Method for detecting damage to touch display panel

Abstract

The invention provides a method for detecting damage of a touch display panel. The touch display panel comprises a plurality of sensing pads and a plurality of signal lines. The method comprises the following steps: selecting at least one first element from the sensing pad and the signal line as an element to be tested; applying a first voltage to the to-be-tested element and receiving a feedback signal from the to-be-tested element, wherein the feedback signal comprises voltage information or capacitance information of the to-be-tested element; and judging whether the to-be-tested element is damaged according to the feedback signal.

Description

Technical Field

[0001] This invention relates to a method for detecting damage to a touch display panel. Background Technology

[0002] TDDI (Touch and Display Driver Integrated Chip) is a touch technology solution that integrates display driver circuitry and touch driver circuitry onto a single chip. In the event of touch malfunctions (such as sensor failure) or display malfunctions (such as source or gate line damage), since there is no detection mechanism within the chip, detection is typically achieved through manual touch or visual inspection. To improve safety, the automotive industry is working to enhance panel touch and display monitoring capabilities through chips, enabling systems to automatically report anomalies to provide warnings and enhance driving safety. Summary of the Invention

[0003] This invention provides a method for detecting damage to a touch display panel, which can detect abnormalities in the components of the touch display panel.

[0004] This invention provides a method for detecting damage to a touch display panel, wherein the touch display panel includes multiple sensing pads and multiple signal lines. The method includes: selecting at least one first element from the sensing pads and signal lines as an element under test; applying a first voltage to the element under test and receiving a feedback signal from the element under test, wherein the feedback signal includes voltage information or capacitance information of the element under test; and determining whether the element under test is damaged based on the feedback signal.

[0005] To make the foregoing better understood, several embodiments accompanied by accompanying drawings are described in detail below. Attached Figure Description

[0006] Figure 1 This is a block diagram of a touch display device according to an embodiment of the present invention.

[0007] Figure 2 This is a schematic diagram of the detection mechanism according to an embodiment of the present invention.

[0008] Figure 3 This is a schematic diagram of a detection mechanism according to another embodiment of the present invention.

[0009] Figure 4 This is a schematic diagram of a detection mechanism according to another embodiment of the present invention.

[0010] Figure 5A This is a schematic diagram of a detection sensing pad according to an embodiment of the present invention.

[0011] Figure 5B These are different waveforms of the LFD signal shown in accordance with embodiments of the present invention.

[0012] Figure 6 This is a schematic diagram of a detection sensing pad according to another embodiment of the present invention.

[0013] Figure 7 This is a schematic diagram of the detection source line according to an embodiment of the present invention.

[0014] Figure 8 This is a schematic diagram of a detection source line according to another embodiment of the present invention.

[0015] Figure 9 and Figure 10 These are schematic diagrams of detection gate lines according to different embodiments of the present invention.

[0016] Figure 11 This is a schematic diagram of a detection source line according to another embodiment of the present invention.

[0017] Figure 12 This is a flowchart illustrating the steps of a method for detecting damage to a touch display panel according to an embodiment of the present invention.

[0018] Figure 13 This is a schematic diagram illustrating an open circuit of the component under test according to an embodiment of the present invention.

[0019] Figure 14 This is a schematic diagram illustrating a short circuit between the device under test and the adjacent source line according to an embodiment of the present invention.

[0020] Figure 15 This is a schematic diagram illustrating the simultaneous detection of multiple source lines according to an embodiment of the present invention.

[0021] Figure 16 This is a schematic diagram illustrating the sequential detection of multiple source lines according to an embodiment of the present invention.

[0022] Figure 17 This is a schematic diagram illustrating the sequential detection of multiple gate lines according to an embodiment of the present invention.

[0023] Figure 18 This is a schematic diagram illustrating the sequential detection of multiple sensor pads according to an embodiment of the present invention.

[0024] Explanation of icon numbers

[0025] 100: Touch display device

[0026] 110, 510, 1110: Touch display panel

[0027] 112, 512, 1112, 1112_1, 1112_2, 1112_3: Sensor pads

[0028] 114, 514, S0~S11: Source lines

[0029] 116, 516, G0~G2: Gate lines

[0030] 120, 520, 1120, 1120': Driver circuit

[0031] 122, 522, 1122: Switching circuits

[0032] 122_1, 122_3: First switching circuit

[0033] 122_2, 122_4: Second switching circuit

[0034] 524, 1124: Analog front-end circuit

[0035] 526, 1126: Processor circuit

[0036] Cs1~Cs7、CsN: Capacitance values

[0037] DC: Direct current signal

[0038] DUT: Component Under Test

[0039] FB: Feedback Signal

[0040] Gn: Scan signal

[0041] GND: Grounding voltage

[0042] HiZ: High impedance state

[0043] LFD: No-load drive signal

[0044] S100, S110, S120, S130: Method Steps

[0045] Sn: Data signal

[0046] V1: First voltage

[0047] V2: Second voltage Detailed Implementation

[0048] The following embodiments are provided to describe the present invention in detail, but the invention is not limited to the provided embodiments, and the provided embodiments can be suitably combined. The terms "coupling" or "connecting" as used in this specification (including the claims) may refer to any direct or indirect connection. For example, "the first device is coupled to the second device" should be interpreted as "the first device is directly connected to the second device" or "the first device is indirectly connected to the second device through other devices or connecting members." Additionally, the term "signal" may refer to current, voltage, charge, temperature, data, electromagnetic waves, or any one or more signals.

[0049] Figure 1 This is a block diagram illustrating a touch display device according to an embodiment of the present invention. (Refer to...) Figure 1 The touch display device 100 includes a touch display panel 110 and a driver circuit 120. The driver circuit 120 is used to drive the touch display panel 110 to perform display operations and touch sensing operations. In an embodiment, the driver circuit 120 may be a touch and display driver integrated chip, but the present invention is not limited thereto.

[0050] In this embodiment, the driver circuit 120 is also used to perform a method for detecting damage to the touch display panel 110. Damage to the touch display panel 110 refers to an open circuit in the sensing pad, source line, or gate line itself, or a short circuit between the sensing pad, source line, or gate line and an adjacent sensing pad, source line, or gate line.

[0051] Specifically, Figure 2 This is a schematic diagram illustrating the detection mechanism according to an embodiment of the present invention. (Refer to...) Figure 1 and Figure 2 The touch display panel 110 includes a plurality of sensor pads 112 for sensing touch events. The driver circuitry 120 includes a plurality of switching circuits 122 for selecting signals. For clarity, Figure 2 Only one sensing pad 112 and one switching circuit 122 are shown, but the number of sensing pads 112 and switching circuits 122 is not intended to limit the invention. In embodiments, the switching circuit 122 may include at least one selector for transmitting and receiving signals, but the invention is not limited thereto.

[0052] During testing, the sensing pad 112 can act as a device under test. The switching circuit 122 switches to select a first voltage V1 to be applied to the sensing pad 112 and receives feedback signals FB from the sensing pad 112 at different times. During another testing period, the sensing pad 112 can act as a reference element to detect other sensing pads. The switching circuit 122 switches to select a second voltage V2 to be applied to the sensing pad 112, or to place the sensing pad 112 in a floating state or a high-impedance state HiZ. In an embodiment, the second voltage V2 can be ground voltage, but the invention is not limited thereto.

[0053] Figure 3 This is a schematic diagram illustrating a detection mechanism according to another embodiment of the present invention. (Refer to...) Figure 3 The touch display panel 110 also includes multiple source lines 114 and multiple first switching circuits 122_1 for display operation, and adds multiple second switching circuits 122_2 for damage detection. For clarity, Figure 3 Only one first switch circuit 122_1 and one second switch circuit 122_2 are shown, but the number of first switch circuits 122_1 and second switch circuits 122_2 is not intended to limit the invention.

[0054] In this embodiment, the first voltage V1 can be a load-free driving (LFD) signal, and the second voltage V2 can be ground voltage GND. In another embodiment, the first voltage V1 can be a direct-current (DC) voltage, but the invention is not limited thereto. During display and touch sensing, the first voltage V1, the second voltage V2, and the data signal Sn are applied to the various elements of the touch display panel 110 to perform display and touch sensing operations.

[0055] During testing, a first voltage V1 and a second voltage V2 are applied to various components of the touch display panel 110 for damage detection. For example, the sensor pad 112 can be used as the component under test, and at least one source line 114 can be used as a reference component. The first voltage V1 is applied to the sensor pad 112, and the second voltage V2 is applied to the source line 114. Whether the sensor pad 112 is damaged can be determined from the feedback signal FB received by the sensor pad 112.

[0056] In another embodiment, at least one source line 114 can be used as the device under test, and the sensing pad 112 can be used as a reference element. A first voltage V1 is applied to the source line 114, and a second voltage V2 is applied to the sensing pad 112. Whether the source line 114 is damaged can be determined from the feedback signal FB received from the source line 114.

[0057] Figure 4 This is a schematic diagram illustrating a detection mechanism according to another embodiment of the present invention. (Refer to...) Figure 4 The touch display panel 110 also includes multiple gate lines 116 for display operation and multiple first switch circuits 122_3, and adds multiple second switch circuits 122_4 for damage detection. For clarity, Figure 4 Only one first switch circuit 122_3 and one second switch circuit 122_4 are shown, but the number of first switch circuits 122_3 and second switch circuits 122_4 is not intended to limit the invention.

[0058] During the detection, a first voltage V1 and a second voltage V2 are applied to the various components of the touch display panel 110 for damage detection. Whether the sensing pad 112 or at least one gate line 116 is damaged can be determined from the feedback signal FB received from the sensing pad 112 or at least one gate line 116.

[0059] Figure 5A This is a schematic diagram of a detection sensor pad according to an embodiment of the present invention. (Refer to...) Figure 5A The driver circuit 520 is used to detect whether the sensing pad itself is open-circuited.

[0060] The driver circuit 520 includes a switching circuit 522, an analog-front-end (AFE) circuit 524, and a processor circuit 526. Input signals are set for the sensing pad 512, the source line 514, and the gate line 516, respectively. For example, an LFD signal LFD is applied to the sensing pad 512, and the source line 514 is grounded. The gate line 516 is set to a high-impedance state HiZ. In an embodiment, the processor circuit 526 may include an analog-to-digital converter (ADC).

[0061] The AFE circuit 524 receives the feedback signal FB from the sensing pad 512 via the switching circuit 522 and outputs the feedback signal FB to the processor circuit 526 for data processing. The feedback signal FB includes voltage or capacitance information of the sensing pad 512. The driver circuit 520 can determine whether the sensing pad 512 is damaged based on the feedback signal FB.

[0062] Regarding the hardware structure of the driver circuit 520, the processor circuit 526 can be a processor with computing capabilities. Sufficient teaching, suggestions and implementation instructions on the hardware structure of the switch circuit 522, AFE circuit 524 and processor circuit 526 can be obtained by referring to common knowledge in related technologies, and will not be repeated here.

[0063] exist Figure 5A In this invention, the LFD signal is a sine wave, but the invention is not limited thereto. Figure 5B These are different waveforms of the LFD signal shown according to embodiments of the present invention. (Refer to...) Figure 5B , Figure 5B (a) shows that the LFD signal is a sine wave. Figure 5B Images (b) and (c) show that the LFD signal is a square wave and a triangular wave, respectively. Furthermore, the LFD signal can be a negative voltage. For example, Figure 5B (d), (e), and (f) show that the LFD signal is a negative sine wave, a negative square wave, and a negative triangular wave, respectively. Figure 5B The waveforms described herein are not intended to limit the invention.

[0064] Figure 6 This is a schematic diagram of a detection sensor pad according to another embodiment of the present invention. (Refer to...) Figure 6 The driver circuit 520 is used to detect whether the sensing pad is short-circuited with an adjacent sensing pad, source line, or gate line. In this embodiment, a DC signal is applied to the sensing pad 512, and the source line 514 and gate line 516 are grounded.

[0065] Figure 7 This is a schematic diagram of the detection source line according to an embodiment of the present invention. (Refer to...) Figure 7 The driver circuit 520 is used to detect whether the source line itself is open. In this embodiment, the LFD signal LFD is applied to the source line under test 514, and the sensing pad 512, adjacent source lines and gate lines 516 are grounded.

[0066] Figure 8 This is a schematic diagram of a detection source line according to another embodiment of the present invention. (Refer to...) Figure 8 The driver circuit 520 is used to detect whether the source line is short-circuited with an adjacent sensing pad, source line, or gate line. In this embodiment, a DC signal is applied to the source line under test 514, and the sensing pad 512, adjacent source lines, and gate lines 516 are also grounded.

[0067] Figure 9 and Figure 10 These are schematic diagrams illustrating the detection gate lines according to different embodiments of the present invention. (Refer to...) Figure 9 and Figure 10 ,exist Figure 9 In the middle, the driver circuit 520 is used to detect whether the gate line itself is open, while Figure 10 In this circuit, driver circuit 520 is used to detect whether the gate line is short-circuited to an adjacent sensing pad, source line, or gate line. An LFD signal LFD is applied to the gate line under test 516 for open-circuit detection, and a DC signal DC is applied to the gate line 516 for short-circuit detection. In both cases, sensing pad 512, source line 514, and adjacent gate lines are grounded.

[0068] Figure 11 This is a schematic diagram of a detection source line according to another embodiment of the present invention. Figure 12This is a flowchart illustrating the steps of a method for detecting damage to a touch display panel according to an embodiment of the present invention. (Refer to...) Figure 11 and Figure 12 The touch display panel 1110 includes multiple sensing pads 1112 and multiple signal lines, wherein the signal lines are the source lines S0, S1, S2, S3 and the gate lines G0, G1, G2 of the touch display panel 1110.

[0069] In step S100, during the detection period, the driver circuit 1120 selects at least one first element from the sensing pad 1112 and signal lines S0, S1, S2, S3 and G0, G1, G2 as the element under test, and selects at least one second element from the sensing pad 1112 and signal lines S0, S1, S2, S3 and G0, G1, G2 as the reference element. Figure 11 In this configuration, source line S0 is selected as the device under test (DUT), and sensing pad 1112, source lines S1, S2, S3, and gate lines G0, G1, G2 are selected as reference elements. Reference elements 1112, S1, S2, S3, and G0, G1, G2 are adjacent to the DUT S0.

[0070] In step S110, the driver circuit 1120 applies a first voltage V1 to the device under test S0 and a second voltage V2 to the reference elements 1112, S1, S2, S3, and G0, G1, G2. In an embodiment, the first voltage V1 may be an LFD signal or a DC voltage, and the second voltage V2 may be a ground voltage. In an embodiment, the driver circuit 1120 may place the reference elements 1112, S1, S2, S3, and G0, G1, G2 in a floating state or a high-impedance state.

[0071] In step S120, the driver circuit 1120 receives a feedback signal FB from the device under test (DUT) S0, wherein the feedback signal FB includes voltage or capacitance information of the DUT S0. For example, the capacitance information includes the capacitance values ​​Cs1, Cs2, ..., CsN between the DUT S0 and the reference elements 1112, S1, S2, S3 and G0, G1, G2, etc. Figure 11 As shown. The component under test S0 and the reference components 1112, S1, S2, S3 and G0, G1, G2 have a first capacitance value Cs = Cs1 + Cs2 + ... + Cs7 + ... + CsN under normal conditions, where N is a positive integer.

[0072] On the other hand, the device under test (DUT) S0 is connected to an AFE circuit 1124 with operational amplifier virtual short-circuit characteristics, thus allowing DUT S0 to maintain a first voltage V1. Furthermore, the input signals to reference elements 1112, S1, S2, S3, and G0, G1, G2 are a second voltage V2. Therefore, the voltage information includes the first voltage difference ΔV between DUT S0 and reference elements 1112, S1, S2, S3, and G0, G1, G2 under normal conditions, where ΔV = V1 - V2.

[0073] In this embodiment, the driver circuit 1120 switches the switching circuit 1122 to apply a first voltage V1 to the device under test S0, and a second voltage V2 to the reference elements 1112, S1, S2, S3 and G0, G1, G2, or to receive a feedback signal FB from the device under test S0. For a detailed description of the switching operation of the switching circuit 1122, please refer to... Figures 2 to 4 Examples of implementations.

[0074] In step S130, the driver circuit 1120 determines whether the component under test (DUT) S0 is damaged based on the feedback signal FB. Damage to the DUT S0 means that the DUT S0 is open-circuited or short-circuited with adjacent sensing pads 1112 or adjacent signal lines S1, S2, S3 and G0, G1, G2. The driver circuit 1120 can analyze the capacitance and voltage information of the DUT S0 through the processor circuit 1126 and / or other back-end circuits to obtain the detection result.

[0075] Figure 13 This is a schematic diagram illustrating an open circuit of the component under test according to an embodiment of the present invention. (See reference) Figure 11 and Figure 13 The device under test (DUT) S0 is in an abnormal state, such as being open-circuited. In the open-circuit state, the DUT S0 and the reference elements 1112, S1, S2, S3 and G0, G1, G2 have a second capacitance value Cs', where the first capacitance value Cs is greater than the second capacitance value Cs' because the first voltage V1 is only applied to the open portion of the DUT S0.

[0076] For example, the first capacitance value Cs in the normal state and the second capacitance value Cs' in the abnormal state can be listed below.

[0077] In Table 1:

[0078] Open circuit test Capacitance (picofarads) Normal state Cs = 180pF Abnormal state Cs' = 50pF

[0079] Table 1

[0080] Figure 11 The device under test (S0) is shown in its normal state. Figure 13The device under test (DUT) S0 is shown in an abnormal state (open circuit state). The driver circuit 1120 can obtain capacitance information by receiving the feedback signal FB, and determine whether the DUT S0 is open-circuited based on the capacitance information and Table 1. The values ​​listed in Table 1 are not intended to limit the invention.

[0081] Similarly, the driver circuit 1120 can determine whether the sensing pad or the gate line is open-circuited based on the capacitance information.

[0082] Figure 14 This is a schematic diagram illustrating a short circuit between the device under test and an adjacent source line, according to an embodiment of the present invention. (See reference) Figure 11 and Figure 14 The device under test (DUT) S0 is in an abnormal state, for example, short-circuited with the adjacent source line S1. In the short-circuit state, there is a second voltage difference ΔV' between the DUT S0 and the source line S1, where the first voltage difference ΔV is greater than the second voltage difference ΔV' because the DUT S0 is short-circuited with the source line S1.

[0083] For example, when the device under test S0 is short-circuited with the source line S1, the second voltage difference ΔV' may be 1 volt (V). The first voltage difference ΔV under normal conditions and the second voltage difference ΔV' under abnormal conditions can be listed in Table 2 below:

[0084] Short circuit test Voltage difference (voltage) Normal state △V=2.75V Abnormal state △V'=1V

[0085] Table 2

[0086] Figure 11 The device under test (S0) is shown in its normal state. Figure 14 The device under test (DUT) S0 is displayed in an abnormal state (short circuit state). The driver circuit 1120 can obtain voltage information by receiving the feedback signal FB, and determine whether the DUT S0 is short-circuited with the source line S1 based on the voltage information and Table 2. The values ​​listed in Table 2 are not intended to limit the invention.

[0087] Similarly, the driver circuit 1120 can determine whether the device under test S0 is short-circuited with the adjacent sensing pad or the adjacent gate line based on the voltage information.

[0088] exist Figure 11 In this invention, only one source line S0 is selected as the device under test, but the invention is not limited thereto. Figure 15 This is a schematic diagram illustrating the simultaneous detection of multiple source lines according to an embodiment of the present invention. (Reference) Figure 15 Taking open-circuit testing as an example, source lines S0, S4, and S8 can be selected to be tested simultaneously. In this case, the driver circuit 1120' includes multiple switching circuits, multiple AFE circuits, and multiple processor circuits for testing multiple devices under test. In another embodiment, the multiple processor circuits can be integrated into a single circuit.

[0089] Figure 16 This is a schematic diagram illustrating the sequential detection of multiple source lines according to an embodiment of the present invention. (See reference) Figure 16 The source lines S0, S1, S2, and S3 are detected in sequence. Figure 17 This is a schematic diagram illustrating the sequential detection of multiple gate lines according to an embodiment of the present invention. (See reference) Figure 17 Gate lines G0, G1, and G2 are detected in sequence. Figure 18 This is a schematic diagram illustrating the sequential detection of multiple sensor pads according to an embodiment of the present invention. (See reference) Figure 18 The sensor pads 1112_1, 1112_2, and 1112_3 were detected in sequence.

[0090] exist Figures 16 to 18 During the detection process, a first voltage V1 is sequentially applied to the device under test (DUT), and a second voltage V2 is applied to the reference element.

[0091] In summary, in the embodiments of the present invention, during detection, the driver circuit applies a first voltage to the device under test (DUT) and applies a second voltage to a reference element, or places the reference element in a floating state or a high-impedance state, to obtain voltage or capacitance information of the DUT. The driver circuit can detect component abnormalities in the touch display panel based on the voltage or capacitance information of the DUT.

[0092] Those skilled in the art will be able to make various modifications and variations to the disclosed embodiments without departing from the scope or spirit of this disclosure. In view of the foregoing, it is intended that this disclosure cover modifications and variations, provided that such modifications and variations fall within the scope of the following claims and their equivalents.

Claims

1. A method for detecting damage to a touch display panel, wherein the touch display panel includes a plurality of sensor pads and a plurality of signal lines, the method comprising: At least one first element is selected from the sensing pad and the signal line as the element to be tested; A first voltage is applied to the device under test and a feedback signal is received from the device under test, wherein the feedback signal includes voltage information or capacitance information of the device under test; as well as The test component is determined to be damaged based on the feedback signal.

2. The method for detecting damage to a touch display panel according to claim 1, wherein the damage to the component under test indicates that the component under test is open-circuited or short-circuited with an adjacent sensing pad or an adjacent signal line.

3. The method for detecting damage to a touch display panel according to claim 2, wherein the step of determining whether the component under test is damaged based on the feedback signal includes: Based on the capacitance information, determine whether the component under test is open-circuited.

4. The method for detecting damage to a touch display panel according to claim 3, wherein the capacitance information includes the capacitance value between the element under test and a reference element, and the reference element is selected from an adjacent sensing pad or an adjacent signal line.

5. The method for detecting damage to a touch display panel according to claim 4, wherein the capacitance value is a first capacitance value under normal conditions and a second capacitance value under abnormal conditions, and the first capacitance value is greater than the second capacitance value.

6. The method for detecting damage to a touch display panel according to claim 2, wherein the step of determining whether the component under test is damaged based on the feedback signal includes: Based on the voltage information, determine whether the device under test is short-circuited with an adjacent sensing pad or an adjacent signal line.

7. The method for detecting damage to a touch display panel according to claim 6, wherein the voltage information includes the voltage difference between the element under test and a reference element, and the reference element is selected from an adjacent sensing pad or an adjacent signal line.

8. The method for detecting damage to a touch display panel according to claim 7, wherein the voltage difference is a first voltage difference under normal conditions and a second voltage difference under abnormal conditions, and the first voltage difference is greater than the second voltage difference.

9. The method for detecting damage to a touch display panel according to claim 1 further includes: At least one second element is selected from the sensing pad and the signal line as a reference element, wherein the capacitance information includes the capacitance value between the element under test and the reference element, and the voltage information includes the voltage difference between the element under test and the reference element.

10. The method for detecting damage to a touch display panel according to claim 9, wherein the reference element is adjacent to the element under test.

11. The method for detecting damage to a touch display panel according to claim 9 further includes: A second voltage is applied to the reference element.

12. The method for detecting damage to a touch display panel according to claim 9 further includes: The reference element is placed in a floating state or a high impedance state.

13. The method for detecting damage to a touch display panel according to claim 1, wherein the signal line is a source line or a gate line of the touch display panel.

14. The method for detecting damage to a touch display panel according to claim 1 further includes: The switching circuit is used to apply the first voltage to the device under test or to receive the feedback signal from the device under test.

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