KR101386576B1 - Liquid crystal display panel - Google Patents

Abstract

The liquid crystal display panel of the present invention further minimizes the leakage current of the antistatic circuit by the backlight light reflected by the black matrix by additionally configuring the color filter on the upper color filter substrate corresponding to the antistatic circuit. An array substrate and a color filter substrate divided into outer portions; An antistatic circuit formed on an outer periphery of the array substrate to disperse overvoltage; A black matrix formed on the color filter substrate to block leakage of backlight light; A color filter formed to extend to the outer periphery of the pixel of the color filter substrate on which the antistatic circuit is located to minimize the incidence of backlight light reflected by the black matrix into the antistatic circuit; And a liquid crystal layer formed between the array substrate and the color filter substrate.

Antistatic Circuit, Color Filter, Black Matrix, Backlight Light, Leakage Current

Description

Liquid Crystal Display Panel {LIQUID CRYSTAL DISPLAY PANEL}

The present invention relates to a liquid crystal display panel, and more particularly, to a liquid crystal display panel having an antistatic circuit for minimizing damage caused by static electricity.

2. Description of the Related Art In general, a liquid crystal display device is a display device that displays a desired image by individually supplying data signals according to image information to pixels arranged in a matrix form and adjusting the light transmittance of the pixels.

To this end, the liquid crystal display device includes a liquid crystal display panel in which pixels are arranged in a matrix form, and a driver for driving the pixels.

In the liquid crystal display panel, an array substrate on which a thin film transistor array is formed and a color filter substrate on which a color filter is formed are bonded together to maintain a uniform cell gap, A liquid crystal layer is formed in the cell gap between the electrodes.

At this time, an alignment film is formed on the surface of the array substrate opposite to the color filter substrate, and rubbing is performed so that the liquid crystal of the liquid crystal layer is aligned in a predetermined direction.

In addition, the array substrate and the color filter substrate are bonded by a seal line formed along the outer edge of the pixel portion, and the outer surface of the bonded array substrate and the color filter substrate is provided with a polarizing plate and a phase difference plate. By selectively configuring the elements, a liquid crystal display panel having high luminance and contrast characteristics is formed by changing the traveling state of the light or changing the refractive index.

Hereinafter, a liquid crystal display panel configured as above will be described in detail with reference to the drawings.

1 is a plan view schematically illustrating an array substrate structure of a general liquid crystal display panel.

As shown in the drawing, the array substrate 10 including the driving unit includes a pixel unit 11 in which pixels P1 are arranged in a matrix form to display an image, and a gate line 16 of the pixel unit 11. And a gate driver 26 connected to the data lines and a data driver 27 connected to the data lines 17.

In this case, although not shown in the drawing, the gate pad portion and the data pad portion are formed in an edge region of the array substrate 10 that does not overlap with the color filter substrate (not shown), and the gate pad portion is supplied from the gate driver 26. The scan signal is supplied to the gate lines 16 of the pixel unit 11, and the data pad unit supplies the image information supplied from the data driver 27 to the data lines 17 of the pixel unit 11.

In addition, in the pixel portion 11 of the array substrate 10, the data lines 17 to which image information is applied and the gate lines 16 to which a scan signal is applied are arranged to intersect with each other. Thin film transistors (not shown) and pixel electrodes (not shown) are respectively provided in regions partitioned by the gates and the gate lines 16.

Although not shown in the drawing, the color filter substrate includes color filters partitioned by pixels by a black matrix and a common electrode that is a counter electrode of the pixel electrode formed on the array substrate 10. do.

The liquid crystal display device configured as described above is a holding display device, and when the high potential scan signal of the gate driver is sequentially applied to each gate line, image information applied to the pixel through the data line. Is applied to the pixel electrode. As a result, an electric field is applied to the liquid crystal layer by the voltage difference between the pixel electrode and the common electrode, and the storage capacitor is charged with the storage capacity. This storage capacity maintains the luminance by maintaining the arrangement of liquid crystal molecules for one frame when the scan signal transitions to a low potential.

As described above, the liquid crystal display is driven by a voltage driving method, and the arrangement of the liquid crystals is changed by the voltage difference between the voltage according to the magnitude of the image information applied to the pixel electrode and the common voltage applied to the common electrode. By adjusting the transmission, an image is displayed. As a result, it can be driven sensitively to external or internal voltage changes, and the elements inside the liquid crystal display can be destroyed by static electricity or internal abnormal overvoltage, which can occur around the surroundings. The problem of deterioration of the image quality will occur.

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 panel having an antistatic circuit for preventing damage caused by static electricity generated from outside or inside.

Another object of the present invention is to provide a liquid crystal display panel which minimizes the leakage current of the antistatic circuit by the backlight light reflected by the black matrix.

Other objects and features of the present invention will be described in the following description of the invention and claims.

In order to achieve the above object, the liquid crystal display panel of the present invention includes an array substrate and a color filter substrate divided into a pixel portion and a pixel outer portion; An antistatic circuit formed on an outer periphery of the array substrate to disperse overvoltage; A black matrix formed on the color filter substrate to block leakage of backlight light; A color filter formed to extend to the outer periphery of the pixel of the color filter substrate on which the antistatic circuit is located to minimize the incidence of backlight light reflected by the black matrix into the antistatic circuit; And a liquid crystal layer formed between the array substrate and the color filter substrate.

As described above, the liquid crystal display panel according to the present invention can reduce the luminance of the backlight light reflected by the black matrix by about 1/12 by forming a color filter on the antistatic circuit. As a result, as the leakage current of the antistatic circuit due to the reflected light is minimized, the image quality is improved and power consumption is reduced.

In addition, the liquid crystal display panel according to the present invention provides an advantage of stabilizing the common voltage and maintaining the cell gap uniformly.

Hereinafter, exemplary embodiments of the liquid crystal display panel method according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a plan view schematically illustrating an array substrate structure of a liquid crystal display panel according to an exemplary embodiment of the present invention.

As shown in the drawing, an array substrate 110 including a driving unit according to an exemplary embodiment of the present invention includes a pixel unit 111 and a pixel unit 111 in which pixels P1 are arranged in a matrix to display an image. The gate driver 126 is connected to the gate lines 116 and the data driver 127 is connected to the data lines 117.

In this case, although not shown in the drawing, the gate pad portion and the data pad portion are formed in an edge region of the array substrate 110 that does not overlap with the color filter substrate (not shown), and the gate pad portion is supplied from the gate driver 126. The scan signal is supplied to the gate lines 116 of the pixel unit 111, and the data pad unit supplies the image information supplied from the data driver 127 to the data lines 117 of the pixel unit 111.

In addition, data lines 117 to which image information is applied and gate lines 116 to which a scan signal is applied are arranged in the pixel portion 111 of the array substrate 110 to intersect the data line 117. ) And a thin film transistor (not shown) and a pixel electrode (not shown) are respectively provided in regions partitioned by the gate lines 116 and the gate lines 116.

Although not shown in the drawing, the color filter substrate includes color filters partitioned by pixels by a black matrix and a common electrode which is a counter electrode of the pixel electrode formed on the array substrate 110.

Here, the array substrate 110 of the liquid crystal display panel according to the embodiment of the present invention is a common voltage line 118 and the common voltage line 118 for supplying a common voltage Vcom to the common electrode of the color filter substrate. And an antistatic circuit 130 connected to the gate line 116 and the data line 117 to distribute the overvoltage.

In this case, the common voltage line 118 is patterned along the outer side of the array substrate 110, and the common voltage Vcom supplied to the common voltage line 118 is the outer side of the array substrate 110. Silver dots (not shown) formed at corners are applied to the common electrode of the color filter substrate.

As described above, an antistatic circuit 130 is connected to one side of the gate line 116 and the data line 116, and the gate line 116 and the data line 116 are connected to the antistatic circuit 130. The common voltage line 118 is connected to the other side that is not.

The antistatic circuit 130 may not operate normally, but when static electricity or the like is introduced to the gate line 116 and the data line 116, an overcurrent caused by a high voltage flows in the antistatic circuit 130. Over current flows in the gate line 116 and the data line 116 through the common voltage line 118. In other words, by distributing the overcurrent generated in one line to all the lines to minimize the damage caused by static electricity.

For reference, FIG. 3 is a circuit diagram illustrating the antistatic circuit shown in FIG. 2 as an example, and illustrates an antistatic circuit 130 configured using three thin film transistors between the data line 117 and the common line. It is shown.

At this time, the antistatic circuit 130 located outside the pixel unit 111 of the array substrate 110 generates a leakage current by backlight light reflected by the black matrix of the upper color filter substrate, thereby increasing the current consumption and the common voltage (Vcom). Increasing the load of) will affect the image quality.

As described above, in order to prevent leakage current from occurring in the antistatic circuit 130 due to the reflected light, the color filter substrate according to the embodiment of the present invention may include the pixel portion of the array substrate 110 in which the antistatic circuit 130 is located. 111) By extending the color filter to the outside, it is possible to minimize the leakage current of the antistatic circuit 130, which will be described in detail with reference to the accompanying drawings.

FIG. 4 is a cross-sectional view schematically illustrating a structure of a liquid crystal display panel according to an exemplary embodiment of the present invention, and illustrates one thin film transistor among antistatic circuits formed at an outer portion of the pixel unit.

As shown in the drawing, the liquid crystal display panel is largely bonded to the array substrate 110 on which the thin film transistor array is formed and the color filter substrate 105 on which the color filter 107 is formed so that a uniform cell gap is maintained. The liquid crystal layer is formed in the cell gap between the 110 and the color filter substrate 105.

In this case, although not shown in the drawing, the array substrate 110 of the pixel unit 110 may include a gate line to which a scan signal is applied from an external driving circuit, a data line to which an image signal is applied, and a switch formed at an intersection of the gate line and the data line. And a pixel electrode connected to the thin film transistor.

In addition, an antistatic circuit according to an exemplary embodiment of the present invention, which is connected to a common voltage line (not shown) and the gate line and the data line to distribute overvoltage, is formed on the array substrate 110 outside the pixel portion. Similarly, the drawing shows one thin film transistor constituting the antistatic circuit, for example.

In this case, the thin film transistor includes a gate electrode 121, a source electrode 122, and a drain electrode 123. In addition, the thin film transistor may include the first insulating film 115a for insulation between the gate electrode 121 and the source / drain electrodes 122 and 123 and the source electrode by a gate voltage supplied to the gate electrode 121. And a semiconductor layer 124 forming a conductive channel between the 122 and the drain electrode 123.

For reference, reference numerals 115b and 125 denote a second insulating film and an ohmic contact layer, respectively, and this configuration is substantially the same as that of the thin film transistor of the pixel portion.

Although not shown in the drawing, a black matrix 106, a color filter 107, and a common electrode are formed on the color filter substrate 105 of the pixel portion, and the black matrix 106 is patterned on the boundary region of the pixels. It blocks the leakage of light generated from the backlight (not shown) and prevents the mixing of adjacent pixels. In addition, the color filter 107 of the pixel portion is partially overlapped with the black matrix 106 and formed to correspond to the unit pixel, and the red (R), green (G), and blue (B) sub colors are formed. -Consists of color filter.

In addition, the black matrix 106 for blocking the backlight light incident from the bottom and the backlight light reflected by the black matrix 106 are incident on the color filter substrate 105 outside the pixel portion to the antistatic circuit. In order to minimize, a color filter 107 extending from the pixel portion is formed. At this time, the color filter 107 outside the pixel unit prevents the backlight light reflected by the black matrix 106 from being incident on the thin film transistor of the antistatic circuit, that is, the back channel of the thin film transistor. Leakage current can be minimized.

In addition, an overcoat layer 109 may be formed on the black matrix 106 and the color filter 107, and the overcoat layer 109 is formed of the black matrix 106 and the color filter 107. It serves to planarize the upper surface of the).

As described above, in the exemplary embodiment of the present invention, the pigment region of the color filter is expanded to the outside of the pixel portion where the antistatic circuit is configured, thereby minimizing the leakage current of the antistatic circuit due to the internal reflection of the black matrix. The luminance of the backlight light reflected by the matrix can be reduced by, for example, 1/12.

As a result, as the leakage current of the antistatic circuit due to the reflected light is minimized, the image quality is improved and power consumption is reduced. In addition, the antistatic circuit according to the embodiment of the present invention, which minimizes the leakage current, provides the advantage of maintaining the cell gap uniformly while the common voltage is stabilized. That is, since the color filter of the pixel unit extends to the outside of the pixel unit where the antistatic circuit is configured, the cell gap between the pixel unit and the outside of the pixel unit can be maintained uniformly.

FIG. 5 is a table showing the results of measuring the luminance of the backlight light reflected by the black matrix. FIG. 5 shows the result of the reflection of the reflected light with respect to the luminance of the backlight light in the absence of the color filter pigment, the red color, the blue color, and the green color. The result of measuring luminance is shown, for example.

In this case, the luminance of the backlight light reflected by the black matrix in each case is shown with the luminance of the backlight light being 4000, 7000, 10000, 15000 and 20000 nits.

As shown in the figure, the luminance of the backlight light reflected by the black matrix is 65 to 326 nit, 57 to 283 nit, and 414 to 2068 when the color filter pigment is red, blue, and green, respectively. It can be seen that the nit is significantly reduced compared to the absence of color filter pigments (776 ~ 3881 nit).

For reference, the luminance represents the degree of light emitted at a light intensity per apparent unit area of the object seen from the outside. In other words, it is the amount of light reflected by the light of a light source touching a surface, and a unit of stilbe or nitrile is used to represent luminance.

In particular, it can be seen that when the red and blue pigments are used as the color filter pigments, the luminance of the reflected light is significantly reduced.

Accordingly, the outer edge of the pixel portion of the present invention may configure a color filter using only red or blue pigments, or may overlap the red and blue pigments. Of course, in order to simplify the process, red, green, and blue may be sequentially configured in the same way as the pixel portion.

The manufacturing method of the liquid crystal display panel according to the embodiment of the present invention configured as described above is largely an array process for forming an array substrate, a color filter process for forming a color filter substrate, and a unit liquid crystal by combining the array substrate and the color filter substrate. The cell process is performed to form a display panel, which will be described in more detail as follows.

First, a plurality of gate lines and data lines arranged vertically and horizontally on a transparent insulating substrate such as glass to define a plurality of pixel regions are formed in the pixel portion of the array substrate, and connected to the gate lines and the data lines in the respective pixel regions. A thin film transistor which is a switching element is formed.

In this case, an antistatic circuit formed of a predetermined thin film transistor is formed outside the pixel portion of the array substrate. In addition, the pixel electrode is connected to the thin film transistor of the pixel unit through the array process and drives the liquid crystal layer as a signal is applied through the thin film transistor.

In addition, the pixel portion of the color filter substrate distinguishes between a color filter composed of a sub-color filter that implements red, green, and blue colors by the color filter process and the sub-color filter, and blocks light that passes through the liquid crystal layer. Form a black matrix. In this case, a color filter extending from the pixel portion is formed outside the pixel portion of the color filter substrate in which the antistatic circuit is located to minimize the incidence of backlight light reflected by the black matrix into the antistatic circuit.

The black matrix may be an organic film made of a resin material, for example, colored acrylic, epoxy, or polyimide resin including any one of carbon black and black pigment. Organic resin etc. can be applied.

Next, an overcoat layer made of a transparent insulating material may be formed on the entire surface of the color filter substrate. The overcoat layer may be formed of a transparent resin having insulating properties to planarize the substrate on which the color filter is formed and to prevent elution of the pigment ions, and may be formed of an acrylic resin or an epoxy resin.

In this case, when the organic film made of a resin material is applied to the black matrix, the overcoat layer is formed to prevent driving failure of the liquid crystal layer due to the step difference in the region where the black matrix and the color filter overlap. However, the present invention is not limited thereto, and when the color filter corresponding to the pixels is formed so as not to overlap the black matrix, an additional overcoat layer for surface planarization is not required.

Next, a spacer is formed of an organic layer on the color filter substrate or the array substrate. The spacer may be a column spacer (or a patterned spacer) that is fixed to an array substrate or a color filter substrate as the liquid crystal display panel is gradually enlarged.

Subsequently, an alignment layer is applied to the array substrate and the color filter substrate, respectively, and then the alignment layer is provided to provide alignment control force or surface fixation force (ie, pretilt angle and alignment direction) to the liquid crystal molecules of the liquid crystal layer formed between the two substrates. Orientation treatment.

Next, a predetermined seal line is formed on the color filter substrate with a sealant, and a liquid crystal layer is formed on the array substrate.

At this time, the method of forming the liquid crystal layer is largely divided into a vacuum injection method and a dropping method, which will be described in detail as follows.

First, in the vacuum injection method, the liquid crystal inlet of the unit liquid crystal display panel separated from the mother substrate of a large area is immersed in a container filled with liquid crystal in a chamber in which a constant vacuum is set, and then the degree of vacuum is changed. The liquid crystal is injected into the liquid crystal display panel by an external pressure difference. When the liquid crystal is filled in the liquid crystal display panel in this manner, the liquid crystal inlet is sealed to form the liquid crystal layer of the liquid crystal display panel. Accordingly, when the liquid crystal layer is formed on the liquid crystal display panel through the vacuum injection method, a part of the seal line should be opened so as to function as a liquid crystal injection hole.

However, the vacuum injection method as described above has the following problems.

First, the time required to fill the liquid crystal display panel with the liquid crystal is very long. In general, since the bonded liquid crystal display panel has a gap of several μm in an area of several hundred cm 2, even if a vacuum injection method using a pressure difference is applied, the amount of liquid crystal injected per unit time is very small. For example, when manufacturing a liquid crystal display panel of about 15 inches takes about 8 hours to fill the liquid crystal there is a problem that the production of the liquid crystal display panel takes a lot of time, productivity is lowered. Further, as the size of the liquid crystal display panel is increased, the time required for filling the liquid crystal becomes longer and the filling failure of the liquid crystal is generated. As a result, the liquid crystal display panel can not be increased in size.

Second, the consumption of liquid crystal is high. In general, the amount of liquid crystal actually injected into the liquid crystal display panel is very small compared to the amount of liquid crystal filled in the container, and when the liquid crystal is exposed to the atmosphere or a specific gas, it reacts with the gas and deteriorates. Therefore, even if the liquid crystal filled in the container is filled in a plurality of liquid crystal display panels, a large amount of liquid crystals remaining after the filling should be discarded. As such, the expensive liquid crystals are discarded, resulting in an increase in the cost of the liquid crystal display panel. It is a factor that weakens the price competitiveness of the product.

In order to overcome the problems of the vacuum injection method as described above, the dropping method has been recently applied.

The dropping method uses a dispenser to drop and dispense liquid crystals in an image display area of a first large substrate having a plurality of array substrates or a second mother substrate having a plurality of color filter substrates disposed thereon. The liquid crystal layer is formed by uniformly distributing the liquid crystals to the entire image display area by the pressure for bonding the first and second mother substrates together.

Therefore, when the liquid crystal layer is formed on the liquid crystal display panel by a dropping method, the seal line should be formed in a closed pattern surrounding the outer edge of the image display area to prevent the liquid crystal from leaking out of the image display area.

The dropping method can drop the liquid crystal in a short time compared to the vacuum injection method, and even when the liquid crystal display panel is enlarged, the liquid crystal layer can be formed very quickly.

In addition, since only the required amount of liquid crystal is dropped on the substrate, the price competitiveness of the liquid crystal display panel due to the disposal of expensive liquid crystal, such as a vacuum injection method, is prevented, thereby enhancing the price competitiveness of the product.

Unlike the vacuum injection method, the liquid crystal display panel to which the drop method is applied has a process of separating the unit liquid crystal panel from the large area mother substrate after the liquid crystal layer is formed.

Thereafter, pressure is applied to the array substrate and the color filter substrate to form a unit liquid crystal display panel.

Meanwhile, in order to improve the yield in manufacturing the unit liquid crystal display panel as described above, a method of simultaneously forming a plurality of unit liquid crystal display panels on a large area mother substrate is generally applied. Accordingly, there is a need for a process of cutting and processing a mother substrate on which a plurality of liquid crystal display panels are manufactured to separate a unit liquid crystal display panel from a large area mother substrate.

Thereafter, the liquid crystal display panel is manufactured by inspecting the liquid crystal display panels.

While a great many are described in the foregoing description, it should be construed as an example of preferred embodiments rather than limiting the scope of the invention. Therefore, the invention should not be construed as limited to the embodiments described, but should be determined by equivalents to the appended claims and the claims.

1 is a plan view schematically showing an array substrate structure of a general liquid crystal display panel.

2 is a plan view schematically illustrating an array substrate structure of a liquid crystal display panel according to an exemplary embodiment of the present invention.

3 is a circuit diagram showing an example of the antistatic circuit shown in FIG. 2;

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

5 is a table showing the results of measuring the luminance of the backlight light reflected on the black matrix.

DESCRIPTION OF REFERENCE NUMERALS

105: color filter substrate 106: black matrix

107: color filter 110: array substrate

111: pixel portion 116: gate line

117: data line 118: common voltage line

130: antistatic circuit

Claims (7)

An array substrate and a color filter substrate divided into a pixel portion and a pixel outer portion; An antistatic circuit formed on an outer periphery of the array substrate to disperse overvoltage; A black matrix formed on the color filter substrate to block leakage of backlight light; A color filter formed to extend to the outer periphery of the pixel of the color filter substrate on which the antistatic circuit is located to minimize the incidence of backlight light reflected by the black matrix into the antistatic circuit; And And a liquid crystal layer formed between the array substrate and the color filter substrate. 2. The liquid crystal display panel of claim 1, wherein the color filter of the pixel portion comprises a sub-color filter of red, green, and blue. The liquid crystal display panel of claim 2, wherein the color filter of the pixel outer portion includes only the red or green sub-color filters. The liquid crystal display panel of claim 2, wherein the color filter of the pixel outer portion is formed by overlapping the red or green sub-color filters. 3. The liquid crystal display panel of claim 2, wherein the color filter of the pixel outer portion comprises the red, green, and blue sub-color filters in the same way as the pixel portion. The method of claim 1, further comprising: a gate line to which a scan signal is applied, an data line to which an image signal is applied, and a common voltage line to which a common voltage is formed, formed in the pixel portion of the array substrate. A liquid crystal display panel characterized by the above. 7. The liquid crystal display panel of claim 6, wherein the antistatic circuit is connected to the common voltage line, the gate line, and the data line to disperse overvoltage.

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