KR20040061673A - Apparatus for inspecting liquid crystal display - Google Patents

Abstract

PURPOSE: An inspection device of an LCD device is provided to configure a TG(Transmission Gate) signal applying pad for applying a TG driving signal on the same TFT substrate as an OS(Open Short) pad, and to connect a channel terminal with data lines when the data lines are inspected as being inferior, thereby transmitting a test signal up to the OS pad. CONSTITUTION: A TFT substrate(200) forms a pixel array. A PCB supplies an image signal to the TFT substrate(200). Plural driving ICs(210) receive the image signal from the PCB. A flexible cable film electrically connects the PCB with the driving ICs(210). The TFT substrate(200) is configured by a COG(Chip On Glass) method for directly configuring the driving ICs(210) on the TFT substrate(200). Plural gate lines are arrayed on the TFT substrate(200) in width direction. Plural data lines(DL) are arrayed along a longitudinal direction of the TFT substrate(200) to cross the gate lines.

Description

Inspection device for liquid crystal display device {APPARATUS FOR INSPECTING LIQUID CRYSTAL DISPLAY}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection apparatus for a liquid crystal display device, and more particularly, to an inspection apparatus for a liquid crystal display device for efficiently inspecting short and open data lines.

In general, a liquid crystal display device includes a liquid crystal display panel composed of a thin film transistor (hereinafter referred to as TFT) substrate, a color filter substrate facing the TFT substrate, and a liquid crystal injected between the two substrates. It is a device for displaying information by using optical modulation by a change in optical characteristics of a liquid crystal.

A plurality of gate lines and a plurality of data lines cross each other on the TFT substrate, and thin film transistors and pixel electrodes, which are switching elements, are formed in each of the crossed regions.

The data line receives a gray voltage selected by the source driving driver IC and delivers the gray voltage to the liquid crystal. The gate line opens or closes the thin film transistor, which is a switching element, according to an ON / OFF signal output from the gate driving driver IC.

It is necessary to check whether the gate line or data line of the completed liquid crystal display panel is normally driven before the driving drive IC is formed on the liquid crystal display panel.

That is, a defect occurs in that the gate line or the data line generated by the metal process during the manufacturing of the liquid crystal display panel is opened due to a step of the lower layer or a defective element such as a PC (Particle) during exposure. As such, an inspection performed to inspect a defect occurring in a gate line or a data line is referred to as an OS test (Open Short test).

In general, OS testing involves the connection of a TCP to the Shorting Bar, which connects the gate line or data line to the drive drive IC after the metal process that creates the gate line and data line, and before the edge grinding process. Is performed using

1 is a view showing a liquid crystal display according to the prior art.

Referring to FIG. 1, a liquid crystal display according to the related art includes a TFT substrate 100 having a pixel array, a driving printed circuit board (not shown) for providing a driving signal to the TFT substrate 100, and a TFT substrate 100. ) And a tape carrier package (hereinafter referred to as TCP) 110 for electrically connecting the driving printed circuit board.

A plurality of data lines 120 extending in the row direction are formed in the TFT substrate 100, and a plurality of gate lines (not shown) are formed in the column direction. In addition, the TCP 110 is configured in an edge region of the TFT substrate 100, and a data driving drive IC 130 for driving the data line 120 is configured on the upper surface of the TCP 110. 110, a data pad (not shown) extending from a first end of the plurality of data lines 120 and having a width wider than that of the data lines 120 is formed.

Meanwhile, the TFT substrate 100 extending from the second ends of the plurality of data lines 120 and having a width wider than that of the data lines 120 is opposed to an area where the TCP 110 is configured. Is formed in the region.

The TCP 110 is connected to a shorting bar 150 for performing visual inspection, and the shorting bar 150 has a data signal applying pad configured at one side of a lower region of the glass 160. It is connected to the shorting line (Shorting Line) 180 for applying a signal from the 170 is configured. Here, one or two data signal application pads 170 are formed on the glass 160 including the plurality of TFT substrates 100.

The OS test operation of the liquid crystal display according to the related art configured as described above is as follows.

When the test signal for the OS test is applied to the data signal applying pad 170, the test signal is applied to the shorting bar 150 through the shorting line 180. The test signal applied to the shorting bar 150 is transmitted to the TCP 110, and the TCP 110 outputs a test signal input through the shorting bar 150 to the plurality of data lines DL. The test signal is applied to the OS pad 140 configured at the second end of the data line 120 through the data line 120.

A probe for measuring a predetermined resistance is connected to the OS pad 140, and whether the data line 120 is short or open is determined based on the resistance value detected by the OS pad 140.

That is, if the resistance value detected by the OS pad 140 is greater than the reference resistance value, it is determined that the data line 120 is open. If the detected resistance value is smaller than the reference resistance value, the data line ( 120, it is determined that the short (Short).

As described above, the OS test is possible only when TCP is formed at the edge portion of the TFT substrate and TCP formed at the edge portion is connected to the shorting bar.

Therefore, in the COG mounting type TFT substrate in which the drive drive IC is formed inside the TFT substrate, the wiring defect of the data line cannot be inspected by the above OS test.

In addition, a liquid crystal display device having more data lines than channel terminals and including a switch for selectively connecting the data lines to a drive drive IC is called a liquid crystal display device of a transmission gate (TG) driving method. As described above, the TG driving type liquid crystal display device must first turn on a switch for connecting the data line to the driving drive IC in order to inspect the defect of the data line formed on the TFT substrate.

Here, the load on the switch for connecting the data line to the driving drive IC is very large, and a switch driving signal (TG signal) must be applied to each TFT substrate.

However, in the conventional OS test, since the test signal is applied to the glass composed of a plurality of TFT substrates, the test signal is not properly applied to the switch, and accordingly, the data line is not connected to the driving drive IC. Some problems cannot be inspected.

Accordingly, an object of the present invention is to provide a test apparatus for a liquid crystal display device for performing an OS test of a liquid crystal display device having a chip on glass (COG) mounting method. Is in.

In addition, another object of the present invention is to provide an inspection apparatus for a liquid crystal display device for performing an OS test of the TG driving type liquid crystal display device.

1 is a view showing a liquid crystal display according to the prior art.

2 is a diagram illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

3 is a detailed view of an OS pad unit.

4 is a diagram illustrating a liquid crystal display according to an exemplary embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

200: TFT substrate 210: drive drive IC

220: glass 230: shorting line

240: data signal applying pad 250: OS pad portion

260: V / I line

An inspection apparatus for achieving the above object is configured in the form of surrounding the TFT substrate in the periphery of the glass substrate formed with a plurality of TFT substrate, the test signal line for applying a test signal to the data line; A pixel failure detection line connected to the first end of the data line and configured on the TFT substrate, the both ends extending to be connected to the test signal line; A test signal applying pad configured on the glass substrate to apply a test signal to the test signal line; And a test signal detection pad formed by extending a second end of the data line and receiving a test signal from the pixel failure detection line through the data line.

According to another aspect of the present invention, a test apparatus for a liquid crystal display device includes a test signal line configured to surround a TFT substrate on a slope of a peripheral portion of a glass substrate on which a plurality of TFT substrates are formed, and to apply a test signal to a data line; A pixel failure detection line connected to the first end of the data line and configured on the TFT substrate, the both ends extending to be connected to the test signal line; A test signal applying pad configured on the glass substrate to apply a test signal to the test signal line; Data line connection signal generating pads respectively provided on the plurality of TFT substrates and outputting control signals for selectively connecting data lines to channels; A data line connection signal line configured to be parallel to the data line and outputting a control signal from the data line connection signal generating pad to the data line selection unit; And a test signal detection pad formed by extending a second end of the data line and receiving a test signal from a pixel failure detection line through the data line.

Hereinafter, an OS test apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a view showing a liquid crystal display device according to an embodiment of the present invention, Figure 3 is a detailed view of the OS pad unit.

Referring to FIG. 2, a liquid crystal display according to an exemplary embodiment of the present invention includes a TFT substrate 200 having a pixel array, a printed circuit board (not shown) for providing an image signal to the TFT substrate 200, and A plurality of drive driver IC 210 for receiving an image signal from a printed circuit board and a flexible cable film (not shown) for electrically connecting the printed circuit board and the drive drive IC 210.

Here, the TFT substrate 200 is a substrate of a liquid crystal display panel configured by a chip on glass mounting method in which a plurality of drive drive ICs 210 are directly configured on the TFT substrate 200. A plurality of gate lines (not shown) are arranged in a line along the width direction on the 200, and a plurality of data lines DL along the length direction of the TFT substrate 200 to cross the gate lines. Are arranged in line.

The COG mounting method is a method in which a driving drive IC is mounted on a liquid crystal display panel and a liquid crystal display panel and a printed circuit board are connected by using a connector such as a flexible printed circuit board.

The TFT substrate 200 is formed in plural in the center of the glass 220, and a shorting line 230 is formed on the periphery of the glass 220 so as to surround the plurality of TFT substrates 220. In addition, a data signal application pad 240 for applying a test signal for an OS (Open Short) test of the TFT substrate 200 to the shorting line 230 is formed in one region of the lower surface of the glass 220.

A data pad (not shown) is formed on the rear surface of the driving drive IC 210 and extends from the first ends of the plurality of data lines DL and has a width wider than that of the data lines DL. In addition, a TFT extending from a second end of the plurality of data lines DL and having an OS pad portion 250 having a width wider than that of the data lines DL, is opposed to an area in which the driving drive IC 210 is formed. It is formed in the region of the substrate 200. In this case, as illustrated in FIG. 3, the OS pad unit 250 includes a plurality of OS pads 300 extending from the second end of the data line DL and having a wider width than the data line DL.

In addition, a V / I (Visual / Inspection) line 260 connected to data pads of a plurality of data lines DL is formed in a region of the TFT substrate 200 in which the driving drive IC 210 is formed. Here, the V / I line 260 is extended to be connected to the shorting line 230 for the OS test. That is, the data line DL is connected to the shorting line 230 through the V / I line 260 connected to the data pad.

In this case, the V / I line 260 is a line for visual inspection performed before the polarizer is attached to the TFT substrate 200. The V / I line 260 applies a data signal to the V / I line 260 to perform pixel unit. It is to check the defect of the.

In the above configuration, the shorting line 230 is removed in an edge grinding process after an OS test for wiring inspection.

The OS test operation of the TFT substrate according to the exemplary embodiment of the present invention configured as described above is as follows.

When the test signal for the OS test is applied to the data signal applying pad 240, the test signal is applied to the V / I line 260 through the shorting line 230. The test signal applied to the V / I line 260 is output to a plurality of data lines DL through a data pad formed on the back side of the driving drive IC 210, and the data signal DL of the data line DL through the data line DL. The second end portion is extended to the OS pad part 250.

Subsequently, when a probe card for measuring a predetermined resistance is connected to the OS pad part 250, a short or open of the data line DL is performed through a resistance value detected by the OS pad part 250. Determine whether or not.

That is, if the resistance value detected by the OS pad unit 250 is larger than the reference resistance value, it is determined that the data line DL is open. If the detected resistance value is smaller than the reference resistance value, the data line is determined. It is determined that (DL) is short.

4 is a diagram illustrating a liquid crystal display according to another exemplary embodiment of the present invention.

Referring to FIG. 4, a liquid crystal display according to another exemplary embodiment of the present invention may include a TFT substrate 400 having a pixel array, a printed circuit board (not shown) for providing an image signal to the TFT substrate 400, and the like. A plurality of drive driver ICs 410 for receiving image signals from a printed circuit board, a data line selector 420 for selectively connecting data lines to channel terminals CH of the drive drive ICs 410, and the printing A flexible cable film (not shown) for electrically connecting the circuit board and the drive drive IC 410 is provided.

Here, a plurality of TFT substrates 400 are formed at the center of the glass 430, and a shorting line 440 is formed on the slopes of the periphery of the glass 430 to surround the TFT substrate 400. In addition, a data signal application pad 450 for applying a test signal for an OS test of the TFT substrate 400 to the shorting line 440 is formed in one region of the lower surface of the glass 430.

The TFT substrate 400 is a chip on glass (COG) panel in which a plurality of driving drive ICs 410 are directly configured on the TFT substrate 400, and a plurality of gate lines (not shown) on the TFT substrate 400. ) Are arranged in a line along the width direction, and a plurality of data lines DL are arranged in a line along the length direction of the TFT substrate 400 so as to intersect the gate lines.

In addition, the data line selector 420 includes a plurality of transistors (not shown) that are turned on or off according to a signal applied to a gate, and the data line selector 420 of the driving drive IC 410 according to the switching operation of the transistors. The channel terminal CH and a plurality of data lines DL are selectively connected.

One end of the plurality of data lines DL extends and includes an OS pad part 460 including a plurality of OS pads having a width wider than that of the data line DL. It is formed in the region of the opposing TFT substrate 400. Here, the OS pad unit 460 has the same configuration as the embodiment of the present invention.

In addition, a V / I (Visual / Inspection) line 465 connected to the data pads of the plurality of data lines DL is formed in the region of the TFT substrate 400 in which the driving drive IC 410 is formed. Here, the V / I line 465 extends to be connected to the shorting line 440 for the OS test. That is, the data line DL is connected to the shorting line 440 through the V / I line 465 connected to the data pad.

In addition, a TG signal applying pad 470 to which a TG (Transmission Gate) signal for turning on the transistor of the data line selector 420 is input is configured in the same region as the OS pad unit 460 and the TG signal is applied. A TG line 480 for applying the TG signal from the pad 470 to the data line selector 420 is formed on one surface of the periphery of the TFT substrate 400 to be parallel to the data line DL.

Here, the shorting line 440 is removed in the edge grinding process after the OS test is performed.

Referring to the OS test operation of the liquid crystal display according to another embodiment of the present invention having such a configuration as follows.

First, a transistor of the data line selector 420 is turned on to the TG signal applying pad 470 to apply a TG signal for selectively connecting a plurality of channels and data lines. The TG signal applied through the TG signal applying pad 470 is output to the data line selector 420 through the TG signal line 480, and the data line selector 420 is input through the TG signal line 480. A plurality of data lines and a plurality of channel terminals are connected in accordance with the TG signal.

Subsequently, when a test signal for OS test is applied to the data signal application pad 450, the test signal is output to the V / I line 465 through the shorting line 440. The test signal output to the V / I line 465 is output to the data line selector 410 through a plurality of channel terminals CH formed on the back side of the drive drive IC 410 and to the data line selector 410. The input test signal is output to the data line DL selectively connected to the channel terminal CH. The test signal input to the data line DL is applied to the OS pad part 460 having an extended end.

Subsequently, as a probe card for measuring a predetermined resistance is connected to the OS pad unit 460, a short or open of the data line DL is performed through a resistance value detected by the OS pad unit 460. Determine whether or not.

That is, if the resistance value detected by the OS pad unit 460 is larger than the reference resistance value, it is determined that the data line DL is open. If the detected resistance value is smaller than the reference resistance value, the data line is determined. It is determined that (DL) is short.

As described above, the inspection apparatus for the liquid crystal display panel according to the present invention extends both ends of the V / I line to the shorting line in the TFT substrate in which the drive drive IC is configured inside the panel and is not connected to the shorting line.

Therefore, the present invention has the effect that a data wiring test, that is, an OS test, which was possible only in a TFT substrate in which TCP is configured in an edge region of the TFT substrate, can be performed even in a COG TFT substrate in which a drive driver IC is configured inside the TFT substrate. have.

In addition, the inspection apparatus of the liquid crystal display panel according to the present invention includes a TG signal applying pad for applying a TG driving signal for selectively connecting the channel terminal and the data line of the driving drive IC to the TFT substrate in the same line as the OS pad. Configured on the TFT substrate, the test signal can be transmitted to the OS pad as the channel terminal and the data line are connected during the data wiring defect inspection.

Therefore, the present invention also has the effect that data wiring defect inspection can be performed even on a TG driving TFT substrate driven by a TFT substrate.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. I can understand that you can.

Claims (4)

A driving drive circuit including a plurality of pixels including a gate line, a data line, a switching element connected to the gate line and the data line, and an electrode connected to the switching element, and a driving drive circuit providing a driving signal to the data line is provided in the TFT substrate. In the inspection apparatus of the liquid crystal display device directly configured, A test signal line configured to surround the TFT substrate at a periphery of a glass substrate having a plurality of the TFT substrates, and to apply a test signal to the data line; A pixel failure detection line connected to a first end of the data line and configured in the TFT substrate region, the both ends of which extend to be connected to the test signal line; A test signal applying pad configured on the glass substrate to apply the test signal to the test signal line; And A test signal detection pad connected to a second end of the data line and receiving the test signal from the pixel failure detection line through the data line; And measuring a resistance value of a test signal applied to the test signal detecting pad to detect a wiring defect of the data line. The inspection apparatus of claim 1, wherein the test signal detection pad has a width wider than that of the data line. The method of claim 1, A data line selector for selectively connecting the data line to a plurality of channels configured in the driving drive circuit; Data line connection signal generation pads respectively configured on the plurality of TFT substrates and outputting control signals for selectively connecting the data lines to the channel; And And a data line connection signal line configured to be parallel to the data line and outputting a control signal from a data line connection signal generating pad to the data line selection unit. A drive drive circuit including a plurality of pixels including a gate line, a data line, a switching element connected to the gate line and the data line, and an electrode connected to the switching element, and a driving drive circuit configured to provide a driving signal to the data line is provided in the panel. An apparatus for inspecting a liquid crystal display device, comprising: a TFT substrate configured directly and having a data line selector for selectively connecting a plurality of channels of the drive drive circuit and the data line; A test signal line configured to surround the TFT substrate on a slope of a plurality of glass substrate peripheral parts formed with the TFT substrate, and to apply a test signal to the data line; The pixel failure detection line connected to a first end of the data line and configured in the TFT substrate region, and extended at both ends, and connected to the test signal line; A test signal applying pad configured on the glass substrate to apply the test signal to the test signal line; Data line connection signal generating pads respectively configured on the plurality of TFT substrates and outputting control signals for selectively connecting the data lines to the channel; A data line connection signal line configured to be parallel to the data line and output a control signal from the data line connection signal generating pad to the data line selection unit; And A second end of the data line is formed to extend, and includes a test signal detection pad configured to receive the test signal from the pixel failure detection line through the data line, And a wiring defect of the data line is detected by measuring a resistance value of a test signal applied to the test signal detecting pad.