addition, the response speed is lowered.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a liquid crystal display device capable of simultaneously improving response speed and luminance.

The technical problems of the present invention are not limited to the above-mentioned technical problems, and other technical problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to an exemplary embodiment of the present invention, a liquid crystal display device includes a first insulating substrate, a gate line formed on the first insulating substrate and extending in a first direction, and the gate on the first insulating substrate. A data line having an insulated intersection with the line, having a curved portion and a portion extending in the second direction, and formed for each pixel defined by the gate line and the data line crossing each other, and having a sawtooth shape along at least one side along the data line. A pixel electrode having a pattern formed thereon, a thin film transistor connected to the gate line, the data line and the pixel electrode, a second insulating substrate facing the first insulating substrate, a common electrode formed on the second insulating substrate, and And a liquid crystal layer injected between the first insulating substrate and the second insulating substrate.

In addition, the liquid crystal display according to another embodiment of the present invention for achieving the above technical problem, a first insulating substrate, a gate line formed on the first insulating substrate extending in the first direction, and on the first insulating substrate A first pixel formed to insulate and intersect the gate line, the data line having a curved portion and a portion extending in a second direction, and each pixel defined by the gate line and the data line crossing each other, and having a sawtooth-shaped fine pattern formed thereon; A thin film transistor connected to one of the first and second pixel electrodes, a second pixel electrode formed in each of the pixels and capacitively coupled to the first pixel electrode, and connected to the gate line and the data line A second insulating substrate facing the first insulating substrate, a common electrode formed on the second insulating substrate, and the first insulating substrate; And a liquid crystal layer injected between the second insulating substrates.

In addition, the liquid crystal display according to another embodiment of the present invention for achieving the above technical problem, the first insulating substrate, the first and second gate lines extending in the first direction formed on the first insulating substrate, A data line formed on the first insulating substrate so as to be insulated from and intersecting the first and second gate lines, the data line having a bent portion and a portion extending in the second direction, and the first and second gate lines and the data line defined to cross each other. First and second pixel electrodes formed for each pixel, the first and second pixel electrodes having a sawtooth-shaped fine pattern formed on the first pixel electrode, and the first gate line, the first pixel electrode, and the data electrode. A first thin film transistor connected to the second thin film transistor connected to the second gate line, the second pixel electrode and the data electrode, and a second insulator facing the first insulating substrate. And includes a common electrode, and the first insulating layer of the liquid crystal injected between the substrate and the second insulating substrate formed on the second insulating substrate.

Specific details of other embodiments are included in the detailed description and the drawings.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, only the embodiments are to make the disclosure of the present invention complete, and the general knowledge in the art to which the present invention belongs It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

Hereinafter, a liquid crystal display according to a first exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings with reference to FIGS. 1A to 2D. FIG. 1A is a layout view of a thin film transistor array panel for a liquid crystal display according to a first embodiment of the present invention, and FIG. 1B is a layout view of a common electrode display panel for a liquid crystal display according to a first embodiment of the present invention, and FIG. FIG. 1B is a layout view of a liquid crystal display device including the thin film transistor array panel and the common electrode display panel of FIG. 1B. 2A is a cross-sectional view taken along line IIa-IIa 'of FIG. 1A, FIG. 2B is a cross-sectional view taken along lines IIb-IIb' and IIb'-IIb 'of FIG. 1A, and FIG. 2C is a line IIc- of FIG. 1C. FIG. 2D is a schematic perspective view of the portion A of FIG. 1C. FIG.

As shown in FIG. 2C, the liquid crystal display according to the first exemplary embodiment of the present invention is formed between the thin film transistor array panel 1, the common electrode panel 2 facing each other, and the two display panels 1 and 2. The long axis of the liquid crystal molecules 5 contained therein consists of the liquid crystal layer 3 which is oriented almost perpendicular to these display panels 1, 2.

First, a thin film transistor array panel will be described in more detail with reference to FIGS. 1A, 2A, and 2B.

The gate line 22 is formed in the horizontal direction on the insulating substrate 10, and the gate electrode 26 formed in the form of a protrusion is formed on the gate line 22. At the end of the gate line 22, a gate line end 24 for receiving a gate signal from another layer or the outside and transmitting the gate signal to the gate line 22 is formed, and the gate line end 24 is connected to an external circuit. The width is expanded for The gate line 22, the gate electrode 26, and the gate line end 24 are referred to as gate wirings.

In addition, the storage electrode line 28 and the storage electrode 29 are formed on the insulating substrate 10. The storage electrode line 28 extends in the horizontal direction across the pixel region, and the storage electrode line 28 is formed with a storage electrode 29 having a wider width than the storage electrode line 28. However, the sustain electrode line 28 and the sustain electrode 29 are called sustain electrode wirings, and the shape and arrangement of the sustain electrode wirings may be modified in various forms.

The gate wirings 22, 24, 26 and the sustain electrode wirings 28, 29 may be formed of aluminum-based metals such as aluminum (Al) and aluminum alloys, silver-based metals such as silver (Ag) and silver alloys, and copper (Cu) and the like. Copper-based metals such as copper alloys, molybdenum (Mo) and molybdenum-based metals such as molybdenum alloys, it may be made of chromium (Cr), titanium (Ti), tantalum (Ta). In addition, the gate wirings 22, 24, 26 and the sustain electrode wirings 28, 29 may have a multilayer structure including two conductive films (not shown) having different physical properties. One of the conductive films is a low resistivity metal such as an aluminum-based metal or a silver-based metal so as to reduce the signal delay or voltage drop of the gate wirings 22, 24, and 26 and the sustain electrode wirings 28 and 29. It consists of a metal, a copper type metal, etc. In contrast, the other conductive layer is made of a material having excellent contact properties with other materials, particularly indium tin oxide (ITO) and indium zinc oxide (IZO), such as molybdenum-based metals, chromium, titanium, tantalum and the like. A good example of such a combination is a chromium bottom film and an aluminum top film and an aluminum bottom film and a molybdenum top film. However, the present invention is not limited thereto, and the gate wirings 22, 24, and 26 and the sustain electrode wirings 28 and 29 may be made of various metals and conductors.

The gate insulating film 30 is formed on the gate wirings 22, 24, 26 and the sustain electrode wirings 28, 29.

On the gate insulating film 30, a semiconductor layer 40 made of hydrogenated amorphous silicon, polycrystalline silicon, or the like is formed. The semiconductor layer 40 may have various shapes such as an island shape and a linear shape. For example, the semiconductor layer 40 may be formed in an island shape on the gate electrode 26 as in the present embodiment. In addition, when the semiconductor layer 40 is linearly formed, the semiconductor layer 40 may be positioned below the data line 62 and extend to the upper portion of the gate electrode 26.

An island-type ohmic contact layer and a linear ohmic contact layer made of a material such as n + hydrogenated amorphous silicon doped with silicide or n-type impurities at a high concentration are formed on the semiconductor layer 40. The ohmic contact layers 55 and 56 of the present embodiment are island type ohmic contact layers and are disposed under the drain electrode 66 and the source electrode 65. In the case of the linear ohmic contact layer, it extends to the bottom of the data line 62.

The data line 62 and the drain electrode 66 are formed on the ohmic contacts 55 and 56 and the gate insulating layer 30. The data line 62 extends long and crosses the gate line 22 to define a pixel. A source electrode 65 extending from the data line 62 to the top of the ohmic contact layer 55 in a branch form is formed. The data line end 68 is formed at the end of the data line 62 to receive a data signal from another layer or the outside and to transmit the data signal to the data line 62. The data line end 68 is connected to an external circuit. The width is expanded for The drain electrode 66 is separated from the source electrode 65 and is positioned over the ohmic contact layer 56 opposite the source electrode 65 with respect to the gate electrode 26. Such data line 62, data line end 68, and source electrode 65 are referred to as data lines.

Here, the data line 62 is formed such that the curved portion and the vertically extending portion appear repeatedly with the length of the pixel. At this time, the curved portion of the data line 62 is composed of two straight portions, one of these two straight portions forms 45 degrees with respect to the gate line 22, and the other portion is formed on the gate line 22. To -45 degrees. The source electrode 65 is connected to the vertically extending portion of the data line 62, and the portion intersects the gate line 22 and the storage electrode line 28.

At this time, the ratio of the lengths of the bent portion and the vertically extending portion of the data line 62 is between 1: 1 and 9: 1 (that is, the ratio of the bent portion of the data line 62 is between 50% and 90%). Is preferable.

Therefore, the pixel formed by the intersection of the gate line 22 and the data line 62 is formed in a band shape. As described above, the data line 62 may be formed by a combination of a straight line and a curved band like the shape of a pixel. However, the present invention is not limited thereto, and the data line 62 may be simply formed as a straight line or a curved band.

In addition, the drain electrode 66 is formed so as to overlap with the sustain electrode 29, and the storage capacitor is formed by overlapping the sustain electrode 29 with the gate insulating film 30 therebetween.

The data line 62, the source electrode 65, and the drain electrode 66 are preferably made of a refractory metal such as chromium, molybdenum-based metal, tantalum, and titanium, and a lower layer (not shown) such as a refractory metal and the like. It may have a multi-layer structure consisting of a low-resistance material upper layer (not shown) located. Examples of the multilayer film structure include a triple film of molybdenum film, aluminum film, and molybdenum film in addition to the above-described double film of chromium lower film and aluminum upper film or aluminum lower film and molybdenum upper film.

The source electrode 65 overlaps at least a portion of the semiconductor layer 40, and the drain electrode 66 faces the source electrode 65 around the gate electrode 26 and at least partially overlaps the semiconductor layer 40. do. Here, the ohmic contacts 55 and 56 exist between the lower semiconductor layer 40 and the source electrode 65 and the drain electrode 66 above and serve to lower the contact resistance.

The drain electrode 66 has a rod-shaped end portion overlapping the semiconductor layer 40 and a large drain electrode extension 67 extending therefrom and overlapping the storage electrode 29.

A passivation layer 70 made of an organic insulating layer is formed on the data line 62, the drain electrode 66, and the exposed semiconductor layer 40. The protective film 70 is an inorganic material made of silicon nitride or silicon oxide, an organic material having excellent planarization characteristics and photosensitivity, or a-Si: C: O formed by plasma enhanced chemical vapor deposition (PECVD). and a low dielectric constant insulating material such as a-Si: O: F. In addition, the passivation layer 70 may have a double layer structure of the lower inorganic layer and the upper organic layer in order to protect the exposed portion of the semiconductor layer 40 while maintaining excellent characteristics of the organic layer.

In the passivation layer 70, contact holes 78 and 76 are formed to expose the data line end 68 and the drain electrode extension 67, respectively. The contact hole 74 which exposes the line end 24 is formed. A band-shaped pixel electrode 82 electrically connected to the drain electrode 66 through the contact hole 76 and bent along the shape of the pixel is formed.

In addition, the auxiliary gate line end 86 and the auxiliary data line end 88, which are connected to the gate line end 24 and the data line end 68, respectively, through the contact holes 74 and 78 on the passivation layer 70. Formed. Here, the pixel electrode 82, the auxiliary gates, and the data line ends 86 and 88 are made of a transparent conductor such as ITO or IZO or a reflective conductor such as aluminum. The auxiliary gate line and the data line ends 86 and 88 serve to protect adhesion between the gate line end 24 and the data line end 68 and the external device.

The pixel electrode 82 is physically and electrically connected to the drain electrode 66 through the contact hole 76 to receive a data voltage from the drain electrode 66.

The pixel electrode 82 to which the data voltage is applied generates an electric field together with the common electrode of the upper panel to determine the arrangement of liquid crystal molecules of the liquid crystal layer between the pixel electrode 82 and the common electrode.

The pixel electrode 82 includes a first pixel electrode 82a and a second pixel electrode 82b separated by cutouts 83 formed side by side along the data line 62. Here, the first pixel electrode 82a and the second pixel electrode 82b are electrically connected to each other. A protrusion may be formed at the position of the cutout 83, and the cutout 83 or the protrusion is called a domain dividing means. The cutout 83 vertically divides the pixel area by approximately 1: 2 and forms approximately 45 degrees or −45 degrees with the gate line 22. A sawtooth-shaped fine pattern is formed on the first pixel electrode 82a which occupies a narrow area among the pixel electrodes 82 divided by the cutouts 83. In the present exemplary embodiment, the first pixel electrode 82a is formed on the right side of the cutout 83, but the present invention is not limited thereto and may be formed on the left side of the cutout 83. The first pixel electrode 82a is formed of a sawtooth-shaped fine pattern arranged side by side along the cutout 83, more preferably a plurality of trapezoidal fine patterns. The sawtooth fine pattern of the present invention can be variously modified, but for convenience of description it will be described using a trapezoidal fine pattern. As will be described in detail later, the trapezoidal fine pattern formed on the first pixel electrode 82a may form a lateral field in a specific direction to determine the arrangement of the liquid crystal molecules of the liquid crystal layer.

An alignment layer (not shown) capable of orienting the liquid crystal layer 3 may be coated on the pixel electrode 82, the auxiliary gate lines, the data line ends 86 and 88, and the passivation layer 70.

Hereinafter, the common electrode display panel will be described with reference to FIGS. 1B, 1C, and 2C.

On the bottom surface of the insulating substrate 110 made of a transparent insulating material such as glass, a black matrix 120 for preventing light leakage and red, green, and blue color filters 130 arranged in sequence on the pixels are formed. The overcoat layer 150 made of an organic material is formed on the color filter 130. On the overcoat layer 150, a common electrode 140 made of a transparent conductive material such as ITO or IZO and having a cutout 142 is formed. In this case, the cutout 142 has a curved shape along the curved shape of the pixel.

At this time, the cutout 142 acts as a domain regulating means and the width thereof is preferably between 9 µm and 12 µm. If the organic projections are formed instead of the cutout 142 by domain regulating means, it is preferable to set the width between 5 μm and 10 μm.

The black matrix 120 may include a linear portion corresponding to the curved portion of the data line 62, a vertically extending portion of the data line 62, and a triangular portion corresponding to the thin film transistor portion.

The color filter 130 is formed lengthwise along the pixel column partitioned by the black matrix 120, and is bent periodically along the shape of the pixel.

The common electrode 140 faces the pixel electrode 82 and has a cutout 142 that is inclined at approximately 45 degrees or −45 degrees with respect to the gate line 22. The cutout 142 of the common electrode 140 is also bent to form the shape of dividing the curved pixel from side to side. A protrusion may be formed at the position of the cutout 142, and the cutout 142 or the protrusion is called a domain dividing means.

On the common electrode 140 may be coated an aviation layer (not shown) to align the liquid crystal molecules 5.

FIG. 1C is a layout view of a liquid crystal display including the thin film transistor array panel of FIG. 1A and the common electrode display panel of FIG. 1B, wherein the cutout 142 of the common electrode 140 is formed with the cutout 83 of the pixel electrode 82. It is arranged in the center of the data line 62. That is, the cutout 142 of the common electrode 140 is arranged on the second pixel electrode 82b having no fine pattern.

When the thin film transistor array panel 1 and the common electrode panel 2 having such a structure are aligned and combined, and the liquid crystal layer 3 is formed therebetween to form a vertical alignment, the liquid crystal display according to the first exemplary embodiment of the present invention is a basic element. The structure is made.

The liquid crystal molecules 5 included in the liquid crystal layer 3 have directors of the thin film transistor array panel 1 and the common electrode display panel 2 when an electric field is not applied between the pixel electrode 82 and the common electrode 140. Oriented perpendicular to, and have negative dielectric anisotropy. The thin film transistor array panel 1 and the common electrode display panel 2 are aligned such that the pixel electrode 82 is exactly overlapped with the color filter 130. In this way, the pixel is divided into a plurality of domains by the cutout 142 of the common electrode 140 and the cutout 83 of the pixel electrode 82. At this time, the pixel is divided into left and right sides by the cutouts 83 and 142, but is divided into six types of domains in which the alignment directions of the liquid crystals are different from each other up and down around the bent portion of the pixel. That is, the pixel is divided into six kinds of domains according to the direction in which the main directors of the liquid crystal molecules included in the liquid crystal layer are arranged when the electric field is applied.

At this time, it is preferable that the distance between two long sides of the domain, that is, the width W1 of the domain, is between 20 μm and 40 μm.

The liquid crystal display device is formed by disposing elements such as a polarizing plate, a backlight, and a compensation plate in this basic structure.

In this case, one polarizer (not shown) is disposed on each side of the basic structure, and the transmission axis thereof is disposed so that one of them is parallel to the gate line 22 and the other is perpendicular to each other.

When the liquid crystal display device is formed as described above, when an electric field is applied to the liquid crystal, the liquid crystal in each domain is inclined in a direction perpendicular to the long side of the domain. However, since the direction is perpendicular to the data line 62, the liquid crystal is inclined by a lateral field formed between two adjacent pixel electrodes 82 with the data line 62 therebetween. By coinciding with the direction, the lateral electric field assists the liquid crystal alignment of each domain.

The liquid crystal display generally uses inversion driving methods such as point inversion driving, thermal inversion driving, and two-point inversion driving, which apply voltages having opposite polarities to pixel electrodes positioned on both sides of the data line 62. Almost always occurs and the direction is the direction that helps the liquid crystal alignment of the domain.

In addition, since the transmission axis of the polarizing plate is disposed in a direction perpendicular to or parallel to the gate line 22, the polarizing plate can be manufactured at low cost, and the alignment direction of the liquid crystal is 45 degrees with the transmission axis of the polarizing plate in all domains, thereby obtaining the highest luminance. Can be.

However, the length of the wiring increases because the data line 62 is bent. When the bent portion of the data line 62 occupies 50%, the length of the wiring increases by about 20%. When the length of the data line 62 is increased, the resistance and load of the wiring are increased, thereby increasing signal distortion. However, in the ultra-high opening ratio structure, the width of the data line 62 can be formed sufficiently wide, and since the thick organic protective film 70 is used, the load of the wiring is small enough, so that the signal distortion problem caused by the increase in the length of the data line 62 can be ignored. Can be.

On the other hand, each of the thin film transistor array panel 1 and the common electrode display panel 2 includes an alignment layer (not shown) for orienting the liquid crystal molecules 5. In this case, the alignment layer (not shown) has a characteristic for vertically aligning the liquid crystal molecules 5, and may not be.

Hereinafter, a first pixel electrode in which a fine pattern is formed in the liquid crystal display according to the first exemplary embodiment of the present invention will be described in detail with reference to FIGS. 1C, 2C, and 2D.

As described above, when an electric field is applied to the liquid crystal molecules 5 in the liquid crystal display having a plurality of domain division structures, the liquid crystal in each domain is inclined in a direction perpendicular to the long side of the domain. That is, as shown in FIG. 2C, the liquid crystal molecules 5 of the domain D1 are inclined to the right, and the liquid crystal molecules 5 of the domain D2 are inclined to the left. That is, the liquid crystal molecules 5 positioned in the domain D1 are inclined to the right by receiving the lateral electric field in the same direction by the inter-pixel gap 202 and the cutout 142 of the common electrode 140. In addition, the liquid crystal molecules 5 positioned in the domain D2 receive the lateral electric field in the same direction by the cutout 142 of the common electrode 140 and the cutout 83 of the pixel electrode 82. Inclined

If a separate pattern is not formed in the first pixel electrode 82a positioned in the domain D3, the orientation of the liquid crystal molecules 5 in the domain D3 is unstable, resulting in texture. That is, the liquid crystal molecules 5 located on the left side of the domain D3 are inclined to the right by the lateral electric field generated by the cutout 83 and are positioned on the right side of the domain D3. ) Is inclined to the left by the lateral electric field generated by the inter-pixel gap 204, so that the liquid crystal molecules 5 located in the middle portion of the domain D3 have unstable directionality.

The first pixel electrode 82a of the liquid crystal display according to the first exemplary embodiment of the present invention is composed of a plurality of trapezoidal fine patterns arranged side by side along the cutout 83. The motion of the liquid crystal located in the domain D3 will be described in detail with reference to FIG. 2D.

The fine pattern constituting the first pixel electrode 82a includes an upper side 281, a lower side 283 substantially parallel to the upper side 281, a first side 283 and a second side 284. Here, although the lower side 283 of each trapezoid is electrically connected to each other, the present invention is not limited thereto, and even if the upper side 281 of each quadrilateral is electrically connected to each other, the same effect and effect can be obtained.

Consider the lateral electric field (XY direction) generated by the vertical direction (Z-axis direction) electric field formed between the common electrode 140 and the first pixel electrode 82a and the shape of the fine pattern of the first pixel electrode 82a. Looking at the movement of the liquid crystal molecules (5) arranged vertically as follows. The liquid crystal molecules 5 positioned on the upper side 281 of the fine pattern are inclined in the Y direction, and the liquid crystal molecules 5 positioned on the upper side of the first side 283 of the fine pattern are inclined in the X · Y direction. The liquid crystal molecules 5 located above the second side edge 284 of the fine pattern are inclined in the (-X) -Y direction. Here, the forces in the X direction and the (-X) direction cancel each other and the liquid crystal molecules 5 positioned on the fine pattern are inclined in the Y direction, that is, the direction perpendicular to the long side of the incision 83 or the domain as a whole. You lose. Therefore, the liquid crystal molecules 5 positioned on the lower side 282 of the fine pattern also move in the Y direction.

However, the lateral electric field generated by the cutout 83 tries to tilt the liquid crystal molecules 5 positioned above the first pixel electrode 82a adjacent to the cutout 83 in the (-Y) direction, but the fine pattern The liquid crystal molecules 5 on the upper side 281, the first side 283 and the second side 284 constituting the surface are inclined in the Y direction as a whole by the movement in the collective Y direction. Therefore, as shown in FIG. 2C, the liquid crystal molecules 5 in the domain D3 are inclined in the left direction by a trapezoidal fine pattern formed in the first pixel electrode 82a.

In general, the cutout 142 of the common electrode 140 and the cutout 83 of the pixel electrode 82 or the cutout 142 of the common electrode 140 and the inter-pixel gaps 202 and 204 are alternately arranged. In this case, no texture is generated in one domain. However, when the cutout 83 of the pixel electrode 82 and the inter-pixel gap 204 are arranged side by side and the cutout 142 of the common electrode 140 is not arranged therebetween, the lateral electric fields conflict with each other. As a result, the orientation of liquid crystal molecules in the domains located therebetween is unstable, resulting in texture. However, the cut portions 142 of the common electrode 140, the cut portions 83 of the pixel electrode 82, or the cut portions 83 of the pixel electrode 82 and the inter-pixel gap 204 are side by side. When arranged, the liquid crystal molecules can be arranged in a constant direction by forming the fine pattern mentioned in the present embodiment on the pixel electrode 82.

When the lateral electric field generated by the first pixel electrode 82a having a fine pattern is formed, rather than the lateral electric field using the cutouts 83 and 142 or the inter-pixel gaps 202 and 204, the liquid crystal molecules move more effectively. Can control the response speed. Therefore, even if the width (electrode spacing) W1 of the domain shown in FIG. 1C is increased, the movement of the liquid crystal molecules can be effectively controlled. For example, the width W1 of the domain of the liquid crystal display according to the exemplary embodiment may be formed to about 20-40 μm. Furthermore, when the raw gray level signal changes from black gray to white gray, the response of the liquid crystal by outputting the corrected gray level signal for pretilt generation and the corrected gray level signal for overshoot generation to the data line 62. Speed can be increased.

Here, the narrower the width of the trapezoidal pattern constituting the fine pattern, the more effectively the movement of the liquid crystal molecules can be controlled. For example, in consideration of the CD (Critical dimension) of the manufacturing process, the length La of the upper side 281 of the trapezoid is about 1-8 μm, and the length Lb of the lower side 282 is about 1-15 μm. It can be formed as.

Hereinafter, a structure for a liquid crystal display according to a second embodiment of the present invention will be described in detail with reference to FIGS. 3A and 3B. 3A is a layout view of a liquid crystal display according to a second exemplary embodiment of the present invention, and FIG. 3B is a cross-sectional view taken along line IIIb-IIIb 'of the liquid crystal display of FIG. 3A. For convenience of description, members having the same functions as the members shown in the drawings of the first embodiment are denoted by the same reference numerals, and therefore description thereof is omitted. As shown in FIGS. 3A and 3B, the liquid crystal display of the present embodiment has a basically identical structure to the liquid crystal display of FIGS. 1A to 2D except for the following.

That is, as shown in Fig. 3A, the first pixel electrode 82a of the left pixel and the first pixel electrode 82a 'of the right pixel are formed almost in reverse phase. That is, the upper and lower sides of the trapezoidal fine pattern of the first pixel electrode 82a and the upper and lower sides of the trapezoidal fine pattern of the second pixel electrode 82a 'are formed to be opposite to each other. Thus, as shown in FIG. 3B, the liquid crystal molecules 5 positioned in the domain D3 corresponding to the first pixel electrode 82a of the left pixel are inclined to the left and the first pixel electrode 82a of the right pixel is inclined. The liquid crystal molecules 5 located in the domain D3 'corresponding to') are tilted to the right.

As described above, by alternately forming fine patterns that are reversed with each other, the liquid crystal molecules positioned on the thin film transistor array panel may be uniformly inclined in four directions on the average to realize excellent visibility.

Hereinafter, the structure of the liquid crystal display according to the third exemplary embodiment of the present invention will be described in detail with reference to FIGS. 4A to 4E.

FIG. 4A is a layout view of a thin film transistor array panel for a liquid crystal display according to a third exemplary embodiment of the present invention. FIG. 4B is a layout view of a common electrode display panel of a liquid crystal display according to a third exemplary embodiment of the present invention. 4A is a layout view of a liquid crystal display including the thin film transistor array panel of FIG. 4A and the common electrode display panel of FIG. 4B, and FIG. 4D is a cross-sectional view taken along line IVd-IVd ′ of the liquid crystal display of FIG. 4C. 4E is a circuit diagram of a liquid crystal display according to a third embodiment of the present invention. For convenience of description, members having the same functions as the members shown in the drawings of the first embodiment are denoted by the same reference numerals, and therefore description thereof is omitted. As shown in FIGS. 4A to 4E, the liquid crystal display of the present exemplary embodiment basically has the same structure except for the liquid crystal display of FIGS. 1A to 2D, the pixel electrode 482, and the coupling electrode 464.

The coupling electrode 464 made of the same material is connected to the drain electrode 66 in the same layer as the drain electrode 66. The coupling electrode 464 may extend directly from the drain electrode 66, or may extend from the drain electrode extension 67 connected to the drain electrode 66 as shown in FIG. 4A. The coupling electrode 464 extends from the drain electrode 66 and is formed parallel to the curved portion of the data line 62. That is, the drain electrode 66 travels in the direction of 45 degrees with respect to the gate line 22 in parallel with the data line 62, and is bent once to a predetermined distance in the direction of -45 degrees with respect to the gate line 22. Is extended. The present invention is not limited to the shape of the coupling electrode 464 and may be applied to various types of coupling electrodes extending from the drain electrode 66 to the lower portion of the second pixel electrode 482b.

On the passivation layer 70, a pixel electrode 482 having a band shape bent along the shape of the pixel is formed. The pixel electrode 482 includes a first pixel electrode 482a and a second pixel electrode 482b electrically separated vertically by predetermined gaps 483 formed side by side along the data line 62. do. Here, the gap 483 divides the pixel region vertically into approximately 1: 2 and partitions the pixel region into the first pixel electrode 482a and the second pixel electrode 482b, and the gate line 22 is approximately 45 degrees or -45 degrees. To achieve

The same trapezoidal fine pattern as described in the first embodiment is formed on the first pixel electrode 482a. For the same reason as described in the first embodiment, the texture is prevented by effectively controlling the movement of the liquid crystal molecules by using the lateral electric field generated by the first pixel electrode 482a having the fine pattern as shown in FIG. 4D. And brightness can be improved. Furthermore, when the raw gray level signal changes from black gray to white gray, the response of the liquid crystal by outputting the corrected gray level signal for pretilt generation and the corrected gray level signal for overshoot generation to the data line 62. Speed can be increased.

The first pixel electrode 482a is connected to the drain electrode 66 through the contact hole 76. Although the second pixel electrode 482b is in an electrically floating state, the second pixel electrode 482b overlaps the coupling electrode 464 connected to the drain electrode 66 and is capacitively coupled to the first pixel electrode 482a. That is, the voltage of the second pixel electrode 482b is changed by the voltage applied to the first pixel electrode 482a. At this time, the voltage of the second pixel electrode 482b is always lower than the voltage of the first pixel electrode 482a. In the present exemplary embodiment, the structure in which the first pixel electrode 482a having the fine pattern and the drain electrode 66 are electrically connected to each other is described as an example. However, the present invention is not limited thereto, and the second pixel electrode 482b having the fine pattern is not limited thereto. The drain electrode 66 may be electrically connected to each other, and the first pixel electrode 482a and the coupling electrode 464 may be capacitively coupled. However, in order to improve visibility, it is advantageous to have a large area of the pixel electrode for capacitive coupling. Therefore, the first pixel electrode 482a and the drain electrode 66 having the fine pattern are electrically connected and the second pixel electrode 482b is formed. ) And the coupling electrode 464 are more preferably coupled capacitively. In addition, since the reduction of the aperture ratio due to the fine pattern can be almost neglected at a high voltage, it is advantageous that the first pixel electrode 482a and the drain electrode 66 are electrically connected in terms of transmittance. For convenience of description, the present invention will be described using a liquid crystal display device in which the first pixel electrode 482a having the fine pattern and the drain electrode 66 are electrically connected.

As such, when two pixel electrodes having different voltages are disposed in one pixel area, the two pixel electrodes compensate for each other to reduce distortion of the gamma curve. The coupling relationship between the first pixel electrode 482a and the second pixel electrode 482b will be described later with reference to FIG. 4E.

4B, 4C, and 4D, in the common electrode display panel for the liquid crystal display according to the third exemplary embodiment, the cutout 142 of the common electrode 140 is formed at the center of the second pixel electrode 482b. Are arranged in. That is, the cutout 142 of the common electrode 140 is arranged on the second pixel electrode 482b having no fine pattern.

In this way, the pixel is divided into a plurality of domains by the cutout 142 of the common electrode 140 and the gap 483 of the pixel electrode 482. At this time, the pixel is divided into left and right by the cutout 142 and the gap 483, but is divided into six types of domains in which the alignment directions of the liquid crystals are different from each other up and down around the bent portion of the pixel. That is, the pixel is divided into six kinds of domains according to the direction in which the main directors of the liquid crystal molecules included in the liquid crystal layer are arranged when the electric field is applied.

 In the liquid crystal display having the structure, the first pixel electrode 482a receives an image signal voltage through the thin film transistor, whereas the second pixel electrode 482b receives a voltage by capacitive coupling with the coupling electrode 464. Because of this variation, the absolute value of the voltage of the second pixel electrode 482b is always lower than that of the first pixel electrode 482a. As such, when two pixel electrodes 482a and 482b having different voltages are disposed in one pixel, the two pixel electrodes 482a and 482b compensate for each other to reduce distortion of the gamma curve.

Next, the reason why the voltage of the first pixel electrode 482a is lower than the voltage of the second pixel electrode 482b will be described with reference to FIG. 4E.

4E is a circuit diagram of a liquid crystal display according to a third exemplary embodiment of the present invention.

In FIG. 4E, Clca represents a liquid crystal capacitance formed between the first pixel electrode 482a and the common electrode 140, and Cst represents a storage formed between the first pixel electrode 482a and the storage electrode wirings 28 and 29. Capacity. Clcb represents a liquid crystal capacitor formed between the second pixel electrode 482b and the common electrode 140, and Ccp represents a coupling capacitor formed between the first pixel electrode 482a and the second pixel electrode 482b.

When the voltage of the first pixel electrode 482a with respect to the voltage of the common electrode 140 is referred to as Va, and the voltage of the second pixel electrode 482b as Vb, according to the voltage division law,

Va = Vb × [Ccp / (Ccp + Clcb)]

Since Ccp / (Ccp + Clcb) is always less than 1, Vb is always smaller than Va. The ratio of Vb to Va can be adjusted by adjusting Ccp. The adjustment of Ccp is possible by adjusting the overlapping area or distance of the coupling electrode 464 and the second pixel electrode 482b. The overlapping area can be easily adjusted by changing the width of the coupling electrode 464, and the distance can be adjusted by changing the formation position of the coupling electrode 464. That is, in the exemplary embodiment of the present invention, the coupling electrode 464 is formed on the same layer as the data line 62, but the coupling electrode 464 and the second pixel electrode 482b are formed on the same layer as the gate line 22. You can increase the distance between them. The arrangement of the coupling electrode 464 may be variously modified.

In addition, in the present embodiment, as described above with reference to FIGS. 3A and 3B, by forming alternately reversed fine patterns for each pixel, the liquid crystal molecules positioned on the thin film transistor array panel are inclined uniformly in four directions on the average to provide excellent visibility. Can be implemented.

Hereinafter, the structure of the liquid crystal display according to the fourth exemplary embodiment of the present invention will be described in detail with reference to FIGS. 5A to 5E.

FIG. 5A is a layout view of a thin film transistor array panel for a liquid crystal display according to a fourth exemplary embodiment of the present invention. FIG. 5B is a layout view of a common electrode display panel of a liquid crystal display according to a fourth exemplary embodiment of the present invention. FIG. 5D is a layout view of a liquid crystal display including the thin film transistor array panel of FIG. 5A and the common electrode display panel of FIG. 5B, and FIG. 5D is a cross-sectional view taken along line Vd-Vd ′ of the liquid crystal display of FIG. 5C, and FIG. 5E is a fourth embodiment of the present invention. It is a circuit diagram of the liquid crystal display device by an Example. For convenience of description, members having the same functions as the members shown in the drawings of the first embodiment are denoted by the same reference numerals, and therefore description thereof is omitted.

First, a thin film transistor array panel for a liquid crystal display according to a fourth embodiment of the present invention will be described in detail with reference to FIGS. 5A, 5C, and 5D.

A pair of first and second gate lines 22a and 22b and a storage electrode line 28 are formed on an insulating substrate 10 made of transparent glass or the like.

The first and second gate lines 22a and 22b mainly extend in the horizontal direction, are physically and electrically separated from each other, and transmit gate signals. The first and second gate lines 22a and 22b are disposed above and below each pixel, respectively. In addition, a pair of first and second gate electrodes 26a and 26b are formed on the first and second gate lines 22a and 22b, respectively. At the ends of the first and second gate lines 22a and 22b, gate lines are applied to the first and second gate lines 22a and 22b, respectively, and receive gate signals from other layers or from outside. Is formed. The gate line ends 24a and 24b have a large area for connection with the outside and are disposed on the left or right side with respect to the pixel area. As shown in FIGS. 5A and 5C, the gate line ends 24a and 24b may be disposed on the left side and the right side, respectively, but the present invention is not limited thereto and the gate line ends may be disposed on the left side or the right side. .

The storage electrode line 28 mainly extends in the horizontal direction, and the storage electrode line 28 is formed with a storage electrode 29 having a wider width than the storage electrode line 28. However, the shape and arrangement of the storage electrode line 28 and the storage electrode 29 may be modified in various forms.

The first and second gate lines 22a and 22b and the storage electrode line 28 may be formed of the same material as the gate line 22 of the first embodiment.

A gate insulating layer 30 made of silicon nitride (SiNx) is formed on the first and second gate lines 22a and 22b and the storage electrode line 28.

A pair of semiconductor layers 40a and 40b made of hydrogenated amorphous silicon, polycrystalline silicon, or the like are formed on the gate insulating film 30.

An ohmic contact layer made of a material such as n + hydrogenated amorphous silicon doped with a high concentration of silicide or n-type impurities is formed on each of the semiconductor layers 40a and 40b. The ohmic contacts are paired and positioned on the semiconductor layers 40a and 40b.

The data line 62 and a pair of first and second drain electrodes 66a and 66b are formed on each of the ohmic contact layer and the gate insulating film 30.

The data line 62 mainly extends in the vertical direction and crosses the first and second gate lines 22a and 22b and the storage electrode line 28 and transmits a data voltage. The data lines 62 are formed with first and second source electrodes 65a and 65b extending toward the first and second drain electrodes 66a and 66b, respectively. The data line end 68 is formed at the end of the data line 62 to receive a data signal from another layer or the outside and transmit the data signal to the data line 62. At this time, the data line end 68 is extended in width for connection with an external circuit.

The data line 62, the first and second source electrodes 65a and 65b, and the first and second drain electrodes 66a and 66b may be formed of the same material as the data line of the first embodiment.

The first and second source electrodes 65a and 65b overlap at least a portion of the semiconductor layers 40a and 40b, respectively, and the first and second drain electrodes 66a and 66b respectively form the gate electrodes 26a and 26b. At least a portion of the semiconductor layer 40a and 40b may be overlapped with the first and second source electrodes 65a and 65b. Here, the aforementioned ohmic contact layer is formed between the semiconductor layers 40a and 40b thereunder and between the first and second source electrodes 65a and 65b and the first and second drain electrodes 66a and 66b thereon. It exists in and lowers contact resistance.

The first and second drain electrodes 66a and 66b respectively have a rod-shaped end portion overlapping with the semiconductor layers 40a and 40b, and a drain electrode extension portion 67a having a large area extending therefrom and overlapping with the storage electrode 29. , 67b).

The first and second source electrodes 65a and 65b may be separated into a plurality of branches to surround end portions of the first and second drain electrodes 66a and 66b, respectively, or may be respectively formed by the first and second drain electrodes ( It may be bent to surround the ends of the 66a, 66b).

The passivation layer 70 is formed on the data line 62, the drain electrodes 66a and 66b, and the exposed portions of the semiconductor layers 40a and 40b.

In the passivation layer 70, contact holes 78, 76a, and 76b exposing the data line end 68 and the drain electrode extensions 67a and 67b are formed, respectively. The passivation layer and the gate insulating film have gate line end 24a, respectively. Contact holes 74a and 74b exposing 24b) are formed. First and second pixel electrodes 582a and 582b, which are electrically connected to the first and second drain electrodes 66a and 66b through the contact holes 76a and 76b and positioned in the pixel area, are formed. In addition, the auxiliary gate line ends 86a and 86b and auxiliary data connected to the gate line ends 24a and 24b and the data line end 68 through the contact holes 74a, 74b and 78 on the passivation layer 70, respectively. Line end 88 is formed. Here, the first and second pixel electrodes 582a and 582b and the auxiliary gate and data line ends 86a, 86b and 88 are made of a transparent conductor such as ITO or IZO or a reflective conductor such as aluminum.

The first and second pixel electrodes 582a and 582b are physically and electrically connected to the first and second drain electrodes 66a and 66b through the contact holes 76a and 76b, respectively. Data voltages are applied from 66a and 66b).

One pixel is divided into first and second pixel electrodes 582a and 582b, and the first pixel electrode 582a is a first drain electrode 66a, a first source electrode 65a, and a first gate electrode 22a. ) And the second pixel electrode 582b is driven by a separate thin film transistor composed of a second drain electrode 66b, a second source electrode 65b, and a second gate electrode 22b. .

A pair of gradation voltage sets having different gamma curves obtained from one piece of image information are applied to the first and second pixel electrodes 582a and 582b. The gamma curve for one pixel is a gamma curve obtained by combining them. When determining the pair of gradation voltages, visibility can be improved by ensuring that the composite gamma curve at the front is close to the reference gamma curve at the front and the synthetic gamma curve at the side is closest to the reference gamma curve at the front. have.

As described above, a pixel electrode 582 having a band shape that is bent along the shape of the pixel is formed on the passivation layer 70, and the pixel electrode 582 is formed in a predetermined gap 583 along the data line 62. And a first pixel electrode 582a and a second pixel electrode 582b electrically separated in the vertical direction. Here, the gap 583 divides the pixel region vertically into approximately 1: 2 and partitions the pixel region into the first pixel electrode 582a and the second pixel electrode 582b, and is approximately 45 degrees with the gate lines 22a and 22b. Achieve -45 degrees.

The same trapezoidal fine pattern as described in the first embodiment is formed on the first pixel electrode 582a. For the same reason as described in the first embodiment, the texture is prevented by effectively controlling the movement of the liquid crystal molecules by using the lateral electric field generated by the first pixel electrode 582a having the fine pattern as shown in FIG. 5D. And brightness can be improved. Furthermore, when the raw gray level signal changes from black gray to white gray, the response of the liquid crystal by outputting the corrected gray level signal for pretilt generation and the corrected gray level signal for overshoot generation to the data line 62. Speed can be increased.

In the present exemplary embodiment, a high data voltage may be applied to the first pixel electrode 682a having a fine pattern, and a low data voltage may be applied to the second pixel electrode 682b having no fine pattern, and vice versa. However, in order to improve visibility, it is advantageous to have a large area of the pixel electrode to which a low data voltage is applied. Therefore, a high data voltage is applied to the first pixel electrode 682a and a low data voltage is applied to the second pixel electrode 682b. More preferred. In addition, since the reduction of the aperture ratio due to the fine pattern can be almost neglected at a high voltage, it is advantageous to apply a high data voltage to the first pixel electrode 682a in terms of transmittance.

5B, 5C, and 5D, in the common electrode display panel for a liquid crystal display according to the fourth embodiment of the present invention, the cutout 542 of the common electrode 140 is centered on the second pixel electrode 582b. Are arranged in. That is, the cutout 542 of the common electrode 140 is arranged on the second pixel electrode 582b without the fine pattern.

In this way, the pixel is divided into a plurality of domains by the cutout 542 of the common electrode 140 and the gap 583 of the pixel electrode 582. At this time, the pixel is divided into left and right sides by the cutout 542 and the gap 583, but is divided into six types of domains in which the alignment directions of the liquid crystals are different from each other up and down around the bent portion of the pixel. That is, the pixel is divided into six kinds of domains according to the direction in which the main directors of the liquid crystal molecules included in the liquid crystal layer are arranged when the electric field is applied.

5E is a circuit diagram of a liquid crystal display according to a fourth exemplary embodiment of the present invention.

In FIG. 5E, GLa is the first gate line 22a, GLb is the second gate line 22b, DL is the data line 22, SL is the storage electrode wirings 28 and 29, and PXa is the first. A first subpixel by the pixel electrode 582a is represented, and PXa represents a second subpixel by the second pixel electrode 582b.

The pixel PX includes a pair of subpixels PXa and PXb, and each of the subpixels PXa and PXb is connected to the corresponding gate lines GLa and GLb and the data line DL. And Qb, liquid crystal capacitors Clca and Clcb connected thereto, and storage capacitors Csta and Cstb connected to the switching elements Qa and Qb and the storage electrode line SL. Here, the storage capacitors Csta and Cstb may be omitted as necessary, and in this case, the storage electrode line SL is also unnecessary.

As described above, a pair of gray voltages having different gamma curves obtained from one piece of image information is applied to each of the pair of subpixels PXa and PXb, and a gamma curve of one pixel becomes a gamma curve obtained by combining them. . When determining a pair of gradation voltage sets, visibility can be improved by making the composite gamma curve at the front side closer to the reference gamma curve at the front side and making the composite gamma curve at the side closest to the reference gamma curve at the front side. .

In addition, as described with reference to FIGS. 3A and 3B, in the present exemplary embodiment, fine patterns that are reversed from each other are alternately formed for each pixel, so that the liquid crystal molecules positioned on the thin film transistor array panel are inclined uniformly in four directions on average. Visibility can be implemented.

Hereinafter, the structure of the liquid crystal display according to the fifth embodiment of the present invention will be described in detail with reference to FIG. 6.

6 is a layout view of a liquid crystal display according to a fifth exemplary embodiment of the present invention. For convenience of description, members having the same functions as the members shown in the drawings of the first embodiment are denoted by the same reference numerals, and therefore description thereof is omitted. As shown in FIG. 6, the liquid crystal display of this embodiment has a basically identical structure except for the liquid crystal display of FIGS. 1A to 2D, the cutout 642 of the pixel electrode 682 and the common electrode.

That is, the pixel electrode 682 of the present embodiment includes a first pixel electrode 682a and a second pixel electrode 682b, which are divided left and right by the cutout 642 of the common electrode, although the cutout is not formed. . Here, the first and second pixel electrodes 682a and 682b occupy substantially the same area, and both are composed of a plurality of trapezoidal fine patterns arranged side by side along the data line 62. In addition, the fine pattern of the first pixel electrode 682a and the fine pattern of the second pixel electrode 682b are formed in reverse phase to each other so that the liquid crystal molecules positioned on the thin film transistor array panel are inclined uniformly in four directions on average. Excellent visibility can be achieved.

In this structure, the pixel is divided into a plurality of domains by the cutout 642 of the common electrode. At this time, the pixels are divided into left and right sides by the cutout 642, but are divided into four types of domains in which the alignment directions of the liquid crystals are different from each other up and down around the bent portion of the pixel. That is, the pixel is divided into four types of domains according to the direction in which the main directors of the liquid crystal molecules included in the liquid crystal layer are arranged when the electric field is applied.

As described in the first embodiment, when both the first and second pixel electrodes 682a and 682b are formed in a fine pattern, the movement of the liquid crystal molecules can be effectively controlled by the lateral electric field generated by the fine pattern. Can be. Therefore, even if the width (electrode spacing) W2 of the domain shown in FIG. 6 increases, the movement of the liquid crystal molecules can be effectively controlled. For example, the width W2 of the domain of the liquid crystal display according to the present embodiment may be formed to about 30-60 μm.

Hereinafter, the structure of the liquid crystal display according to the sixth embodiment of the present invention will be described in detail with reference to FIG. 7.

7 is a layout view of a liquid crystal display according to a sixth exemplary embodiment of the present invention. For convenience of description, members having the same functions as the members shown in the drawings of the third embodiment are denoted by the same reference numerals, and therefore description thereof is omitted. As shown in FIG. 7, the liquid crystal display of this embodiment has a basically identical structure except for the liquid crystal display of FIGS. 4A to 4D, the cutout portion 642 of the pixel electrode 782 and the common electrode.

That is, the pixel electrode 782 of the present embodiment includes a first pixel electrode 782a and a second pixel electrode 782b electrically separated up and down by the gap 783. Here, the first and second pixel electrodes 782a and 782b occupy substantially the same area, and both are composed of a plurality of trapezoidal fine patterns arranged side by side along the data line 62. In addition, the fine patterns formed on both sides of the first and second pixel electrodes 782a and 782b are formed in reverse phase to each other, so that the liquid crystal molecules positioned on the thin film transistor array panel are inclined uniformly in four directions on the average so that the visibility is excellent. Can be implemented.

The first pixel electrode 782a is connected to the drain electrode 66 through the contact hole 76. Although the second pixel electrode 782b is in an electrically floating state, the second pixel electrode 782b overlaps the coupling electrode 764 connected to the drain electrode 66 and is capacitively coupled to the first pixel electrode 782a. In other words, the voltage of the second pixel electrode 782b varies depending on the voltage applied to the first pixel electrode 782a.

In this structure, the pixel is divided into a plurality of domains by the cutout 642 of the common electrode. At this time, the pixels are divided into left and right sides by the cutout 642, but are divided into four types of domains in which the alignment directions of the liquid crystals are different from each other up and down around the bent portion of the pixel. That is, the pixel is divided into four types of domains according to the direction in which the main directors of the liquid crystal molecules included in the liquid crystal layer are arranged when the electric field is applied.

As described in the third embodiment, when both the first and second pixel electrodes 782a and 782b are formed in a fine pattern, the movement of the liquid crystal molecules can be effectively controlled by the lateral electric field generated by the fine pattern. Can be. Therefore, even if the width (electrode spacing) W2 of the domain shown in FIG. 7 increases, the movement of the liquid crystal molecules can be effectively controlled. For example, the width W2 of the domain of the liquid crystal display according to the present exemplary embodiment may be formed to about 30-60 μm.

Hereinafter, the structure of the liquid crystal display according to the seventh embodiment of the present invention will be described in detail with reference to FIG. 8.

8 is a layout view of a liquid crystal display according to a seventh exemplary embodiment of the present invention. For convenience of description, members having the same functions as the members shown in the drawings of the fourth embodiment are denoted by the same reference numerals, and therefore description thereof is omitted. As shown in FIG. 8, the liquid crystal display of this embodiment has a basically identical structure except for the liquid crystal display of FIGS. 5A to 5E, the cutout portion 642 of the pixel electrode 882 and the common electrode.

That is, the pixel electrode 882 of the present embodiment includes a first pixel electrode 882a and a second pixel electrode 882b that are electrically separated up and down by the gap 883. Here, the first and second pixel electrodes 882a and 882b occupy almost the same area, and both are composed of a plurality of trapezoidal fine patterns arranged side by side along the data line 62. In addition, the fine patterns formed on both sides of the first and second pixel electrodes 882a and 882b are formed in reverse phase to each other so that the liquid crystal molecules positioned on the thin film transistor array panel are inclined uniformly in four directions on the average, thereby providing excellent visibility. Can be implemented.

A pair of gradation voltage sets having different gamma curves obtained from one piece of image information is applied to the first and second pixel electrodes 882a and 882b. The gamma curve for one pixel is a gamma curve obtained by combining them. When determining the pair of gradation voltages, visibility can be improved by ensuring that the composite gamma curve at the front is close to the reference gamma curve at the front and the synthetic gamma curve at the side is closest to the reference gamma curve at the front. have.

In this structure, the pixel is divided into a plurality of domains by the cutout 642 of the common electrode. At this time, the pixels are divided into left and right sides by the cutout 642, but are divided into four types of domains in which the alignment directions of the liquid crystals are different from each other up and down around the bent portion of the pixel. That is, the pixel is divided into four types of domains according to the direction in which the main directors of the liquid crystal molecules included in the liquid crystal layer are arranged when the electric field is applied.

As described in the fourth embodiment, when both the first and second pixel electrodes 882a and 882b are formed in a fine pattern, the movement of the liquid crystal molecules can be effectively controlled by the lateral electric field generated by the fine pattern. Can be. Therefore, even if the width (electrode spacing) W2 of the domain shown in FIG. 8 increases, the movement of the liquid crystal molecules can be effectively controlled. For example, the width W2 of the domain of the liquid crystal display according to the present exemplary embodiment may be formed to about 30-60 μm.

Although embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

As described above, according to the liquid crystal display according to the present invention, it is possible to improve the luminance and the response speed due to the high aperture ratio.

Claims (55)

A first insulating substrate; A gate line formed on the first insulating substrate and extending in a first direction; A data line formed to insulate and cross the gate line on the first insulating substrate, the data line having a bent portion and a portion extending in a second direction; A pixel electrode formed for each pixel defined by the gate line and the data line crossing each other, and having a sawtooth-shaped fine pattern formed on at least one side along the data line; A thin film transistor connected to the gate line, the data line and the pixel electrode; A second insulating substrate facing the first insulating substrate; A common electrode formed on the second insulating substrate; And And a liquid crystal layer injected between the first insulating substrate and the second insulating substrate. According to claim 1, The pixel electrode includes a first pixel electrode and a second pixel electrode which are vertically divided by 1: 2 along the data line by a first domain dividing unit, and the fine pattern is formed on the first pixel electrode. Liquid crystal display. The method of claim 2, And the common electrode is divided along the data line by second domain dividing means, and the second domain dividing means is positioned on the second pixel electrode. The method of claim 3, wherein And the first and second domain dividing means are cutouts or protrusions. The method of claim 2, The pixel is divided into six kinds of domains according to a direction in which the main directors of the liquid crystals included in the liquid crystal layer are arranged when an electric field is applied. The method of claim 5, The width of the domain is about 20-40㎛ liquid crystal display device. According to claim 1, The pixel electrode has the fine pattern formed on both sides along the data line. The method of claim 8, The fine patterns formed on both sides of the pixel electrode are formed in reverse phase to each other. The method of claim 8, And the common electrode is divided along the data line by second domain dividing means, and the second domain dividing means is positioned above the center of the pixel electrode. The method of claim 9, The second domain dividing means is a cutout or a protrusion. The method of claim 8, The pixel is divided into four types of domains according to a direction in which the main directors of the liquid crystal included in the liquid crystal layer are arranged when an electric field is applied. The method of claim 11, wherein Wherein the domain has a width of about 30-60 μm. According to claim 1, The fine pattern has a trapezoidal shape.  The method of claim 13, The upper side of the trapezoidal fine pattern is about 1-8㎛, the lower side is about 1-15㎛ the liquid crystal display device. According to claim 1, And a fine pattern inversely opposite to the fine pattern in a neighboring pixel adjacent to the pixel. According to claim 1, The liquid crystal contained in the liquid crystal layer has negative dielectric anisotropy, and the liquid crystal has a long axis perpendicular to the first and second insulating substrates. According to claim 1, The curved portion of the data line includes two straight portions, one of the two straight portions substantially 45 degrees with respect to the gate line, and the other one substantially -45 degrees with respect to the gate line. Device. According to claim 1, And a correction gradation signal for generating a pretilt and a correction gradation signal for generating an overshoot to the data line when the gradation signal is changed from black gradation to white gradation. A first insulating substrate; A gate line formed on the first insulating substrate and extending in a first direction; A data line formed to insulate and cross the gate line on the first insulating substrate, the data line having a bent portion and a portion extending in a second direction; A first pixel electrode formed for each pixel defined by the gate line and the data line crossing each other, and having a sawtooth fine pattern formed thereon; A second pixel electrode formed for each of the pixels and capacitively coupled to the first pixel electrode; A thin film transistor connected to the gate line and the data line and connected to any one of the first and second pixel electrodes; A second insulating substrate facing the first insulating substrate; A common electrode formed on the second insulating substrate; And And a liquid crystal layer injected between the first insulating substrate and the second insulating substrate. The method of claim 19, And the first and second pixel electrodes are vertically divided substantially 1: 2 along the data line, and the thin film transistor is connected to the first pixel electrode. The method of claim 20, And the common electrode is divided along the data line by second domain dividing means, and the second domain dividing means is positioned on the second pixel electrode. The method of claim 21, The second domain dividing means is a cutout or a protrusion. The method of claim 20, The pixel is divided into six kinds of domains according to a direction in which the main directors of the liquid crystals included in the liquid crystal layer are arranged when an electric field is applied. The method of claim 23, wherein The width of the domain is about 20-40㎛ liquid crystal display device. The method of claim 19, And the first and second pixel electrodes are vertically divided substantially vertically along the data line, and the second pixel electrode is formed with a sawtooth-shaped fine pattern. The method of claim 25, The fine patterns formed on the first and second pixel electrodes, respectively, are formed in reverse phase to each other. The method of claim 25, And the common electrode is divided along the data line by second domain dividing means, and the second domain dividing means is positioned between the first and second pixel electrodes. The method of claim 27, The second domain dividing means is a cutout or a protrusion. The method of claim 25, The pixel is divided into four types of domains according to a direction in which the main directors of the liquid crystal included in the liquid crystal layer are arranged when an electric field is applied. The method of claim 29, Wherein the domain has a width of about 30-60 μm. The method of claim 19, The fine pattern has a trapezoidal shape. The method of claim 31, wherein The upper side of the trapezoidal fine pattern is about 1-8㎛, the lower side is about 1-15㎛ the liquid crystal display device. The method of claim 19, And a fine pattern inversely opposite to the fine pattern in a neighboring pixel adjacent to the pixel. The method of claim 19, The liquid crystal contained in the liquid crystal layer has negative dielectric anisotropy, and the liquid crystal has a long axis perpendicular to the first and second insulating substrates. The method of claim 19, The curved portion of the data line includes two straight portions, one of the two straight portions substantially 45 degrees with respect to the gate line, and the other one substantially -45 degrees with respect to the gate line. Device. The method of claim 19, And a correction gradation signal for generating a pretilt and a correction gradation signal for generating an overshoot to the data line when the gradation signal is changed from black gradation to white gradation. A first insulating substrate; First and second gate lines extending in a first direction on the first insulating substrate; A data line formed on the first insulating substrate to insulate and cross the first and second gate lines, the data line having a curved portion and a portion extending in a second direction; First and second pixel electrodes formed for each pixel defined by the intersection of the first and second gate lines and the data line, the first and second pixel electrodes having a sawtooth-shaped fine pattern formed on the first pixel electrode; A first thin film transistor connected to the first gate line, the first pixel electrode, and the data electrode; A second thin film transistor connected to the second gate line, the second pixel electrode, and the data electrode; A second insulating substrate facing the first insulating substrate; A common electrode formed on the second insulating substrate; And And a liquid crystal layer injected between the first insulating substrate and the second insulating substrate. The method of claim 37, And a different data voltage obtained from one image information is applied to the first pixel electrode and the second pixel electrode, and a data voltage relatively higher than the second pixel electrode is applied to the first pixel electrode. The method of claim 37, And the first and second pixel electrodes are vertically divided by 1: 2 along the data line. The method of claim 39, And the common electrode is divided along the data line by second domain dividing means, and the second domain dividing means is positioned on the second pixel electrode. 41. The method of claim 40 wherein The second domain dividing means is a cutout or a protrusion. The method of claim 39, The pixel is divided into six kinds of domains according to a direction in which the main directors of the liquid crystals included in the liquid crystal layer are arranged when an electric field is applied. The method of claim 42, wherein The width of the domain is about 20-40㎛ liquid crystal display device. The method of claim 37, And the first and second pixel electrodes are vertically divided substantially vertically along the data line, and the second pixel electrode is formed with a sawtooth-shaped fine pattern. The method of claim 44, The fine patterns formed on the first and second pixel electrodes, respectively, are formed in reverse phase to each other. The method of claim 44, And the common electrode is divided along the data line by second domain dividing means, and the second domain dividing means is positioned between the first and second pixel electrodes. 47. The method of claim 46 wherein The second domain dividing means is a cutout or a protrusion. The method of claim 44, The pixel is divided into four types of domains according to a direction in which the main directors of the liquid crystal included in the liquid crystal layer are arranged when an electric field is applied. 49. The method of claim 48 wherein Wherein the domain has a width of about 30-60 μm. The method of claim 37, The fine pattern has a trapezoidal shape. 51. The method of claim 50, The upper side of the trapezoidal fine pattern is about 1-8㎛, the lower side is about 1-15㎛ the liquid crystal display device. The method of claim 37, And a fine pattern inversely opposite to the fine pattern in a neighboring pixel adjacent to the pixel. The method of claim 37, The liquid crystal contained in the liquid crystal layer has negative dielectric anisotropy, and the liquid crystal has a long axis perpendicular to the first and second insulating substrates.  The method of claim 37, The curved portion of the data line includes two straight portions, one of the two straight portions substantially 45 degrees with respect to the gate line, and the other one substantially -45 degrees with respect to the gate line. Device. The method of claim 37, And a correction gradation signal for generating a pretilt and a correction gradation signal for generating an overshoot to the data line when the gradation signal is changed from black gradation to white gradation.

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