Electronic device and method for driving touch display panel

Abstract

The invention provides an electronic device and a method for driving a touch display panel. The electronic device is configured to detect a touch event of a stylus and a hand. The electronic device comprises a touch display panel and a driving circuit. The touch display panel is configured to detect a touch event of a stylus and a hand. The touch display panel comprises a plurality of driving lines. The driving circuit is coupled to the touch display panel. The drive circuit is configured to determine a first region and a second region. The stylus touches the first area, and the hand touches the second area. When the touch display panel detects a touch event of the stylus and the hand, the driving circuit is configured to cause the driving lines corresponding to the second area to be in a high impedance state.

Description

Technical Field

[0001] The present invention relates to an electronic device and a method for driving a touch display panel. Background Art

[0002] In recent years, it has become increasingly common to use a stylus to operate smartphones and tablet computers. Styluses can provide more precise clicks, smoother movements, and can be used to draw more complex drawings, thereby expanding their business opportunities. For comfort and stability, when using a stylus, users often not only hold the stylus, but also place their hand on the touch panel of the mobile device. However, if the mobile device is placed on a table, the stylus with a relatively small capacitance value will have a low signal-to-noise ratio (SNR), so the stylus may not be able to click or slide. This will make it difficult to distinguish the stylus from the touch of the hand or other interference, increase the challenge of detection, and result in a poor user experience. Summary of the Invention

[0003] The present invention provides an electronic device and a method for driving a touch display panel, which can effectively distinguish between touches of a stylus pen and hands or other interferences, so as to provide a good user experience.

[0004] An embodiment of the present invention provides an electronic device configured to detect touch events from a stylus pen and a hand. The electronic device includes a touch display panel and a drive circuit. The touch display panel is configured to detect touch events from a stylus pen and a hand. The touch display panel includes a plurality of drive lines. The drive circuit is coupled to the touch display panel. The drive circuit is configured to determine whether a first area and a second area are present. When a stylus pen touches the first area and a hand touches the second area, the drive circuit is configured to place the drive line corresponding to the second area in a high impedance state when the touch display panel detects the touch events from the stylus pen and the hand.

[0005] Embodiments of the present invention provide a method for driving a touch display panel. The touch display panel has multiple drive lines. The method includes detecting a touch event by a stylus pen or a hand; determining a first area and a second area, wherein the stylus pen touches the first area and the hand touches the second area; and, when the touch display panel detects the touch event by the stylus pen or the hand, driving the drive line corresponding to the second area into a high impedance state.

[0006] In order to make the foregoing content more comprehensible, several embodiments are described in detail below with accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 FIG. 1 is a schematic diagram of an electronic device according to an embodiment of the present invention.

[0008] Figure 2FIG. 1 is a block diagram of an electronic device according to an embodiment of the present invention.

[0009] Figure 3 FIG. 1 is a schematic diagram illustrating an application scenario of an electronic device according to an embodiment of the present invention.

[0010] Figure 4A and Figure 4B Schematic diagrams of sensing units of a touch display panel and their signal values according to different embodiments of the present invention.

[0011] Figure 5 FIG. 4 is a structural diagram of a touch display panel according to an embodiment of the present invention.

[0012] Figure 6 To show Figure 5 Schematic diagram of a touch display panel including a sensing unit.

[0013] Figure 7 The flowchart shows the steps of a method for driving a touch display panel according to an embodiment of the present invention.

[0014] Figure 8 The figure is a flowchart showing a method for driving a touch display panel according to another embodiment of the present invention.

[0015] Figure 9 FIG. 1 is a waveform diagram of a touch sensing signal, a common signal, and sensing data according to an embodiment of the present invention.

[0016] Explanation of Figure Numbers

[0017] 100: electronic device;

[0018] 110: driving circuit;

[0019] 120, 520: touch display panel;

[0020] 122, 622: touch sensing unit;

[0021] 310: stylus;

[0022] 320: Hand;

[0023] 410, 420: detection area;

[0024] 522: touch sensor;

[0025] 524: display pixels;

[0026] 610: First area;

[0027] 620: Second area;

[0028] 620_1: first sub-area;

[0029] 620_2: second sub-area;

[0030] 900: dotted frame;

[0031] D1, D2: scanning direction;

[0032] GDL: Display scan lines;

[0033] S100, S110, S120, S200, S210, S220, S230, S240, S250, S260, S270, S280, S290, S300: steps;

[0034] SDL: display data line;

[0035] TSHD: touch sensing signal;

[0036] TSL: driver line;

[0037] VCOM: common signal;

[0038] X1~X10: columns;

[0039] Y1~Y30: OK. DETAILED DESCRIPTION

[0040] The following embodiments are provided to describe the present disclosure in detail, but the present disclosure is not limited to the provided embodiments, and the provided embodiments can be appropriately combined. The terms "coupling / coupled" or "connecting / connected" used in this specification (including claims) of this application may refer to any direct or indirect connection method. For example, "a first device is coupled to a 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." In addition, the term "signal" may refer to current, voltage, charge, temperature, data, electromagnetic waves, or any one or more signals.

[0041] Figure 1 FIG. 1 is a schematic diagram of an electronic device according to an embodiment of the present invention. Figure 2 FIG is a block diagram of an electronic device according to an embodiment of the present invention. Figure 1 and Figure 2 , the electronic device 100 includes a driving circuit 110 and a touch display panel 120. The driving circuit 110 is configured to be coupled to the touch display panel 120. The electronic circuit 110 is suitable for driving the touch display panel 120.

[0042] In this embodiment, the electronic device 100 may be an electronic device with a display function, a touch sensing function, and / or a fingerprint sensing function. In an embodiment, the electronic device 100 may be, but is not limited to, a smartphone, a non-smartphone, a wearable electronic device, a tablet computer, a personal digital assistant, a notebook, and other portable electronic devices that can operate independently and have a display function, a touch sensing function, and / or a fingerprint sensing function. In an embodiment, the electronic device 100 may be, but is not limited to, a portable or non-portable electronic device in a vehicle intelligent system. In an embodiment, the electronic device 100 may be, but is not limited to, a smart home appliance, such as a television, a computer, a refrigerator, a washing machine, a telephone, an induction cooker, a table lamp, and the like.

[0043] In an embodiment, when the electronic circuit 110 is implemented as a single-chip integrated circuit that can drive and control the touch display panel 120 to perform display operations, touch sensing operations and / or fingerprint sensing operations, the electronic circuit 110 may include a control circuit, and the control circuit may be a microcontroller-based core to perform all control activities of the display operation, touch sensing operation and / or fingerprint sensing operation.

[0044] about Figure 2 In the embodiment of the present invention, the drive circuit 110 may include a processor with computing capabilities. Alternatively, the drive circuit 110 may be designed using hardware description languages (HDL) or any other digital circuit design method familiar to those skilled in the art, and may be a hardware circuit implemented using a field programmable gate array (FPGA), a complex programmable logic device (CPLD), or an application-specific integrated circuit (ASIC). In addition, reference may be made to common knowledge in the relevant art to obtain sufficient teachings, suggestions, and implementation instructions for the hardware structure of the drive circuit 110 and the touch display panel 120.

[0045] Figure 3 FIG is a schematic diagram of an application scenario of an electronic device according to an embodiment of the present invention. Figures 1 to 3 Taking a portable electronic device as an example, the electronic device 100 is configured to detect touch events from a stylus 310 and a user's hand 320. The driving circuit 110 is configured to drive the touch display panel 120 to detect touch events from the stylus 310 and the user's hand 320. The touch display panel 120 may include an active area and a peripheral area, and the active area is configured as a detection area for detecting touch events. Figure 3 The application scenarios are only used for illustration and are not intended to limit the present invention.

[0046] In this embodiment, compared with the hand, the passive capacitive stylus or gloves have a relatively small signal value. Specifically, Figure 4A and Figure 4B Schematic diagram of a sensing unit of a touch display panel and its signal value according to different embodiments of the present invention. Figures 3 to 4B The touch display panel 120 includes a plurality of touch sensing units 122. The touch sensing units 122 are arranged in an array, including a plurality of columns X1 to X10 and a plurality of rows Y1 to Y30. The signal values in the figure are the capacitance values of the touch sensing units 122.

[0047] In this embodiment, the driver circuit 110 can drive the touch display panel 120 to perform a scanning operation to detect touch events. For example, the touch display panel 120 can perform a scanning operation in the horizontal direction, with columns X1 to X10 of the touch sensing units 122 being scanned from both sides to the center, as shown by scanning directions D1 and D2. Scanning directions D1 and D2 are for illustration only and do not limit the present invention. In addition, the signal values and number of touch sensing units 122, the number of columns X1 to X10, and the number of rows Y1 to Y30 are for illustration only and do not limit the present invention.

[0048] Figure 4A FIG. 1 shows an embodiment in which the stylus pen 310 touches the touch display panel 120. Figure 4A In FIG. 4 , the stylus pen 310 touches the detection area 410 , and compared with other detection areas, the detection area 410 has a relatively large signal value. Figure 4B FIG. 1 shows an embodiment in which a hand 320 touches the touch display panel 120. Figure 4B In FIG. 4 , the hand 320 touches the detection area 420 , and compared with other detection areas, the detection area 420 has a relatively large signal value.

[0049] Depend on Figure 4A and Figure 4B As can be seen, detection area 410 of stylus 310 has a relatively smaller signal value than detection area 420 of hand 320. Therefore, when touch display panel 120 detects touch events of stylus 310 and hand 320, the signal value of hand 320 may affect the signal value of stylus 310.

[0050] In order to reduce the influence of hands or other interference, in an embodiment of the present invention, when the touch display panel 120 detects touch events of the stylus 310 and the hand 320, the driving circuit 110 is configured to put the driving lines of other detection areas except the detection area 410 into a high impedance state.

[0051] Figure 5 FIG is a structural diagram of a touch display panel according to an embodiment of the present invention. Figure 5 The touch display panel 520 includes a plurality of touch sensors 522 and a plurality of display pixels 524. The sensing unit includes the plurality of touch sensors 522. In an embodiment, each touch sensor can be formed by connecting a plurality of common electrodes, which have a common display voltage during the display phase. Alternatively, the touch sensors 522 can function as common electrodes during the display phase.

[0052] Specifically, the driver circuit 110 drives the display pixels 524 via the display scan lines GDL and the display data lines SDL to display an image. Each display pixel 524 is a pixel, not a sub-pixel, representing the basic unit of display resolution. For example, each display pixel 524 is a full-color pixel comprising R, G, and B sub-pixels. Each display data line SDL is a data line group comprising multiple data lines corresponding to a display pixel.

[0053] The driver circuit 110 can also be used to drive and control the touch sensor 522 via the drive line TSL to sense touch events. For self-capacitive touch sensing, touch drive signals and touch sensing signals can be transmitted on the drive line TSL. For mutual capacitance touch sensing, the touch display panel 520 may also include sensing lines for transmitting touch sensing signals. In an embodiment, the touch display panel 520 may be an in-cell touch display panel with the touch sensor embedded therein, but the present invention is not limited thereto.

[0054] In this embodiment, the driving line TSL may be connected to a corresponding switch (not shown), and the driving circuit 110 may turn off the corresponding switch to put the driving line in the second region into a high impedance state.

[0055] For example, Figure 6 Show Figure 5 Schematic diagram of a touch display panel, the touch display panel includes a sensing unit. Figures 5 and 6, the touch display panel 520 includes a plurality of sensing units 622, and the sensing unit 622 includes a plurality of touch sensors 522. At least one of the touch sensing units 622 forms a detection area. The touch display panel 520 includes a plurality of driving lines. The stylus 310 touches the first area 610, and the hand 320 touches the second area 620. The second area 620 is all the detection areas on the touch display panel 520 except the first area 610. The second area 620 is larger than the first area 610. The driving circuit 110 can determine the first area 610 and the second area 620, and disconnect the switch connected to the driving line corresponding to the second area. When the touch display panel 520 detects the touch events of the stylus 310 and the hand 320, the driving line corresponding to the second area can be put into a high impedance state. The driving line corresponding to the second area can be Figure 5 Therefore, the driving circuit 110 can put the driving lines corresponding to the second area into a high impedance state and scan only the first area 610 of the touch display panel 520 during the touch period.

[0056] Furthermore, the second area 620 includes a first sub-area 620_1 and a second sub-area 620_2. The hand 320 touches the first sub-area 620_1, and the second sub-area 620_2 is the entire detection area on the touch display panel 520, excluding the first area 610 and the first sub-area 620_1. The first sub-area 620_1 is smaller than the second sub-area 620_2. When the touch display panel 120 detects touch events from the stylus 310 and the hand 320, the drive circuit 110 places the drive lines corresponding to the first sub-area 620_1 and the second sub-area 620_2 in a high-impedance state.

[0057] Figure 7 FIG1 is a flowchart showing a method for driving a touch display panel according to an embodiment of the present invention. Figures 1 to 3 、 Figure 6 as well as Figure 7 In this embodiment, the method for sensing a touch event is at least suitable for Figure 1 The electronic device 100 is shown, but the present disclosure is not limited thereto.

[0058] In step S100, using the electronic device 100 as an example, the driver circuit 110 drives the touch display panel 520 to detect touch events from the stylus 310 and the hand 320. In step S110, the driver circuit 110 determines whether the detection area is the first area 610 or the second area 620. The stylus 310 touches the first area 610, and the hand 320 touches the second area 620. The second area 620 is the entire detection area on the touch display panel 520 except the first area 610. In an embodiment, the driver circuit 110 determines whether the detection area is the first area 610 or the second area 620 based on at least one of the unit signal value, total signal value, signal peak value, and area size of at least one touch sensing unit 622.

[0059] In step S120, when the touch display panel 520 detects a touch event by the stylus 310 and the hand 320, the driving circuit 110 places the driving line corresponding to the second area 620 in a high impedance state. Therefore, the driving circuit 110 can scan only the first area 610 of the touch display panel 520 during a touch event to reduce the influence of the hand or other interference.

[0060] The method for driving the touch display panel in this embodiment can be as follows: Figures 1 to 6 The embodiments of the present invention are fully taught, suggested and implemented, and therefore no further details are given.

[0061] Figure 8 FIG1 is a flowchart showing a method for driving a touch display panel according to another embodiment of the present invention. Figures 1 to 3 、 Figure 6 and Figure 8 In this embodiment, the method for detecting the stylus is at least suitable for Figure 1 The electronic device 100 is shown, but the present disclosure is not limited thereto.

[0062] In step S200, the driver circuit 110 determines whether the touch display panel 520 is to be operated in a stylus detection mode. If the touch display panel 520 is to be operated in a stylus detection mode, the driver circuit 110 performs step S210. In step S210, the driver circuit 110 finds the pen area (first area) 610 from the minimum area.

[0063] Next, in step S220, the driving circuit 110 determines the size of the pen area 610 based on the unit signal value of the touch sensing unit, and whether the size determined by the pen area 610 is less than the reference pitch value. The unit signal value indicates the capacitance value of the touch sensing unit to be determined. If the size determined by the pen area 610 is less than the reference pitch value (for example, three pitches, but the present invention is not limited to this), the driving circuit 110 determines that the area to be determined is the pen area 610 and executes step S230. If the size determined by the pen area 610 is greater than or equal to the reference pitch value, the driving circuit 110 determines that the area to be determined is not the pen area 610 and executes step S250. In step S250, the driving circuit 110 drives the touch display panel 520 to operate in a mode for detecting a hand. In the mode for detecting a hand, the driving circuit 110 scans all detection areas of the touch display panel 520.

[0064] In step S230, the driver circuit 110 determines whether the peak signal value (i.e., the maximum signal value) of the touch sensing unit in the pen area 610 is less than a first reference capacitance value. If the peak signal value of the touch sensing unit in the pen area 610 is less than the first reference capacitance value (e.g., 180 pF, but the present invention is not limited thereto), the driver circuit 110 determines that the area to be determined is the pen area 610 and executes step S240. If the peak signal value of the touch sensing unit in the pen area 610 is greater than or equal to the first reference capacitance value, the driver circuit 110 determines that the area to be determined is not the pen area 610 and executes step S250.

[0065] In step S240, the driving circuit 110 determines whether the total signal value (i.e., the sum of the signal values) of the touch sensing units of the pen area 610 is less than the second reference capacitance value. If the total signal value of the touch sensing units of the pen area 610 is less than the second reference capacitance value (e.g., 300 pF, but the present invention is not limited thereto), the driving circuit 110 determines that the area to be determined is the pen area 610 and executes step S260. In step S260, the driving circuit 110 drives the touch display panel 520 to operate in a mode for detecting a stylus. In the mode for detecting a stylus, the driving circuit 110 scans only the pen area 610 and puts the driving lines corresponding to the area 620 other than the pen area 610 into a high impedance state. If the total signal value of the touch sensing units of the pen area 610 is greater than or equal to the second reference capacitance value, the driving circuit 110 determines that the area to be determined is not the pen area 610 and executes step S250.

[0066] In steps S220, S230, and S240, the driver circuit 110 determines whether the detection area is the pen area 610 based on the unit signal value, total signal value, signal peak value, and area size of the touch sensing unit. However, the present invention is not limited to this. In an embodiment, the driver circuit may determine whether the detection area is the pen area based on the unit signal value, total signal value, signal peak value, and area size of at least one touch sensing unit.

[0067] After step S220, step S230, and step S240, the driving circuit 110 may locate the pen region 610. In one embodiment, the driving circuit 110 may repeat step S220, step S230, and step S240 multiple times to ensure that the position of the pen region 610 is correct.

[0068] On the other hand, if the touch display panel 520 is not operating in the mode for detecting the stylus pen, the driving circuit 110 performs step S270. In step S270, the driving circuit 110 finds the hand area (second area) from the largest area.

[0069] In step S280, the driver circuit 110 determines whether the total signal value (i.e., the sum of the signal values) of the touch sensing units of the hand region 620_1 is greater than a third reference capacitance value. If the total signal value of the touch sensing units of the hand region 620_1 is greater than the third reference capacitance value (e.g., 2000 pF, but the present invention is not limited thereto), the driver circuit 110 determines that the area to be determined is the hand region 620_1 and locates the hand region 620_1 in step S290. If the total signal value of the touch sensing units of the hand region 620_1 is less than or equal to the third reference capacitance value, the driver circuit 110 determines that the area to be determined is not the hand region 620_1 and executes step S250.

[0070] In step S300 , the driving circuit 110 puts the driving line corresponding to the hand region 620_1 (the first sub-region) into a high impedance state to facilitate positioning of the pen region 610 . After step S300 , the driving circuit 110 may return to step S210 to further position the pen region 610 .

[0071] In step S280, the driver circuit 110 determines whether the detection area is the hand area 620_1 based on the total signal value of the touch sensing unit, but the present invention is not limited thereto. In an embodiment, the driver circuit may determine whether the detection area is the hand area based on at least one of the unit signal value, total signal value, signal peak value, and area size of at least one touch sensing unit.

[0072] The method for driving the touch display panel in this embodiment can be as follows: Figures 1 to 7 The embodiments of the present invention are fully taught, suggested and implemented, and therefore no further details are given.

[0073] Figure 9 FIG1 is a waveform diagram of a touch sensing signal, a common signal and sensing data according to an embodiment of the present invention. Figure 9 The high-level period of touch sensing signal TSHD indicates a touch period. Common signal VCOM indicates that sensing data from stylus pen 310 has been accumulated multiple times. The dashed box 900 indicates that sensing data from stylus pen 310 has been accumulated once. That is, because driver circuit 110 scans only the pen area 610 of touch display panel 520 during a touch period, driver circuit 110 can increase the signal accumulation time for stylus pen 310 during a touch period.

[0074] In summary, in an embodiment of the present invention, the driving circuit can locate the stylus based on the unit signal value, total signal value, signal peak value and / or area size of the touch sensing unit. For the pen area, the driving circuit enhances the signal-to-noise ratio of the stylus by increasing the signal accumulation time during the touch to minimize the influence of noise. For areas other than the pen area, when the touch display panel detects touch events of the stylus and the hand to reduce the influence of the hand or other interference, the driving circuit puts the driving line of the area other than the pen area into a high impedance state. Therefore, the electronic device and the method for driving the touch display panel can effectively distinguish between the touch of the stylus and the hand or other interference to provide a good user experience.

[0075] It is for those skilled in the art that various modifications and variations may be made to the disclosed embodiments without departing from the scope or spirit of the present disclosure. In view of the foregoing, it is intended that the present disclosure covers modifications and variations, provided that the modifications and variations fall within the scope of the following claims and their equivalents.

Claims

1. An electronic device configured to detect touch events of a stylus pen and a hand, the electronic device comprising: a touch display panel configured to detect the touch events of the stylus and the hand, wherein the touch display panel comprises a plurality of driving lines; as well as A driving circuit is coupled to the touch display panel and configured to determine a first area and a second area, wherein the stylus touches the first area and the hand touches the second area, and when the touch display panel detects the touch events of the stylus and the hand, the driving circuit is configured to put the driving line corresponding to the second area into a high impedance state. 2 . The electronic device according to claim 1 , wherein the second area is all detection areas on the touch display panel except the first area. The electronic device according to claim 1 , wherein the second area is larger than the first area.

4. The electronic device according to claim 1, wherein the touch display panel includes a plurality of touch sensing units, at least one of the touch sensing units forms a detection area, and the driving circuit determines whether the detection area is the first area based on the unit signal value, total signal value, signal peak value and area size of the at least one touch sensing unit. The electronic device according to claim 1 , wherein the driving circuit scans only the first area of the touch display panel during a touch period. The electronic device according to claim 5 , wherein the driving circuit increases a signal accumulation time of the stylus during the touch period.

7. The electronic device according to claim 1, wherein the second area includes a first sub-area and a second sub-area, the hand touches the first sub-area, and when the touch display panel detects the touch event of the stylus and the hand, the driving circuit puts the driving line corresponding to the first sub-area into the high impedance state. 8 . The electronic device according to claim 7 , wherein when the touch display panel detects the touch event of the stylus pen and the hand, the driving circuit further enables the driving line corresponding to the second sub-area to be in the high impedance state. The electronic device according to claim 7 , wherein the first sub-area is smaller than the second sub-area.

10. The electronic device according to claim 7, wherein the touch display panel comprises a plurality of touch sensing units, at least one of the touch sensing units forms a detection area, and the driving circuit determines whether the detection area is the first sub-area based on at least one of the unit signal value, total signal value, signal peak value and area size of the at least one touch sensing unit.

11. A method for driving a touch display panel, wherein the touch display panel has a plurality of drive lines, the method comprising: Detect touch events from stylus and hand; determining a first area and a second area, wherein the stylus touches the first area and the hand touches the second area; as well as When the touch display panel detects the touch event of the stylus pen and the hand, the driving line corresponding to the second area is placed in a high impedance state. 12 . The method for driving a touch display panel according to claim 11 , wherein the second area is all detection areas on the touch display panel except the first area. 13 . The method for driving a touch display panel according to claim 11 , wherein the second area is larger than the first area.

14. The method for driving a touch display panel according to claim 11 , wherein the touch display panel comprises a plurality of touch sensing units, at least one of the touch sensing units forms a detection area, and the step of determining the first area and the second area comprises: Whether the detection area is the first area is determined according to at least one of a unit signal value, a total signal value, a signal peak value, and an area size of the at least one touch sensing unit.

15. The method for driving a touch display panel according to claim 11, further comprising: Only the first area of the touch display panel is scanned during a touch period.

16. The method for driving a touch display panel according to claim 15, further comprising: The signal accumulation time of the stylus is increased during the touch period.

17. The method for driving a touch display panel according to claim 11 , wherein the second area includes a first sub-area and a second sub-area, the hand touches the first sub-area, and when the touch display panel detects the touch event of the stylus and the hand, the step of placing the driving line corresponding to the second area in the high-impedance state comprises: When the touch display panel detects the touch event of the stylus pen and the hand, the driving line corresponding to the first sub-area is placed in the high impedance state.

18. The method for driving a touch display panel according to claim 17 , wherein when the touch display panel detects the touch event of the stylus pen and the hand, the step of placing the driving line corresponding to the second area in the high impedance state further comprises: When the touch display panel detects the touch event of the stylus pen and the hand, the driving line corresponding to the second sub-area is placed in the high impedance state. 19 . The method for driving a touch display panel according to claim 17 , wherein the first sub-area is smaller than the second sub-area.

20. The method for driving a touch display panel according to claim 17 , wherein the touch display panel comprises a plurality of touch sensing units, at least one of the touch sensing units forms a detection area, and the step of determining the first area and the second area comprises: Whether the detection area is the first sub-area is determined according to at least one of a unit signal value, a total signal value, a signal peak value, and an area size of the at least one touch sensing unit.

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