Display panel packaging system and packaging method

Abstract

A display panel packaging system and a packaging method are disclosed. The display panel packaging system includes a display panel, a bonding device, a testing device and a controller. The display panel includes a plurality of pixel circuits and a substrate. The substrate is provided with a plurality of wires formed in cooperation with the pixel circuits to provide electrical connections of the pixel circuits. The bonding device is used to apply pressure to bond the pixel circuits to the substrate to form a display array on the substrate. The testing device is electrically coupled to the display array. The testing device is used to test the display array and receive sensing information from the display array. The controller is coupled to the bonding device and the testing device. During the bonding process of the display panel, the controller controls the bonding device according to the sensing information to adjust the pressure applied to the display panel.

Description

Technical Field

[0001] This invention relates to a system and a method, and more particularly to a display panel packaging system and packaging method. Background Technology

[0002] In existing display panel manufacturing, each control path in the individual pixel circuitry that may be prone to defects is often inspected individually, making the inspection process repetitive and tedious. Finally, after bonding, the entire panel must be illuminated again to check for any damaged or undetected defective pixel circuits from the bonding process. This further extends the overall production time of the display panel. Summary of the Invention

[0003] This invention provides a display panel packaging system and packaging method, which can perform real-time sensing of pixel circuits during bonding.

[0004] The display panel packaging system of the present invention includes a display panel, a bonding device, a testing device, and a controller. The display panel includes multiple pixel circuits and a substrate. Multiple conductive lines formed in conjunction with the pixel circuits are disposed on the substrate to provide electrical connections between the pixel circuits. The bonding device applies pressure to bond the pixel circuits to the substrate, thereby forming a display array on the substrate. The testing device is electrically coupled to the display array. The testing device is used to test the display array and receive sensing information from the display array. The controller is coupled to the bonding device and the testing device. During the bonding process of the display panel, the controller controls the bonding device based on the sensing information to adjust the pressure applied to the display panel.

[0005] The packaging method of the present invention can be used in a display panel. The display panel includes multiple pixel circuits and a substrate. The substrate is provided with multiple wires formed in conjunction with the pixel circuits to provide electrical connections for the pixel circuits. The packaging method includes applying pressure to bond the pixel circuits to the substrate to form a display array on the substrate; testing the display array and receiving sensing information from the display array; and adjusting the pressure applied to the display panel based on the sensing information during the bonding process of the display panel.

[0006] Based on the above, the display panel packaging system and method of the present invention can sense and adjust the bonding pressure while the pixel circuits are being bonded. Furthermore, after the bonding operation of the display array is completed, each display pixel can be tested to mark defective pixel circuits for subsequent elimination. Attached Figure Description

[0007] Figure 1 This is a block diagram of a display panel packaging system according to the present invention;

[0008] Figure 2This is a schematic diagram of the test device of the present invention testing the pixel circuit to obtain sensing information in Embodiment 1 of the present invention;

[0009] Figure 3 A flowchart illustrating the packaging method of Embodiment 1 of the present invention is shown;

[0010] Figure 4 This is a perspective view of a pixel circuit with horizontal offset according to Embodiment 1 of the present invention;

[0011] Figure 5 This is a schematic diagram of a pixel circuit with defects according to Embodiment 1 of the present invention.

[0012] Symbol Explanation

[0013] 1: Display panel packaging system

[0014] 10: Controller

[0015] 11: Joining equipment

[0016] 12: Testing equipment

[0017] 13: Display panel

[0018] 50: Table

[0019] 120: Probe

[0020] 130: Display array

[0021] 131: Substrate

[0022] C1: Capacitor

[0023] D1: Diode

[0024] Din: Display data

[0025] DX: Distance

[0026] EM: Laser signal

[0027] P1~P3: Control Path

[0028] PX: Pixel circuit

[0029] RST: Reset signal

[0030] S30~S32: Steps

[0031] SC: Scan signal

[0032] SC_R: Scan reset signal

[0033] SI: Sensing Information

[0034] T1~T5: Transistors

[0035] VDD: Operating voltage

[0036] VR1, VR2: Reference voltage

[0037] VSS: Ground voltage Detailed Implementation

[0038] Figure 1 This is a block diagram of a display panel packaging system 1 according to the present invention. The display panel packaging system 1 includes a controller 10, a bonding device 11, a tester 12, and a display panel 13. Generally, the display panel 13 includes a plurality of pixel circuits PX and a substrate (not shown) for carrying the pixel circuits PX. Figure 1 The substrate has patterned wires formed to match the pixel circuits PX, providing electrical connections for the pixel circuits PX. The bonding device 11 applies pressure to bond the pixel circuits PX to the substrate, forming a display array 130 on the substrate. The testing device 12 is electrically coupled to the display array 130 and can be used to test the display array 130 and receive corresponding sensing information SI from the display array 130. The controller 10, coupled to the bonding device 11 and the testing device 12, controls the bonding device 12 based on the sensing information SI during the bonding process of the display panel 13, adjusting the pressure applied to the display panel 13.

[0039] Specifically, since the substrate of the display panel 13 has patterned wires formed to match the pixel circuits PX, each pixel circuit PX needs to be bonded to its corresponding position by the bonding device 11 so that each pixel circuit PX can be driven to display in the display array 130 through the patterned wires. During the bonding process of each pixel circuit PX, the bonding device 11 bonds by applying pressure to each pixel circuit PX. Excessive or insufficient pressure will cause differences in electrical connection between the pixel circuit PX and the substrate, thus generating scratches (mura) on the display panel 13 and affecting the display quality of the display panel 13.

[0040] In some embodiments, the display panel packaging system 1 can improve the display quality of the display panel 13 by coordinating the bonding device 11 and the testing device 12 during the bonding of the display panel 13. Specifically, while the pixel circuit PX is being bonded to the substrate by the bonding device 11, the display panel packaging system 1 can use the testing device 12 to test the bonding pixel circuit PX to obtain corresponding sensing information SI. Therefore, the controller 10 of the display panel packaging system 1 can control the bonding device 11 based on the sensing information SI, so that the bonding device 11 applies appropriate downward pressure to bond the display panel 13.

[0041] Figure 2This is a schematic diagram illustrating how the testing device 12 of an embodiment of the present invention tests pixel circuits PX to obtain sensing information SI. Specifically, the testing device 12 includes a probe 120 or a probe card. The testing device 12 can directly contact the pads of the display panel 13 via the probe 120 to transmit signals with each pixel circuit PX in the display array 130 and to test the display array 130.

[0042] In some embodiments, the pixel circuit PX includes transistors T1 to T5, capacitor C1, and diode D1. Transistors T1, T2, and diode D1 are connected in series between the operating voltage VDD and the ground voltage VSS. Transistor T1 can be controlled by the laser signal EM to be either turned on or off, selectively providing current to drive diode D1.

[0043] Furthermore, transistors T3-T5 and capacitor C1 in the pixel circuit PX can also form control paths P1-P3, which, together with transistors T1 and T2, control the driving of diode D1. Mainly, the image display of the pixel circuit PX is controlled through control path P2. Control path P2 includes transistor T4 coupled to the gate of transistor T2. Transistor T4 receives display data Din at one end and provides the display data Din to the gate of transistor T2 according to the control of the scan signal SC. Further, capacitor C1 in the pixel circuit PX is coupled between the gate and source of transistor T2, and it can be used to store the display data Din provided through control path P2. In this way, the pixel circuit PX can store the display data in capacitor C1 through control path P2, and thereby control the driving current flowing through transistor T2, causing diode D1 to produce a display brightness corresponding to the display data Din.

[0044] To maintain display quality, control paths P1 and P3, respectively coupled to both ends of capacitor C1, are used to reset the voltage across capacitor C1. Specifically, control path P1 includes transistor T3, which is coupled to the upper plate of capacitor C1 and the gate of transistor T2. Transistor T3 is controlled by the scan reset signal SC_R, selectively providing the reference voltage VR1 to the upper plate of capacitor C1 and the gate of transistor T2. Additionally, control path P3 includes transistor T5, which is coupled to the lower plate of capacitor C1, the source of transistor T2, and the anode of diode D1. Transistor T5 is controlled by the reset signal RST, selectively providing the reference voltage VR1 to the upper plate of capacitor C1 and the node between transistor T2 and diode D1.

[0045] Therefore, for the pixel circuit PX to perform ideal display operations according to the control, it relies on the perfect engagement of all control paths P1 to P3. Applying too much or too little pressure during the engagement process will cause the control paths P1 to P3 to malfunction, resulting in a defective pixel circuit PX.

[0046] In some implementations, the test device 12 can detect the control paths P1 to P3 in the pixel circuit PX by testing the pads of the incoming reference signal VR1, display data Din, and reference signal VR2 to the pixel circuit PX. However, this implementation is time-consuming, requiring multiple checks for a single pixel circuit PX to confirm whether the connection of the control paths P1 to P3 is ideal, and it may even fail to rule out coupling abnormalities between transistors T1 and T2 and diode D1.

[0047] In some implementations, the test equipment 12 may test only the pads of the pixel circuit PX to which the ground voltage VSS is received. Specifically, any abnormal state of any of the three control paths P1 to P3 will affect the drive current received by diode D1, leading to display abnormalities in the display pixel PX. Therefore, instead of performing separate and multiple tests on control paths P1 to P3, the test equipment 12 can effectively determine whether the connection structure in the pixel circuit PX is abnormal by performing a single test on the pads of the pixel circuit PX to which the ground voltage VSS is received, including control paths P1 to P3, and even the overall connection of the series-connected transistors T1 and T2 and diode D1. Therefore, by testing the pads of the display panel 13 that receive the ground voltage VSS and receiving the sensing information SI, a rapid and effective assessment of whether the pixel circuit PX as a whole is defective can be performed.

[0048] certainly, Figure 2 The illustrated pixel circuit PX is merely one example of various implementations, used to illustrate the causes of defects in the pixel circuit PX and effective detection methods, and should not be construed as limiting the implementation of the pixel circuit PX. Adjustments or modifications made to the pixel circuit PX by those skilled in the art according to different design requirements should also be considered different implementations of the pixel circuit PX of this invention.

[0049] Figure 3 A flowchart illustrating a packaging method according to an embodiment of the present invention is shown. This packaging method can be applied to, for example, [missing information]. Figure 1 Display panel packaging system 1.

[0050] In step S30, the bonding device 11 may apply pressure to the pixel circuit PX to bond the pixel circuit PX to the corresponding position on the substrate. In this way, the patterned wires on the substrate can be connected to the corresponding nodes in each pixel circuit PX to provide data transmission for the pixel circuit PX during display operation.

[0051] In step S31, while the bonding device 11 applies pressure to press down and bond the pixel circuit PX onto the substrate, the test device 12 can perform tests on the display array 130 and receive sensing information SI from the display array 130. Specifically, the test device 12 can sense the display pixel PX by receiving the ground voltage VSS pads through the display array 130 and receive sensing information SI.

[0052] In step S32, the controller 10 of the display panel packaging system 1 can control the bonding device 11 based on the sensing information SI to adjust the pressure applied by the bonding device 11. Specifically, the bonding device 11 can gradually increase the pressure applied over time during the bonding process. The testing device 12 can continuously and in real-time monitor the display pixels PX in the display array 130 during the bonding process with gradually increasing pressure, and provide the sensed information to the controller 10, so that the controller 10 can adjust the pressure applied by the bonding device 11 based on the intensity of the sensing information SI.

[0053] In some embodiments, during the gradual increase of pressure applied by the bonding device 11, the controller 10 can determine whether the intensity of the sensing information SI falls within a preset intensity range, thereby determining whether the pressure applied by the bonding device 11 is appropriate for bonding the pixel circuit PX to the substrate of the display panel 13, ensuring a good electrical connection between the pixel circuit PX and the patterned wires on the substrate for display operation of the display array 130. Specifically, since the test device 12 tests the pixel circuit PX by providing a ground voltage VSS to the pads of the display array 130, the test device 12 can receive the current flowing through the diode D1 of the pixel circuit PX and provide it to the controller 10 as sensing information SI. In this way, the controller 10 can determine whether the current flowing through the diode D1 in the pixel circuit PX falls within a preset current range. When the controller determines that the intensity of the sensing information SI (i.e., the current flowing through the diode D1 in the pixel circuit PX) falls within the preset intensity range, the controller 10 can control the bonding device 10 to record the pressure magnitude and pause the increase of pressure. Furthermore, the controller 10 uses recorded pressure to bond other pixel circuits PX. In this way, the display panel packaging system 1 can obtain the appropriate pressure value by monitoring the bonding process of the display pixels PX to bond the entire display array 130.

[0054] In some embodiments, the controller 10 may, for example, monitor the bonding process of one or more pixel circuits PX to obtain one or more recorded pressure values, and control the bonding of the overall display array 130 by averaging the pressure values ​​of the one or more recorded values.

[0055] However, in the display panel packaging system 1, the process of monitoring the bonding process to adjust the pressure value improves the vertical offset between the pixel circuit PX and the substrate, making the vertical distance between the pixel circuit PX and the substrate fixed. But in some cases, there may also be a horizontal offset between the pixel circuit PX and the substrate.

[0056] Figure 4 This is a perspective view of a pixel circuit PX with a horizontal offset according to Embodiment 1 of the present invention. In this embodiment, the pixel circuit PX is placed on the substrate 131 and is horizontally offset from its preset position by a distance DX. This reduces the contact area between the pixel circuit PX and the connection structure provided on the substrate 131, resulting in a change in the resistance of the pixel circuit PX, which in turn affects the display operation.

[0057] In some embodiments, Figure 3 The illustrated packaging method can be further tested for each pixel circuit PX after step S32, that is, after the bonding operation of the overall display array 130 is completed with recorded pressure.

[0058] In detail, after the pixel circuit PX is bonded to the substrate, the controller 10 can test each pixel circuit PX of the display array to obtain sensing information SI corresponding to each pixel circuit. Furthermore, the controller 10 can compare the intensity of the sensing information SI with a preset intensity range and mark the pixel circuit PX corresponding to the sensing information that does not fall within the preset intensity range.

[0059] Figure 5 Table 50 is a schematic diagram of a defective pixel circuit PX according to Embodiment 1 of the present invention. Table 50 lists different defect types, and the corresponding display data and measured sensing information SI intensity provided upon detection. As shown in Table 50, the controller 10 can, for example, compare the measured current value with a preset current range and mark pixel circuits PX that do not fall within the preset current range as defective pixel circuits PX. These defects may originate from the resistance variation of the internal current connection structure of the pixel circuit PX caused by the horizontal or vertical offset between the pixel circuit PX and the substrate, thus causing the driving current flowing through the internal diode D1 in these defective pixel circuits PX to be too large or too small. Therefore, the controller 10 compares the intensity of the sensing information SI with a preset intensity range, judges the sensing information SI with excessively large or small intensity as abnormal, and marks the pixel circuit PX corresponding to these sensing information SI to facilitate subsequent replacement and repair.

[0060] Since the display panel packaging system 1 and packaging method perform the testing of each pixel circuit PX after the bonding operation of the display array 130 is completed, this operation sequence can also take into account the offset that the bonding operation may cause to each pixel circuit PX. Compared with testing each pixel circuit PX first and then performing the bonding operation, arranging the testing of the pixel circuit PX after the bonding operation allows for the detection of defective pixel circuit PX in the display panel 13 caused by various factors through a single test operation, avoiding repeated testing.

[0061] In summary, the display panel packaging system and method of the present invention can sense and adjust the bonding pressure simultaneously with the bonding of pixel circuits. Furthermore, after the bonding operation of the display array is completed, each display pixel can be tested to mark defective pixel circuits for subsequent elimination.

Claims

1. A display panel packaging system, comprising: The display panel includes: Multiple pixel circuits; and The substrate is provided with multiple wires that cooperate with the pixel circuits to provide electrical connections for the pixel circuits; A bonding device is used to apply pressure to bond the pixel circuits to the substrate in order to form a display array on the substrate; Test equipment, electrically coupled to the display array, is used to test the display array and receive sensing information from the display array; and A controller, coupled to the bonding device and the testing device, controls the bonding device based on the sensing information during the bonding process of the display panel to adjust the pressure applied to the display panel. The test device receives the sensing information by using the grounding voltage pad of the display array.

2. The display panel packaging system of claim 1, wherein during the bonding process of the display panel, the pressure applied to the display panel by the bonding device gradually increases.

3. The display panel packaging system as described in claim 2, wherein during the gradual increase of pressure, the controller determines whether the intensity of the sensed information falls within a preset intensity range. When the controller determines that the intensity of the sensing information falls within the preset intensity range, the controller controls the bonding device to record and pause the gradual increase of the pressure, and bonds the pixel circuits to the substrate with the recorded pressure.

4. The display panel packaging system of claim 1, wherein after the pixel circuits are bonded to the substrate, the controller tests the display array to obtain the sensing information corresponding to each pixel circuit, and marks the pixel circuit corresponding to the sensing information when the intensity of the sensing information does not fall within a preset intensity range.

5. A packaging method for a display panel, the display panel including a substrate and a plurality of pixel circuits, the substrate being provided with a plurality of wires formed in conjunction with the pixel circuits for providing electrical connections to the pixel circuits, the packaging method comprising: Pressure is applied to bond these pixel circuits to the substrate to form a display array on the substrate; The display array is tested and sensing information is received by the display array; as well as During the bonding process of the display panel, the pressure applied to the display panel is adjusted based on the sensing information. The display array receives the ground voltage pad, and the display panel receives the sensing information.

6. The packaging method as described in claim 5, comprising: During the assembly of the display panel, the pressure applied to the display panel is gradually increased by control.

7. The packaging method as described in claim 5, comprising: During the gradual increase of pressure, it is determined whether the intensity of the sensed information falls within a preset intensity range. When it is determined that the intensity of the sensing information falls within the preset intensity range, the pressure increase is recorded and paused, and the pixel circuits are bonded to the substrate with the recorded pressure.

8. The packaging method as described in claim 6, further comprising: After the pixel circuits are bonded to the substrate, the display array is tested to obtain the sensing information corresponding to each pixel circuit, and the pixel circuit corresponding to the sensing information is marked when the intensity of the sensing information does not fall within a preset intensity range.

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