JPH02165066A - Liquid crystal display panel inspection apparatus and method - Google Patents

Abstract

PURPOSE:To enable quick and accurate testing with a reduction in the number of probes used by a method wherein a signal is applied to a gate signal line through a gate IC control means, a plurality of source signal lines are used in common and a signal is applied through a probe to separate the signal lines by a working means. CONSTITUTION:The giving and taking of signals between a liquid crystal display panel 17 gate signal line 4 is performed without the use of a probe by a control means I and a gate IC control means 2. On the other hand, signals are applied to source signal lines 5 and 6 each with more than nine pieces thereof bundled through a probe of connection means 8 and 9 positioned respectively by positioning means 11 and 12. The source signal line wherein an abnormality is detected is separated with the irradiation of a laser by a working means means 13 provided with a positioning means 14 thereby enabling identifying of the source signal line involved in the abnormality.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates primarily to a liquid crystal display panel testing apparatus and method for testing active matrix liquid crystal display panels or arrays.

Conventional technology In recent years, as the number of yarns fed into liquid crystal display devices has increased, the number of scanning lines has increased, and the display contrast and response speed of conventional simple matrix liquid crystal display panels have decreased, so a switching element is required for each yarn feed. Active matrix type liquid crystal display panels with a layout of It is necessary to form tens of thousands or more thin film transistors (hereinafter referred to as TPT) as switching elements in the liquid crystal display panel. With current technology, it is difficult to form all the TPTs without defects. Therefore, it is necessary to perform an inspection after forming the liquid crystal display panel to determine whether it is good or bad. Therefore, there is a need for an inspection apparatus and method that can perform inspections at high speed.

Hereinafter, a conventional liquid crystal display panel inspection apparatus will be described with reference to the drawings. FIG. 5 is a block diagram of a conventional liquid crystal display panel inspection device (hereinafter referred to as inspection device). In FIG. 5, 17 is a liquid crystal display panel, and 7 is a stand for loading the liquid crystal display panel (hereinafter referred to as a loading stand).
, 21.20 is a probe for connecting with the gate signal line or source signal line of the liquid crystal display panel; 19.20 is a positioning means for positioning the probe to establish electrical connection with any signal line; 23 is probe 21
and 22, a resistance value measuring means for measuring the resistance value between 1 and 22;
8 is a positioning means 19.20 and a resistance value measuring means 23
It is a control means for controlling.

Hereinafter, the operation of the conventional inspection device will be explained.

The positioning means 19 and 20 move based on a positioning start signal from the control means 8, and press and position the probes 21 and 22 to a predetermined gate or source signal line. When the positioning is completed, the positioning means transfers a positioning completion signal to the control means 18. Next, the control means sends a measurement start signal to the resistance value measuring means 23 consisting of a resistance meter. Based on the signal, the resistance value measuring means 23 measures the resistance value between the probes 21 and 22, and transfers the resistance value to the control means 18. The control means 18 compares and determines whether a defect has occurred in the signal line to which the probes 21 and 22 are pressed, based on the magnitude of the resistance value. Defect detection is performed by carrying out the above operation by pressing the probes 21, 20 onto all the signal lines using the positioning means 19, 20.

Hereinafter, a method for inspecting a liquid crystal display panel using a conventional inspection device (hereinafter referred to as an inspection method) will be described. FIG. 6 is an explanatory diagram of a conventional inspection method. In FIG. 6, G, .about.G are gate signal lines, S, .about.S1° are source signal lines, TM, .about.TM,.

are TFTs, P, , -P, 9 are pictorial electrodes, and 24 is a short circuit defect (hereinafter referred to as a cross short) occurring at the intersection of the gate signal line G3 and the source signal line S3. Note that the liquid crystal display panel shown in FIG. 6 shows one in which one TPT is formed for each yarn feed. First, the probe 21 is pressed into contact with the source signal line S, and the probe 22 is connected with the gate signal line G,
press against. Next, the resistance value at the intersection of the gate signal line G and the source signal line S is measured using the resistance value measuring means 23. In the normal case, the resistance value is infinite, and in the case of a cross short, the wiring resistance of the signal line is measured. The above operation is performed sequentially for all gate signal lines by moving the probe 22. Similarly, the probe 21 is pressed against the source signal line S2, and the probe 22 is sequentially moved to measure the resistance value at the intersection between the source signal line S2 and the gate signal line.

Inspection is performed by measuring the resistance values at the intersections between the gate signal lines and source signal lines of all liquid crystal display panels using the probes 21 and 22 in accordance with the above method. 6th
In the liquid crystal display panel shown in the figure, the probe 21 is connected to the source signal line S.
When the probe 22 is pressed into contact with the gate signal line G3 and its resistance value is measured, a resistance value lower than usual is measured, so that the cross short 24 can be detected.

Problems to be Solved by the Invention In the conventional inspection apparatus and inspection method, since the probe is pressed into contact with each signal line of the liquid crystal display panel, it takes a very long time for positioning. For example, the gate signal line is 20
If the number of source signal lines is 0, the number of source signal lines is 200, and the positioning time per - point is 1 second, it will take 40,000 seconds, which is a long time of more than 10 hours per panel, and it cannot be used as a manufacturing process.

Further, since the probe is pressed into contact with the signal line, there is a problem that poor contact of the probe and damage to the liquid crystal display panel due to the probe tend to occur.

Furthermore, since the liquid crystal display panel is inspected by separating the gate signal line and the source signal line from short rings formed in the peripheral portion, the liquid crystal display panel becomes susceptible to static electricity. Therefore, there is a problem that static electricity flows into each signal line of the liquid crystal display panel during the inspection process, causing electrostatic damage to the TPT and the like.

Means for Solving the Problems The inspection device of the present invention comprises first and second connecting means for electrically connecting with a source signal line of a liquid crystal display panel, and a positioning means to which the connecting means is attached. , a signal application procedure connected to the first connection means and configured to apply a voltage or current to any source signal line; and a voltage on any source signal line connected to the second connection means. Alternatively, a signal detection means capable of detecting and measuring current, an application means capable of separating a plurality of short-circuited source signal lines by individually burning out the short-circuited portions using a laser beam, etc.; A gate signal line control means is provided for applying and controlling a signal that puts the connected TPT in an operating state (hereinafter referred to as an on-voltage) or a signal that makes the TPT in an inoperative state (hereinafter referred to as an off-voltage). It is something.

In addition, the inspection method of the present invention applies an on voltage or an off voltage to the gate signal line of the liquid crystal display panel, and detects a signal line superimposed on the source signal line with a plurality of source signal lines in common. ·Measure. When a signal is detected, the source signal lines are separated individually and the defect position is detected.

Operation In the inspection apparatus and inspection method of the present invention, a gate driving IC (hereinafter referred to as a gate IC) is connected to the gate signal line of the liquid crystal display panel.
It is called. ) is connected, the gate IC is operated, and an on voltage or an off voltage is applied to the gate signal line. Therefore, there is no need to make an electrical connection to the gate signal line using a connecting means such as a probe. Also, the source signal line is 1
Zero or more wires are short-circuited and made common at the peripheral portion, and a probe or the like is pressed into contact with the common portion to detect the voltage or current (hereinafter referred to as a defect signal) flowing through the defective portion of the liquid crystal display panel. If a defective signal is detected, each source signal line is separated using a laser beam or the like, and it is detected in which signal line the defective signal is generated.

Embodiment Hereinafter, an embodiment of the inspection apparatus of the present invention will be described with reference to the drawings. The first section is a block diagram of the inspection device of the present invention. In FIG. 1, 17 is an array in which a liquid crystal display panel or a counter electrode is not formed (hereinafter referred to as a panel), 7 is a stand for mounting panels, 4 is a gate signal line formed on the panel, 2 5.6 is a source signal line in which a plurality of lines are short-circuited in common at the periphery of the panel; 8 and 9 are Connection means such as a probe (hereinafter referred to as a probe) for electrically connecting with the source signal line of the panel; 10, a signal application means connected to the probe 8 and capable of generating a DC voltage; 11.
12 is a positioning means for positioning and press-contacting the probes 8 and 9 to arbitrary source signal lines; 13 is a processing means capable of melting and vaporizing a metal thin film using an optical means such as a laser beam; 14 is the processing means 13
15 is a signal detection means connected to the probe 9 to detect and measure the voltage or current applied to the probe 9; , 16 is a light beam such as a laser beam, and 2 is a control means for controlling each positioning means. It is clear that each positioning means is not necessary if the loading platform is constituted by an XY stage or the like and has a positioning function.

The operation of the inspection apparatus of the present invention will be explained below. The panels are loaded on a loading platform and fixed by an air chuck method or by fixing the periphery of the panels. The control means 1 transfers a control signal to the gate control means 2.

The gate control means 2 controls the gate drive IC so that a predetermined on-voltage or off-voltage is applied to the gate signal line of the panel.
control. The positioning means 11 and 12 move based on positioning signals such as coordinate value data from the control means 1, and press and position the probes at respective predetermined positions. The processing means controls an internal Q switch or an excitation lamp based on the laser irradiation signal from the control means 1 to turn on and off the laser light irradiation. Based on the positioning signal from the control means 1, the positioning means 14 operates an internally provided galvanometer or a linear motor to perform control so that the light beam 16 is irradiated to a predetermined location. The signal detection means detects and measures the defect signal applied to each source signal line based on the measurement start signal from the control means 1. Further, the signal applying means mainly generates a DC voltage and applies the voltage to a predetermined source signal line. The basic operation of the inspection apparatus of the present invention is to control the gate control means 2 and apply a predetermined on/off voltage to the gate signal line 4. Next, the probe 9 and, if necessary, the probe 8 are pressed into contact with each of the plurality of common source signal lines to establish an electrical connection. Next, the signal detection means 15
When a defect signal is detected, the source signal lines are individually separated using the processing means 13, and the probe 9 is pressed into contact with the source signal lines. Then, the signal detection means 15 detects and measures the defect signal,
When a defect signal is detected, controlling the gate control means 2;
By varying the application position of on/off voltage, defect mode/
Detect defect location.

Hereinafter, the inspection method of the present invention will be explained with reference to the drawings. FIG. 2, FIG. 3, and FIG. 4 are explanatory diagrams of the inspection method of the present invention. In Figures 2 to 4, G, -
G is a gate signal line, S1 to S. is the source signal line, T
S,,-TS,,,TM,.

~TM4q is TFT, P, ~P49 is yarn feeding bridge,
24 is a cross short, 25 is a short circuit defect that occurred between the gate and drain of TFT TS4z (hereinafter referred to as GD short), and 26 is a short circuit defect that occurred between the source and drain of TFT TM3g. (hereinafter referred to as S-D short). As is clear from FIGS. 2 to 4, the panel has two TPTs for one picture system, and has a redundant configuration so that if one TPT is defective, normal display can be performed using the other TPT.

It is particularly important to detect defective locations in the redundant panels described above. Note that every other source signal line is formed by being short-circuited in common, and although the number of common lines is shown to be very small in the drawing, usually more than ten signal lines are commonly used. Further, the number of gate signal lines and source signal lines are drawn to be very small in order to simplify the drawing.

First, a method for detecting and inspecting a cross short in a panel will be explained using FIG. First, the gate control means 2 controls the gate drive IC 3 and applies an off voltage to all gate signal lines. Note that, here, the off-voltage will be explained as a negative voltage, and the on-voltage will be explained as a positive voltage. Then, all TPTs are turned off. Next, the probe 9 is positioned and pressed against the a terminal to establish an electrical connection. At this time, the signal detection means is operated to detect whether a defective signal is superimposed. Note that the defect signal is a negative voltage or a negative current. Perform the above operations, c.
d... Do this for the terminal.

Since the cross short 24 has now occurred, a defect signal is detected when the probe 9 is pressed against the b terminal. Therefore, it is possible to detect that a cross short occurs at the intersection of the gate signal line and the block consisting of the source signal lines SZ+S4. Next, while the probe 9 remains positioned at the b terminal, the processing means 13 is used to cut at point A to separate the source signal line S2 at the b terminal. Thereafter, the defect signal is measured by the signal detection means. If a defect signal is detected, it is determined that a cross short has occurred in the source signal line S4, and if it is no longer detected, it is determined that a defect has occurred in the separated source signal line. Through the above procedure, it is possible to limit the location where the defect occurs to one of the plurality of common source signal lines. Next, the gate drive IC 3 is controlled by the gate control means 2, and an on-voltage is applied only to the gate signal line G, and the on-voltage application positions are changed to Gt, Gs, . . .
and shift.

In each state, a defect signal is measured using the signal detection means 15. When the ON voltage application position is applied to the gate signal line G3, the signal detection means 15 detects the ON voltage. Therefore, it can be detected from the gate signal line to which the on-voltage is applied and the source signal line to which the probe is positioned that a cross-over occurs at the intersection of the gate signal line G3 and the source signal line S4. Cross-short inspection is performed by performing the above method on all panels.

Next, a method for detecting and inspecting a G-D short circuit in a panel will be explained using FIG. First, the gate control means 2 controls the gate drive IC 3, and applies an on/off voltage so that one of the two yarn feeding TPTs is turned on and the other is turned off. Now, explanation will be given assuming that an off voltage is applied to the odd-numbered gate signal lines and an on-voltage is applied to the even-numbered gate signal lines. Next probe 9
a.

The terminals b, c, d, . Now, G-D short 25 has occurred and TFT TS43 is on, so G, →
Since a current path of GD short 25→TS43→S3 is generated, a defect signal is detected when the probe 9 is pressed against the a terminal. Therefore, it can be seen that a defect has occurred in the TPT on the source signal line connected to the a terminal.

Next, using the processing means 3, the source signal line is cut from the terminal A in order from the point A. Now, even if the part A is cut, a defect signal is detected by the signal detection means 15. It can be seen that a defect has occurred in the TPT connected to the source signal line S3 since no defect signal is detected when the portion A is cut. Next, the probe 9 is pressed against the source signal line S3. Further, the gate drive IC 3 is controlled to apply an ON voltage only to the gate signal line G, and while sequentially shifting the ON voltage application position, it is measured whether a defect signal is detected in each state. Now, when an on-voltage is applied to the gate signal line G4, a defect signal is detected through the above-mentioned path, so that the location where the defect occurs can be detected.

However, in this case, TPT's TM3. Even if a GD defect occurs in G4→GD defect→TMff□→S.

Therefore, in order to judge which one is, the probe 9 is pressure-contacted to the b terminal, and the work area is moved to the machining means 1.
Cut at 3. Next is the gate signal line G.

When on voltage is applied to the signal detecting means 15, if a defective signal is detected, TS of TFT, GD short is detected, and if not detected, TM of TFT, GD short of □ is limited/detected. can do.

The G-D short circuit in the panel can be detected and inspected using the above method.

Next, a method for detecting and inspecting a panel SD short circuit will be explained using FIG. First, the gate drive IC 3 is controlled by the gate control means 2, and an on/off voltage is applied to each gate signal line so that one of the two yarn feeding TPTs is turned on and the other is turned off. . Now, explanation will be given assuming that an on voltage is applied to the odd-numbered gate signal lines and an off-voltage is applied to the even-numbered gate signal lines. Next, press the probe 9 to the b terminal and press the probe 9 to the a terminal. In addition, by the same method, the probe 8
is connected to the d terminal and the probe 8 is pressed to the C terminal, so that the signal from the signal applying means 10 is applied to one source signal line in the measurement block, and the signal is applied to the source signal line adjacent to the source signal line in the measurement block. One test is performed by sequentially moving the probe 8°9 so that it is connected to the detection means 15. The signal applied from the signal applying means 10 is normally a positive DC voltage. When the probe 8 is pressed into contact with the b terminal and the probe 9 is pressed into the a terminal, and a voltage is applied from the signal application means 1o, TS3□ of the TPT is in the on state.SD
Since a short circuit 26 has occurred, S z −T S
sz= P 'rz" S D stain) 26 → S
3 current paths are generated, and a defect signal is detected by the signal detection means 15. Next, in order to detect which source signal line in this measurement block has a defect, the processing means 13 is used to irradiate a laser beam to the part A and cut it from the terminal A. Now, even if the part A is cut, a defect signal is detected by the signal detection means 15, so the part B is cut. Then, the defect signal is no longer detected. Next, connect the probe 9 to the source signal line S.

Apply pressure to the chisel. Further, the gate drive IC 3 is controlled to apply an ON voltage only to the gate signal line G, and while sequentially shifting the ON voltage application position, it is measured whether a defect signal is detected in each state. Now, when an on-voltage is applied to the gate signal line G3, a defect signal is detected through the above-mentioned path, so that the location of the defect can be detected. By the above method, it is possible to detect and inspect the panel SD:> boat.

Although the inspection device and inspection method of the present invention target liquid crystal display panels, they are not limited to this.
It is clear that similar effects can be obtained even when considering the liquid crystal display array before liquid crystal injection.

Effects of the Invention In the inspection apparatus and inspection method of the present invention, a gate control means is used to apply an on or off voltage to the gate signal line of the panel. Therefore, there is no need to use a probe or the like to make an electrical connection to the gate signal line. Therefore, the inspection device has the effect of greatly reducing the number of probes used and eliminating the problem of poor contact, and the inspection method has the great effect of being able to perform inspections at extremely high speed.

Further, since the electrical connection to the source signal line is made by using a plurality of source signal lines in common, forming blocks, and pressing the probes, the same effects as described above can be obtained in the inspection apparatus and the inspection method. In addition, even though the source signal lines are divided into blocks and inspected at very high speed, each source signal line can be separated using processing means, making it possible to identify the defective position where the defective signal flows. Can be done.

Commonly shorting the source signal lines has a great effect on preventing panel damage due to static electricity.

Since the inspection apparatus and inspection method of the present invention performs separation only at the minimum necessary locations, panels can be manufactured with high anti-static properties up to the final process of the panel, which is highly effective.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the inspection device of the present invention, and FIGS.
5 is an explanatory diagram of the inspection method of the present invention, FIG. 5 is a block diagram of a conventional inspection apparatus, and FIG. 6 is an explanatory diagram of the conventional inspection method. 1.18...control means, 2...gate IC control means, 3...gate IC14...
...Gate signal line, 5゜6...Source signal line,
7... Loading platform, 8, 9... Connection means,
10... Signal application means, 11.12.14.1
9゜20...Positioning means, 13...
Processing means, 15... Signal detection means, 16...
...Light ray, 17...Liquid crystal display panel, 21,
22...Probe, 23...Resistance value measuring means, 24...Cross short, 25...
...G-D short, 26...S-D short, GI)G, ...gate signal line, S I"
"' S I O"'"'Source signal line, TS...
TM+ I-TS-9, TMsq...
・TFT, P,, -P,,...Picture type electrode. Agent's name Patent attorney Shigetaka Awano Haka 1 person 1 - Controller 2 - K) IO separate controller 3 --- Gate Station LC 4- = Gate No. 1 8 5.6 --- Source signal Section 7-・-Loading platform 8, 9- 扉剉地chi role 10-Signal stamp U hand role If, ! 2.74-411 Next means 13-7jtr
Two children's role 15 - Signal detection '4 - Role 16 - Hikari, house I7 - Sleeping item table Hoba Kishitomi 5 figure I8 - 11 wholesale I hand f husband 19, 20 --- I, standing 4 Ra dog me hand role 2
/, 22---7・loaf

Claims (7)

[Claims] (1) A connecting means for electrically connecting with a source signal line formed on a liquid crystal display panel, a positioning means for positioning the connecting means, and a connecting means connected to the connecting means to generate and apply a predetermined signal. A signal applying means, a signal detecting means connected to the connecting means, a processing means for separating the plurality of short-circuited source signal lines, a positioning means for positioning the processing means, and a gate formed on a liquid crystal display panel. 1. A liquid crystal display panel inspection device comprising: gate signal line control means for applying a predetermined voltage to a signal line. (2) The gate signal line control means applies a predetermined voltage to the gate signal line by controlling a gate drive IC connected to the gate signal line of the liquid crystal display panel. LCD panel inspection equipment. (3) The liquid crystal display panel inspection apparatus according to claim (1), wherein the processing means includes a laser beam generating means. (4) The liquid crystal display panel inspection apparatus according to claim (1), wherein the signal detection means is capable of measuring at least one of the magnitude and polarity of current and the magnitude and polarity of voltage. (5) A voltage is applied to the gate signal line to activate or deactivate the switching element connected to the signal line, and the voltage is superimposed on the signal line with multiple source signal lines in common. If a signal is detected on the signal line, the source signal lines are individually separated using optical, chemical, or mechanical means, and the signals superimposed on each signal line are separated. A method for inspecting a liquid crystal display panel, characterized in that inspection is performed by detection. (6) The method for inspecting a liquid crystal display panel according to claim (5), wherein a predetermined voltage is applied to the gate signal line by operating a gate driving IC connected to the gate signal line. (7) The method for inspecting a liquid crystal display panel according to claim (5), wherein a plurality of common source signal lines are separated using optical means.