JPH01102498A - Testing of active matrix substrate - Google Patents

Abstract

PURPOSE: To shorten the total time needed to test a substrate to about 1/100 compared with current methods by providing display elements for a test corresponding to pixel electrodes arrayed in another direction in a substrate, and coupling them with the said pixel electrodes as a circuit. CONSTITUTION: A test display means is arranged on the right side of the active matrix substrate 1, which is equipped with (n) test display elements 41-4n corresponding to the pixel electrodes 10 which are arrayed in the column direction. Each test display element is connected to the scanning electrode 30 corresponding to the pixel electrode 10 arrayed in the column direction. A pixel coupling means 50 is equipped with (n) probes 51, whose tips are brought into contact with the corresponding pixel electrodes to obtain circuit connection. The pixel electrode coupling means 50 is connected to one end of a test power source 70 through a flexible lead 61 and the other end of the power source 70 is connected to the respective elements 41-4n of the test display means 40. Consequently, the test time of the substrate can be shortened to approximately 1/100 as long as before.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for testing an active matrix substrate of a display panel device, particularly a liquid crystal display device. The present invention relates to a method for testing an active matrix substrate in which a display driving element is connected for each pixel between a scanning electrode that is commonly provided to pixel electrodes arranged in one direction in a column.

[Conventional technology]

As is well known, transistors are used to increase the area and display density of display panel devices.

Active matrix type display panel devices in which display driving elements such as diodes and nonlinear elements are incorporated into a substrate are advantageous, and their practical use is progressing from devices with relatively small dimensions. Display drive elements incorporated into the active matrix substrate of such a display panel device include two-terminal elements and three-terminal elements, an outline of which is shown in FIG.

The figure (Hata) shows an equivalent circuit of an active matrix substrate incorporating a two-terminal display drive element, in which a two-terminal display drive element 21 is provided attached to each of the pixel electrodes 10 arranged in a matrix. The two-terminal display drive element 21 is connected between each pixel electrode 10 and a scanning electrode 30 that is provided in common for the pixel electrodes arranged in the row direction as well as in the left-right direction. The scanning electrode 30 is a so-called vertical scanning electrode, and the horizontal scanning electrode 2 corresponding thereto is indicated by a in the figure.
As indicated by X, it has the shape of a strip having approximately the same width as the pixel electrodes extending in columns as shown on the other substrate facing the active matrix substrate. To display a certain pixel, each specific vertical scanning electrode 3
It is only necessary to apply a display voltage between 0 and the horizontal scanning electrode 2,
As a result, the two-terminal display drive element operates and the pixel electrode l
A display voltage is applied to the display medium between O and the horizontal scanning electrode 2, and the pixel is displayed.

FIG. 3B shows an equivalent path of an active matrix substrate incorporating a three-terminal display drive element 22, in which case both vertical scanning electrodes and horizontal scanning electrodes are incorporated into the active matrix substrate.

The scan electrode 30 in the figure is a horizontal scan electrode, and this and each pixel electrode 10 are the main terminals of the three-terminal display drive element 22.

For example, if the drive element is a field effect transistor, its source and drain are connected to each other.

The vertical scanning electrode 31 is a so-called WTM line, and the drive voltage for 0 display to which the control terminal of each three-terminal display driving element 22, for example, the gate of a field effect transistor, is connected is connected to the scanning electrode 8i30 and the other substrate side. A display voltage corresponding to the display signal applied to the vertical scanning voltage B131 and applied between the flat electric wire 3 indicated by a chain line in the figure is applied to the pixel electrode 10 via the three-terminal display drive element 22, and this Display is performed on the pixel corresponding to the intersection of the scanning electrode 30 to which a driving voltage is applied and the vertical scanning electrode 31 carrying a display signal.

Regardless of whether it is a 2-terminal or 3-terminal display drive element, it is a thin film element that can be easily incorporated into an active matrix substrate.
I-film diodes and MIM (metal-insulator-metal) thin film elements are used, and amorphous or polycrystalline silicon thin film transistors are used for the 3-terminal display drive elements, all of which have a thickness of about a few microns to a dozen microns. It is said to be the size of

The pixel electrodes, scanning electrodes, and display driving elements on the active matrix substrate as described above are fabricated through several photo processes in addition to their deposition or growth, as well as the connection film for interconnection. In relatively large display panel devices, defects may occur especially around display drive elements due to poor photo process conditions or lack of darkness, as the pixels are arranged in, for example, 400 rows and 640 columns. Even in the simplest black and white display, the total number of pixels is about 250,000, and in color display, it is three times this number.

On the other hand, even with the current advanced photoprocessing technology, it is still quite difficult to reduce the defect occurrence rate to 10-s or less, so several to dozens of defects may occur in one display panel device. This is unavoidable, and in practical terms, products with the number of defects below the allowable value are considered good products. The main types of defects are short-circuit defects in display drive elements, followed by open circuit defects.

Since it is unavoidable that some defects will occur in the active matrix substrate, it is necessary to test the substrate upon completion. The simplest test method is to perform a display test after assembling the display panel device, but for this purpose, the active matrix substrate and the other substrate are bonded together and a display medium is enclosed between them. Therefore, it takes time to assemble it, and if a defect occurs, the whole thing must be discarded.Therefore, before assembling it into a display panel device, the active matrix substrate alone is tested to determine its acceptability. An example of a conventional method for testing an active matrix substrate in such a single state is shown in FIG.

FIG. 7 shows a case where the display drive element 20 of the active matrix substrate 1 is a two-terminal element, and the probe 4a is used for testing.
A movable jig 4 equipped with a large number of is used.

The tips of the probes 4a are brought into contact with the pixel electrodes 10 arranged in the column direction, and each probe 4a is connected to a switched contact of a changeover switch 5 shown at the bottom of the figure.

The scanning electrodes 30 are commonly connected as shown in the figure, and a current detector 6 and a test voltage [7] are connected between this common connection point and the changeover contact of the changeover switch 5. As can be easily seen, each display driving element 20 is switched while sequentially switching the changeover switch 5.
The current flowing through is measured by the current detector 6, and when the current is too large, it is judged as a short-circuit defect, and when it is too small, it is judged as a disconnection defect. After completing the test of pixels lined up in one row, move the movable jig 4
is moved left and right as shown by arrow M in the figure, and this is repeated until all pixels on the active matrix substrate 1 are tested.

[Problem that the invention seeks to solve]

However, the conventional testing method described above works well as long as the active matrix substrate is small, but as the active matrix substrate becomes larger, the number of pixels to be tested increases, making the test very time-consuming. There is a problem that needs to be addressed. One of the reasons for this is that, as mentioned above, each display driving element is small and its normal current value is minute, at 10-9 to 10-th^, and this minute current is measured for each pixel. Since pass/fail must be determined, the test time per pixel becomes relatively long. Even if the current measurement method is devised and the changeover switch is made electronic to increase the switching speed, the test time per pixel cannot be determined accurately.
It takes 0.2 seconds. Now, if we assume that this time is 0.1 seconds/point and the number of pixels is about 250,000 as mentioned above, the time required for the test will be about 7 hours even excluding the time required to move the movable jig. Become.

The present invention aims to solve this problem and provide a practical method that can test active matrix substrates within a short time.

[Means for solving problems]

According to the present invention, this purpose is to provide a pixel electrode provided for each pixel arranged in a matrix as described above, and a scanning electrode provided in common to pixel electrodes arranged in one direction in one row and one column. As a means of testing an active matrix substrate in which display driving elements are connected pixel by pixel between the pixels 1! A test display means in which a test display element is provided corresponding to each pole, and a pixel electrode coupling means that can be coupled in a circuit at the same time to each of the pixel 1 electrodes arranged in the other direction are provided, and the pixel electrodes on the substrate 1. Each test display element of the pixel electrode coupling means and the test display means is connected in series to each series circuit of the display drive element and the scanning electrode, and the pixel electrode coupling means is connected simultaneously to each pixel electrode arranged in the other direction. A predetermined test voltage is applied in the coupled state, and at this time, each pixel lined up in the other direction is simultaneously tested from the display state shown by each test display element in the test display means, and the pixels arranged in the other direction are This is achieved by testing all pixels on the substrate while shifting the coupling state with the lined pixel electrodes in the one direction.

[Effect]

The effects of the above configuration will be explained below with reference to FIG. In the active matrix substrate 1 shown in FIG. An electrode 3o is provided, and a display driving element 2o, which is a two-terminal element in the case of the figure, is connected between each pixel electrode lO and the scanning electrode 3o.

The test display means 1 stage 4α shown on the right side of the active matrix substrate 1 in FIG. .about.4n, and each test display element is connected to the scanning electrode 30 corresponding to the pixel electrode 1o arranged in the column direction.The 0 pixel electrode coupling means 50 corresponds to the movable jig 4 in FIG. 8 above. For example, it is equipped with n probes 51, and by bringing the tips of these probes 51 into contact with the corresponding pixel electrodes, the circuit is simultaneously coupled to each of the pixel electrodes. ), all the probes 51 connected to the previous movable jig are commonly connected to the pixel electrode coupling means 50, and the pixel electrode coupling means 50 is connected to the test power supply 70 via a flexible lead 61. The other end of this test power supply 70 is commonly connected to each of the test display elements 41 to 4n of the test display means 40, so that the test voltage Vt of the test power supply 70 is The display elements 41 to 41t'l scan electrodes 30° are added to a series circuit consisting of a display drive element 201, a pixel electrode 10, and a pixel electrode coupling means 50.

As described above, since the pixel electrode coupling means 50 is simultaneously or all at once contact-coupled with each pixel electrode 10 arranged in the column direction via the probe 51, the test inside the test display means 50 is performed by applying the test voltage vt. Display elements 41 to 4n display images all at once. As will be seen from now on, the test display elements 41 to 4n of the test display means 50 of the present invention perform display in place of pixels arranged in a column direction, and depending on the display state of these test display elements, It is possible to determine the quality of the display drive element attached to the corresponding pixel electrode.

Therefore, it is desirable to configure each test display element to have almost the same structure as each pixel, so that the test display element can display the same display as the actual pixel, and display under conditions closest to the actual display. It is possible to determine the quality of the drive element or pixel.

Practically speaking, this judgment of pass/fail may be done visually, and for example, about 400 pixels are lined up in the column direction, but if there is a defect in even one pixel, a The presence of a defect can be easily detected from the display of the test display elements lined up. Of course, it is also possible to automate this defect detection.

This completes the test for the pixels arranged in one row.Next, as shown by the arrow M in ta+ in FIG. Alternatively, the pixel electrode coupling means 50 may be provided at the positions indicated by the vertical solid lines and dashed lines in the figure, and the
The pixel electrode coupling means 50 are respectively connected to the switching contacts of the changeover switch 60 shown in 1.1, and the switching contacts are connected to one end of the test power supply 70, and the switching command S
Pixel electrode coupling means 50 connected to the test power supply by S
can be made to select.

In the case of FIG. 1), the pixel electrode coupling means 50 is provided with a plurality of probes 51 as its coupling elements, but these probes 51 are supported by an insulator 52 and are insulated from each other. , are connected to the test display elements 41 to 4n of the test display means 40 via flexible leads 61, respectively. A common electrode of these test display elements 41 to 4n is connected to one end of a test power source 70, and the other end of the test power source 70 is commonly connected to all scanning electrodes 30. As a result, the test voltage Vt of the test power supply 70 is applied to the scan electrode 30. Display driving element 209 pixel electrode io, @element electrode coupling means 5
0 and each test display element 41 of the test display means 40
The 0 pixel electrode coupling means 50 is added to the 4n series circuit, displays on the test display elements 41 to 4n all at once as in the case of the same figure (al), and from which the quality of the pixels arranged in the column direction is determined. The sequence of movement in the direction of arrow M is shown in the same figure (
The same is true for Jl).

As can be seen from the above description, according to the present invention, as described in the above-mentioned configuration, a test display means is provided in which test display elements are provided respectively corresponding to pixel electrodes arranged in the other direction within the substrate. A pixel electrode coupling means that can be coupled in a circuit at the same time to each of the pixel electrodes arranged in the other direction is provided, and the pixel electrode coupling means and test are performed for each series circuit of the pixel electrode 1 display drive element and the scanning electrode on the substrate. By connecting the test display elements of the display means in series and applying a predetermined test voltage while simultaneously connecting the pixel electrode coupling means to each of the pixel electrodes arranged in the other direction, each test display of the display panel device is connected in series. Since the device displays the display corresponding to the pixels arranged in the column direction all at once, it is possible to test the quality of the pixels arranged in the column direction from the display state of the display device for testing in a very short time. This solves the problems of the present invention.

〔Example〕

Hereinafter, more specific embodiments of the present invention will be described with reference to FIGS. 2 to 5.

2 and 3 show the pixel amount 8 of the pixel electrode coupling means 50.
This shows an embodiment in which circuit coupling with i10 is performed by electrostatic capacitive coupling. FIG. 2 is a sectional view showing the nature of this capacitive coupling, and the lower part of the figure shows the glass substrate 1a of the active matrix substrate, the pixel electrode 109 provided on its surface, the display drive element 20, and the scanning electrode 30.
It is assumed that the left and right direction of the figure 0 in which is shown is the column direction of the active matrix substrate, and the scanning electrodes 30 extend in the row direction, which is the front and back direction of the figure. This is an electrode body in which a coupling electrode 8i53 made of metal or the like extending in the column direction is provided on the coupling electrode 52, and as shown in FIG. There are m pieces arranged in rows. As shown in FIG. 2, the pixel electrode coupling means 5o is disposed opposite to the coupling electrode 53 and the pixel electrode 10 with a distance of about several tens of degrees between them with a suitable spacer 52 interposed therebetween. The active matrix substrate 1 and the pixel electrode coupling means 50 are placed in a dish-shaped container, which is simply indicated by a dashed line in the figure, and this container contains a liquid dielectric material 54 such as alcohol having a high dielectric constant. Filled with pure water. The coupling electrode 53 and each pixel electrode 10 each form a capacitor via the dielectric 54, so that each coupling electrode 53 is capacitively coupled to each pixel electrode 10 arranged in the column direction at the same time. Note that instead of using such a liquid dielectric, a dielectric film may be applied to the surface of the coupling electrode, and this dielectric film may be brought into direct contact with the pixel electrode 10.

The active matrix substrate 1 shown in FIG.
It has the same configuration as the figure, with m rows above it.

Of the pixel electrodes 10 arranged in n rows, the n pixel electrodes 10 aligned in the column direction are each connected to a coupling electrode 5 of the pixel electrode coupling means.
The n scanning electrodes 30 are connected to the test display elements 41' to 4n of the test display means 40 shown on the right side of the figure. In this embodiment, the test display means 4o includes photodiodes 81 to 8n corresponding to each of the test display elements 41 to 4n.
are provided, and all of these photodiodes are connected in series and reverse biased by the voltage of a DC power supply 72. Each of the photodiodes 81 to 8n in this reverse bias state receives light from the test display elements 41 to 4n and becomes conductive when a display appears on the test display elements 41 to 4n. Such a photodiode can be made smaller by using, for example, an amorphous silicon thin film. On the other hand, each connection 1m8i of the pixel electrode connection means 50! 53 are respectively connected to the switched contacts of the changeover switch 60 shown below, and one of them is a changeover contact that receives the test voltage Vt in response to the changeover command SS given to the changeover switch 60 from calculation 8119G. Connected. The changeover switch 60 is a contact type for simplification of the diagram.
However, in reality, it is implemented as an electronic circuit to enable high-speed operation. The test power supply 71 generates a test voltage Vt in which a positive and negative square wave as shown in the frame is repeated, and receives a clock pulse CP specifying the period of this waveform from the calculation a90.

This test power supply 71 applies the above-mentioned test voltage Vt between the common electrode of the test display elements 41 to 4n of the test display means 4o and the coupling electrode 53 of the pixel electrode coupling means selected by the changeover switch 60. .

When a certain coupling electrode 53 is selected by the changeover switch 60 and receives the test voltage Vt, the test voltage Vt is applied to the pixel electrode 10 through capacitive coupling with the pixel electrodes 10 arranged below in the column direction, and the test display Test display element 4 of means 40
1 to 4n are displayed. In this example, the display of 41 to 4n of this test display element is bright when there is no defect in the corresponding pixel, and the display of corresponding photodiodes 81 to 8n is bright.
Since n is conductive, a current flows through the series-connected photodiodes 81 to 8n only when all pixels under the selected coupling electrode 53 are good, and this current is detected by the detection resistor 73 and calculated by the computer. 90. Therefore, the computer 9° can judge the quality of all the pixels arranged in the column direction based on the presence or absence of this current, and sequentially issues a switching command SS to the changeover switch 6o to select the coupling electrode 53 while switching the pixels in the corresponding column. Determine whether it is good or bad and store it.

In the case of this embodiment, if there is a defect in pixels arranged in a column, it is not possible to distinguish whether the defect is in only one pixel or in multiple pixels, but in reality, multiple pixels in one column are defective. This is usually sufficient in practice, since the probability that defects will occur in several pixels simultaneously is very small.

In the case of this embodiment, the pass/fail judgment of pixels arranged in a row can be made at high speed, and the changeover switch can also be made into an electronic circuit to increase the switching operation speed. It can be completed within minutes. Furthermore, since the capacitive coupling between the pixel electrode coupling means and the pixel electrode is more reliable than the contact coupling of the probe in the previous example, there is an advantage that reliability can be relied upon in the pass/fail determination result.

Note that the display of the test display element of the test display means 40 does not necessarily have to be bright when the corresponding pixel is good, but can be dark when the pixel is good and negative when it is defective. In this case, all of the photodiodes 81 to 8n may be connected in parallel, and when a current is detected in the parallel circuit, it may be determined that a pixel in the column is defective.

4 and 5 show an embodiment in which the pixel electrode coupling means and the pixel electrode are discharge-coupled. As seen in the cross-sectional view of FIG. 4, the pixel electrode coupling means 50 is connected to the active matrix substrate by approximately several hundred A metal line or strip 55 is provided which is stretched parallel to the substrate and separated from the substrate, and this metal strip 55 is supported by an insulator 56 at both ends, and is provided with a small protrusion 55a at a position corresponding to the pixel electrode IO on the substrate side. The pressure of the air or gas 57 is adjusted as appropriate so that discharge can occur under low voltage between the small protrusion 55a of the metal strip 55 and the pixel electrode IO. As can be seen from FIG. 5, the display driving element on the active matrix substrate 1 side in this embodiment is a three-terminal element 22 such as a transistor, and the scanning electrode 30 is connected to the n pixel electrodes 10 arranged in the column direction. A control line electrode 31 is provided for m pixel electrodes that are commonly provided and lined up in the row direction. Therefore, n metal strips 55 of the pixel electrode coupling means are provided in the row direction, and each of the six metal strips 55 is connected to a switched contact of the changeover switch 60. The test display means 40 is provided with m test display elements 41 to 4-, each of which is connected to the scanning electrode 3o. The test power source 70 is connected between the common electrode of the test display elements 41 to 4m of the test display means 40 and the switching contact of the changeover switch 60. The n control line electrodes 30 are commonly connected, and a partial voltage of the voltage of the test power supply 70 is applied via the adjustment resistor 74. This partial voltage is adjusted to a value suitable for testing.

A switching command SS is sent from the computer 90 to the changeover switch 60 to apply the test voltage V from the test power supply 70 to any metal strip 55.
When t is given, the small protrusion 55a of the metal strip 55 and the pixel electrode 10 below it are coupled by discharge, and a display is displayed on the test display elements 41 to 4 of the test display means 40 all at once. Ru. A charge accumulation type photosensor array 80 such as a COD method is incorporated in this test display means 40, and each display content of the test display elements 41 to 4 is converted into a clock pulse CP which is a kind of reading command. Data can be read from this optical sensor array 80 into a computer 90 synchronously. Therefore, in this embodiment, the computer 90 can store the display contents of the test display elements 41 to 4- or the judgment results based thereon for each test display element, that is, for each pixel, and can also store the display contents of the test display elements 41 to 4- for each pixel. can be displayed on the display device 91 of. Calculation [90] advances the test while switching pixel rows according to the switching command SS, and at the end of the test, the test results for all pixels in the active matrix board are stored in the computer 90,
Moreover, since it remains as a display on the display device 91, it is possible to comprehensively judge the quality of the tested active matrix substrate based on it.

In this example, a charge storage type optical sensor array is used, and reading from it is performed over time, so the test speed is slightly slower than the previous example shown in Figure 3, but it is possible to test all pixels on the board. It has the advantage that the results can be stored or displayed.

As can be seen from the description of the above embodiments, the present invention is not limited to these embodiments, and can be implemented in various Lj modes. After the display corresponding to the pixels lined up all at once, it is necessary to automatically detect the display contents using a photosensor or optical sensor array. It is possible to judge whether a pixel is good or bad, or to record the test results for all pixels on the board using photographic film.The method of connecting the 0 pixel electrode connecting means and the pixel electrode is also based on the probe in the embodiment. In addition to contact coupling, capacitive coupling, and discharge coupling, known coupling means can be used as appropriate, and the means for performing this coupling or shifting in the column direction may include mechanical methods and electrical methods in the embodiments, as well as both methods. It is also possible to use them together.Also, the way the test voltage is applied will naturally depend on the type of display panel device and display drive element, especially when the display drive element is composed of anti-parallel connected diodes. In this case, the display contents of the test display means may differ depending on the polarity of the test voltage applied. Therefore, if the test or pass/fail judgment is performed for each polarity of the test voltage, the direction of the disconnection defect can be determined. The test can also be conducted by distinguishing between genders.

〔Effect of the invention〕

As described above, in the present invention, between the pixel electrode provided for each pixel arranged in a matrix and the scanning electrode provided in common for the pixel electrodes arranged in one direction in one row and one column. When testing an active matrix substrate in which display drive elements are connected pixel by pixel, a test display means is provided in which test display elements are provided corresponding to pixel electrodes arranged in the other direction in the substrate and arranged in the other direction. A pixel electrode coupling means that can be coupled in a circuit at the same time as each of the pixel electrodes is provided, and each of the pixel electrode coupling means and the test display means is provided for each series circuit of the pixel electrode 1 display drive element and the scanning electrode on the substrate. The test display elements are connected in series and a predetermined test voltage is applied while the pixel electrode coupling means is simultaneously coupled to each of the pixel electrodes arranged in the other direction. By making the test display elements in the test display means simultaneously perform display corresponding to the pixels, it is possible to simultaneously complete the test on the pixels arranged in the predetermined direction based on their display states, thereby testing the active matrix board. The total time required for
It can be shortened to about 00. The test display means performs display in place of the pixels arranged in a predetermined direction, and rather than taking the trouble of measuring the minute current flowing through the display drive element of the pixel as in the past, it is possible to have the test display means perform display. The operation is faster (in fact, it is more accurate), and as described above, tests on a large number of pixels lined up in a predetermined direction can be completed simultaneously.

In particular, if each test display element has the same structure as each pixel, the display of the test display means will be substantially the same as the actual display of the pixel. This is equivalent to a test conducted when the active matrix substrate is assembled into a device. It can be said that.

The active matrix substrate testing method according to the present invention, which has such advantages, can exhibit cost and performance effects as display panel devices become larger and the number of pixels increases. It is expected that this will contribute to the further development of display panel devices in the future.

[Brief explanation of the drawing]

1 to 5 relate to the present invention, and FIG. 1 shows a test circuit including an active matrix substrate, which shows the principle of the method for testing an active matrix substrate according to the present invention when a probe is used as a pixel electrode coupling means. Figure, 2nd
The figure is a sectional view showing the coupling state between the active matrix substrate and the pixel electrode coupling means in an embodiment in which capacitive coupling is used as the pixel electrode coupling means, FIG. 3 is a test circuit diagram including the active matrix substrate in the embodiment, and FIG. FIG. 4 is a cross-sectional view showing the state of connection between the active matrix substrate and the pixel electrode coupling means in an embodiment in which discharge coupling is used as the pixel electrode coupling means, and FIG. 5 is a test circuit diagram including the active matrix substrate in this embodiment. be. FIG. 6 is an equivalent circuit diagram when a two-terminal element and a three-terminal element are used as display driving elements of an active matrix substrate, which is the object of the present invention. FIG. 7 is a test circuit diagram including an active matrix substrate, illustrating a conventional active matrix substrate testing method. In the figure, l near-active matrix substrate, la mini glass plate,
2: horizontal scanning electrode, 3: flat electrode, 4: movable jig, 4a:
Probe, 5X changeover switch, 6: Current detector, 7: Test voltage source, 10+ il element electrode, 2G+ display drive element, 21:
2-terminal display drive element, 22: 3-terminal display drive element, 30
: Scanning electrode, 31: Ill control type electrode 40: Test display means, 41-4@It 41-41n: Test display element, 50+pixel electrode coupling means, 51: Probe, 52 Ni glass plate, 52a Ni spacer, 53 : bonding electrode, 54: dielectric, 55: metal strip, 55a; small protrusion, 56: insulator, 57
: Discharge gas, 60: Changeover switch, ]0, 71: Test power supply, 72: DC power supply, 73: Detection resistor, 74: Adjustment resistor, 80: Optical sensor array, 81 to 8fi: Photodiode, 90: Computer , 91: display device, CP: clock pulse, D: discharge, SS: switching command, Vt+test voltage. Young JF person rI reason (Yamaguchi class)

Claims (1)

[Claims] 1) Display between a pixel electrode provided for each pixel arranged in a matrix and a scanning electrode provided in common for pixel electrodes arranged in one direction in either row or column. A method for testing an active matrix substrate in which drive elements are connected for each pixel, comprising: a test display means in which test display elements are provided corresponding to pixel electrodes arranged in the other direction in the substrate; The pixel electrode coupling means and test display means are connected to each series circuit of the pixel electrodes, display driving elements, and scanning electrodes on the substrate using a pixel electrode coupling means that can be coupled simultaneously with each of the pixel electrodes lined up in a circuit. Each test display element in the test display means is connected in series, and a predetermined test voltage is applied with the pixel electrode coupling means connected simultaneously to each pixel electrode arranged in the other direction, so that each test display element in the test display means shows It is possible to simultaneously test each pixel arranged in the other direction from the display state and to test all the pixels in the substrate while shifting the coupling state with the pixel electrode arranged in the other direction from the pixel electrode coupling means in the one direction. Characteristic testing method for active matrix substrates. 2) A method for testing an active matrix substrate according to claim 1, characterized in that each test display element of the test display means is connected to each scan electrode on the substrate side. . 3) In the test method described in claim 1, the pixel electrode coupling means is composed of mutually insulated connectors that are individually coupled to each pixel electrode arranged in the other direction, and each of the test display means A method for testing an active matrix substrate, characterized in that a display element is connected to each of the connectors of a pixel electrode coupling means. 4) The method for testing an active matrix substrate according to claim 1, wherein the test display element of the test display means is configured to have substantially the same structure as each pixel on the substrate side. 5) A testing method for an active matrix substrate according to claim I, characterized in that the pixel electrode coupling means is coupled to each pixel electrode by contact of a probe. 6) In the test method described in claim 1, the pixel electrode coupling means is formed as an electrode body, and the pixel electrode coupling means connects each pixel by making the electrode body face each pixel electrode with a dielectric interposed therebetween. A method for testing an active matrix substrate characterized by being electrostatically and capacitively coupled to an electrode. 7) A testing method for an active matrix substrate according to claim 6, characterized in that a liquid is used as the dielectric. 8) A testing method for an active matrix substrate according to claim 7, characterized in that an alcohol is used as the dielectric. 9) A testing method for an active matrix substrate according to claim 7, characterized in that pure water is used as the dielectric. 10) In the test method according to claim 1,
A method for testing an active matrix substrate, characterized in that the pixel electrode coupling means is coupled to each pixel electrode by a discharge between the pixel electrodes. 11) In the test method according to claim 1,
1. A method for testing an active matrix substrate, characterized in that by mechanically moving the pixel electrode coupling means, the coupling state of the pixel electrode coupling means with pixel electrodes arranged in the other direction is shifted in one direction. 12) In the test method according to claim 1,
A pixel electrode coupling means is arranged in parallel with a plurality of groups of pixel electrodes arranged in the other direction, and by switching the plurality of pixel electrode coupling means in a circuit, the pixel electrode coupling means arranged in the other direction A method for testing an active matrix substrate, characterized in that the bonding state with the substrate is shifted in one direction.