KR100566811B1 - In Plane Switching mode Liquid crystal display device - Google Patents

Abstract

end. Fields to which the invention described in the claims belong:

In-plane switching mode liquid crystal display with improved image quality deterioration due to wide viewing angle and viewing angle.

I. The technical problem the invention is trying to solve:

To improve the color shift and gray level inversion in the middle gray scale, which are fatal problems of the liquid crystal display.

All. The gist of the solution of the invention:

In a liquid crystal display device operating in an in-plane switching (IPS) mode, a pixel electrode and a common electrode are arranged to form a fringe field, thereby forming domains having at least two different directions in one pixel to form a domain of the liquid crystal display device. Improves the image quality reduction characteristic according to the viewing angle.

Description

In-Plane Switching mode Liquid crystal display device             

1 is a cross-sectional view showing a cross section corresponding to one pixel portion of a general liquid crystal display device.

2A and 2B illustrate the operation of the TN mode liquid crystal display device.

3 is a cross-sectional view showing a cross section corresponding to one pixel portion of a liquid crystal display device in a general IPS mode.

4A and 4B are perspective views illustrating the operation of a general IPS mode LCD.

5A and 5B are plan views showing the operation of a liquid crystal display device in a general IPS mode.

6 is a view illustrating color coordinates according to a viewing angle of a general IPS mode liquid crystal display.

7 is a diagram illustrating transmittance according to a viewing angle according to each gray level of a general liquid crystal display.

8A shows the path of light for a single domain of liquid crystal molecules.

8B shows the path of light for multi-domain liquid crystal molecules.

9 illustrates a liquid crystal display device in an IPS mode according to a first embodiment of the present invention.

FIG. 10 is an enlarged view of a portion Z of FIG. 9; FIG.

11 illustrates rotation of liquid crystal molecules along an alignment direction.

12 illustrates a liquid crystal display device in IPS mode according to a second embodiment of the present invention.

FIG. 13 illustrates a liquid crystal display device in an IPS mode according to a third embodiment of the present invention. FIG.

FIG. 14 is an enlarged view of a portion X in FIG. 13; FIG.

FIG. 15 illustrates a liquid crystal display device in an IPS mode according to a fourth embodiment of the present invention. FIG.

FIG. 16 illustrates a liquid crystal display device in IPS mode according to a fifth embodiment of the present invention. FIG.

17 is a diagram showing another example of the fifth embodiment of the present invention;

FIG. 18 illustrates a liquid crystal display device in an IPS mode according to a sixth embodiment of the present invention. FIG.

Fig. 19 shows another example of the sixth embodiment of the present invention.

20 is a view showing a liquid crystal display device in IPS mode according to a seventh embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

50: gate wiring 52: gate electrode

60: common wiring 62: common electrode

63, 73: projection electrode

The present invention relates to an image display device, and more particularly, to a liquid crystal display (LCD) including a thin film transistor (TFT).

In particular, the present invention relates to a liquid crystal display of an in-plane switching (hereinafter referred to as IPS mode) in which first and second electrodes for driving a liquid crystal of a liquid crystal display are formed on the same substrate.

In general, the driving principle of the liquid crystal display device uses the optical anisotropy and polarization of the liquid crystal. Since the liquid crystal is thin and long in structure, the liquid crystal has directivity in the arrangement of molecules, and the direction of the molecular arrangement can be controlled by artificially applying an electric field to the liquid crystal.

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 display image information.

Such liquid crystals may be classified into positive liquid crystals having positive dielectric anisotropy and negative liquid crystals having negative dielectric anisotropy according to electrical characteristics. The liquid crystal molecules having positive dielectric anisotropy have 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 long axis of the liquid crystal molecules.

Currently, active matrix LCDs (AM-LCDs) in which thin film transistors and pixel electrodes connected to the thin film transistors are arranged in a matrix manner have attracted the most attention due to their excellent resolution and video performance.

In general, the structure of a liquid crystal panel, which is a basic component of a liquid crystal display, will be described.

1 is a cross-sectional view showing a cross section of a general TN liquid crystal panel.

In the liquid crystal panel 20, two upper and lower panels 4 and 2 having various kinds of elements formed on the substrate 1 are attached to each other, and a liquid crystal layer between the two panels 2 and 4 is formed. 10) is fitted.

A first electrode connected to a thin film transistor corresponding to each pixel is generally referred to as a pixel electrode, and a second electrode corresponding to the pixel is commonly formed across a plurality of pixels.

The upper panel 4 includes a color filter layer 8 for implementing color and a common electrode 12 covering the color filter layer 8, and the common electrode 12 applies a voltage to the liquid crystal 10. Acts as one electrode. The lower panel 2 is a thin film transistor S serving as a switching role and a pixel electrode 14 serving as an electrode that receives a signal from the thin film transistor S and applies a voltage to the liquid crystal 10. It is composed of

The portion where the pixel electrode 14 is formed is called the pixel portion P. FIG.

In addition, in order to prevent leakage of the liquid crystal 10 injected between the upper panel 4 and the lower panel 2, sealants may be formed at edges of the upper panel 4 and the lower panel 2. It is sealed with).

The liquid crystal display described above has a structure in which a common electrode is formed on a color filter panel which is an upper panel. That is, the liquid crystal display device having a structure in which the common electrode is perpendicular to the pixel electrode drives liquid crystal by an electric field applied up and down, and has excellent characteristics such as transmittance and aperture ratio, and the common electrode of the upper panel is grounded. It serves to prevent the destruction of the liquid crystal cell due to static electricity.

2A and 2B illustrate an operation of the liquid crystal 10 when voltage is applied to the twisted nematic liquid crystal panel, and FIG. 2A is a view showing an arrangement of liquid crystals of the TN liquid crystal panel when no voltage is applied. At this time, the liquid crystal 10 has a positive dielectric anisotropy (+), and has a horizontal arrangement state in which the upper and lower liquid crystals are twisted at 90 ^° in plan view from the alignment direction.

FIG. 2B illustrates an arrangement of liquid crystal molecules when voltage is applied to upper and lower substrates. When voltage is applied to the upper and lower substrates, the liquid crystal molecules 10 twisted to 90 ^o are in the direction of an electric field. As a result, the extreme value of the liquid crystal molecules becomes approximately 90 °.

Therefore, there is a problem in that the change in C / R (contrast ratio) and luminance according to the viewing angle becomes severe, and thus the wide viewing angle cannot be realized.

FIG. 3 is a diagram illustrating a configuration of a liquid crystal display device in the IPS mode proposed to solve the problem of the viewing angle caused by the vertical electric field. The pixel electrode 34 and the common electrode 36 are the same on the substrate 30. It is formed on a plane. That is, the liquid crystal 10 is operated by the horizontal electric field 35 of the pixel electrode 34 and the common electrode 36 on the same substrate 1. The color filter panel 32 is formed on the liquid crystal layer 10.

4A and 4B illustrate a change in arrangement of liquid crystal molecules during voltage on / off in IPS mode. As shown in FIG. 4A, an electric field 35 is not applied to the pixel electrode 34 or the common electrode 36. It is shown that the change of the arrangement of the liquid crystal molecules does not occur in the state.

4B is a diagram illustrating a change in liquid crystal molecular array when a voltage is applied to the pixel electrode 34 and the common electrode 36, and it can be seen that a transverse electric field 35 is formed.

5A and 5B are plan views showing molecular arrangements of liquid crystals according to whether an electric field is applied to the common electrode and the pixel electrode, and FIG. 5A shows a voltage difference between the common electrode 34 and the pixel electrode 35. When not applied, the alignment direction 41 of the liquid crystal molecules is arranged in the same direction as the alignment direction of the initial alignment layer (not shown).

FIG. 5B illustrates an arrangement direction 41a of liquid crystal molecules when a voltage is applied to the pixel electrode 35 and the common electrode 34. It is understood that the liquid crystal molecules are arranged in a direction 42 in which an electric field is applied. Can be.

The advantage of the IPS mode is that the wide field of view is possible because the change of the extreme value of each liquid crystal is small when the electric field is applied. That is, when the liquid crystal display device is viewed from the front, the liquid crystal display device may be visible at about 70 ° in the up / down / left / right directions.

FIG. 6 is a diagram illustrating characteristics of color coordinates according to viewing angles of the liquid crystal display of the IPS mode according to angles of 45 ^° and 135 ^° .

The IPS mode has the advantage of a wide viewing angle, but it can be seen that color shift occurs depending on the viewing angle in standard white light (0.329, 0.333). This is due to the birefringence characteristics of the liquid crystal, and published by S. Endow et al., "18.1-inch Diagonal Super-TFT-LCDs with wide viewing angle and fast response time of 20 ms" (Advanced 18.1-inch Diagonal Super-TFT-LCDs with Mega Wide Viewing Angle and Fast Response Speed of 20ms: IDW 99 ', p. 187) also point to this problem.

FIG. 7 is a diagram illustrating transmittance according to a viewing angle in each gray scale by dividing the gray scales of a general liquid crystal display into eight levels. When the gray scale of 0% transmittance is represented at the front, the viewing angles of the left and right sides are 60 ^o. In the region where the transmittance is about 25%, the transmittance is larger than when the fourth level of gray is expressed.

In other words, one level of gray indicating the dark state indicates the dark state in front, but the left / right viewing angle is about 60 ^o. In this case, gray level inversion occurs, and gray level inversion corresponding to about four levels is generated and becomes a white state instead of a dark state.

Such a phenomenon is referred to as gray scale inversion, and this phenomenon is caused by the birefringence characteristic of the liquid crystal, and thus there is a problem in implementing a high-quality liquid crystal display device due to the inversion of transmittance between gray level.

In order to solve the problems of the conventional liquid crystal display of the TN mode and the liquid crystal display of the IPS mode as described above, an object of the present invention is to provide an excellent liquid crystal display with less color dependence and gray level inversion according to the viewing angle. .

In order to achieve the above object, the present invention includes a gate wiring line and a data wiring line defining a pixel to cross each other on the substrate and extending in a first direction and a second direction, respectively; A thin film transistor formed at a portion where the gate line and the data line cross each other and receiving a signal from the gate and data line; A common wiring extending in the same direction as the gate wiring and receiving a first voltage; a plurality of common electrodes extending into the plurality of electrodes in the common wiring and discontinuously extending in the second direction in a unit pixel; There is provided an array panel for a liquid crystal display device including a plurality of pixel electrodes which are alternately formed in the second direction between the common electrodes and receive a second voltage signal corresponding to the first voltage from the thin film transistor. do.
The common electrode includes a plurality of first electrodes branched from the common wiring in the second direction, and a second electrode extending discontinuously with the first electrode, wherein the second electrode is continuous in the first direction. The pixel electrode may include a first electrode extending in the first direction and a plurality of second electrodes branched from the first electrode in the second direction.
In addition, at least one of the plurality of second electrodes may be configured to be discontinuous, and the second electrode which is not configured to be discontinuous may connect discontinuously extending pixel electrodes to each other. The pixel electrode corresponding to the discontinuity point may further include a protrusion electrode protruding in the direction in which the discontinuity point of the common electrode is formed.
The common electrode corresponding to the discontinuous point of the discontinuously formed pixel electrode may further include a protrusion electrode protruding in the direction in which the discontinuous point of the pixel electrode is formed, and the discontinuous point of the common electrode and the pixel electrode. Is equally dividing the distance between the gate wiring and the common wiring.

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Hereinafter, a liquid crystal display according to the present invention will be described in detail with reference to the accompanying drawings.

In general, the cause of the unevenness of brightness in the halftone in the liquid crystal display is due to the birefringence characteristic of the liquid crystal itself.

That is, the birefringence should be zero between the two polarizers in order to display the complete dark state in the liquid crystal display. However, since the liquid crystal itself is an optical system operating by birefringence, the value is opposite and the magnitude is corrected. Is to create a new system with the same birefringence.

To this end, the present invention uses a method of compensating birefringence of the liquid crystal by forming at least two domains having the same size and opposite directions in the same pixel area.

8A and 8B illustrate differences in birefringence according to viewing angles of a general liquid crystal display and a liquid crystal display having two domains. In the case of a two domain liquid crystal display arranged in different directions, the birefringence value of one direction is shown. Since other domains compensate, the phenomenon of gray level inversion with the viewing angle is reduced.

That is, FIG. 8A is a diagram showing a cross section of a liquid crystal display having one domain, wherein the birefringence values at positions a, b, and c are different. Therefore, in a liquid crystal display having one domain shown in FIG. 8A, a deterioration in image quality characteristics inevitably occurs due to a viewing angle.

Figure 8b is a diagram showing the cross section of a liquid crystal display device forming the two domains in the pixel region, the second liquid-crystal birefringence value of a _first of the liquid crystal molecules will take a molecular arrangement in a direction opposite to the first liquid crystal molecules The birefringence value of a ₂ of the molecule is compensated (as a result, the birefringence value is about 0), so that the deterioration of the image quality according to the viewing angle is small.

As described above, the present invention relates to changing the structure of the liquid crystal display to have a multi domain by changing the structure of the electrode in the liquid crystal display of the IPS mode.

First embodiment

In the first embodiment of the present invention, in the IPS mode liquid crystal display, pixel electrodes or common electrodes are alternately arranged to form multi-domains, and discontinuous portions are formed on the staggered pixel electrodes or common electrodes to disperse the arrangement of electric fields. By trimming, it is about forming two domains.

9 is a plan view of a liquid crystal display according to a first exemplary embodiment of the present invention, in which pixel electrodes and a common electrode are alternately formed.

Referring to the configuration of the liquid crystal display according to the first embodiment of the present invention shown in FIG. 9 in more detail, the gate wiring 50 and the common wiring 60 are arranged parallel to each other in the horizontal direction, and in the vertical direction The data line 70 is located.

A gate electrode 52 and a source electrode 72 are formed on the gate line 50 and the data line 70 at the portion where the gate line 50 and the data line 70 cross each other, and the source electrode 72 is formed. ), A drain electrode 74 is formed.

On the other hand, the common wires 60 arranged in the horizontal direction are formed with a plurality of common electrodes 62 branched in the vertical direction. The common electrode 62 is formed in a direction in which the data line 70 extends, and is discontinuously formed at an arbitrary position.

In addition, the pixel electrode 76 is in contact with the drain electrode 74 and alternately with the common electrode 62 in a direction in which the common electrode 62 is branched.

As described above, domain regions (i.e., first and second domain regions in FIG. 9) different from each other are formed on the basis of the discontinuous point C of the common electrode 62 discontinuously formed. This is explained in detail.

FIG. 10 is an enlarged view of a portion Z of FIG. 9, and illustrates an electric field formed between the common electrode 62 and the pixel electrode 76 and a molecular arrangement direction of the liquid crystal 80 according to the electric field in detail.

Here, a fringe field is formed in which electric fields applied to the upper and lower parts of the common electrode 62 discontinuously disperse in opposite directions.

Therefore, the liquid crystal 80 positioned above and below the discontinuity point C is formed with first and second domains arranged in different directions according to application of an electric field.

The reason why the liquid crystals are arranged in opposite directions with respect to the discontinuity point C as described above is that the degree of freedom of the liquid crystal becomes two.

That is, as shown in FIG. 11, when the molecular arrangement direction (that is, the alignment direction) of the initial liquid crystal is the same direction as the extension direction of the pixel electrode 76 and the common electrode 62, the degree of freedom of the liquid crystal is Since it is 2, it is arranged left / right. At this time, the force causing the liquid crystal to be arranged left / right is due to the electric field disturbed at the discontinuous point C, and two different domains are formed by this electric field.

On the other hand, a positive liquid crystal having a dielectric constant anisotropy is used as the electrical property of the liquid crystal used in the first embodiment of the present invention, wherein the alignment direction for determining the molecular alignment direction of the initial liquid crystal is The common electrode and the pixel electrode extend in the same direction (ie, vertical direction).

In addition, if a liquid crystal having a negative dielectric anisotropy is used, the alignment direction of the initial liquid crystal will be a horizontal direction (ie, a direction in which the common wiring and the gate wiring extend).

By forming the liquid crystal display as described above, in the conventional IPS mode liquid crystal display operating in the birefringence mode, the dependence of the wavelength according to the viewing angle is strong, but in the first embodiment of the present invention in two different directions in the plane The two moving domains compensate each other for color characteristics according to the viewing angle, thereby reducing gradation inversion according to the viewing angle.

Second embodiment

Compared to the formation of the common electrode and the pixel electrode in the vertical direction in the first embodiment, the liquid crystal display device of the IPS mode according to the second embodiment of the present invention is to form the positions of the common electrode and the pixel electrode in the horizontal direction. It is about.

FIG. 12 is a plan view of a liquid crystal display device in an IPS mode according to a second embodiment of the present invention. The gate line 50 is formed in the horizontal direction and the data line 70 is formed in the vertical direction.

In addition, a common wiring 60 is formed in parallel with the gate wiring 50, and a first common wiring auxiliary electrode 64a is vertically branched on the common wiring 60, and the first common wiring auxiliary is formed. The second common wiring auxiliary electrode 64b is formed to be spaced apart from the electrode 64a by a predetermined interval and vertically branched from the common wiring 60.

The first and second common wiring auxiliary electrodes 64a and 64b are divided between the first and second common wiring auxiliary electrodes 64a and 64b in the direction in which the auxiliary electrodes 64a and 64b face each other. A plurality of common electrodes 62 are formed, that is, the common electrodes 62 substantially affecting the molecular arrangement by applying an electric field to the liquid crystal in a direction in which the gate wiring 50 extends (ie, in a horizontal direction). The intermediate regions of the first and second common wiring auxiliary electrodes 64a and 64b are discontinuously formed with respect to the reference C.

A thin film transistor S is formed as a switching element at a portion where the data line 70 and the gate line 50 cross each other, and the pixel electrode 76 contacting the thin film transistor S is the common electrode 62. ) Are staggered from each other in the direction in which they are formed.

As described above, the liquid crystal display according to the second exemplary embodiment of the present invention has a pixel electrode 76 and a common electrode which substantially affect the molecular arrangement of the liquid crystal as compared to the liquid crystal display described in the first exemplary embodiment. The arrangement position of 62) is different.

That is, in the first embodiment of the present invention, the pixel electrode 76 and the common electrode 62 are formed in the direction in which the data line 70 extends. In the second embodiment of the present invention, the pixel electrode 76 is formed. ) And the common electrode 62 are formed in a direction in which the gate wiring 50 extends.

On the other hand, in the liquid crystal display according to the second embodiment of the present invention, if the alignment direction for determining the initial arrangement direction of the liquid crystal molecules is a direction in which the pixel electrode 76 and the common electrode 62 are formed, the dielectric anisotropy is positive (+). When the positive liquid crystal is used, and the alignment direction is perpendicular to the direction in which the pixel electrode 76 and the common electrode 62 are formed, a negative liquid crystal having a negative dielectric anisotropy is used.

In addition, in the operation of the liquid crystal display according to the second exemplary embodiment of the present invention, first and second domain regions are formed on the left and right sides based on the discontinuous point C of the common electrode 62 formed vertically. Since the function is the same as in the first embodiment, detailed description thereof will be omitted.

Third embodiment

In the above-described first and second embodiments, a common electrode is formed discontinuously, and thus, a method of forming a molecular alignment direction of liquid crystals differently by using disturbance of an electric field at the discontinuous point is provided.

The third embodiment of the present invention relates to a structure of a liquid crystal display device in which both the pixel electrode and the common electrode are discontinuously formed.

In this case, the position of each discontinuity point of the pixel electrode and the common electrode is such that the discontinuity point of the pixel electrode is positioned at 1/3 of the length of all the pixel electrodes or the common electrode, and the discontinuity point of the common electrode is located at 2/3 of the common electrode. The position of each discontinuity point may be changed.

Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

FIG. 13 is a plan view of a liquid crystal display device according to a third embodiment of the present invention. The basic configuration is similar to that of FIG. 9 showing the liquid crystal display device according to the first embodiment. ) And the part of the common electrode 62 are different.

As mentioned above, as shown in FIG. 13, the pixel electrodes 76 and the common electrode 62 have discontinuous points on the electrodes 76 and 62, respectively.

Here, the position of the first discontinuity point C ₁ , which is the discontinuity point of the common electrode 62, is formed at a third point of the length of the common electrode 62 and the second discontinuity point of the pixel electrode 76. (C ₂ ) are each formed at 2/3 points.

In other words, the adjacent common electrode 62 corresponding to the portion where the discontinuous point C ₂ of the pixel electrode 76 is formed extends linearly, and conversely, the discontinuous point C ₁ of the common electrode 62. Adjacent pixel electrode 76 corresponding to the portion where? Is formed extends linearly.

When the pixel electrode 76 and the common electrode 62 are configured as described above, the first, second, and third domains are respectively formed on the upper, middle, and lower portions based on the first and second discontinuities C ₁ and C ₂ . An area is formed.

FIG. 14 is an enlarged view of a portion X of FIG. 13 and illustrates an arrangement of an electric field E and an alignment direction of liquid crystal molecules 80 formed between the pixel electrode 76 and the common electrode 76.

As shown in FIG. 14, when the pixel electrode 76 and the common electrode 62 of the liquid crystal display according to the third exemplary embodiment of the present invention are configured, 3 is determined based on the discontinuities formed on the electrodes 62 and 76. Two different first, second, and three domain regions are formed.

On the other hand, since there are discontinuities C ₁ and C _{2 in} each of the electrodes 62 and 76, the external shock (electric field) is stronger than in the first embodiment in which only one discontinuity is in the common electrode. The resiliency of the liquid crystal is increased, so that the response characteristic of the liquid crystal is increased, and the resilience to the initial luminance is achieved within a shorter time.

Here, in the liquid crystal display, when the initial alignment direction of the liquid crystal is parallel to the direction of each electrode (pixel and common electrode), a liquid crystal having a positive dielectric anisotropy is used, and the alignment direction is each electrode (pixel and common electrode). When perpendicular to, the liquid crystal has a negative dielectric anisotropy.

Fourth embodiment

The fourth embodiment according to the present invention relates to the arrangement of each electrode (pixel electrode and common electrode) of the liquid crystal display according to the third embodiment in the horizontal direction instead of the vertical direction as in the second embodiment.

In other words, in the second embodiment, the discontinuous points C ₁ and C ₂ may be formed on the pixel electrode in the same manner as in the third embodiment to manufacture the liquid crystal display as shown in FIG. 15. .

That is, as shown in FIG. 15, first and second common wiring auxiliary electrodes 64a and 64b branched from the common wiring 60 in the vertical direction are formed in the common wiring 60 arranged in the horizontal direction. Each of the common wiring auxiliary electrodes 64a and 64b includes a plurality of common electrodes 76 which are branched in the horizontal direction with discontinuities C ₁ .

On the other hand, the pixel electrode 76 is formed with a discontinuous point (C ₂ ) between each of the common electrode 62 and the common electrode 62 alternately.

In addition, the alignment direction for determining the initial arrangement of the liquid crystal uses a positive liquid crystal when the liquid crystal is aligned in parallel with the electrodes (pixel electrode and common electrode), and a negative liquid crystal when the liquid crystal is vertically aligned. Will be used.

Here, the liquid crystal display according to the fourth embodiment of the present invention performs the same operation as the liquid crystal display of the third embodiment, and a detailed description thereof will be omitted.

Fifth Embodiment

In the fifth embodiment according to the present invention, in the structure of the liquid crystal display device according to the first and second embodiments described above, protrusions are formed on the pixel electrodes corresponding to the discontinuously formed common electrodes to further increase the electric field applied to the positive electrodes. The present invention relates to a structure of a liquid crystal display device that further deepens distortion.

Hereinafter, a structure of a liquid crystal display according to a fifth exemplary embodiment of the present invention will be described with reference to FIG. 16.

FIG. 16 illustrates the discontinuously formed common electrode on the pixel electrode 76 corresponding to the discontinuous point C portion of the common electrode 62 discontinuously formed in the structure of the liquid crystal display according to the first exemplary embodiment of the present invention. The plane of the liquid crystal display in which the protruding electrode 77 is formed in the direction of 62 is shown.

That is, when the projection electrode 77 is formed on the pixel electrode 76 of the liquid crystal display according to the fifth embodiment of the present invention, when an electric field is formed between the common electrode 62 and the pixel electrode 76, It is possible to manufacture a liquid crystal display device capable of more effectively distorting an electric field.

According to the spirit of the fifth embodiment of the present invention as described above, the structure of the liquid crystal display device according to the second embodiment of the present invention may also be changed, and as shown in FIG.

Here, the detailed description and structure of the drawings with respect to FIG. 17 are omitted.

Sixth embodiment

In the sixth embodiment according to the present invention, the pixel electrode 76 corresponding to the common electrode 62 and the pixel electrode 76 formed discontinuously in the structure of the liquid crystal display device according to the third and fourth embodiments described above, and The present invention relates to a structure of a liquid crystal display device in which protrusions are formed on the common electrode 62 to make the electric field applied to the positive electrodes (pixel electrode and common electrode) stronger and further increase distortion.

FIG. 18 corresponds to portions of the first and second discontinuities C ₁ and C ₂ of the common electrode 62 and the pixel electrode 76 discontinuously formed in the structure of the liquid crystal display according to the third exemplary embodiment of the present invention. The plane of the liquid crystal display in which the projection electrodes 77 and 63 are formed in the direction of the pixel electrode 76 and the common electrode 62 and the discontinuously formed common electrode 62 and the pixel electrode 76 is shown. Drawing.

As described above, when the pixel electrode 76 and the common electrode 62 are formed, multiple domains are formed by an electric field in which the molecular structure of the liquid crystal is irregularly distorted to each of the electrodes although the above-mentioned fifth embodiment is mentioned. It is possible to improve the characteristics of image quality deterioration according to the viewing angle.

19 is a view showing a modified view of the structure of a liquid crystal display according to a fourth embodiment of the present invention according to the spirit of the sixth embodiment of the present invention as described above. The description thereof is omitted.

Seventh embodiment

In the seventh exemplary embodiment of the present invention, in the structure of the liquid crystal display according to the sixth exemplary embodiment, the protrusion electrodes 77 and 63 formed on the respective electrodes are formed to be in contact with the adjacent protrusion electrodes, and the discontinuous points C ₁ and C _{2 are formed.} ) And linearly connect the pixel electrode and the common electrode in a checkerboard shape.

FIG. 20 is a plan view of a liquid crystal display according to a seventh embodiment of the present invention. In FIG. 18 showing a sixth embodiment, the projection electrodes 77 and 63 are adjacent to the projection electrodes. The auxiliary common electrode 65 is formed in a direction perpendicular to the direction in which the common electrode 62 is formed, and the auxiliary pixel electrode is in a direction perpendicular to the direction in which the pixel electrode 76 is formed. 79 is formed.

In other words, the pixel electrode and the common electrode 76 and 62 are formed in the direction in which the data line 70 extends, and the auxiliary pixel electrode and the auxiliary common electrode 79 and 65 are formed in the gate line 50. It is formed in the extending direction.

By forming the pixel electrode and the auxiliary pixel electrodes 76 and 79 and the common and auxiliary common electrodes 62 and 65 in the shape of a checkerboard as described above, the distortion degree of the electric field applied to each electrode and the intensity of the electric field are increased. As a result, the response speed of the liquid crystal is increased.

In addition, as shown in FIG. 20, the liquid crystals positioned in the divided spaces formed by the respective electrodes may have multiple domains arranged in different directions, thereby improving color shift characteristics according to viewing angles.

Although not shown in the drawings, as in the liquid crystal display described in the fourth embodiment, the pixel electrode and the common electrode 76 and 62 are formed in the direction in which the gate wiring 50 extends and the auxiliary pixel electrode and the auxiliary common electrode. The 79 and 65 may be formed in the direction in which the data line 70 extends.

As described above, the present invention, as described in detail in each embodiment, the basic concept is that the conventional IPS mode of the liquid crystal display device in order to improve the poor quality of the image according to the viewing angle, such as color shift and gradation inversion depending on the viewing angle, So that each domain can compensate for each other.

To this end, each embodiment of the present invention uses a method of changing the structure of the pixel electrode or the common electrode to disturb the arrangement of the electric field applied to each electrode (pixel electrode, common electrode).

As described above, when the direction of the electric field is distorted by changing the pixel electrode and the common electrode, a plurality of domains are formed which are arranged in different directions according to the application of the electric field, and these domains compensate for the birefringence of light according to the viewing angle. There is an advantage of improving the deterioration of the image quality according to the viewing angle.

In addition, by forming the protruding electrode or the auxiliary electrode in the vertical direction of the pixel electrode and the common electrode, the electric field applied to each electrode (pixel electrode, common electrode) is distorted, and the intensity of the electric field applied to each electrode becomes stronger, thereby responding to the liquid crystal. The speed is improved.

As described above, the liquid crystal display according to the exemplary embodiments of the present invention has the following characteristics.

First, in the liquid crystal display of the conventional IPS mode, the liquid crystal molecules are rotated in one direction in a plane, so that the color inversion according to the viewing angle exists, but the liquid crystal display according to the present invention rotates in at least two different opposite directions. As the domain is formed, there is an advantage of improving the characteristics of color inversion according to the viewing angle.

Second, there is an advantage that can improve the characteristics of grayscale inversion according to the viewing angle by the two domains that rotate in different directions.

Third, by forming the protruding electrode or the auxiliary electrode on the pixel electrode and the common electrode, the intensity of the electric field applied to each electrode is increased, thereby improving the response speed of the liquid crystal.

Claims (17)

A gate line and a data line intersecting each other on the substrate to define pixels, and extending in first and second directions, respectively; A thin film transistor formed at a portion where the gate line and the data line cross each other and receiving a signal from the gate and data line; A common wiring extending in the same direction as the gate wiring and receiving a first voltage; A plurality of common electrodes extending into the plurality of electrodes on the common wiring and discontinuously extending in the second direction in a unit pixel; A plurality of pixel electrodes interposed between the common electrodes in the second direction and receiving a second voltage signal corresponding to the first voltage from the thin film transistor; Array panel for a liquid crystal display device comprising a. The method according to claim 1, The common electrode includes a plurality of first electrodes branched from the common wiring in the second direction, and a second electrode extending discontinuously with the first electrode, wherein the second electrode is continuous in the first direction. An array panel for a liquid crystal display device, characterized in that extending. The method according to claim 1, And the pixel electrode includes a first electrode extending in the first direction and a plurality of second electrodes branched from the first electrode in the second direction. The method according to claim 3, At least one of the plurality of second electrodes is configured to be discontinuous, and the second electrode which is not configured as the discontinuous connects the discontinuously extended pixel electrodes to each other. The method according to claim 1, The pixel electrode corresponding to the discontinuous point of the discontinuously formed common electrode further includes a projection electrode protruding in a direction in which the discontinuous point of the common electrode is formed. The method according to claim 1, And the common electrode corresponding to the discontinuous point of the discontinuously formed pixel electrode further includes a protruding electrode protruding in a direction in which the discontinuous point of the pixel electrode is formed. The method according to claim 2 or 4, The discontinuity point of the common electrode and the pixel electrode divides the distance between the gate wiring and the common wiring evenly. A gate line and a data line intersecting each other on the substrate to define pixels, and extending in first and second directions, respectively; A thin film transistor formed at a portion where the gate line and the data line cross each other and receiving a signal from the gate and data line; A common wiring extending in the same direction as the gate wiring and having a first auxiliary wiring branched in the second direction in the unit pixel and a second auxiliary wiring spaced apart from the first auxiliary wiring by a predetermined distance; A plurality of common electrodes extending vertically discontinuously from the first and second auxiliary wires in a direction in which the first and second auxiliary wires face each other; A plurality of pixel electrodes alternately interposed between the common electrodes after receiving a signal from the thin film transistor Array panel for a liquid crystal display device comprising a. The method according to claim 8, And each pixel electrode further includes a discontinuity point in an extended direction thereof. The method according to claim 8, And a plurality of discontinuous common electrodes, wherein each discontinuous point of the common electrode extends along the second direction. The method according to claim 8, And a plurality of discontinuous pixel electrodes, each discontinuous point of the pixel electrode extending in the second direction. The method according to claim 8, The pixel electrode corresponding to the discontinuous point of the discontinuously formed common electrode further includes a projection electrode protruding in a direction in which the discontinuous point of the common electrode is formed. The method according to claim 8, And the common electrode corresponding to the discontinuous point of the discontinuously formed pixel electrode further includes a protruding electrode protruding in a direction in which the discontinuous point of the pixel electrode is formed. The method according to claim 10 or 11, And a discontinuous point of the common electrode and the pixel electrode divides the distance between the data line and the adjacent data line evenly. A gate line and a data line intersecting each other on the substrate to define pixels, and extending in first and second directions, respectively; A thin film transistor formed at a portion where the gate line and the data line cross each other and receiving a signal from the gate and data line; A common wiring extending in the same direction as the gate wiring; A common electrode which is vertically branched from the common wiring and constituted in plurality in the unit pixel; A plurality of pixel electrodes that receive signals from the thin film transistors and are alternately formed between the common electrodes; An auxiliary common electrode formed in a first direction in contact with each of the common electrodes; An auxiliary pixel electrode in contact with each of the pixel electrodes and formed in a first direction without overlapping the auxiliary common electrode; Array panel for a liquid crystal display device comprising a. A gate line and a data line intersecting each other on the substrate to define pixels, and extending in first and second directions, respectively; A thin film transistor formed at a portion where the gate line and the data line cross each other and receiving a signal from the gate and data line; A common wiring extending in the same direction as the gate wiring and vertically branching and having a first auxiliary wiring and a second auxiliary wiring spaced apart from the first auxiliary wiring by a predetermined distance in the unit pixel; A plurality of common electrodes vertically branched from the first and second auxiliary wires in a direction in which the first and second auxiliary wires face each other; A pixel electrode receiving a signal from the thin film transistor and staggered between the common electrodes; A plurality of auxiliary common electrodes in contact with the common electrodes and formed in a second direction; An auxiliary pixel electrode in contact with each of the pixel electrodes and formed in a second direction without overlapping the auxiliary common electrode; Array panel for a liquid crystal display device comprising a. A gate line and a data line intersecting each other on the substrate to define pixels, and extending in first and second directions, respectively; A thin film transistor formed at a portion where the gate line and the data line cross each other and receiving a signal from the gate and data line; A common wiring applied with a first voltage and having a plurality of common electrodes in the unit pixels; A plurality of pixel electrodes receiving a second voltage corresponding to the first voltage from the thin film transistor and staggered in the same extension direction as the plurality of common electrodes; A plurality of auxiliary electrodes connecting the plurality of common electrodes and the plurality of pixel electrodes in a checkered pattern, respectively Array panel for a liquid crystal display device comprising a.

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