KR20120047171A - Liquid crystal display device and method of driving the same - Google Patents

Abstract

The present invention provides a display device comprising: a first substrate having a plurality of pixel regions defined therein; A first electrode positioned inside each of the plurality of pixel regions and having a plate shape inside the first substrate; A protective layer covering the first electrode; A second electrode on each of the plurality of pixel regions on the passivation layer, the second electrode having at least one opening with respect to the first electrode; A second substrate facing the first substrate; A third electrode disposed inside the second substrate and covering the entire pixel area; The present invention provides a liquid crystal display including a liquid crystal layer positioned between the second electrode and the third electrode.

Description

Liquid crystal display device and method of driving the same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device having a wide viewing angle and having a high brightness and a high contrast ratio by using a transverse electric field and a driving method thereof.

Generally, the driving principle of a liquid crystal display device utilizes the optical anisotropy and polarization properties of a liquid crystal. Since the liquid crystal has a long structure, it has a directionality 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.

Therefore, when the molecular alignment direction of the liquid crystal is arbitrarily adjusted, the molecular arrangement of the liquid crystal is changed, and light is refracted in the molecular alignment direction of the liquid crystal by optical anisotropy, so that image information can be expressed.

Currently, an active matrix liquid crystal display device (AM-LCD: abbreviated as an active matrix LCD, abbreviated as a liquid crystal display device) in which a thin film transistor and pixel electrodes connected to the thin film transistor are arranged in a matrix manner has the best resolution and video performance. It is attracting attention.

The liquid crystal display includes a color filter substrate on which a common electrode is formed, an array substrate on which pixel electrodes are formed, and a liquid crystal interposed between the two substrates. In such a liquid crystal display, the common electrode and the pixel electrode are caused by an electric field applied up and down. It is excellent in the characteristics, such as transmittance | permeability and aperture ratio, by the method of driving a liquid crystal.

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

Accordingly, a transverse field type liquid crystal display device having excellent viewing angle characteristics has been proposed to overcome the above disadvantages.

Hereinafter, a general transverse electric field type liquid crystal display device will be described in detail with reference to FIG. 1.

1 is a cross-sectional view of a general transverse electric field type liquid crystal display device.

As shown, the upper substrate 9, which is a color filter substrate, and the lower substrate 10, which is an array substrate, are spaced apart from each other, and the liquid crystal layer 11 is interposed between the upper and lower substrates 9, 10. It is.

The common electrode 17 and the pixel electrode 30 are formed on the lower substrate 10 on the same plane. In this case, the liquid crystal layer 11 is formed by the common electrode 17 and the pixel electrode 30. It is operated by the horizontal electric field (L).

2A and 2B are cross-sectional views illustrating operations of ON and OFF states of a general transverse electric field type liquid crystal display device, respectively.

First, referring to FIG. 2A, which illustrates an arrangement of liquid crystals in an on state where a voltage is applied, a phase change of a liquid crystal 11a at a position corresponding to the common electrode 17 and the pixel electrode 30 is performed. Although the liquid crystal 11b positioned in the section between the common electrode 17 and the pixel electrode 30 is formed by the horizontal electric field L formed by applying a voltage between the common electrode 17 and the pixel electrode 30, It is arranged in the same direction as the horizontal electric field (L). That is, in the transverse electric field type liquid crystal display device, since the liquid crystal moves by the horizontal electric field, the viewing angle is widened.

Next, referring to FIG. 2B, since no voltage is applied to the liquid crystal display, a horizontal electric field is not formed between the common electrode and the pixel electrode, so that the arrangement state of the liquid crystal layer 11 does not change.

Such a transverse electric field type liquid crystal display device arranges the directors of the liquid crystals of the upper and lower plates so as to coincide with the transmission axis of one polarizing plate in a state where no voltage is applied, and in this case, arranges the polarizing plates of the upper and lower plates in an orthogonal arrangement. It is driven in a normally black mode that obtains black characteristics.

On the other hand, when a voltage is applied to the electric field is formed, the liquid crystal is rotated so that the long axis direction of the liquid crystal in parallel in the horizontal electric field (in plane field) direction. In this case, the transmittance depends on the transmission axis of the polarizing plate, the rotation angle of the long axis director of the liquid crystal, the birefringence of the liquid crystal layer, and the thickness of the liquid crystal layer, and are expressed by the following equation.

Is the rotation angle of the transmission axis of the polarizing plate and the long axis director of the liquid crystal, Δn is the birefringence of the liquid crystal layer, and d is the thickness of the liquid crystal layer. The transmittance expressed by the above equation is increased by voltage application.

However, the conventional transverse electric field type liquid crystal display device having the above-described configuration has some problems. That is, referring to FIG. 3, which illustrates a driving state of a conventional transverse electric field type liquid crystal display device, the liquid crystal molecules 72 of the liquid crystal layer 70 interposed between the first substrate 50 and the second substrate 60 facing each other. Is driven by the pixel electrode 52 and the common electrode 54 positioned on the first substrate 50, and is effective on the pixel electrode 52 and the common electrode 54 in a voltage-on state. Since no effective electric field is formed, the liquid crystal molecules 72 do not rotate. Therefore, the more the pixel electrode 52 and the common electrode 54 are formed, the lower the transmission efficiency and the substantial aperture ratio of light passing through the liquid crystal layer. In other words, there is a problem that the brightness is lowered.

In addition, although the pixel electrode 52 and the common electrode 54 have a strong electric field on the first substrate 50 side, the electric field is weakened and distorted toward the second substrate 60. In particular, a substantially vertical electric field is formed in the vicinity of the pixel electrode 52 and the common electrode 54 so that the director of the liquid crystal molecules 72 is arranged perpendicular to the first substrate 50. Therefore, in the equation representing the above transmittance, a value of the second sin square term becomes small, thereby causing a problem that the transmittance is further lowered.

As a result, the conventional transverse electric field type liquid crystal display has limitations in brightness and contrast ratio. There is also a limit on the actual aperture ratio.

The present invention seeks to overcome the disadvantages of aperture ratio, luminance, and contrast ratio which occur in conventional transverse electric field type liquid crystal display devices.

Accordingly, an object of the present invention is to provide a liquid crystal display device having advantages in aperture ratio, brightness, and contrast ratio while obtaining a wide viewing angle.

In order to solve the above problems, the present invention includes a first substrate having a plurality of pixel areas defined; A first electrode positioned inside each of the plurality of pixel regions and having a plate shape inside the first substrate; A protective layer covering the first electrode; A second electrode on each of the plurality of pixel regions on the passivation layer, the second electrode having at least one opening with respect to the first electrode; A second substrate facing the first substrate; A third electrode disposed inside the second substrate and covering the entire pixel area; The present invention provides a liquid crystal display including a liquid crystal layer positioned between the second electrode and the third electrode.

A first polarizing plate positioned outside the first substrate and having a first transmission axis; And a second polarizing plate positioned outside the second substrate and having a second transmission axis perpendicular to the first transmission axis.

A first alignment layer positioned between the second electrode and the liquid crystal layer and parallel to any one of the first transmission axis and the second transmission axis; And a second alignment layer positioned between the third electrode and the liquid crystal layer and parallel to another one of the first transmission axis and the second transmission axis.

First and second gate lines spaced apart from each other in parallel; First and second data lines crossing the first and second gate lines and spaced apart in parallel; A first thin film transistor connected to the first gate line and the first data line; And a second thin film transistor connected to the second gate line and the second data line, wherein the first electrode is connected to the first thin film transistor, and the second electrode is connected to the second thin film transistor. to be.

Each of the first and second thin film transistors includes a gate electrode, a semiconductor layer, a source electrode, and a drain electrode, and gate electrodes of the first and second thin film transistors are respectively connected to the first and second gate lines. Source electrodes of the first and second thin film transistors are connected to the first and second data lines, respectively, and the first electrode is in direct contact with a drain electrode of the first thin film transistor, and the second electrode Is in contact with the drain electrode of the second thin film transistor through a contact hole formed in the protective layer.

Each of the first to third electrodes is made of a transparent conductive material.

In another aspect, the present invention provides a display device comprising: a first substrate having a plurality of pixel regions defined therein; A first electrode positioned inside each of the plurality of pixel regions and having a plate shape inside the first substrate; A second electrode having at least one opening with respect to said first electrode; A second substrate facing the first substrate; A third electrode disposed inside the second substrate and covering the entire pixel area; A liquid crystal display device comprising a liquid crystal layer positioned between the second electrode and the third electrode, comprising: floating the first and second electrodes to display an image having a first brightness; Displaying an image of a second luminance smaller than the first luminance by generating a first voltage difference between the first and second electrodes to drive the liquid crystal layer; Driving the liquid crystal layer by generating a voltage difference greater than the first voltage difference between the first and third electrodes to display an image of a third brightness less than the second brightness. Provide a method.

In the displaying of the image of the second luminance, the average value of the voltages applied to each of the first and second electrodes is the same as the voltage applied to the third electrode.

The displaying of the image having the third luminance may include applying a voltage equal to the voltage applied to the first electrode to the second electrode.

The present invention provides a normally white mode using first and second electrodes formed on a lower substrate to form a fringe field, and a third electrode formed on a front surface of the upper substrate to form a vertical electric field with the first and second electrodes. By providing a liquid crystal display device, a high aperture ratio and a high contrast ratio can be obtained.

In addition, a wide viewing angle can be obtained by driving the fringe field.

1 is a cross-sectional view of a general transverse electric field type liquid crystal display device.
2A and 2B are cross-sectional views illustrating operations of ON and OFF states of a general transverse electric field type liquid crystal display device, respectively.
3 is a cross-sectional view illustrating a driving state in a general transverse electric field type liquid crystal display device.
4 is a schematic cross-sectional view illustrating a part of a liquid crystal display according to an exemplary embodiment of the present invention.
5 is a schematic plan view showing a portion of an array substrate for a liquid crystal display according to an exemplary embodiment of the present invention.
6A through 6C are cross-sectional views illustrating a driving state of a liquid crystal display according to an exemplary embodiment of the present invention.
7A and 7B are graphs showing simulation results of driving voltage and transmittance of a liquid crystal display according to an exemplary embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings.

4 is a schematic cross-sectional view illustrating a part of a liquid crystal display according to an exemplary embodiment of the present invention.

As shown in FIG. 4, the liquid crystal display according to the exemplary embodiment of the present invention includes a first substrate 110, a second substrate 120 facing the first substrate 110, and the first and second electrodes. The liquid crystal layer 170 interposed between the substrates 110 and 120, the first and second polarizing plates 182 and 184 positioned outside the first and second substrates 110 and 120, and the The first electrode 118 and the second electrode 140 are positioned inside the first substrate 110, and the third electrode 160 is positioned inside the second substrate 120.

Although not shown, the liquid crystal molecules of the liquid crystal layer 170 have a 90 ° twisted state. The first polarization axis of the first polarization plate 182 and the second polarization axis of the second polarization plate 184 are perpendicular to each other, and the long axis of the liquid crystal molecules of the liquid crystal layer proximate to the first substrate 110 may be formed in the first polarization axis. The long axis of the liquid crystal molecules of the liquid crystal layer arranged in parallel and adjacent to the second substrate 120 is arranged parallel to the second polarization axis. In contrast, the long axis of the liquid crystal molecules of the liquid crystal layer adjacent to the first substrate 110 is arranged parallel to the second polarization axis, and the long axis of the liquid crystal molecules of the liquid crystal layer adjacent to the second substrate 120 is the first polarization axis. It can be arranged parallel to. That is, the long axis of the liquid crystal molecules of the liquid crystal layer adjacent to the first substrate 110 is arranged in parallel to any one of the first polarization axis and the second polarization axis and the liquid crystal molecules of the liquid crystal layer adjacent to the second substrate 120. The major axis of is arranged parallel to the other of the first polarization axis and the second polarization axis.

A gate insulating layer 116 is disposed below the first electrode 118 inside the first substrate 110. The first electrode 118 is independently positioned in each of the plurality of pixel regions P defined in the first substrate 110 and has a plate shape. That is, the first electrode 118 in one pixel region P is spaced apart from the first electrode 118 in the other pixel region P, and thus has an electrically insulated state. The second electrode 150 is also positioned independently of each of the plurality of pixel regions P and has at least one opening 152. That is, the second electrode 150 is configured to have the opening 152 corresponding to the first electrode 118 while overlapping the first electrode 118 through the protective layer 140.

Meanwhile, the third electrode 160 covers the inner front surface of the second substrate 120. That is, the third electrode 160 is integrally formed in the entire pixel areas P.

Each of the first to third electrodes 118, 150, and 160 may be formed of a transparent conductive material such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO). Is made of.

Although not shown, a first alignment layer is disposed on the first substrate 110 to cover the second electrode 150 and determine an initial arrangement of liquid crystal molecules, and the third substrate 120 is disposed on the third substrate 120. A second alignment layer is disposed to cover the electrode 160 and to determine an initial arrangement of liquid crystal molecules. The first alignment layer is aligned parallel to either one of the first polarization axis and the second polarization axis, and the first alignment layer is aligned parallel to the other of the first polarization axis and the second polarization axis.

5 is a schematic plan view showing a portion of an array substrate for a liquid crystal display according to an exemplary embodiment of the present invention.

As shown in FIG. 5, the array substrate for a liquid crystal display according to the exemplary embodiment of the present invention is positioned on the first substrate 110 and crosses each other to define the gate line 112 and the data defining the pixel region P. FIG. A wire 130, a first electrode 118 and a second electrode 150 positioned in the pixel region P, and a first electrode 118 connected to the first electrode 118 and applied to the first electrode 118. A first thin film transistor Tr1 for controlling a signal and a second thin film transistor Tr2 for controlling a signal applied to the second electrode 150 are included.

The gate line 112 includes first and second gate lines 112a and 112b spaced apart from each other in a first direction in the vertical direction of the pixel area P. The data line 130 includes the pixel. The first and second data lines 130a and 130b are spaced apart from each other along the second direction to the left and right of the area P. Here, the first direction is parallel to the first polarization axis of the first polarizing plate 182 of FIG. 4, and the second direction is parallel to the second polarization axis of the second polarizing plate 184 of FIG. 4.

The first thin film transistor Tr1 is disposed on the first gate electrode 114a connected to the first gate line 112a and overlaps the first gate electrode 114a. A first semiconductor layer (not shown), a first source electrode 132a positioned on the first semiconductor layer and connected to the first data line 130a, and a first semiconductor layer positioned on the first semiconductor layer. The first drain electrode 134a is spaced apart from the first source electrode 132a. That is, the first thin film transistor Tr1 is connected to the first gate line 112a and the first data line 130a.

In addition, the second thin film transistor Tr2 is disposed on the second gate electrode 114b and the second gate electrode 114b connected to the second gate line 112b, and is positioned on the second gate electrode 114b. A second semiconductor layer (not shown) overlapping the second semiconductor layer, a second source electrode 132b disposed on the second semiconductor layer and connected to the second data line 130b, and positioned on the second semiconductor layer. And a second drain electrode 134b spaced apart from the first source electrode 132b. That is, the second thin film transistor Tr2 is connected to the second gate line 112b and the second data line 130b.

The gate insulating layer 116 of FIG. 4 is positioned below the first semiconductor layer and the second semiconductor layer (not shown), and the first gate electrode 112a and the second gate electrode 112b. To cover. The first electrode 118 is positioned on the gate insulating layer 116 of FIG. 4 and is in direct contact with the first drain electrode 134a of the first thin film transistor Tr1. As described above, the first electrode 118 has a plate shape in the pixel area P. FIG.

The protective layer 140 (refer to 140 in FIG. 4) is disposed under the second electrode 150 and covers the first and second thin film transistors Tr1 and Tr2 and the second drain electrode of the second thin film transistor Tr2. A drain contact hole 142 exposing 134b). The second electrode 150 is positioned on the passivation layer (140 of FIG. 4) and contacts the second drain electrode 134b of the second thin film transistor Tr2 through the drain contact hole 142.

6A through 6C are cross-sectional views illustrating a driving state of a liquid crystal display according to an exemplary embodiment of the present invention.

6A shows a white implementation. As shown in FIG. 6A, an electric field is not formed between the first to third electrodes 118, 150, and 160 in the first driving time, that is, in an off state, and the liquid crystal molecules of the liquid crystal layer 170 are not applied. 172 has an initial arrangement state. That is, as described above, the liquid crystal molecules 172 proximate to the first substrate 110 are arranged parallel to either one of the first polarization axis of the first polarizing plate 182 and the second polarization axis of the second polarizing plate 184. In addition, the liquid crystal molecules 172 adjacent to the second substrate 120 are arranged in parallel to the other of the first polarization axis of the first polarizing plate 182 and the second polarization axis of the second polarizing plate 184. That is, the liquid crystal molecules 172 are arranged in a twisted state by 90 degrees.

Therefore, the light supplied from the backlight unit (not shown) positioned below the first substrate 110 may be disposed in the first polarizer 182, the first substrate 110, the liquid crystal layer 170, the second substrate 120, and the like. The white state passes through the second polarizer 184. In this case, since the first to third electrodes 118, 150, and 160 are all made of a transparent conductive material, the transmittance is maximum.

That is, in the conventional normally black mode transverse electric field type liquid crystal display device, since the vicinity of the electrode cannot operate as an opening area when the liquid crystal is driven, there is a problem that the aperture ratio and the transmittance are lowered. However, in the liquid crystal display of the present invention, since the white state is obtained in the off state where no voltage is applied, the entire pixel region is used as the opening region, thereby improving the aperture ratio and transmittance. That is, in the first driving time, the first and second electrodes 118 and 150 are in a floating state, and no electric field is formed between the first and third electrodes 118, 150 and 160, and the liquid crystal molecules 172 maintains the initial arrangement.

6B shows the gray implementation state. As shown in FIG. 5B, the first voltage difference between the first and second electrodes 118 and 150 is generated in the second driving time, thereby forming the first electric field FE, which is a fringe field, thereby forming the liquid crystal molecules 172. While the 90 ° twisted state is driven, the liquid crystal molecules 172 are arranged along the direction of the electric field, thereby reducing the transmittance. Thus, gray implementations are possible. That is, an image having a second luminance smaller than the first luminance of the first driving time illustrated in FIG. 6A is implemented. In this case, the voltage of the third electrode 160 may be an average value of voltages applied to each of the first and second electrodes 118 and 150.

That is, referring to FIG. 5, when a gate signal is applied to the first gate electrode 114a through the first gate line 112a and the first thin film transistor Tr1 is turned on, through the first data line 130a. A first data signal is applied to the first electrode 118. In addition, when a gate signal is applied to the second gate electrode 114b through the second gate line 112b and the second thin film transistor Tr2 is turned on, the second data signal is transmitted through the second data line 130b. By being applied to the second electrode 150, a first voltage difference is generated between the first and second electrodes 118 and 150.

6C shows the black implementation. As shown in FIG. 5C, a second voltage difference greater than the first voltage difference is generated between the first and second electrodes 118 and 150 and the third electrode 160 at a third driving time, thereby generating a vertical electric field. Two electric fields VE are formed, thereby driving the liquid crystal molecules 172. That is, the long axis of the liquid crystal molecules 172 is arranged along the second electric field VE perpendicular to the first substrate 110, and the light provided from the backlight unit (not shown) is the second polarizing plate 184. It is blocked by and becomes black. In this case, since a uniform electric field is formed in the entire pixel region P and the liquid crystal molecules 172 are arranged vertically, an excellent black state can be displayed. That is, in the third driving time illustrated in FIG. 6C, an image having a third luminance smaller than the second luminance of the second driving time illustrated in FIG. 6B is implemented, and the third luminance becomes substantially zero. Therefore, a high quality image with improved contrast ratio can be realized.

In this case, referring to FIG. 5, when a gate signal is applied to the first gate electrode 114a through the first gate line 112a and the first thin film transistor Tr1 is turned on, through the first data line 130a. A third data signal is applied to the first electrode 118. In addition, when the gate signal is applied to the second gate electrode 114b through the second gate wire 112b and the second thin film transistor Tr2 is turned on, the third data signal is transmitted through the second data wire 130b. By being applied to the second electrode 150, the first and second electrodes 118 and 150 are in an equipotential state. That is, the same voltage is applied to the first and second electrodes 118 and 150.

In addition, a signal different from the third data signal is applied to the third electrode 160 such that a second voltage difference greater than the first voltage difference is provided between the first and second electrodes 118 and 150 and the third electrode. By generating, the second electric field VE is formed. As described above, the third electrode 160 is formed on the entire second substrate 120 and is always in the same voltage.

Meanwhile, an electric field may be formed only between the first and third electrodes 118 and 160 while no voltage is applied to the second electrode 150.

That is, in the driving state shown in FIG. 5B, the liquid crystal close to the second substrate 120 may not have a state parallel to the second substrate 120 because the first electric field FE is weak. Therefore, even when driven by a high voltage, light leaks and a sufficient black state cannot be obtained. However, as shown in FIG. 5C, in the present invention, a sufficient black state can be obtained by being driven by the second electric field VE perpendicular to the first and second substrates 110 and 120 in the high voltage driving state.

7A and 7B are graphs showing simulation results of driving voltage and transmittance of a liquid crystal display according to an exemplary embodiment of the present invention.

FIG. 7A is a simulation result of the second driving time described with reference to FIG. 6B, and FIG. 7B is a simulation result of the third driving time described with reference to FIG. 6C.

7A shows a case A in which a first alignment layer is oriented parallel to the gate wiring and a second alignment layer is oriented perpendicular to the gate wiring, and a case in which the first alignment film is oriented perpendicular to the gate wiring and the second alignment film is oriented parallel to the gate wiring. Shows B As shown in FIG. 7A, the liquid crystal molecules are driven by the fringe fields formed between the first and second electrodes 118 and 150, and the transmittance is decreased by increasing the driving voltage.

In FIG. 7B, the graphs of case A and case B overlap. As shown in FIG. 7A, the liquid crystal molecules are driven by the vertical electric field, and the transmittance becomes substantially zero by increasing the driving voltage.

Therefore, as in the present invention, a white image is provided during the first driving time when no electric field is formed, and between the first and second electrodes 118 and 150 formed on the first substrate 110 during the second driving time. The gray image is provided by the formed fringe field, and a black image is provided by a vertical electric field perpendicular to the first and second substrates 110 and 120 at the third driving time.

Therefore, sufficient brightness and contrast ratio can be obtained. In addition, the entire pixel area P may be used as an opening area without limitation of the first to third electrodes 118, 150, and 160 during the first driving time for providing a white image.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art various modifications and changes of the present invention without departing from the spirit and scope of the present invention described in the claims below I can understand that you can.

118: first electrode
150: second electrode
160: third electrode
170: liquid crystal layer
182: first alignment layer
184: second alignment layer

Claims (9)

A first substrate on which a plurality of pixel regions are defined;
A first electrode positioned inside each of the plurality of pixel regions and having a plate shape inside the first substrate;
A protective layer covering the first electrode;
A second electrode on each of the plurality of pixel regions on the passivation layer, the second electrode having at least one opening with respect to the first electrode;
A second substrate facing the first substrate;
A third electrode disposed inside the second substrate and covering the entire pixel area;
A liquid crystal layer positioned between the second electrode and the third electrode
Liquid crystal display comprising a.
The method of claim 1,
A first polarizing plate positioned outside the first substrate and having a first transmission axis;
And a second polarizing plate positioned outside the second substrate and having a second transmission axis perpendicular to the first transmission axis.
The method of claim 2,
A first alignment layer positioned between the second electrode and the liquid crystal layer and parallel to any one of the first transmission axis and the second transmission axis;
And a second alignment layer disposed between the third electrode and the liquid crystal layer and parallel to another one of the first transmission axis and the second transmission axis.
The method of claim 3, wherein
First and second gate lines spaced apart from each other in parallel;
First and second data lines crossing the first and second gate lines and spaced apart in parallel;
A first thin film transistor connected to the first gate line and the first data line;
A second thin film transistor connected to the second gate line and the second data line;
And the first electrode is connected to the first thin film transistor, and the second electrode is connected to the second thin film transistor.
The method of claim 4, wherein
Each of the first and second thin film transistors includes a gate electrode, a semiconductor layer, a source electrode, and a drain electrode.
Gate electrodes of the first and second thin film transistors are respectively connected to the first and second gate wirings, and source electrodes of the first and second thin film transistors are respectively connected to the first and second data wirings, And the first electrode is in direct contact with the drain electrode of the first thin film transistor, and the second electrode is in contact with the drain electrode of the second thin film transistor through a contact hole formed in the protective layer.
The method of claim 1,
And each of the first to third electrodes is made of a transparent conductive material.
A first substrate on which a plurality of pixel regions are defined; A first electrode positioned inside each of the plurality of pixel regions and having a plate shape inside the first substrate; A second electrode having at least one opening with respect to said first electrode; A second substrate facing the first substrate; A third electrode disposed inside the second substrate and covering the entire pixel area; In the liquid crystal display device including a liquid crystal layer positioned between the second electrode and the third electrode,
Floating the first and second electrodes to display an image of a first luminance;
Displaying an image of a second luminance smaller than the first luminance by generating a first voltage difference between the first and second electrodes to drive the liquid crystal layer;
Displaying an image of a third luminance smaller than the second luminance by driving the liquid crystal layer by generating a voltage difference greater than the first voltage difference between the first and third electrodes.
Method of driving a liquid crystal display device comprising a.
The method of claim 7, wherein
In the displaying of the image of the second brightness, the average value of the voltage applied to each of the first and second electrodes is the same as the voltage applied to the third electrode.
The method of claim 7, wherein
The displaying of the image of the third luminance may include applying a voltage equal to a voltage applied to the first electrode to the second electrode.

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