WO2015014065A1

WO2015014065A1 - Method for detecting short circuit of signal line and repair line

Info

Publication number: WO2015014065A1
Application number: PCT/CN2013/088996
Authority: WO
Inventors: 汤展峰; 刘俊豪; 张明亮
Original assignee: 合肥京东方光电科技有限公司; 京东方科技集团股份有限公司
Priority date: 2013-07-31
Filing date: 2013-12-10
Publication date: 2015-02-05
Also published as: CN103399422A; CN103399422B

Abstract

A method for detecting short circuit of a signal line and a repair line (9') comprises the steps of: when pixels are driven to be displayed in a liquid crystal cell detection phase, applying first detection voltage to a signal line, and applying second detection voltage unequal to the first detection voltage to a repair line (9') at the same time; detecting the display conditions of the pixels; and if preset abnormal display happens to the pixels driven by the signal line, detecting a situation that the signal line and the repair line (9') are in a short circuit. When the first detection voltage is applied to the signal line, the second detection voltage is applied to the repair line (9') at the same time, as a result, if the signal line and the repair line (9') are in the short circuit, the second detection voltage is used for increasing the voltage difference between the signal line in short circuit with the repair line (9') and other signal lines, therefore, the difference of final display is amplified, and which signal line is in short circuit with the repair line (9') can be detected more easily.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of detecting a short circuit between a signal line and a repair line. Background technique

In the manufacture of thin film transistor liquid crystal displays (TFT-LCDs), small size products typically use a Shorting Bar test during the Cell Test process. As shown in FIG. 1, a common electrode line 4 is formed on the display panel, a shorting bar corresponding to the driving red sub-pixel data line 5, a shorting bar 2 corresponding to the driving green sub-pixel data line 6, and a driving blue sub-pixel data line 7 are provided. Corresponding shorting bar 3. Three shorting bars 1, 2, and 3 are connected to the corresponding data lines 5, 6, and 7 through vias 8, respectively, for applying detection voltages to data lines 5, 6, and 7.

A repair line 9 is also formed on the display panel. If one of the data lines is short-circuited with the repair line 9, as shown in FIG. 1, a certain data line 6 and the repair line 9 are short-circuited at the intersection 10, and the detection of the data line 6 is performed. The voltage is pulled low (the voltage of the data line is positive, and the repair line voltage is zero, that is, no voltage). However, since the repair line 9 itself has no voltage, and the data line 6 is connected to other data lines 6 (the data lines driving the same color sub-pixels are connected together), the repair line 9 can only pull the voltage of these data lines 6 to a minimum. In part, the difference between the data line 6 short-circuited to the repair line 9 and the un-short-circuited data line 6 is small, that is, the voltage of the pixel electrode driven by the short-circuited data line 6 and the pixel electrode driven by the other data line 6. The gap is small, the difference in liquid crystal deflection is not obvious, and the difference in display color is not obvious, so this short-circuit defect is not easy to detect. In the module phase, the full contact detection mode is adopted. The data line 6 is not connected to other data lines 6 (disconnected along the broken line in the figure), and the repair line 9 can pull down the data line 6 When the voltage and voltage are small, the degree of liquid crystal deflection is different from that of the normal area, and the detection phenomenon is a bright line. However, after the detection is made, if the problem is serious, the entire panel may be scrapped. If it is not serious, the repair process will be additionally added. Therefore, there is a need for a method capable of detecting a situation in which a data line and a repair line are short-circuited during a Cell Test phase. Summary of the invention

In order to solve the above technical problem, the present invention provides a method for detecting a short circuit of a signal line and a repair line, including:

Applying a first detection voltage to the signal line while a pixel display is being driven, and applying a second detection voltage that is not equal to the first detection voltage to the repair line;

The display condition of the pixel is detected, and if a predetermined display abnormality occurs in the pixel driven by the signal line, it is detected that the signal line and the repair line are short-circuited.

Wherein the signal line is connected to the shorting bar, and the first detection voltage is applied to the signal line through the shorting bar.

Wherein the repair line is connected to the common electrode line, and the voltage of the common electrode line is applied to the repair line as the second detection voltage.

The signal line includes: a gate line or a data line.

The data line is connected to a data line short-circuit strip; or the data line driving the same color sub-pixel is connected to the same data line short-circuit strip, and the data lines driving the different color sub-pixels are connected to different data line short-circuit strips. A first detection voltage is applied to the different data lines by different data line shorting bars.

The predetermined display abnormality includes: the display of the pixel driven by the data line short-circuited with the repair line has the largest difference from the normal monochrome picture, and the two sides of the pixel driven by the data line short-circuited with the repair line Extending, the closer the display color is to the normal monochrome picture, the normal monochrome picture is a monochrome picture that should be displayed when the data line is not short-circuited with the repair line.

The gate line is connected to the gate line shorting bar, and the first detection voltage is applied to the gate line through the gate line shorting bar.

The first detection voltage is smaller than an opening voltage of the gate line driven thin film transistor, the second detection voltage is not less than an opening voltage of the gate line driven thin film transistor; or the first detection voltage is not less than the The turn-on voltage of the gate line driven thin film transistor, the second detection voltage is small The turn-on voltage of the thin film transistor driven by the gate line.

The predetermined display abnormality includes: a pixel driven by a gate line short-circuited with the repair line and a pixel within a certain width of both sides thereof display a monochrome picture different in color from a normal monochrome picture, the normal monochrome The picture is a monochrome picture that should be displayed when the gate line is not short-circuited with the repair line.

The present invention applies a second detection voltage to the repair line while applying a first detection voltage to the signal line, and if the signal line and the repair line are short-circuited, the signal line and the other signal line are short-circuited by the second detection voltage. The difference is increased, thereby amplifying the degree of difference in the final display, thereby making it easier to detect which signal line is short-circuited with the repair line. BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments will be briefly described below. It is obvious that the drawings in the following description relate only to some embodiments of the present invention, rather than Limitations of the invention.

1 is a schematic view of short circuit strip detection in the prior art;

2 is a flow chart of a method for detecting a short circuit condition of a data line and a repair line according to an embodiment of the present invention;

Figure 3 is a schematic illustration of the detection using the method of the present invention. detailed description

The technical solutions of the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings. It is apparent that the described embodiments are part of the embodiments of the invention, rather than all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the described embodiments of the present invention without departing from the scope of the invention are within the scope of the invention.

Unless otherwise defined, technical terms or scientific terms used herein shall be of ordinary meaning as understood by those of ordinary skill in the art to which the invention pertains. Patent application specification and right of the present invention The terms "first", "second" and similar terms used in the claims do not denote any order, quantity or importance, but are merely used to distinguish different components. Similarly, the words "a" or "an" do not denote a quantity limitation, but rather mean that there is at least one. The words "including" or "comprising", etc., are intended to mean that the elements or objects preceding "including" or "comprising" are intended to encompass the elements or Component or object. "Connected" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Upper", "Bottom", "Left", "Right", etc. are only used to indicate the relative positional relationship. When the absolute position of the object to be described is changed, the relative positional relationship may also change accordingly.

The specific embodiments of the present invention are further described in detail below with reference to the drawings and embodiments. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

As shown in FIG. 2, the method for detecting a short circuit between a signal line and a repair line according to an embodiment of the present invention includes:

Step S210, when driving the pixel display, applying a first detection voltage to the signal line, and simultaneously applying a second detection voltage that is not equal to the first detection voltage to the repair line;

Step S220, detecting the display condition of the pixel, if the pixel corresponding to the signal line driving does not meet the display abnormality of the predetermined screen, detecting that the signal line and the repair line are short-circuited.

In the display field, when detecting a liquid crystal cell, the signal line usually includes a gate line and a data line, and the data line is taken as an example for detailed description below.

In step S210, a first detection voltage may be applied to the data line by means of an external signal line, and a second detection voltage is also applied to the repair line through a different external signal line.

In this embodiment, whether the data line and the repair line are short-circuited can be detected based on the detection structure of the Shorting Bar detection mode. As shown in FIG. 3, specifically, the data lines 5', 6', and Ύ are respectively connected to corresponding data line shorting bars, 2' and 3'. The repair line 9' is connected to a different signal source than the shorting bar, preferably, in order not to additionally increase the signal source, the repair line 9' is connected to the common electrode line 4' via the wire 11' (the display device usually has a common electrode line) And data lines The applied voltage is different). Applying a first detection voltage of a different voltage value to the data lines 5', 6 ¹ and 7' through the data line shorting bars, 2' and 3', respectively, while applying the voltage of the common electrode line as a second detection voltage to the Said repair line 9'. It is also possible to apply the first detection voltage to the data lines 5', 6' and 7' by the data line shorting bars, T and Ύ, while applying the voltage of the common electrode line as the second detection voltage to the repair line 9' .

In step S220, the detection mode can control the deflection of the liquid crystal by the voltage difference between the data line shorting strip, 2' and 3' and the common electrode line 4' to realize various predetermined test color pictures (the monochrome picture is usually displayed during the test) If a bright line or a dark line is abnormal in the screen, the corresponding problem that the data line and the repair line are short-circuited is detected.

Taking the second detection voltage less than the first detection voltage as an example, as shown in FIG. 3, one of the data lines 6' is short-circuited with the repair line 9' (eg, the data line 6' and the repair line 9' are at the intersection 10' A short circuit occurs and the voltage of all data lines 6' is pulled low. When the common electrode line 4' is not connected with respect to the repair line 9', the voltage of the data line 6' short-circuited with the repair line 9' is pulled lower. The further the other data lines 6 from the shorted data line 6' are pulled down, the smaller the extent. The voltage of the shorted data line 6' is pulled to a minimum such that the voltage difference between the common electrode and the pixel electrode driven by the shorted data line 6' is not equal to the voltage between the common electrode and the pixel electrode driven by the other data line 6'. Poor, and the voltage difference between the common electrode and the pixel electrode driven by the shorted data line 6' is significantly smaller than the voltage difference between the common electrode and the pixel electrode driven by the other data line 6' (especially relative to the common electrode and the off-short data) Line 6' is the voltage difference between the pixel electrodes driven by the farther data line 6'). The difference in voltage difference causes the degree of liquid crystal deflection to be significantly different from the normal area. The detection phenomenon is that the pixel display driven by the shorted data line 6' has the largest difference from the normal monochrome picture, and the closer to the two sides of the pixel, the closer the color is to the normal single. The color picture, so that it is easier to determine which data line 6' is short-circuited with the repair line 9', depending on where the picture difference is greatest. The normal monochrome picture is a monochrome picture that should be displayed when the data line 6' is not short-circuited with the repair line 9'. If the second detection voltage is greater than the first detection voltage, the shorted data line 6' and the other data line 6' are pulled high, and the detection principle and the second detection voltage are similar to the first detection voltage, and are not described herein again. In the detection phase, the monochrome mode is usually used for detection, that is, the entire screen displays only one color. Using different data line shorting bars, and y applying different detection voltages of different sizes, the data line driven red, green and blue pixels can be combined into a plurality of different single colors. When the first detection voltage is applied with different data line shorting bars and y minutes, the screen displays red, green and blue monochrome pictures, which makes the detection more accurate.

Of course, only one data line shorting bar can be set, and the first detection voltage is applied to all the data lines through the data line shorting bar, which is especially suitable for some monochrome display devices.

For short circuit of the gate line and the repair line, the gate line shorting bar applies a first detection voltage to the gate line that is smaller than the turn-on voltage of the thin film transistor TFT driven by the gate line, that is, the gate line cannot open the TFT, and the data line cannot charge the corresponding pixel electrode. The display screen at this time is a normal monochrome screen (that is, the display screen when the pixel electrode is not powered. At this time, the liquid crystal does not deflect. If it is a normally black mode, the backlight cannot pass through, and usually displays black, if it is always white. Mode, the backlight can pass through, showing the same white picture as the backlight). The common electrode line shorting bar applies a thin film transistor that is not smaller than the gate line driving for the repair line

The second detection voltage of the turn-on voltage of the TFT. If a certain gate line is short-circuited with the repair line, it is equivalent to applying a voltage of the common electrode line to the gate line, the TFT driven by the gate line is turned on, and the data line is charged for a row of pixels opened by the gate line, the row of pixels The liquid crystal is deflected. Since the gate lines are all connected to the shorting bars, the voltage of the gate lines is pulled high, and the voltage of the gate lines closer to the shorting gate lines is higher than the voltage of the gate lines farther from the shorting gate lines. May be larger than the open voltage of the TFT. Therefore, the gate line driving TFT closer to the short-circuit gate line is in an open state, and the data line charges the plurality of rows of pixels opened by the gate lines, and the liquid crystal of the plurality of rows of pixels is deflected to display a screen different from the normal monochrome screen. (Normally, a short-width gate line driving pixel and a pixel within a certain width on both sides thereof display a monochrome picture of a different color from a normal monochrome picture), thereby detecting which gate line is short-circuited with the repair line. The normal monochrome picture is a monochrome picture that should be displayed when the gate line is not short-circuited with the repair line. There are no areas of different colors.

Or the gate line shorting bar applies a first detection voltage to the gate line that is not less than the turn-on voltage of the gate line-driven thin film transistor TFT, that is, the gate driving signal can turn on the TFT, and the common electrode line short-circuit strip A second detection voltage that is smaller than the turn-on voltage of the gate line-driven thin film transistor TFT is applied to the repair line. Under normal circumstances, each gate line can open the TFT of the corresponding row, so a normal picture of a certain color is displayed. If a certain gate line is short-circuited with the repair line, the voltage of the gate line is pulled down to the second detection voltage. Since the gate lines are connected to the shorting bars, the voltage of the gate lines is pulled down, and the voltage of the gate lines closer to the shorting gate lines is lower than the voltage of the gate lines farther from the shorting gate lines. May be smaller than the TFT's turn-on voltage. Therefore, the TFTs driven by the gate lines and the adjacent gate lines cannot be turned on, and the data lines cannot charge the pixels corresponding to the gate lines, and the liquid crystals of the pixels of the line are not deflected to display a picture different from the normal picture (if the black mode is normal) The backlight is not transparent. Usually, the short-circuited gate line drives the pixels and pixels within a certain width of the two sides to display a black picture. If the white-light mode is used, the backlight can pass through, usually within a certain width of the short-circuited gate line driving pixels and both sides thereof. The pixels display the same white picture as the backlight, thereby detecting which gate line is shorted to the repair line.

After the detection, if there is no abnormality in the liquid crystal cell, you can enter the Module stage. Before entering the Module stage, cut or turn off the line connecting the signal line and the short-circuit bar, and also connect the repair line and the common electrode line short-circuit bar. The line is cut or turned off.

The present invention applies a second detection voltage to the repair line while applying a first detection voltage to the signal line, and if the signal line and the repair line are short-circuited, thereby further increasing the signal line between the repair line and the other signal line. The voltage difference makes it easy to detect which signal line is shorted to the repair line through the display screen.

The above embodiments are merely illustrative of the present invention and are not to be construed as limiting the scope of the invention, and various modifications and changes can be made without departing from the spirit and scope of the invention. Equivalent technical solutions are also within the scope of the invention, and the scope of the invention is defined by the claims.

Claims

claims

1. A method for detecting short circuits in signal lines and repair lines, including:

When driving the pixel display during the liquid crystal cell detection stage, a first detection voltage is applied to the signal line, and a second detection voltage that is not equal to the first detection voltage is applied to the repair line;

The display condition of the pixel is detected. If a predetermined display abnormality occurs in the pixel driven by the signal line, a short circuit between the signal line and the repair line is detected.

2. The method of claim 1, wherein the signal line is connected to a short-circuit bar, and the first detection voltage is applied to the signal line through the short-circuit bar.

3. The method of claim 1 or 2, wherein the repair line is connected to a common electrode line, and the voltage of the common electrode line is applied to the repair line as the second detection voltage.

4. The method according to any one of claims 1 to 3, wherein the signal lines include: gate lines or data lines.

5. The method of claim 4, wherein the data line is connected to a data line short-circuit bar; or data lines driving sub-pixels of the same color are connected to the same data line short-circuit bar to drive data of sub-pixels of different colors. Lines are connected to different data line short-circuit bars, and the first detection voltage is applied to the different data lines through the different data line short-circuit bars.

6. The method of claim 5, wherein the predetermined display abnormality includes: the display of the pixel driven by the data line short-circuited to the repair line is the largest difference from the normal monochrome picture, and the difference between the display and the repair line is the largest. The pixels driven by the short-circuited data line extend on both sides, and the display color is closer to the normal monochrome picture. The normal monochrome picture is the monochrome picture that should be displayed when the data line is not short-circuited with the repair line.

7. The method of claim 4, wherein the gate line is connected to a gate line short-circuit bar, and the first detection voltage is applied to the gate line through the gate line short-circuit bar;

The first detection voltage is less than the turn-on voltage of the gate line-driven thin film transistor, and the second detection voltage is not less than the turn-on voltage of the gate line-driven thin film transistor; or the first detection voltage is not less than the The second detection voltage is less than the turn-on voltage of the gate line driven thin film transistor.

8. The method of claim 7, wherein the predetermined display anomaly includes: the pixels driven by the gate line short-circuited with the repair line and the pixels within a certain width on both sides display differently from the normal monochrome picture. The normal monochrome picture is the monochrome picture that should be displayed when the gate line is not short-circuited with the repair line.