KR101005624B1 - Inspection apparatus of touch panel - Google Patents

Abstract

The present invention relates to an inspection apparatus for a touch panel, and more particularly, to an inspection substrate in a state in which an inspection substrate having the same pattern structure as that of a touch portion of a capacitive touch panel for which electrical characteristics are to be inspected is matched with each other. By indirectly inspecting the electrical characteristics of the touch panel through the terminals, the pin probe for contacting the interface of the touch panel is not used, thereby reducing maintenance costs and saving time for contact with the interface terminal of the touch panel. As a result, inspection time can be saved.

Touch Panel, Pattern Electrode, Resolution, Capacitance, Coupling, Indirect, Disconnection, Short Circuit

Description

Inspection device of touch panel {INSPECTION APPARATUS OF TOUCH PANEL}

The present invention relates to an inspection apparatus for a touch panel, and more particularly, to a test substrate in a state in which test substrates having the same pattern structure as that of the touch portion of the capacitive touch panel for which electrical characteristics are to be inspected correspond to each other. The present invention relates to an inspection apparatus for a touch panel that indirectly inspects electrical characteristics of the touch panel through terminals connected to each other.

In general, personal information processing devices such as personal computers, portable transmission devices, and the like use text, graphics, and the like by using various input devices such as a keyboard, a mouse, and a digitizer. Processing and so on.

In addition, in order to efficiently use various electronic devices, a touch panel for inputting a signal on the display surface of the display device without using a remote controller or the above-described input device is widely used. That is, the display surface of an electronic organizer, a flat panel display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electroluminescence (EL), and an image display device such as a cathode ray tube (CRT) It is installed so that the user can select desired information while viewing the image display device.

Such a touch panel may be classified into a resistive type, a capacitive type, and an electromagnetic induction method according to a method of sensing a touch.

Each method has different characteristics such as signal amplification problem, resolution difference, and difficulty in design and processing technology. Therefore, select a method that can take advantage of the advantages. Selection criteria should consider optical, electrical, mechanical, environmental and input characteristics, as well as durability and economy.

In the basic structure of the resistive touch panel, an upper transparent substrate having an upper electrode formed on a surface facing each other and a lower transparent substrate having a lower electrode formed thereon are bonded to each other by a spacer. Therefore, when any point is brought into contact with the surface of the upper substrate with a predetermined input means such as a pen or a finger, the upper electrode formed on the upper substrate and the lower electrode formed on the lower substrate are energized with each other, and then outputted by the resistance value at the position. After changing the voltage and reading the changed voltage value, the control device finds the position coordinate according to the change of the potential difference.

In addition, the basic structure of the capacitive touch panel includes a matrix type touch key array corresponding to the intersection of the driving electrode and the sensing electrode on one substrate, and when the driving signal is applied to the driving electrode, Since the degree of capacitive coupling is determined by measuring the amount of change delivered to the sensing electrode in response to a change in the drive signal, the degree of capacitive coupling between the electrodes at a given key depends on whether there are objects near the key. Is determined. Therefore, when the finger or the conductive pen contacts the touch array, the object coordinates are found because these objects change the electric field pattern between the electrodes.

In order to determine whether the touch panel accurately detects the position of the instruction content selected by the user, it is necessary to measure electrical characteristics of the electrode pattern.

1 is a view showing an inspection apparatus of a general touch panel.

As shown here, driving of the pattern electrode formed on the touch unit 12 in which the touch is made in contact with the interface terminal unit 14 of the touch panel 10 through the pin probe 22 of the measuring unit 20. When the electrical characteristic values at each intersection point are measured while the electrode and the sensing electrode are sequentially selected, the controller 30 compares the reference value and the measured characteristic value with respect to each intersection point to determine whether the corresponding intersection point is satisfied.

In this case, the driving electrode and the sensing electrode are formed on different layers that are insulated from each other at regular intervals, and overlap each other.

The technology described above refers to the background of the technical field to which the present invention belongs, and does not mean the prior art.

However, when measuring the touch panel in contact with the interface terminal of the touch panel through the pin probe to measure the touch panel as described above has the following problems.

First, the pin probe has a problem in that contact failure of the pin probe causes deformation due to repetitive contact operation.

Second, as the resolution and size of the touch panel increase, not only the number of wires increases but also the electrodes become narrower, so that the diameter of the pin probe is smaller than that of the present so as to correspond to the contact surface of the narrow electrode of high resolution. Due to the stiffness problem, there is a problem in that contact failure occurs on the contact surface of the electrode due to the deformation of the wire due to the weak bending moment.

Third, there is a problem that the pin probe and the pin probe without durability are easily damaged during pressure contact between the pin probe and the interface terminal of the touch panel, and the cost of the replacement is high.

Fourth, because the pin probe must be in pressure contact with the interface terminal of the touch panel, there is a problem that another defective factor is generated due to damage of the pattern electrode due to scratches due to contact.

The present invention has been made to improve the above problems, the present invention is for inspection in the state in which the inspection substrate having the same pattern structure as the touch portion of the capacitive touch panel to inspect the electrical characteristics corresponding to each other An object of the present invention is to provide an inspection apparatus for a touch panel that indirectly inspects electrical characteristics of the touch panel through terminals fixedly connected to the substrate.

According to an aspect of the present invention, there is provided an apparatus for inspecting a touch panel, wherein an interface terminal portion and an interface terminal portion and a pattern electrode of a touch portion are connected to each other so as to interface with a pattern electrode formed on a touch portion where a touch is made. An apparatus for inspecting a touch panel for inspecting electrical characteristics of a touch panel including a wiring unit, the apparatus comprising: a touch inspecting unit and an interface formed in the same position as a pattern electrode formed on the touch unit of the touch panel and disposed at a position corresponding to the touch unit An inspection substrate including a through electrode disposed at a position corresponding to the terminal portion; Measurement of measuring electrical characteristics by selectively applying an AC signal to the pattern electrode and the through-electrode of the touch inspection unit while being in close contact with the pattern electrode of the touch inspection unit to correspond to the pattern electrode of the touch inspection unit. part; And a controller which receives the electrical characteristic value measured by the measuring unit and compares the reference value with the reference value to determine whether the touch panel is good or bad.

In the present invention, the touch panel is characterized in that the capacitive type.

In the present invention, the test substrate is characterized in that the touch panel is seated.

In the present invention, the through-electrode includes a horizontal through-electrode corresponding to the interface terminal unit connected to the horizontal pattern electrode of the touch unit and a vertical through-electrode corresponding to the interface terminal unit connected to the vertical pattern electrode of the touch unit.

As described above, the present invention provides the electrical properties of the touch panel through a terminal fixedly connected to the test substrate in a state in which the test substrates having the same pattern structure as the touch unit of the capacitive touch panel to be tested for electrical properties are matched with each other. The property can be checked indirectly.

In addition, the present invention can indirectly measure the electrical characteristics of the touch panel through the terminal connected to the test substrate is not used a pin probe for contacting the interface terminal of the touch panel can reduce the maintenance cost.

In addition, the present invention can save the time for contact with the interface terminal portion of the touch panel by measuring the touch panel is placed in close contact with the test substrate to save the test time.

Hereinafter, an embodiment of an inspection apparatus of a touch panel according to the present invention will be described with reference to the accompanying drawings. In this process, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for clarity and convenience of description. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to the intention or convention of a user or an operator. Therefore, definitions of these terms should be made based on the contents throughout the specification.

2 is a view showing an inspection apparatus of a touch panel according to an embodiment of the present invention.

As shown here, the inspection apparatus of the touch panel includes a touch panel 10 as an inspection object, an inspection substrate 40, a measurement unit 20, and a controller 30.

The touch panel 10 is an interface terminal portion 14 for connecting and interfacing with the pattern electrodes formed on the touch portion 12 where touch is made, and for connecting the pattern electrodes of the interface terminal portion 14 and the touch portion 12. It is a capacitance type including the wiring portion 16.

In addition, the pattern electrodes of the touch unit 12 are formed on different layers in which the driving electrodes and the sensing electrodes arranged in the horizontal direction and the vertical direction are insulated from each other at regular intervals, and overlap each other.

At this time, each driving electrode and the sensing electrode of the pattern electrode is formed to be connected to an external control device (not shown) through the interface terminal 14 on one side.

The test substrate 40 is formed to allow the touch panel 10, which is a measurement target for inspecting electrical characteristics, to be seated, and is formed in the same manner as the pattern electrode formed on the touch unit 12 of the touch panel 10. It is disposed at a position corresponding to the touch inspecting portion 42 and the plurality of interface terminal portions 14 of the touch panel 10 disposed at a position corresponding to 12 to simultaneously apply or respond an AC signal to the interface terminal portion 14. A through electrode 50 for measuring a signal is formed.

The through electrode 50 includes a horizontal through electrode 52 corresponding to the interface terminal 14 connected to the horizontal pattern electrode of the touch unit 12 and an interface terminal 14 connected to the vertical pattern electrode of the touch unit 12. It includes a vertical through-electrode 54 corresponding to, and examines the case where the disconnection occurs in the wiring portion 16 of the touch panel 10 through the through-electrode 50.

In addition, the electrode patterns of the touch inspecting unit 42 and the measuring unit 20 are individually connected to each other, and may not correspond to the wiring unit 16 of the touch panel 10, which is an inspection object.

The measurement unit 20 is individually connected to the pattern electrodes of the touch inspection unit 42 of the inspection substrate 40 so that the measurement unit 20 closely contacts the pattern electrodes of the inspection substrate 40 and the pattern electrodes of the touch panel 10. AC signal is applied while the x-axis pattern electrode of the inspection substrate 40 is sequentially selected while the y-axis pattern electrode is sequentially selected, and the electrical characteristic value is measured or the AC signal is transmitted through the through electrode 50. After application, the electrical characteristics are measured while sequentially selecting the pattern electrode.

In this case, the electrical characteristic value may measure the capacitance between the pattern electrodes of the touch panel 10 corresponding to the test substrate 40 or measure the voltage value measured in the state where an AC signal is applied.

The controller 30 receives the characteristic value measured by the measuring unit 20 and compares it with the reference value to determine the electrical characteristic.

In this case, the reference value is typically set to a value obtained by collecting electrical characteristic values within a predetermined measurement range among electrical characteristic values measured for the plurality of touch panels 10.

As such, when the touch panel 10 is seated on the test substrate 40 and the pattern electrodes of the test substrate 40 and the pattern electrodes of the touch panel 10 are stacked side by side, the pattern electrodes of the test substrate 40 are stacked. And the capacitive coupling between the pattern electrode of the touch panel 10 and the pattern electrode of the inspection substrate 40 disposed so as to correspond when a disconnection or short circuit occurs in the pattern electrode of the touch panel 10. Even if the disconnection or the short circuit is measured through the touch inspecting section 42 of the inspection board 40 which is known to change the capacitance, it is possible to measure the disconnection or short circuit at the touch section 12 of the touch panel 10. It becomes possible.

The inspection process of the touch panel through the inspection device of the touch panel made as described above will be described in detail.

3 is a view showing a touch inspection unit of the inspection substrate according to an embodiment of the present invention.

First, it is possible to inspect a wide range of defects for the entire touch unit.

Short circuits x1 to x5 of the pattern electrodes formed on the touch inspection unit 42 of the inspection substrate 40 are short-circuited with one electrode, and short circuits y1 to y5 are short-circuited with another electrode. . In the state in which the touch panel 10 is seated on the test substrate 40, the electrical characteristic value between the two electrode groups is measured a plurality of times and set as a reference value. In this case, a method of electrically binding the five electrodes to one may be implemented in a circuit in the measuring unit 20.

After mounting the touch panel 10 on the inspection substrate 40 and then applying an AC signal to one electrode of the inspection substrate 40 in the same manner as described above and measuring the electrical characteristic value on the other electrode If the capacitance is changed between xy due to short circuit or disconnection between xy of the touch panel 10 or a pattern shape defect, a characteristic value different from a previously measured reference value may be measured, thereby detecting product defects.

Such a method can easily measure a wide range of defects on the entire touch unit 12, but cannot be inspected when both short circuits and disconnections exist individually on the pattern electrodes.

Second, individual defects on the pattern electrodes of the touch unit may be inspected.

When five electrodes are formed in the x-axis direction and five electrodes are formed in the y-axis direction, the intersection of the pattern electrodes of the touch unit 12 is 25.

Therefore, xy electrical characteristics of 25 intersection points in the touch inspection unit 42 of the inspection substrate 40 formed in the same manner as the touch unit 12 while the touch panel 10 is seated on the inspection substrate 40. Measure the value several times and set the reference value for each of the 25.

Thereafter, in the state in which the touch panel 10 is seated on the test substrate 40, the x-y electrical characteristic value is measured through the touch inspecting unit 42 and compared with the reference value for each intersection point to inspect whether there is a defect.

That is, when the voltage value measured after applying the AC signal is measured higher than the reference value, it may be determined that a short circuit has occurred in the x-axis pattern electrode and the y-axis pattern electrode which constitute the corresponding point. It may be determined that disconnection has occurred in the x-axis pattern electrode and the y-axis pattern electrode.

Third, defects of adjacent pattern electrodes in the same direction can be inspected.

In the state where the touch panel 10 is seated on the inspection substrate 40, the electrical characteristic value between the x-axis pattern electrodes of the touch inspection unit 42 is measured a number of times and set as a reference value, and then placed on the inspection substrate 40. In the state where the touch panel 10 is mounted, the electrical property value between the x-axis pattern electrodes is measured through the touch inspection unit 42 and compared with a reference value, thereby inspecting the pattern defect due to a short circuit or disconnection generated between the x electrodes. have.

That is, after applying an AC signal to the x1 pattern electrode, measuring the electrical characteristic value at the x2 pattern electrode, applying an alternating current signal to the x2 pattern electrode, and measuring the electrical characteristic value at the x3 pattern electrode. After setting the reference value of the electrical characteristic value for the adjacent pattern electrode for the settles the touch panel 10, the electrical characteristic value is measured and compared with the reference value to check the pattern defects between the adjacent pattern electrodes.

For the y-axis pattern electrodes, pattern defects between adjacent pattern electrodes can be inspected by the same method as described above.

Fourth, the defect generated in the wiring part of the touch part can be inspected.

An alternating current signal is applied between the through electrode 50 formed on the inspection substrate 40 and the pattern electrodes of the touch inspection unit 42 or between the transverse electrode 52 and the longitudinal through electrode 54 of the through electrode 50. After detecting the response signal change, it is possible to inspect whether the wire breaker 16 of the touch panel 10 is disconnected.

On the other hand, when a short circuit occurs in the wiring unit 16, the pattern electrode of the touch unit 12 is affected, so that the pattern electrode may be inspected as a short circuit defect in the second inspection method or the third inspection method.

As described above, the touch panel 10, which is an inspection object, corresponds to the inspection substrate 40, and an AC signal is applied to the inspection substrate 40 through the capacitance component existing between the touch panel 10 and the inspection substrate 40. By measuring the electrical characteristic value after the response is measured and compared with the reference value it can be checked whether there is an electrical defect for the touch panel 10 in a state not directly in contact with the touch panel 10.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and those skilled in the art to which the art belongs can make various modifications and other equivalent embodiments therefrom. I will understand. Therefore, the technical protection scope of the present invention will be defined by the claims below.

1 is a view showing an inspection apparatus of a general touch panel.

2 is a view showing an inspection apparatus of a touch panel according to an embodiment of the present invention.

3 is a view showing a touch inspection unit of the inspection substrate according to an embodiment of the present invention.

   -Explanation of symbols for the main parts of the drawings-

10: touch panel 12: touch unit

14: interface terminal portion 16: wiring portion

20 measuring unit 22 pin probe

30: control unit 40: inspection substrate

42: touch inspection unit 50: through electrode

52: horizontal electrode 54: vertical electrode

Claims (4)

Inspection of a touch panel for inspecting electrical characteristics of a touch panel including an interface terminal portion for connecting and interfacing with the pattern electrodes formed on the touch portion to be touched, and a wiring portion for connecting the interface terminal portion and the pattern electrode of the touch portion. In the device, An inspection substrate formed in the same manner as the pattern electrode formed on the touch unit of the thin touch panel and including a touch inspection unit disposed at a position corresponding to the touch unit and a through electrode disposed at a position corresponding to the interface terminal unit; The electrical characteristics are selectively connected to the pattern electrode of the touch inspector and selectively apply an AC signal to the pattern electrode and the through electrode of the touch inspector while being in close contact with the pattern electrode of the touch inspector and the pattern electrode of the touch inspector. A measuring unit measuring a value; And And a control unit which receives the electrical characteristic value measured by the measuring unit, compares the reference value with a reference value, and determines whether the touch panel is good or bad. The apparatus of claim 1, wherein the touch panel is of a capacitive type. The test apparatus of claim 1, wherein the touch panel is seated on the test substrate. According to claim 1, wherein the through electrode includes a transverse electrode corresponding to the interface terminal portion connected to the horizontal pattern electrode of the touch portion and a vertical through electrode corresponding to the interface terminal portion connected to the longitudinal pattern electrode of the touch portion Inspection device of the touch panel, characterized in that.

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