KR100853780B1 - Liquid crystal display device of in-plane switching - Google Patents

Abstract

To provide a liquid crystal display device having a transverse electric field system (IPS) suitable for improving fairness, price competitiveness and aperture ratio, the liquid crystal display device of the IPS of the present invention for achieving the above object is arranged on the lower substrate A plurality of gate lines and data lines defining a pixel area; A thin film transistor formed at an intersection of the gate line and the data line; A plurality of first common electrodes formed in a direction parallel to the gate line; A second common electrode spaced apart from the first common electrode by a predetermined distance and connected to a pixel area adjacent to the horizontal area in a central portion of the pixel area; A third common electrode spaced apart from each other in a direction parallel to the data line and formed to connect the first and second common electrodes to each other; A first pixel electrode formed between the first and second common electrodes in a direction parallel to the gate line; Second pixel electrodes formed to connect the first pixel electrodes to both ends of the first pixel electrode; A color filter layer formed on the upper substrate; A black matrix formed on the upper substrate so as to correspond to an intersection of the gate line, the thin film transistor, and the data line and the second common electrode; And a liquid crystal layer formed between the upper and lower substrates, and an alignment layer.

Black Matrix, IPS, Loving, Electric Field

Description

Transverse electric field type liquid crystal display device {LIQUID CRYSTAL DISPLAY DEVICE OF IN-PLANE SWITCHING}

1 is an exploded perspective view showing a part of a typical TN liquid crystal display device

Figure 2 is a schematic cross-sectional view showing a liquid crystal display of a general IPS

3A to 3B are diagrams illustrating phase transitions of liquid crystals when voltage on / off is performed in IPS mode.

4A and 4B are perspective views showing the operation of the IPS mode LCD in the off and on states, respectively.

5 is a plan view showing a liquid crystal display of a conventional IPS

6 is a plan view showing a black matrix layer formed on a conventional upper substrate

7A, 7B, and 8 are plan views of a liquid crystal display of IPS and a black matrix according to the first embodiment of the present invention.

9 and 10 are plan views of a liquid crystal display of IPS and a black matrix according to the second embodiment of the present invention.

11 is an enlarged plan view of a portion 'A' of FIGS. 9 and 10.

Explanation of symbols on the main parts of the drawings

71 and 81: gate lines 72 and 82: data lines                 

72a, 82a: source electrode 72b, 82b: drain electrode

73 and 83: active layers 74a and 84a: first common electrode

74b, 84b: second common electrode 74c, 84c: third common electrode

75a, 85a: first pixel electrode 75b, 85b: second pixel electrode

75c: third pixel electrode 76, 86: black matrix

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and in particular, an in-plane switching (hereinafter referred to as IPS) suitable for improving fairness, securing price competitiveness, and improving aperture ratio to increase luminance. The present invention relates to a liquid crystal display device.

As the information society develops, the demand for display devices is increasing in various forms.In recent years, liquid crystal display (LCD), plasma display panel (PDP), electro luminescent display (ELD), and vacuum fluorescent display (VFD) have been developed. Various flat panel display devices have been studied, and some are already used as display devices in various devices.

Among them, LCD is the most widely used as a substitute for CRT (Cathode Ray Tube) for the use of mobile image display device because of the excellent image quality, light weight, thinness, and low power consumption, and mobile type such as monitor of notebook computer. In addition, it has been variously developed such as a television for receiving and displaying a room transmission call and a monitor of a computer.

As described above, although various technical advances have been made in order for the liquid crystal display device to serve as a screen display device in various fields, the task of improving the image quality as the screen display device has many advantages and disadvantages.

Therefore, in order to use a liquid crystal display device in various parts as a general screen display device, the key to development is how much high definition images such as high definition, high brightness, and large area can be realized while maintaining the characteristics of light weight, thinness, and low power consumption. It can be said.

Such a liquid crystal display device may be broadly divided into a liquid crystal panel displaying an image and a driving unit for applying a driving signal to the liquid crystal panel, wherein the liquid crystal panel includes first and second glass substrates having a space and are bonded to each other; It consists of a liquid crystal layer injected between the said 1st, 2nd glass substrate.

The first glass substrate (TFT array substrate) may include a plurality of gate lines arranged in one direction at a predetermined interval, a plurality of data lines arranged at regular intervals in a direction perpendicular to the gate lines, and A plurality of pixel electrodes formed in a matrix form in each pixel region defined by crossing each gate line and data line, and a plurality of thin films that transmit signals of the data line to each pixel electrode by being switched by signals of the gate line The transistor is formed.

In addition, the second glass substrate (color filter substrate) includes a black matrix layer for blocking light except for the pixel region, an R, G, and B color filter layer for expressing color colors, and a common electrode for implementing an image. Is formed. Of course, the common electrode is formed on the first glass substrate in the transverse electric field type liquid crystal display device.

The first and second glass substrates are bonded by an actual material having a predetermined space and a liquid crystal injection hole by a spacer, and a liquid crystal is injected between the two substrates.

In this case, in the liquid crystal injection method, the liquid crystal is injected between the two substrates by osmotic pressure when the liquid crystal injection hole is immersed in the liquid crystal container by maintaining the vacuum state between the two substrates bonded by the reality. When the liquid crystal is injected as described above, the liquid crystal injection hole is sealed with a sealing material.

On the other hand, the driving principle of the liquid crystal display device as described above uses the optical anisotropy and polarization of the liquid crystal.

Since the liquid crystal is thin and long in structure, the liquid crystal has a direction in the arrangement of molecules, and the liquid crystal may be artificially applied to control the direction of the molecular arrangement.

Accordingly, when the molecular arrangement direction of the liquid crystal is arbitrarily adjusted, the molecular arrangement of the liquid crystal is changed, and light polarized by optical anisotropy may be arbitrarily modulated to express image information.

Such liquid crystals may be classified into positive liquid crystals having a positive dielectric anisotropy and negative liquid crystals having a negative dielectric anisotropy according to an electrical specific classification, and liquid crystal molecules having a positive dielectric anisotropy are long axes of liquid crystal molecules in a direction in which an electric field is applied. The liquid crystal molecules arranged in parallel and having negative dielectric anisotropy are arranged perpendicularly to the direction in which the electric field is applied and the major axis of the liquid crystal molecules.

1 is an exploded perspective view illustrating a part of a general TN liquid crystal display device.

As shown in FIG. 1, the lower substrate 1 and the upper substrate 2 bonded to each other with a predetermined space, and the liquid crystal layer 3 injected between the lower substrate 1 and the upper substrate 2 are composed of. It is.

More specifically, the lower substrate 1 has a plurality of gate lines 4 arranged in one direction at regular intervals to define the pixel region P, and in a direction perpendicular to the gate lines 4. A plurality of data lines 5 are arranged at regular intervals, and a pixel electrode 6 is formed in each pixel region P where the gate line 4 and the data line 5 intersect, and each gate line The thin film transistor T is formed at the portion where (4) and the data line 5 intersect.

The upper substrate 2 includes a black matrix layer 7 for blocking light in portions other than the pixel region P, an R, G, and B color filter layer 8 for expressing color colors, and an image. The common electrode 9 is formed to implement the.

The thin film transistor T may include a gate electrode protruding from the gate line 4, a gate insulating film (not shown) formed on the front surface, an active layer formed on the gate insulating film above the gate electrode, and the data. And a source electrode protruding from the line 5 and a drain electrode to face the source electrode.                         

The pixel electrode 6 uses a transparent conductive metal having a relatively high light transmittance, such as indium-tin-oxide (ITO).

In the liquid crystal display device configured as described above, the liquid crystal layer 3 positioned on the pixel electrode 6 is aligned by a signal applied from the thin film transistor T, and the liquid crystal layer 3 is aligned with the alignment degree of the liquid crystal layer 3. Accordingly, the image can be expressed by controlling the amount of light passing through the liquid crystal layer 3.

As described above, the liquid crystal panel drives the liquid crystal by an electric field applied up and down, and has excellent characteristics such as transmittance and aperture ratio, and the common electrode 9 of the upper substrate 2 serves as a ground to discharge static electricity. It is possible to prevent the destruction of the liquid crystal cell.

However, the liquid crystal drive by the electric field applied up-down has a disadvantage that the viewing angle characteristics are not excellent.

Accordingly, in order to overcome the above disadvantages, a new technology, namely, a liquid crystal display device of IPS, has been proposed.

2 is a schematic cross-sectional view showing a liquid crystal display of a general IPS.

As shown in FIG. 2, the pixel electrode 12 and the common electrode 13 are formed on the lower substrate 11 on the same plane.

In addition, the liquid crystal layer 14 formed between the lower substrate 11 and the upper substrate 15 bonded to the lower substrate 11 may be disposed between the pixel electrode 12 and the common electrode 13 on the lower substrate 11. It works by electric field.

3A to 3B are diagrams illustrating phase transitions of liquid crystals when voltages are turned on and off in the IPS mode.

That is, FIG. 3A shows an off state in which no transverse electric field is applied to the pixel electrode 12 or the common electrode 13, so that the phase change of the liquid crystal layer 14 does not occur. For example, the pixel electrode 12 and the common electrode 13 are basically shifted by 45 ° in the horizontal direction.

FIG. 3B is an on state in which a transverse electric field is applied to the pixel electrode 12 and the common electrode 13, and a phase shift of the liquid crystal layer 14 occurs, and is about 45 ° compared to the off state of FIG. 3A. It can be seen that the horizontal direction of the pixel electrode 12 and the common electrode 13 and the twist direction of the liquid crystal have a twist angle.

As described above, in the liquid crystal display of the IPS, both the pixel electrode 12 and the common electrode 13 exist on the same plane.

An advantage of the transverse electric field method is that a wide viewing angle is possible. That is, when the liquid crystal display device is viewed from the front, the liquid crystal display device may be visible in the about 70 ° direction in the up / down / left / right directions.

In addition, there is an advantage that the manufacturing process is simpler and the color shift according to the viewing angle is smaller than that of the liquid crystal display device.

However, since the common electrode 13 and the pixel electrode 12 exist on the same plane, there is a disadvantage in that transmittance and aperture ratio due to light are reduced.

In addition, there is a disadvantage in that the response time due to the driving voltage must be improved and the cell gap is made uniform because the misalign margin of the cell gap is small.                         

That is, the transverse electric field type liquid crystal display device has the advantages and disadvantages as described above can be selected according to the user's use.

4A and 4B are perspective views showing the operation of the liquid crystal display of the IPS in the off state and the on state, respectively.

As shown in FIG. 4A, when no voltage is applied to the pixel electrode 12 or the common electrode 13, the liquid crystal molecules array direction 16 is arranged in the same direction as that of the initial alignment layer (not shown). do.

As shown in FIG. 4B, when the voltage is applied to the pixel electrode 12 and the common electrode 13, the alignment direction 16 of the liquid crystal molecules is arranged in the direction 17 in which the electric field is applied. .

Hereinafter, a liquid crystal display of a conventional IPS will be described with reference to the accompanying drawings.

FIG. 5 is a plan view showing a liquid crystal display of a conventional IPS, and FIG. 6 is a plan view showing a black matrix layer formed on a conventional upper substrate.

In the conventional liquid crystal display of the IPS, as shown in FIGS. 5 and 6, the lower substrate (TFT substrate) includes a gate line, a data line, a thin film transistor, a common electrode, and a pixel electrode, and an upper substrate (color filter substrate). ) Is composed of R, G and B color filter layers and a black matrix. More detailed configuration is as follows.

In order to define a pixel area on the transparent lower substrate, a plurality of gate lines 51 are arranged in one direction at regular intervals, and a plurality of data lines 52 at regular intervals in a direction perpendicular to the gate line 51. ) Is arranged.

A plurality of thin film transistors TFT is formed in each pixel area defined by the gate line 51 and the data line 52 crossing each other.

The thin film transistor TFT may include a gate electrode defined in one region of the gate line 51, a gate insulating film (not shown) formed on an entire surface thereof, and an active layer 53 formed on the gate insulating film above the gate electrode. ) And a drain electrode 52b protruding from the data line 52 and extending from the source electrode 52a formed on the active layer 53 and connected to the pixel electrode at regular intervals from the source electrode 52a. It consists of.

The common electrode is formed in the pixel region and the neighboring pixel region defined by the gate line 51 and the data line 52 intersecting, and extends to the neighboring pixel region in a direction parallel to the gate line 51. A plurality of second common electrodes 54b formed to be spaced apart from each other between the first common electrodes 54a, the first common electrodes 54a, and a direction parallel to and adjacent to the data line 52 The first and second common electrodes 54a and 54b are connected to each other, and the plurality of third common electrodes 54c are formed to be spaced apart from the data line 52 by a predetermined distance.

At this time, the second common electrodes 54b have a 'V' shape.

The pixel electrode is formed on the same layer as the data line 52 in the pixel area defined by the gate line 51 and the data line 52 intersecting, and is adjacent to the gate line 51. The first pixel electrodes 55a formed in parallel directions, the second pixel electrodes 55b formed in parallel with the second common electrodes 54b in a 'V' shape, and the first pixel electrodes 55a formed in parallel to each other. The first and second pixel electrodes 55a and 55b are connected to each other, and the third pixel electrodes 55c are formed to be spaced apart from the data line 52 by a predetermined distance.

At this time, the portion adjacent to the TFT of the third pixel electrode 55c is extended to be connected to the drain electrode 52b.

A first insulating film is interposed between the common electrode and the pixel electrode. (Not shown)

As shown in FIG. 6, the upper substrate corresponding to the lower substrate configured as described above serves to distinguish between the color filter layer (not shown) and the color filter layer formed in a portion corresponding to the pixel region to realize color, and to block light. It consists of a black matrix 56 formed to

In this case, as illustrated in FIG. 6, the black matrix 56 is formed in a portion corresponding to the peripheral region including the gate line 51 and the data line 52 and the TFT region.

If the black matrix 56 is formed as described above, the process is complicated because the lower substrate bonding margin must be designed in the process.

In addition, the conventional black matrix 56 is formed using a resin in consideration of the problem of vertical crosstalk between the data line, the black matrix, and the pixel electrode, which is disadvantageous in terms of fairness and cost than when forming a black matrix using metal. .

The present invention has been made to solve the above problems, and an object of the present invention is to provide a liquid crystal display device of a transverse electric field system (IPS) suitable for improving the fairness, price competitiveness and aperture ratio.

The liquid crystal display of the IPS of the present invention for achieving the above object comprises a plurality of gate lines and data lines arranged on the lower substrate to define a pixel region; A thin film transistor formed at an intersection of the gate line and the data line; A plurality of first common electrodes formed in a direction parallel to the gate line; A second common electrode spaced apart from the first common electrode by a predetermined distance and connected to a pixel area adjacent to the horizontal area in the center of the pixel area; A third common electrode spaced apart from each other in a direction parallel to the data line and formed to connect the first and second common electrodes to each other; A first pixel electrode formed between the first and second common electrodes in a direction parallel to the gate line; Second pixel electrodes formed to connect the first pixel electrodes to both ends of the first pixel electrode; A color filter layer formed on the upper substrate; A black matrix formed on the upper substrate so as to correspond to an intersection of the gate line, the thin film transistor, and the data line and the second common electrode; And a liquid crystal layer formed between the upper and lower substrates, and an alignment layer.

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The first to third common electrodes are formed on the same layer as the gate line in the pixel region and the neighboring pixel region.

The first and second pixel electrodes are formed on the same layer as the data line in a pixel area defined by the gate line and the data line crossing each other.

The black matrix may be formed of a resin or a metal.

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The black matrix is formed at a portion where the second common electrodes and the data line cross the gate line and the thin film transistor.

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The thin film transistor may include a gate electrode defined in one region of the gate line, a gate insulating film formed on an entire surface of the lower substrate, an active layer formed on the gate insulating film above the gate electrode, and protrude from the data line. A source electrode overlapped with the layer, and a drain electrode extending and connected to the second pixel electrode at regular intervals from the source electrode.

An insulating film formed of any one of acryl, polyimide, BCB, oxide film, and nitride film is interposed between the first to third common electrode and the first and second pixel electrodes.

Hereinafter, a liquid crystal display of an IPS according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

The present invention relates to an IPS liquid crystal display device in which rubbing is in a horizontal direction, and changes the black matrix (BM) structure in the region between the common electrode and the data line when the electric field direction and the rubbing direction are parallel.

Hereinafter, description will be given for each embodiment.

First embodiment

7A, 7B, and 8 are plan views of a liquid crystal display of IPS and a black matrix according to the first embodiment of the present invention.

In the first embodiment of the present invention, in a liquid crystal display of an IPS in which rubbing is in a horizontal direction, a common electrode (a common electrode formed at an upper side and a lower side in a pixel region) adjacent to a gate line of a lower substrate extends to a neighboring pixel region. When formed, it corresponds to the structure of the black matrix of the upper substrate corresponding thereto.

In the liquid crystal display of the IPS according to the first embodiment of the present invention, as shown in FIGS. 7A and 8, the transparent lower substrate (TFT substrate) includes a gate line, a data line, a thin film transistor, a common electrode, and a pixel electrode. The upper substrate (color filter substrate) is composed of color filter layers of R, G, and B, and a black matrix. More detailed configuration is as follows.

In order to define a pixel area on the transparent lower substrate, a plurality of gate lines 71 are arranged in one direction at regular intervals, and a plurality of data lines 72 at regular intervals in a direction perpendicular to the gate line 71. Is arranged.

A plurality of TFTs are formed in each pixel area defined by the gate line 71 and the data line 72 crossing each other.

The thin film transistor TFT may include a gate electrode defined in one region of the gate line 71, a gate insulating film (not shown) formed on an entire surface thereof, and an active layer 73 formed on the gate insulating film above the gate electrode. ), A source electrode 72a protruding from the data line 72 and formed on the active layer 73, and a drain electrode 72b extending and connected to the pixel electrode at regular intervals from the source electrode 72a. It is composed of

In this case, the TFT may be configured to have a general TFT structure as shown in FIG. 7B.                     

That is, a gate electrode protruding on one side of the gate line having one direction, a gate insulating film (not shown) formed on the front surface of the lower substrate, an active layer 73 formed on the gate insulating film above the gate electrode, and a gate electrode A source electrode 72a formed to protrude from the data line so as to overlap the upper portion of one side, and a drain electrode that is separated from the source electrode 72a at a predetermined interval so as to overlap the upper portion of the gate electrode and is connected to the pixel electrode and extends It can also be configured as 72b.

The common electrode is formed on the same layer as the gate line 71 in a pixel region where the gate line 71 and the data line 72 cross and a neighboring pixel region, and is adjacent to the gate line 71. First common electrodes 74a formed to extend to neighboring pixel regions in parallel directions, a plurality of second common electrodes 74b formed to be spaced apart from each other between the first common electrodes 74a, and A plurality of third common electrodes 74c formed to connect the first and second common electrodes 74a and 74b to each other in a parallel direction adjacent to the data line 72 and to be spaced apart from the data line 72 by a predetermined distance. )

At this time, the second common electrodes 74b have a 'V' shape.

The pixel electrode is formed on the same layer as the data line 72 in the pixel area defined by the gate line 71 and the data line 72 intersecting, and is adjacent to the gate line 71. The first pixel electrodes 75a formed in parallel directions, the second pixel electrodes 75b formed in parallel with the second common electrodes 74b in a 'V' shape, and the first pixels The second pixel electrodes 75a and 75b are connected to each other, and the third pixel electrodes 75c are formed to be spaced apart from the data line 72 by a predetermined distance.                     

At this time, the portion adjacent to the TFT of the third pixel electrode 75c is extended to be connected to the drain electrode 72b.

A first insulating film made of any one of acryl, polyimide, BCB, oxide film, and nitride film is interposed between the common electrode and the pixel electrode.

In the above description, the second common electrodes 74b and the second pixel electrode 75b may be formed in an inverted 'V' shape or may have an inclined diagonal shape.

As illustrated in FIG. 8, the upper substrate corresponding to the lower substrate configured as described above serves to distinguish between the color filter layer (not shown) and the color filter layer formed in a portion corresponding to the pixel region to realize color. It consists of a black matrix 76 formed to

In this case, the black matrix 76 is typically formed in a portion corresponding to the gate line, the data line, and the TFT region to prevent light leakage. However, as in the present invention, the liquid crystal display of the IPS is rubbed in the horizontal direction. Since the electric field direction has a direction parallel to the rubbing direction between the data line 72 and the outermost common electrode, that is, the third common electrode 74c, there is no light leakage phenomenon and thus it is not necessary to form the black matrix 76. .

That is, since the liquid crystal rotation is no longer between the data line 72 and the third common electrode 74c, no matter how strong the electric field is, there is no need to prevent leakage of light using the black matrix 76. Most of 72) need not be covered with black matrix 76. The region which does not need to be covered with the black matrix is called a black matrix free region.

Meanwhile, the black matrix 76 is formed in a region corresponding to the data line 72 that intersects the first common electrode 74a that extends to the neighboring pixel region in addition to the gate line and the TFT region. This is to prevent light leakage caused by an electric field that is not horizontally interposed between the first common electrode 74a and the data line 72 extending in the pixel region.

In other words, the black matrix 76 is further provided in regions corresponding to the upper and lower portions of the common electrode extending from the region corresponding to the pixel region to the neighboring pixel region.

In general, in the IPS liquid crystal display device, the black matrix 76 is formed on the upper substrate by using a resin, because when the black matrix is formed of a metal, the coupling between the data line, the black matrix, and the pixel electrode is performed. This is because vertical crosstalk occurs.

The present invention can be formed using a resin as described above.

In addition, since vertical crosstalk does not occur in the black matrix free region in the present invention, the black matrix 76 in the gate line and the TFT region can be formed using metal instead of resin.

Thus, when the black matrix 76 is formed using a metal, the pattern is easier than when using a resin, which is advantageous in terms of productivity and cost.

In the case of forming the resin or the metal, the upper and lower substrate bonding margins do not need to be considered toward the data line, thereby improving the aperture ratio.                     

In addition, light leakage blocking of the gate line (including the gate electrode) may be achieved by forming a color filter layer of R, G, and B in addition to the black matrix.

In the liquid crystal display of the IPS configured as described above, the liquid crystal positioned between the common electrode 29 and the pixel electrode 28 is disposed in the same direction by a transverse electric field in which the liquid crystal is distributed between the common electrode 29 and the pixel electrode 28. Arranged in a single domain, and in the transverse electric field system, a plurality of multi-domains can be configured in a single pixel area, and thus a liquid crystal display having a wider viewing angle can be manufactured.

The first embodiment of the present invention is applicable to a structure in which the data line and the common electrode overlap, and do not form a black matrix on the data line except for a portion where the common electrode extending to the neighboring pixel region and the data line intersect. You don't have to.

Second embodiment

9 and 10 are plan views of an IPS liquid crystal display and a black matrix according to a second embodiment of the present invention, and FIG. 11 is an enlarged plan view of a portion 'A'.

According to the second embodiment of the present invention, in the IPS liquid crystal display device in which rubbing is in a horizontal direction, an upper portion corresponding to a common electrode formed at an intermediate portion of a pixel region of the lower substrate is extended to a neighboring pixel region. It is about the structure of the black matrix of the substrate.

In the liquid crystal display of the IPS according to the second embodiment of the present invention, as shown in FIGS. 9, 10, and 11, the transparent lower substrate (TFT substrate) includes a gate line, a data line, a thin film transistor, a common electrode, and a pixel electrode. The upper substrate (color filter substrate) is composed of R, G, B color filter layers, and a black matrix (Black Matrix), a more detailed configuration is as follows.

In order to define a pixel area on the transparent lower substrate, a plurality of gate lines 81 are arranged in one direction at regular intervals, and a plurality of data lines 82 at regular intervals in a direction perpendicular to the gate line 81. Is arranged.

A plurality of thin film transistors TFT is formed in each pixel area defined by the gate line 81 and the data line 82 crossing each other.

The thin film transistor TFT may include a gate electrode defined in one region of the gate line 81, a gate insulating film (not shown) formed on an entire surface thereof, and an active layer 83 formed on the gate insulating film above the gate electrode. And a source electrode 82a protruding from the data line 82 and a drain electrode 82b formed to be connected to the pixel electrode at regular intervals from the source electrode 82a formed on the active layer 83 and connected to the pixel electrode. It is composed.

In this case, the TFT may be configured to have a general TFT structure as in the TFT of FIG. 7B.

That is, a gate electrode protruding on one side of the gate line having one direction, a gate insulating film formed on the front surface of the lower substrate, an active layer formed on the gate insulating film on the upper side of the gate electrode, and the data line so as to overlap the upper side of the gate electrode A source electrode may be formed to protrude from the source electrode, and a drain electrode separated from the source electrode at a predetermined interval so as to overlap the upper portion of the gate electrode and connected to the pixel electrode.

The common electrode is formed on the same layer as the gate line 81 in the pixel region defined by the gate line 81 and the data line 82 intersecting and in the neighboring pixel region.

The common electrode is a plurality of first common electrodes 84a formed in a direction parallel to the gate line 81 and a pixel region adjacent to a central portion of the pixel region spaced apart from the first common electrode 84a by a predetermined distance. The extended second common electrode 84b and the first and second common electrodes 84a and 84b are connected to each other in a direction parallel to the data line 82 and are spaced apart from the data line 82 at a predetermined interval. It is composed of a plurality of third common electrodes 84c spaced apart.

At this time, the first and second common electrodes 84a and 84b are formed in parallel in one direction.

The pixel electrode is formed on the same layer as the data line 82 in a pixel area defined by the gate line 81 and the data line 82 intersecting each other.

The pixel electrode may include the first pixel electrodes 85a and the first pixel electrodes 85a formed between the first and second common electrodes 84a and 84b in a direction parallel to the gate line 81. The second pixel electrodes 85b are formed at both ends of the first pixel electrode 85a to be spaced apart from the data line 82 so as to be connected to each other.

At this time, a portion of the second pixel electrode 85b adjacent to the TFT extends to be connected to the drain electrode 82b.

A first insulating film made of any one of acryl, polyimide, BCB, oxide film, and nitride film is interposed between the common electrode and the pixel electrode.

In the above description, the first and second common electrodes 84a and 84b and the first pixel electrode 85a may be formed in an inverted 'V' shape or may be formed in a diagonal shape having a slope.

The upper substrate corresponding to the lower substrate configured as described above has a color filter layer (not shown) formed in a portion corresponding to the pixel region to realize color as shown in FIGS. 10 and 11, and separation and light between the color filter layers. It consists of a black matrix 86 formed to serve as a blocking role.

In this case, the black matrix 86 is generally formed in a portion corresponding to the gate line, the data line, and the TFT region to prevent light leakage. However, as in the present invention, the IPS liquid crystal display device is rubbed in the horizontal direction. In the embodiment, since the electric field direction has a direction parallel to the rubbing direction between the data line 82 and the outermost common electrode, that is, the third common electrode 84c, the black matrix 86 does not need to be formed.

That is, since the liquid crystal rotation is no longer between the data line 82 and the third common electrode 84c, no matter how strong the electric field is, there is no need to prevent the leakage of light using the black matrix 86. It is not necessary to cover most of 82 with the black matrix 86. Thus, the area | region which does not need to cover with a black matrix is called a black matrix free area | region.

Meanwhile, the black matrix 86 extends to the neighboring pixel region across the lower portion of the data line 82 in addition to the gate line and the TFT region, as shown in FIG. The second common electrode 84b is formed in the intersecting data line 82 and regions corresponding to both sides of the second common electrode 84b, because the second common electrode 84b and the data line 82 extend to neighboring pixel regions. This is to prevent light leakage caused by an electric field that is not horizontally applied to the liver.

In other words, the black matrix 86 is further provided in the region corresponding to the intersection of the second common electrode 84b and the data line 82 extending from the region corresponding to the pixel region to the neighboring pixel region.

Also, in the liquid crystal display of the IPS according to the second embodiment of the present invention, the black matrix 86 can be formed using resin or metal as in the first embodiment, and the effect is the same.

In addition, light leakage blocking of the gate line (including the gate electrode) may be achieved by forming a color filter layer of R, G, and B in addition to the black matrix.

As described above, in the second embodiment of the present invention, the black matrix 86 is formed only at the portion where the common electrode and the data line intersect the gate line, the TFT region, and the neighboring pixel region, and the region adjacent thereto. It does not need to be formed in other data lines.

The second embodiment of the present invention can also be applied to a structure in which the data line and the common electrode overlap, and in this case, the remaining data except for a portion where the common electrode extending to the neighboring pixel area and the data line intersect and an area adjacent thereto are crossed. It is not necessary to form a black matrix in the line.

On the other hand, the present invention described above is not limited to the above-described embodiment and the accompanying drawings, it is possible that various substitutions, modifications and changes within the scope without departing from the technical spirit of the present invention. It will be apparent to those of ordinary skill in Esau.

The liquid crystal display of the transverse electric field system (IPS) of the present invention as described above has the following effects.

First, since a black matrix can be formed using a metal instead of a resin, the pattern is easier than using a resin, which is advantageous in terms of productivity and cost.

Second, since the upper and lower substrate bonding margins need not be considered toward the data line, the aperture ratio can be improved and the luminance can be increased.

Claims (16)

A plurality of gate lines and data lines intersecting the lower substrate to define a pixel area; A thin film transistor formed at an intersection of the gate line and the data line; A plurality of first common electrodes formed in a direction parallel to the gate line; A second common electrode spaced apart from the first common electrode by a predetermined distance and connected to a pixel area adjacent to the horizontal area in the center of the pixel area; A third common electrode spaced apart from each other in a direction parallel to the data line and formed to connect the first and second common electrodes to each other; A first pixel electrode formed between the first and second common electrodes in a direction parallel to the gate line; Second pixel electrodes formed to connect the first pixel electrodes to both ends of the first pixel electrode; A color filter layer formed on the upper substrate; A black matrix formed on the upper substrate to correspond to an intersection of the gate line and the thin film transistor and the data line and the second common electrode; And a liquid crystal layer formed between the upper and lower substrates, and an alignment layer. The method of claim 1, An orientation direction of the liquid crystal layer is formed in a horizontal direction, and the electric field direction between the data line and the third common electrodes has a direction parallel to the rubbing direction of the alignment layer. LCD display device. delete delete delete delete The method of claim 1, And the first to third common electrodes are formed on the same layer as the gate line. The method of claim 1, And the first and second pixel electrodes are formed on the same layer as the data line. The method of claim 1, And wherein the black matrix is formed of a resin or a metal. delete delete delete delete The method of claim 1, The thin film transistor may include a gate electrode defined in one region of the gate line; A gate insulating film formed on the entire lower substrate; An active layer formed on the gate insulating film above the gate electrode; A source electrode protruding from the data line and overlapping the active layer; And a drain electrode connected to the second pixel electrode at a predetermined distance from the source electrode to extend the drain electrode. delete The method of claim 1, An insulating film made of any one of acrylic, polyimide, BCB, oxide film, and nitride film is further interposed between the first to third common electrodes and the first and second pixel electrodes. IPS) liquid crystal display device.

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