Display panel bonding pad detection device

Abstract

The present disclosure provides a binding pad detection device for a display panel, which belongs to the field of display technology. The display panel includes a row of multiple binding pads for binding and connecting with a control module. The binding pad detection device includes a crimping module, a detection module and an output module. The crimping module has a probe pair corresponding to the multiple binding pads one by one, and each of the probe pairs includes two probes for respectively crimping on the two ends of the corresponding binding pad; the detection module is electrically connected to the crimping module and includes at least one detection unit; the detection unit is used to detect whether the two probes of the probe pair are short-circuited by the corresponding binding pad; the output module is electrically connected to the detection module for outputting the detection result. The binding pad detection device can detect the binding pad after the electrical test.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a device for detecting binding pads of a display panel. Background Art

[0002] Display panels (such as organic electroluminescent display panels) require testing during the manufacturing process, such as electrical testing and module testing. However, defects in the bonding pads in the display panel's bonding area can go undetected during electrical testing, leading to defective products being transferred to the module stage and resulting in material waste.

[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the Invention

[0004] The purpose of the present disclosure is to overcome the above-mentioned deficiencies of the prior art and to provide a device for detecting the binding pads of a display panel, which can detect the binding pads of the display panel after electrical detection.

[0005] According to one aspect of the present disclosure, a device for detecting a binding pad of a display panel is provided, wherein the display panel includes a row of a plurality of binding pads for binding and connecting with a control module;

[0006] The bonding pad detection device comprises:

[0007] A crimping module, comprising probe pairs corresponding one-to-one to the plurality of binding pads, each probe pair comprising two probes for respectively crimping onto two ends of the corresponding binding pad;

[0008] A detection module, electrically connected to the crimping module, comprising at least one detection unit; the detection unit is used to detect whether two probes of the probe pair are short-circuited by the corresponding binding pads;

[0009] The output module is electrically connected to the detection module and is used to output the detection result.

[0010] According to one embodiment of the present disclosure, the crimping module includes a circuit board, and the probes are arranged on the circuit board; the circuit board is also provided with connecting wires corresponding to each of the probes; and the detection module is bound and connected to the connecting wires.

[0011] According to one embodiment of the present disclosure, the circuit board is a flexible circuit board.

[0012] According to an embodiment of the present disclosure, there are multiple detection units, which are arranged in a one-to-one correspondence with the multiple probe pairs; the detection unit is used to detect whether the two probes of the corresponding probe pair are short-circuited by the corresponding binding pad.

[0013] According to one embodiment of the present disclosure, the detection unit includes:

[0014] a power supply for applying a positive voltage and a negative voltage to the two probes of the probe pair, respectively;

[0015] a diode, wherein the anode of the diode is electrically connected to the positive electrode of the power supply, and the cathode of the diode is electrically connected to the negative electrode of the diode;

[0016] a current detection circuit, configured to detect the current flowing through the diode;

[0017] The determination circuit determines whether two probes of the probe pair are short-circuited by the corresponding binding pads according to a detection result of the current detection circuit.

[0018] According to an embodiment of the present disclosure, the voltage difference between the positive electrode voltage and the negative electrode voltage is greater than the threshold voltage of the diode.

[0019] According to one embodiment of the present disclosure, the power supply is further provided with a current limiting resistor.

[0020] According to one embodiment of the present disclosure, the output module includes:

[0021] a processor, configured to receive the determination results of each of the determination circuits and generate a detection result;

[0022] A display is connected to the processor and is used to display the detection result.

[0023] According to an embodiment of the present disclosure, the detection result includes the number of broken bonding pads or the labels of the broken bonding pads.

[0024] According to an embodiment of the present disclosure, the device further includes a machine platform and a carrying platform; the carrying platform is used to place the display panel to be tested;

[0025] The carrying platform, the crimping module, the detection module, the controller and the display are all arranged on the machine.

[0026] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification, are used to explain the principles of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0028] Figure 1 FIG. 1 is a schematic structural diagram of a display panel to be inspected in one embodiment of the present disclosure.

[0029] Figure 2 Schematic diagram of the principle of a bonding pad detection device in one embodiment of the present disclosure.

[0030] Figure 3 Schematic diagram of the principle of the connection relationship between the detection unit, the probe pair and the binding pad in one embodiment of the present disclosure.

[0031] Figure 4 Schematic diagram of the detection principle of the bonding pad detection device when the bonding pad is complete.

[0032] Figure 5 Schematic diagram of the detection principle of the bonding pad detection device when the bonding pad is broken.

[0033] Figure 6 Schematic diagram of the structure of a bonding pad detection device in one embodiment of the present disclosure. DETAILED DESCRIPTION

[0034] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art. Like reference numerals in the figures represent identical or similar structures, and thus their detailed descriptions will be omitted. Furthermore, the figures are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0035] Figure 1 Schematic diagram of the structure of a display panel during the preparation process. Figure 1, the display panel has a display area AA and a peripheral area BB surrounding the display area AA during the preparation process. In the display area AA, sub-pixels for displaying the picture and pixel driving circuits for driving the sub-pixels may be provided. In the peripheral area BB, a driving circuit for loading signals to the pixel driving circuit is provided. At least one end of the peripheral area BB is provided with a row of binding pads; the control module of the display device (such as a flexible circuit board of the control module) is bound and connected to the display panel through the binding pads so as to load signals to the display panel. During the preparation of the display panel, the display panel may also be provided with an electrical detection area CC, and detection pads are provided in the electrical detection area CC; the display panel needs to undergo electrical testing (ET test) during the preparation process, and these electrical testing processes are performed through the detection pads located in the electrical detection area CC.

[0036] The inventors discovered that some display panels that have passed electrical testing still have some lighting problems when they are assembled into display modules and undergo module testing; not only that, some display panels have poor reliability and a short lifespan. When analyzing the defects, it was found that during the production process of the display panel, due to sputtering, etching, etc., some binding pads will have broken wires (broken binding pads); these defects cannot be detected during the electrical testing process. However, the broken wires of the binding pads may cause the signal on the control module of the display device to be unable to be loaded to the display panel, thereby causing defects in the display module; in addition, water and oxygen channels are easily formed at the broken wire locations, thereby reducing the lifespan of the display panel.

[0037] To prevent display panels with broken bonding pads from entering the subsequent module manufacturing process and reduce material waste, the present disclosure provides a bonding pad detection device. This device can detect broken bonding pads during the electrical testing phase, allowing operators to intercept display panels with broken bonding pads.

[0038] See also Figure 2 , the bonding pad detection device comprises:

[0039] The crimping module 100 includes probe pairs PINS corresponding to the plurality of bonding pads PAD, each probe pair PINS including two probe PINs for crimping onto two ends of the corresponding bonding pad PAD;

[0040] The detection module 200 is electrically connected to the crimping module 100 and includes at least one detection unit TT; the detection unit TT is used to detect whether the two probes PIN of the probe pair PINS are short-circuited by the corresponding bonding pad PAD;

[0041] The output module is electrically connected to the detection module 200 and is used to output the detection results.

[0042] In the embodiment of the present disclosure, the bonding pad test can be performed after the conventional electrical test is completed and before entering the module process. Figures 3 to 5 During the inspection, the probe PIN of the crimping module 100 can be crimped onto the binding pad PAD of the display panel. In this way, if the binding pad PAD maintains electrical continuity, the two probe PINs of the probe pair PINS maintain electrical continuity through the binding pad PAD, that is, the two probe PINs of the probe pair PINS are short-circuited by the corresponding binding pad PAD. If the binding pad PAD is broken, the two probe PINs of the probe pair PINS cannot be electrically continuous through the binding pad PAD, that is, the two probe PINs are not short-circuited by the corresponding binding pad PAD. The detection unit TT detects whether the two probe PINs in the probe pair PINS are short-circuited through the corresponding binding pad PAD and transmits the result to the output module; the output module can determine whether the corresponding binding pad PAD is broken according to whether the two probe PINs of the probe pair PINS are short-circuited by the corresponding binding pad PAD, and then display the detection result.

[0043] In this way, inspectors can obtain test results from the output module and determine whether each bonding pad of the display panel has a broken wire, allowing them to intercept display panels with broken bonding pads. Furthermore, inspectors no longer need to classify display panels based on the test results; they can only intercept display panels with broken bonding pads. This can improve the bonding pad inspection rate without affecting the production line cycle time.

[0044] The structure, principle and effect of the bonding pad detection device provided by the embodiment of the present disclosure are further explained and illustrated below with reference to the accompanying drawings:

[0045] In one embodiment of the present disclosure, the crimping module 100 includes a circuit board, on which the probe pins are disposed; the circuit board is further provided with connection traces corresponding to each of the probe pins; and the detection module 200 is bound and connected to the connection traces. In one example, the circuit board of the crimping module 100 can be a flexible circuit board.

[0046] In one example, binding pins corresponding to the respective connection traces are further provided on the circuit board, and the detection module 200 can be bound and connected to the binding pins.

[0047] In one example, the probe PINs are arranged in two rows, wherein the probe PINs in one row are used for press-connecting with one end of the binding pad PAD; and the probe PINs in the other row are used for press-connecting with the other end of the binding pad PAD.

[0048] exist Figure 2 In the example detection module, the detection module 200 includes multiple detection units TT; the multiple detection units TT are arranged in a one-to-one correspondence with the multiple probe pairs PINS; the detection unit TT is used to detect whether the two probes PIN of the corresponding probe pair PINS are short-circuited by the corresponding binding pad PAD.

[0049] In some embodiments of the present disclosure, the detection unit TT includes:

[0050] A power supply DA, used for applying a positive voltage and a negative voltage to the two probes PIN of the probe pair PINS respectively;

[0051] a diode DB, wherein the anode of the diode is electrically connected to the positive electrode of the power supply, and the cathode of the diode is electrically connected to the negative electrode of the diode;

[0052] a current detection circuit DC, configured to detect the current flowing through the diode;

[0053] The determination circuit DD determines whether two probes PIN of the probe pair PINS are short-circuited by the corresponding bonding pads PAD according to the detection result of the current detection circuit.

[0054] Figure 3 Schematic diagram of the principle of the connection relationship between a detection unit TT, a probe pair PINS and a bonding pad PAD. Figure 4 Schematic diagram of the detection principle of the bonding pad detection device according to the embodiment of the present disclosure when the bonding pad PAD is intact. Figure 5 Schematic diagram of the detection principle of the bonding pad detection device according to the embodiment of the present disclosure when the bonding pad PAD is broken.

[0055] See also Figures 3 to 5Each bonding pad PAD needs to be inspected by a probe pair PINS, and the two probe PINs of the probe pair PINS are respectively crimped on the two ends of the bonding pad PAD; one probe is crimped on the end of the bonding pad close to the edge of the display panel, and the other probe is crimped on the end of the bonding pad away from the edge of the display panel. The power supply DA can load the anode voltage and cathode voltage to the two probe PINs of the probe pair PINS respectively. If the bonding pad PAD is intact, the two probe PINs are short-circuited through the bonding pad PAD; at this time, the diode DB is short-circuited by the bonding pad PAD, and there is no voltage difference between the two ends of the diode and it is cut off, and the current in the diode loop is very small. If the bonding pad PAD is broken, the two probe PINs of the probe pair PINS are not short-circuited by the bonding pad PAD; at this time, the positive voltage and negative voltage are respectively loaded on the two ends of the diode, and the voltage difference between the two ends of the diode can exceed the threshold voltage of the diode, and the diode is turned on, resulting in a large current in the diode loop.

[0056] In this way, the detection unit TT is equipped with a current detection circuit in the diode loop, which is used to detect the current flowing through the diode. Based on the detection results of the current detection circuit, the determination circuit can determine whether the two probes PIN of the probe pair PINS are short-circuited by the corresponding bonding pads PAD. If a large current is detected, it indicates that the bonding pads PAD are broken; if a small current is detected, it indicates that the bonding pads PAD are intact.

[0057] In one embodiment of the present disclosure, the threshold voltage of the diode is less than the voltage difference between the positive and negative voltages. For example, the negative voltage of the power supply is ground voltage GND (0V), and the positive voltage of the power supply exceeds the threshold voltage of the diode, for example, 6V.

[0058] In one embodiment of the present disclosure, the power supply is further provided with a current limiting resistor R. Thus, when the bonding pad PAD short-circuits two probes PIN, the current limiting resistor R can divide the voltage and reduce the current in the loop.

[0059] In one embodiment of the present disclosure, the current detection circuit may be a detection resistor connected in series with a diode circuit (a circuit formed by diode DB and power supply DA); the determination circuit may include a MOS transistor; and the connection node between the diode and the detection circuit is electrically connected to the gate of the MOS transistor. Thus, different currents passing through the diode will cause different voltages at the node between the diode and the detection circuit. This difference will cause different gate voltages of the MOS transistor, thereby turning the MOS transistor on or off.

[0060] Exemplarily, the negative voltage of the power supply is the ground voltage, the negative terminal of the power supply is electrically connected to the first end of the detection resistor, the second end of the detection resistor is electrically connected to the cathode of the diode, and the anode of the diode is electrically connected to the positive terminal of the power supply. The second end of the detection resistor is electrically connected to the gate of the MOS transistor. Taking the MOS transistor as an N-type MOS transistor as an example, when the bonding pad PAD is intact, the diode and the detection resistor are short-circuited, and the current through the detection resistor is substantially zero, which makes the voltage at the second end of the detection resistor substantially zero, and the MOS transistor remains cut off. When the bonding pad PAD is broken, the diode is turned on, causing a large current to pass through the detection resistor, which causes the second end of the detection resistor to have a large voltage, thereby turning on the MOS transistor.

[0061] In one embodiment of the present disclosure, the output module includes:

[0062] The processor 300 is configured to receive the determination results of each of the determination circuits and generate a detection result;

[0063] The display 400 is connected to the processor and is used to display the detection result.

[0064] In this way, each detection unit TT can send the determination result of the determination circuit to the processor, which generates a detection result after processing and analysis and displays it on the display.

[0065] In one embodiment of the present disclosure, the detection result includes the number of bonding pads PAD that are broken, or the numbers of bonding pads PAD that are short-circuited.

[0066] For example, in one example, the display may directly display how many bonding pads PADs on the display panel to be inspected are broken. For example, in another example, the display may directly display the numbers of the bonding pads PADs that are broken.

[0067] In the above example, the binding pad detection device of the embodiment of the present disclosure is explained and illustrated by taking the example of providing a one-to-one corresponding detection unit TT for each probe pair PINS. In the binding pad detection device of other embodiments of the present disclosure, the number of detection units TT in the detection module 200 may be less than the number of probe pairs PINS, for example, the number of detection units TT is half, one-quarter, one-eighth, one-sixteenth, one-thirty-second or other number of the number of probe pairs PINS. Specifically, one detection unit TT can be electrically connected to multiple probe pairs PINS through a circuit selector; when performing binding pad PAD detection, the circuit selector enables the detection unit TT to be electrically connected to the probe pairs PINS one by one and performs binding pad PAD detection until the detection of each binding pad PAD is completed. In this way, the number of detection units TT can be greatly reduced, and the cost of the detection module 200 can be reduced.

[0068] For example, 4 to 32 adjacent probe pairs PINS can be used as a detection group; the detection module 200 includes detection units TT and circuit selection circuits corresponding to each detection group. Each probe pair PINS in the detection group is electrically connected to the corresponding detection unit TT through the corresponding circuit selection circuit. When performing binding pad PAD detection, the circuit selection circuit can enable the corresponding detection unit TT to selectively be electrically connected to any one of the probe pairs PINS in the detection group. When the detection unit TT is electrically connected to the probe pair PINS, the detection unit TT can detect the state of the binding pad PAD corresponding to the probe pair PINS; thereafter, the circuit selection circuit enables the detection unit TT to selectively be electrically connected to another probe pair PINS in the detection group, and the detection unit TT can detect the state of the binding pad PAD corresponding to the new probe pair PINS; and so on and so forth until the detection of the binding pad PAD corresponding to each probe pair PINS in the detection group is completed.

[0069] In one embodiment of the present disclosure, see Figure 6 , the bonding pad detection device further includes a machine platform 600 and a carrying platform 500; the carrying platform 500 is used to place the display panel PNL to be tested;

[0070] The supporting platform 500 , the crimping module 100 , the detection module 200 , the controller and the display 400 are all disposed on the machine platform 600 .

[0071] In one embodiment of the present disclosure, a bonding pad detection device and an electrical detection device may share some modules, such as a carrier, machine platform, processor, and display. In other words, by adding the crimping module and detection module provided in an embodiment of the present disclosure to the electrical detection device, the electrical detection device can be transformed into a bonding pad detection device according to an embodiment of the present disclosure, thereby providing both electrical and bonding pad detection functions.

[0072] In the embodiments of the present disclosure, the display panel to be inspected may be a self-luminous display panel, such as an OLED display panel or a PLED display panel (polymer organic electroluminescent display panel). Of course, it may also be other types of display panels, such as a liquid crystal display panel, a micro diode display panel, or a mini diode display panel.

[0073] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the appended claims.

Claims

1. A device for detecting bonding pads of a display panel, characterized in that: The display panel includes a row of multiple bonding pads for bonding and connecting with the control module; The bonding pad detection device comprises: A crimping module, comprising probe pairs corresponding one-to-one to the plurality of binding pads, each probe pair comprising two probes for respectively crimping onto two ends of the corresponding binding pad; A detection module, electrically connected to the crimping module, comprising at least one detection unit; the detection unit is used to detect whether two probes of the probe pair are short-circuited by the corresponding binding pads; an output module, electrically connected to the detection module, and configured to output the detection result; The detection unit comprises: a power supply for applying a positive voltage and a negative voltage to the two probes of the probe pair, respectively; a diode, wherein the anode of the diode is electrically connected to the positive electrode of the power supply, and the cathode of the diode is electrically connected to the negative electrode of the diode; A current detection circuit is a detection resistor connected in series in the diode loop, used to detect the current flowing through the diode; The determination circuit includes a MOS transistor, a connection node between the diode and the current detection circuit, and is electrically connected to the gate of the MOS transistor. The determination circuit is used to determine whether the two probes of the probe pair are short-circuited by the corresponding binding pads based on the detection result of the current detection circuit.

2. The display panel bonding pad detection device according to claim 1, wherein: The crimping module includes a circuit board, and the probes are arranged on the circuit board; the circuit board is also provided with connection wires corresponding to each of the probes; and the detection module is bound and connected to the connection wires.

3. The display panel bonding pad detection device according to claim 2, characterized in that: The circuit board is a flexible circuit board.

4. The display panel bonding pad detection device according to claim 1, wherein: There are a plurality of detection units, which are arranged in a one-to-one correspondence with the plurality of probe pairs; the detection unit is used to detect whether two probes of a corresponding probe pair are short-circuited by the corresponding binding pad.

5. The display panel bonding pad detection device according to claim 1, wherein: A voltage difference between the positive electrode voltage and the negative electrode voltage is greater than a threshold voltage of the diode.

6. The display panel bonding pad detection device according to claim 1, wherein: The power supply is also provided with a current limiting resistor.

7. The display panel bonding pad detection device according to claim 1, wherein: The output module includes: a processor, configured to receive the determination results of each of the determination circuits and generate a detection result; A display is connected to the processor and is used to display the detection result.

8. The display panel bonding pad detection device according to claim 7, characterized in that: The detection result includes the number of broken bonding pads or the labels of the broken bonding pads.

9. The display panel bonding pad detection device according to claim 1, wherein: It also includes a machine platform and a carrying platform; the carrying platform is used to place the display panel to be tested; The carrying platform, the crimping module, the detection module, the controller and the display are all arranged on the machine.

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