KR100783703B1 - Liquid crystal display panel and liquid crystal display device with the same - Google Patents

Abstract

The present invention provides a liquid crystal display panel having a storage capacitor having an independent wiring structure and a liquid crystal display device having the same.

According to the liquid crystal display panel of the present invention, a plurality of data lines for transmitting an image signal, a plurality of gate lines for transmitting a scan signal, are connected to the gate line through a first end, and a data line through a second end And a storage element connected to the third end of the switching element, and a storage element connected to the third end of the switching element, and the other end of the storage capacitor arranged in a horizontal direction. Independent wiring is connected to the other end of at least one adjacent storage capacitor.

As a result, even in the manufacturing process of the liquid crystal display panel, even if line damage occurs between the storage capacitor line arranged in the horizontal direction and the gate line arranged in the horizontal direction, this can be detected more easily, and the detected line damage can be more easily corrected. Can be.

LCD, line damage, storage capacitor, liquid crystal display panel, independent wiring

Description

Liquid crystal display panel and liquid crystal display device having the same {LIQUID CRYSTAL DISPLAY PANEL AND LIQUID CRYSTAL DISPLAY DEVICE WITH THE SAME}

1 is a view for explaining an equivalent circuit of a liquid crystal display panel having a general independent wiring system.

2 is a diagram for describing line damage occurring in a general liquid crystal display panel.

3A and 3B are diagrams for describing pixel voltages when data voltages applied to a normal pixel are 9.5V and 0V, respectively.

4A and 4B are diagrams for describing a pixel voltage when data voltages of a pixel damaged by lines are 9.5V and 0V.

5 is a view for explaining a liquid crystal display having a storage capacitor having an independent wiring structure according to the present invention.

FIG. 6 is a diagram illustrating line damage that may occur in a liquid crystal display panel according to an exemplary embodiment of the present invention.

FIG. 7 is a diagram for describing line damage that may occur in a liquid crystal display panel according to another exemplary embodiment.

8 is a view for explaining another embodiment of the present invention.                 

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

100: timing controller 200: driving voltage generator

300: data driver 400: gate driver

500: liquid crystal display panel

The present invention relates to a liquid crystal display panel and a liquid crystal display device having the same, and more particularly, to a liquid crystal display panel having a storage capacitor having an independent wiring structure and a liquid crystal display device having the same.

In general, an LCD applies an electric field to a liquid crystal material having an anisotropic dielectric constant injected between two substrates, and adjusts the intensity of the electric field to adjust the amount of light transmitted through the substrate to obtain a desired image signal. to be.

Such LCDs are typical among portable flat panel display devices. Among them, TFT-LCDs using thin film transistors (TFTs) as switching elements are mainly used.

On the other hand, as the LCD changes in high resolution, the RC delay of the gate line becomes a problem, and thus the structure of the storage capacitor is formed by a common independent wiring method.

1 is a view for explaining an equivalent circuit of a general liquid crystal display panel.

Referring to FIG. 1, all the storage capacitors of the TFT-LCD are connected by one common independent wiring so that the reference potential of the storage capacitor Cst, which is the storage capacitor, can be externally applied.

However, since the common independent wiring method connects the entire storage capacitors arranged in the horizontal direction to a predetermined common independent wiring, a short occurs between the common independent wiring and the gate lines disposed adjacent thereto, and thus line damage may occur. Lots of possessions.

2 is a diagram for describing line damage occurring in a general liquid crystal display panel.

As shown in FIG. 2, since the independent wiring and the gate line of the storage capacitor Cst are arranged adjacent to each other in the same layer of the same metal material on the liquid crystal display panel, a short circuit occurs between the lines. As described above, there is a problem in that the yield of the liquid crystal display panel is lowered due to short between lines or line defects.

3A and 3B are diagrams for explaining the pixel voltage Vp when the data voltage Vd applied to a normal pixel is 9.5V and 0V, respectively, and FIGS. 4A and 4B are FIGS. ) Is a diagram for explaining the pixel voltage Vp when the data voltages Vd are 9.5V and 0V in a pixel damaged by a line.

As shown in (a) and (b) of FIG. 3, in the case of a normal pixel which is not damaged between the common independent wiring and the gate line, the positive data voltage (9.5V) and It can be seen that inversion is performed when a negative data voltage (0V) is applied.

However, as shown in (a) and (b) of FIG. 4, in a liquid crystal display panel having a storage capacitor having a common independent wiring structure, when line damage occurs between the common independent wiring and the gate line connecting the storage capacitor, the storage is performed. The capacitor operates as if it is a parasitic capacitor Cgs present at the gate and source terminals of the TFT.

That is, when the on / off of the gate voltage Vg is changed, an extreme feedthrough voltage drop occurs, and the pixel voltage Vp applied to the pixel drops to -10 volts or less. Therefore, the pixel is displayed as abnormally dark black on the screen.

The line damage of the liquid crystal display panel having such a storage structure of a common independent wiring structure is displayed as horizontal line damage in a type that occurs in the range of 5 to 10% in the actual production line.

In particular, when such a display type occurs, it appears as a line damage all over one gate line, and thus it is difficult to find a corresponding defective position and restore it using a laser or the like. This is because, if the resolution of the liquid crystal display panel is XGA, the line damage block must be checked for each of 1024 * 3 data lines and for UXGA for 1600 * 3 data lines.

In addition, there is a problem that the production yield is lowered due to the difficulty of such restoration.

Accordingly, the present invention has been made in an effort to solve such a conventional problem, and an object of the present invention is to independently reduce line damage occurring between a storage capacitor connection line and a gate line in a liquid crystal display panel having a storage capacitor. It is to provide a liquid crystal display panel having a storage capacitor having a wiring structure.

Another object of the present invention is to provide a liquid crystal display device having the above liquid crystal display panel.

According to one aspect of the present invention, a liquid crystal display panel includes: a plurality of data lines for transmitting an image signal;

A plurality of gate lines transmitting scan signals;

A switching element connected to the gate line through a first stage and connected to a data line through a second stage; And

A liquid crystal capacitor connected to the third end of the switching element, and a storage capacitor connected to the third end of the switching element through one end,

The other end of the storage capacitor arranged in the horizontal direction is connected to the other end of at least one adjacent storage capacitor by an independent wiring. Here, the storage capacitor is preferably connected to each other in a pair of 2N (where N is an integer) through the other end, and the number of data lines is a multiple of the 2N (where N is an integer). desirable.

In addition, the positive charge amount and the negative charge amount of the liquid crystal capacitor connected to the storage capacitor are preferably the same, and it is preferable that a voltage is not applied from the outside to the independent wiring connecting the other ends of the storage capacitor.

In addition, the independent wiring and the gate line connecting the other ends of the storage capacitor are preferably located on the same plane, and the independent wiring and the gate line connecting the other ends of the storage capacitor are preferably formed of the same metal material.

In addition, it is preferable that the charging polarity of the liquid crystal capacitor connected to the connected storage capacitor is different from the charging polarity of the capacitance of the adjacent liquid crystal capacitor. It is preferable.

On the other hand, the liquid crystal display device according to one feature for realizing another object of the present invention described above,

A timing controller configured to output a first control signal for outputting a scan signal and a second control signal for outputting an image signal;

A scan driver configured to output a scan signal based on the first control signal;

An image driver for outputting an image signal based on the second control signal; And

A plurality of data lines for transmitting the image signal, a plurality of gate lines for transmitting the scan signal, a switching element connected to the gate line through a first stage and a data line through a second stage, and A liquid crystal display panel having a liquid crystal capacitor connected to a third end of the switching element, and a storage capacitor connected to the third end of the switching element through one end thereof;

The other end of the storage capacitor arranged in the horizontal direction is connected to the other end of at least one adjacent storage capacitor by an independent wiring.

According to the liquid crystal display panel having the storage capacitor of the independent wiring structure and the liquid crystal display device having the same, line damage occurs between the storage capacitor line arranged in the horizontal direction and the gate line arranged in the horizontal direction in the manufacturing process of the liquid crystal display panel. Even if this is more easily detected, correction of the detected line damage can be performed more easily.

Then, embodiments will be described so that those skilled in the art can easily implement the present invention.

5 is a view for explaining a liquid crystal display having a storage capacitor having an independent wiring structure according to the present invention.

Referring to FIG. 5, a liquid crystal display having a storage capacitor having an independent wiring structure according to the present invention includes a timing controller 100, a driving voltage generator 200, a data driver 300, a gate driver 400, and a liquid crystal display. Panel 500.

The timing controller 100 controls the R, G, and B data signals R (0: N), G (0: N), and B (0: N) from a graphic controller (not shown) outside the LCD module. The vertical synchronization signal Vsync as the discrimination signal, the horizontal sync signal Hsync as the line discrimination signal, the data enable signal DE and the main which are high level only during the period in which the data is output to indicate the area where the data enters. Each of the clock signals MCLK is provided to output a digital signal for driving the driving voltage generator 200, the data driver 300, and the gate driver 400.                     

In more detail, the timing controller 100 starts inputting the digital data signals R (0: N), G (0: N), and B (0: N) from the graphics controller to the data driver 300. A signal STH commanding the signal, a signal LOAD commanding the data to be applied to the LCD panel 500, and a clock signal HCLK for shifting data in the data driver 300 to the data driver 300. Output

In addition, the timing controller 100 performs a vertical line start signal STV for commanding the start of the gate on signal, and a gate clock signal Gate clk for sequentially performing the gate on signal on each gate line. Output to

That is, a digital signal for driving the data driver 300 and the gate driver 400 is generated and output to the corresponding drivers 300 and 400.

The driving voltage generator 200 is a reference for the voltage Von for making the gate-on signal, the voltage Voff for making the gate-off signal, and the data voltage difference in the LCD panel 500, and more specifically, the TFT-LCD panel. This common voltage Vcom is output to the gate driver 400. In the exemplary embodiment of the present invention, the application of the common voltage is described as being applied by the driving voltage generator. However, the application of the common voltage may be output from other external components.

The data driver 300 receives R, G, and B digital data (R (0: N), G (0: N), and B (0: N)) from the timing controller 100 and stores the received digital data. When a load signal LOAD for commanding the panel 500 is applied, the voltage corresponding to each data is selected to apply the data voltages D1, D2, D3,..., And Dm to the LCD panel 500. To pass. Of course, the data driver 300 outputs data voltages D1, D2, D3,..., Dm so that the polarities of the pixels arranged on the LCD panel 500 are inverted different from each other in each frame. In this case, the inversion of the pixels so that the polarities are different every frame is due to the general characteristics of the liquid crystal, as is already known.

The gate driver 400 receives a gate clock signal Gate clk and a vertical line start signal STV from the timing controller 100, including a shift register, a level shifter, a buffer, and the like, and the driving voltage generator 200. The voltages Von and Voff are supplied from the circuit to open the path to transfer the voltage values of the pixels on the LCD panel 500 to the pixels.

The liquid crystal display panel 500 is formed in m data lines, n gate lines arranged orthogonal to the data lines, and a predetermined region lattice arranged between the data lines and the gate lines, one end of which is disposed on the gate line. A pixel electrode connected to the other end and connected to the data line, and the gate voltages G1, G2,..., Gn provided from the gate driver 400 are applied to the corresponding pixel from the data driver 300. The corresponding embedded pixel electrode is driven in response to the provided data voltages D1, D2, ..., Dm.

In more detail, in the liquid crystal display panel 500, a region surrounded by the gate line and the data line constitutes a pixel, and each pixel includes a thin film transistor (TFT) having a gate electrode and a source electrode connected to the gate line and the data line, respectively. The liquid crystal capacitor Clc and the storage capacitor Cst are connected to the drain electrode of the thin film transistor.

Here, one end of the liquid crystal capacitor Clc is connected to the drain electrode of the thin film transistor TFT, and the other end thereof is connected to the common electrode voltage Vcom.

In addition, one end of the storage capacitor Cst is connected to the drain electrode of the thin film transistor TFT, and the other end has an independent wiring structure connected to the other end of the storage capacitor Cst formed in the adjacent pixel. Of course, the number of data lines corresponding to the number of pixels of the liquid crystal display panel is preferably a multiple of two.

Next, the operation of the liquid crystal display panel according to the above features of the present invention will be described in detail.

)는 외부에서 전압을 인가해주지 않더라도 모든 저장 캐패시터의 용량이 동일하기 때문에 하기하는 수학식 1, 2와 같이 결정된다.The potentials of the first and second independent wirings connecting the first, second, and third and fourth storage capacitors Cst arranged in the horizontal direction (

) Is determined as in Equations 1 and 2 below because all storage capacitors have the same capacity even if no voltage is applied from the outside.

와 같이, 제2 픽셀 전압(Vp2)의 저장 캐패시터에 저장되는 제2 전하량(Q₂)은

와 같이 충전되어 저장 캐패시터(Cst)의 원래 목적인 액정 용량의 보조 용량으로서의 역할을 동일하게 할 수 있다.Therefore, the first charge amount Q ₁ stored in the storage capacitor of the first pixel voltage Vp1 is

As such, the second charge amount Q ₂ stored in the storage capacitor of the second pixel voltage Vp2 is

It can be charged as follows to make the role of the storage capacitor Cst as the auxiliary capacity of the liquid crystal capacitor which is the original purpose.

와 같이, 제4 픽셀 전압(Vp4)의 저장 캐패시터에 저장되는 제4 전하량(Q₄)은

와 같이 충전되어 저장 캐패시터(Cst)의 원래 목적인 액정 용량의 보조 용량으로서의 역할을 동일하게 할 수 있다.In addition, the third charge amount Q ₃ stored in the storage capacitor of the third pixel voltage Vp3 is

As such, the fourth charge amount Q ₄ stored in the storage capacitor of the fourth pixel voltage Vp4 is

It can be charged as follows to make the role of the storage capacitor Cst as the auxiliary capacity of the liquid crystal capacitor which is the original purpose.

In the storage capacitor design of the liquid crystal display panel structure, the discharge direction of both ends of the storage capacitor is always reversed during the turn-off time of the thin film transistor (TFT). The rise or fall of the potential gives the level shift effect of the potential of the opposite side, and can be set to 1/2 level as compared with the rise or fall of the pixel potential in the conventional liquid crystal display panel structure.

However, because the equivalent storage capacitance is 1/2, the RC time constant is reduced, resulting in the same discharge characteristics as a whole.

FIG. 6 is a diagram illustrating line damage that may occur in a liquid crystal display panel according to an exemplary embodiment of the present invention.

Referring to FIG. 6, the storage electrode line connected to the switching element of the k-th gate line and the k + 1-th gate line are adjacent to each other. In this case, even if the line damage occurs, the short does not occur over the entire line. Since line damage occurs, recovery is possible.                     

7 is a diagram for describing line damage occurring on a liquid crystal display panel according to another exemplary embodiment of the present invention.

Referring to FIG. 7, even if line damage occurs between the storage electrode line connected to the switching element of the k-th gate line and the k-th gate line, short is not generated over the entire line, and line damage occurs only in the corresponding pixel portion. Is possible.

As described above, according to an embodiment of the present invention and another embodiment, by connecting the even-numbered storage capacitor and the odd-numbered storage capacitor in the same independent wiring, the number of the liquid crystal charging polarity connected to the storage capacitor is always the same By allowing the storage capacitors to form a self-compensating structure, even if a pixel defect occurs due to a short circuit of the storage capacitor wiring and the gate line, it can be detected more easily, and correction of the detected line damage can be performed more easily. have.

For example, even if the storage capacitor wiring of the previous stage and the gate line of the current stage are shorted to each other, the damaged pixel can be detected more easily, and the detected pixel can be more easily corrected.

Further, even if the storage capacitor wiring of the current stage and the gate line of the current stage are shorted to each other, the damaged pixels can be detected more easily, and the detected pixels can be more easily corrected.

In the above-described embodiments of the present invention and other embodiments, as shown in FIGS. 5 to 7, independent storage wirings, that is, storage capacitors existing in odd-numbered pixels and storage capacitors existing in even-numbered pixels, that is, two storage capacitors are independently wired. As an example, the connection to the structure has been described, but four storage capacitors respectively present in the first to fourth pixels may be connected to each other in an independent wiring structure, or six storage capacitors respectively present in the first to sixth pixels may be connected to each other. You can also connect

Next, an example in which four storage capacitors are connected in an independent wiring structure will be briefly described with reference to the accompanying drawings.

FIG. 8 is a diagram for describing a liquid crystal display panel having a storage capacitor having an independent wiring structure according to still another embodiment of the present invention.

Referring to FIG. 8, the first to fourth storage capacitors are connected to the same first independent line, and the fifth to sixth storage capacitors are connected to the same second independent line. Of course, the number of data lines corresponding to the number of pixels of the liquid crystal display panel is preferably a multiple of four.

When driving the liquid crystal display, adjacent data lines receive data voltages having different polarities, and the number of liquid crystal charging polarities charged in storage capacitors connected by independent wiring is always the same. Therefore, the TFT LCD having the storage capacitor according to the embodiment of the present invention has the same storage capacitance characteristic as before.

As described above, when the wiring lines and the gate lines of adjacent storage capacitors are shorted to each other at an arbitrary position, the amount of capacitance applied to the gate lines is small, so that the adverse effect on the display is small and is restored. You may not.                     

When the storage capacitor wiring and the gate line which drive the following pixels are shorted with each other, only a specific pixel is affected, thereby minimizing the occurrence of pixel damage, and thus, the laser restoration process can be easily performed by finding a position to restore.

Further, another embodiment of the present invention is to connect 2N storage capacitor electrodes of pixels having different liquid crystal charging polarities by independent wiring. That is, the number of positive charged pixels connected to the storage capacitor independent wiring and the number of negative charged pixels are the same so that the storage capacitors become the auxiliary capacitances between each other and affect only a specific position when a line short occurs. This can be confined to facilitate the search for a restore location.

As described above, in the related art, all the storage capacitor electrode lines are bundled together to apply a separate external voltage. However, according to the present invention, 2N (N is a positive integer) of the storage capacitor electrode lines adjacent to each other in the horizontal direction are connected to each other. The yield of the liquid crystal display panel can be increased.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

As described above, by independently configuring the connection wiring between the storage capacitors arranged in the horizontal direction according to the present invention, even if a line damage occurs between the storage capacitor line and the gate line in the manufacturing process of the liquid crystal display panel, it can be more easily detected. And correction of the detected line damage can be performed more easily.

Claims (18)

A plurality of data lines for transmitting image signals; A plurality of gate lines transmitting scan signals; A switching element connected to the gate line through a first stage and connected to a data line through a second stage; And A liquid crystal capacitor connected to the third end of the switching element, and a storage capacitor connected to the third end of the switching element through one end, And the other end of the storage capacitor is paired with 2N (where N is an integer) and the other end of the other storage capacitor adjacent to each other and are connected by independent wiring. delete 2. The liquid crystal display panel of claim 1, wherein the number of data lines is a multiple of 2N (where N is an integer). The liquid crystal display panel of claim 1, wherein a positive charge amount and a negative charge amount of the liquid crystal capacitor connected to the storage capacitor are the same. The liquid crystal display panel of claim 1, wherein a voltage is not applied from an external source to independent wirings connecting the other ends of the storage capacitors. The liquid crystal display panel of claim 1, wherein the independent wiring and the gate line connecting the other ends of the storage capacitor are positioned on the same plane. The liquid crystal display panel of claim 6, wherein the independent wiring and the gate line connecting the other ends of the storage capacitor are formed of the same metal material. The liquid crystal display panel of claim 1, wherein a charging polarity of a liquid crystal capacitor connected to the connected storage capacitor is different from a charging polarity of a capacitance of an adjacent liquid crystal capacitor. The liquid crystal display panel of claim 1, wherein adjacent data lines of the data lines are column inverted upon receiving an image signal having a different polarity. A timing controller configured to output a first control signal for outputting a scan signal and a second control signal for outputting an image signal; A scan driver configured to output a scan signal based on the first control signal; An image driver for outputting an image signal based on the second control signal; And A plurality of data lines for transmitting the image signal, a plurality of gate lines for transmitting the scan signal, a switching element connected to the gate line through a first stage and a data line through a second stage, and A liquid crystal display panel having a liquid crystal capacitor connected to a third end of the switching element, and a storage capacitor connected to the third end of the switching element through one end thereof; And the other end of the storage capacitor is paired with 2N (where N is an integer) and the other end of another storage capacitor adjacent to each other and connected to each other by independent wiring. delete The liquid crystal display device according to claim 10, wherein the number of data lines is a multiple of 2N (where N is an integer). The liquid crystal display of claim 10, wherein a positive charge amount and a negative charge amount of the liquid crystal capacitor connected to the storage capacitor are the same. The liquid crystal display device of claim 10, wherein a voltage is not applied from the outside to the independent wirings connecting the other ends of the storage capacitors. The liquid crystal display of claim 10, wherein the independent wiring and the gate line connecting the other ends of the storage capacitor are located on the same plane. The liquid crystal display of claim 15, wherein the independent wiring and the gate line connecting the other ends of the storage capacitor are formed of the same metal material. The liquid crystal display of claim 10, wherein the charging polarity of the liquid crystal capacitor connected to the connected storage capacitor is different from the charging polarity of the capacitance of the adjacent liquid crystal capacitor. The liquid crystal display of claim 10, wherein adjacent data lines of the data lines are column inverted upon receiving an image signal having a different polarity.

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