Touch display device and touch driving method

Abstract

A touch display device and a touch driving method thereof are provided. The touch driving method includes: setting a first and a second touch signals; during a touch sensing phase, obtaining first and second touch raw data corresponding to the touch area based on the first and the second touch signals; determining whether a touch has occurred based on the first and the second touch raw data; determining whether a first touch sensing amount is greater than a second touch sensing amount while a touch is detected; not performing for reporting a touch point of a touch sensing operation based on the touch area while the first touch sensing amount is greater than the second touch sensing amount; performing for reporting the touch point of the touch sensing operation based on the touch area while the first touch sensing amount is not greater than the second touch sensing amount .

Description

Technical Field

[0001] This invention relates to a control technology for a touch display device, and more particularly to a touch display device and a touch driving method. Prior Technology

[0002] Modern display devices often incorporate a touch layer to enhance touch functionality. On the other hand, the display panel in a display device is typically formed by a pixel array consisting of multiple data lines and scan lines. In some types of display panels, when a touch area in the touch layer is touched, the coupling capacitance between this touch area and a data line set to a floating state causes a corresponding change in capacitance value across all touch areas on that data line. This can easily lead to false alarms or misjudged touch areas in subsequent touch area detection. Solving or avoiding these problems in display devices is a research direction. Summary of the Invention

[0003] The present invention provides a touch display device and a touch driving method, which enables the touch display device to determine whether the touch sensing amount generated by each touch area is a change in capacitance value caused by the coupling capacitor, thereby avoiding false alarms.

[0004] The touch driving method of the touch display device of the present invention includes the following steps: setting a first touch signal having a first touch charging period and a second touch signal having a second touch charging period, wherein the first touch charging period is shorter than the second touch charging period; in a touch sensing stage, controlling a touch driving circuit coupled to a touch area based on the first touch signal and the second touch signal to obtain first touch raw data and second touch raw data corresponding to the touch area; calculating a first touch sensing quantity based on the first touch raw data, calculating a second touch sensing quantity based on the second touch raw data, and determining whether a touch has occurred based on the first touch sensing quantity or the second touch sensing quantity; when it is determined that a touch has occurred, determining whether the first touch sensing quantity is greater than the second touch sensing quantity; when the first touch sensing quantity is greater than the second touch sensing quantity, not reporting a touch sensing operation based on the corresponding touch area; and when the first touch sensing quantity is not greater than the second touch sensing quantity, reporting a touch sensing operation based on the corresponding touch area.

[0005] The touch display device of the present invention includes a touch panel, a touch driving circuit, and a controller. The display panel includes a touch layer. The touch layer includes multiple touch areas. The touch driving circuit is coupled to the touch areas to obtain raw touch data corresponding to the touch areas. The controller is coupled to the touch driving circuit to control the touch driving circuit to perform touch sensing operations. The controller is configured to: set a first touch signal having a first touch charging period and a second touch signal having a second touch charging period, wherein the first touch charging period is shorter than the second touch charging period; during the touch sensing phase, control a touch driving circuit coupled to a touch area based on the first touch signal and the second touch signal to obtain first touch raw data and second touch raw data corresponding to the touch area; calculate a first touch sensing quantity based on the first touch raw data, calculate a second touch sensing quantity based on the second touch raw data, and determine whether a touch has occurred based on the first touch sensing quantity or the second touch sensing quantity; when a touch has occurred, determine whether the first touch sensing quantity is greater than the second touch sensing quantity; when the first touch sensing quantity is greater than the second touch sensing quantity, not report a touch sensing operation based on the corresponding touch area; and when the first touch sensing quantity is not greater than the second touch sensing quantity, report a touch sensing operation based on the corresponding touch area.

[0006] Based on the above, the embodiments of the present invention utilize two different touch charging periods and the corresponding changes in touch sensing quantity during the touch sensing period to determine whether there is a change in capacitance value caused by coupling capacitor in each touch area of ​​the touch layer. Thus, touch reporting is performed after correcting the capacitance value, reducing the situation of misjudging touch areas and avoiding many side effects caused by increasing the touch charging period. Simple Explanation of the Diagram

[0007] Figure 1 is a schematic diagram of a touch display device according to an embodiment of the present invention. Figure 2 is a schematic diagram of the touch area, data lines and coupling capacitors in one embodiment of the present invention. Figure 3 is a schematic diagram of the signal waveforms when there is no touch object on the touch area in one embodiment of the present invention. Figure 4 is a schematic diagram of the signal waveform located on the touch area in one embodiment. Figure 5 is a block diagram of a touch driving circuit according to an embodiment of the present invention. Figure 6 is a waveform diagram located on a touch area in one embodiment of the present invention. Figures 7A and 7B are flowcharts of a touch driving method for a touch display device according to an embodiment of the present invention. Figure 8 is a waveform diagram located on a touch area in several embodiments of the present invention. Implementation

[0008] Figure 1 is a schematic diagram of a touch display device 100 according to an embodiment of the present invention. Figure 2 is a schematic diagram of the touch areas Sx-1 to Sx-m, data lines 112-n, and coupling capacitors CC1 to CCk according to an embodiment of the present invention. The touch display device 100 mainly includes a display panel 105 and a controller 107.

[0009] The display panel 105 in this embodiment can be a liquid crystal display (LCD) panel, an organic light-emitting diode (OLED) panel, an active-matrix OLED panel, etc. The controller 107 can be a touch and display driver integrated (TDDI) chip. The controller 107 is applicable to active-matrix OLED driving technology and voltage-activated touch array (VOCTA) touch technology. The implementer does not limit the display driving technology and touch technology used in the controller 107. In addition to the display layer with display function, the display panel 105 in this embodiment also includes a touch layer 110.

[0010] As shown in Figure 1, the display panel 105 has multiple data lines (e.g., vertically oriented data lines 112-n, 112-n+1, ​​etc.) and multiple scan lines forming a pixel array. The touch layer 110 can be composed of multiple touch areas. For example, the touch layer 110 located above the data lines 112-n is composed of touch areas Sx-1 to Sx-m as shown in Figure 2. The touch display device 100 also includes a touch driving circuit (see touch driving circuit 500 in Figure 5), which can be disposed on either the display panel 105 or the controller 107. The touch driving circuit can be coupled to the touch areas located on the touch layer 110.

[0011] Figure 2 mainly shows the data lines 112-n on the display panel 105 and the corresponding touch areas Sx-1~Sx-m and the coupling capacitors CC1~CCm for easy explanation.

[0012] As shown in Figure 2, coupling capacitors (e.g., coupling capacitors CC1 to CCm in Figure 2) are provided between the data line 112-n and each touch area Sx-1 to Sx-m in the touch layer 110. On the other hand, during the touch sensing phase, the data line 112-n is set to a floating / High-Z state to prevent the pixel data in the pixel element coupled to the data line 112-n from being interfered with by touch sensing.

[0013] Please refer to Figures 1 and 2 simultaneously. During the touch sensing phase, when the user's finger 109 or other senseable object does not touch the touch layer 110, the data line 112-n is not affected by external interference, and the coupling capacitors CC1~CCm do not change their capacitance values. On the other hand, when a certain touch area in the touch layer 110 (e.g., touch area 112 in Figure 1, touch area Sx-k in Figure 2) is touched by the user's finger 109, since the user's finger can be considered as equivalent to ground, this touch area Sx-k has a coupling capacitor CCk with the corresponding data line 112-n. This causes all touch areas Sx-1~Sx-m corresponding to this data line 112-n to potentially change their capacitance values ​​due to the coupling capacitors CC1~CCm, which can easily lead to false alarms or misjudgments of touch areas in subsequent touch area determination. For example, the touch areas Sx-1 to Sx-m in Figure 2 are located in the range ETP in Figure 1. The touch areas in the range ETP in Figure 1 may all experience the aforementioned capacitance value changes, causing the range ETP to be considered as having contact with a finger 109 or other senseable objects.

[0014] Figure 3 is a schematic diagram of the signal waveforms in the touch area Sx-k in one embodiment of the present invention, when there is no touch object (e.g., finger 109). The signal 302, presented as a dashed line, represents the signal waveform of the touch area Sx-k during the touch sensing stage and when it is not affected by the finger 109 or other senseable objects. Because the touch layer 110 is not touched by the finger 109, the signal 302 presents a relatively perfect pulse waveform.

[0015] Signal 305, represented by a solid line, indicates the signal waveform of the touch area Sx-k during the touch sensing phase and influenced by the finger 109. Since the finger 109 can be considered as equivalent to ground, an increase in the equivalent capacitance of the coupling capacitor CCk will cause a change in the pulse waveform. For example, label 310 represents the voltage difference during touch charging period TP1, and label 320 represents the voltage difference during touch charging period TP2. The voltage difference will cause a change in capacitance value; the larger the voltage difference, the greater the change in capacitance value. Touch charging period TP1 is shorter than touch charging period TP2. As shown in Figure 3, during the touch sensing phase, the longer the touch charging period (e.g., touch charging period TP2 is longer than touch charging period TP1), the smaller the change in capacitance value. In other words, the touch sensing quantity will increase with the increase in touch charging period, which can also reduce the corresponding capacitance value change in the touch areas Sx-1~Sx-m caused by coupling capacitors CC1~CCm.

[0016] As shown in Figure 3, some embodiments can reduce the impact of capacitance changes by increasing the duration of the touch charging period. However, extending the duration of the touch charging period will cause many side effects, such as increasing the overall power consumption, lengthening the touch sensing operation time and compressing the time to the display stage, causing a decrease in the signal-to-noise ratio (SNR) of touch sensing without changing the overall operation time, and affecting the touch accuracy in some floating applications (e.g., touch while wearing gloves), etc.

[0017] This invention utilizes two different touch charging periods and the corresponding changes in touch sensing intensity during different touch sensing periods to determine whether there are capacitance changes in each touch area of ​​the touch layer caused by coupling capacitance. This allows for correction of the capacitance value before touch reporting, reducing misjudgments of touch areas and avoiding numerous side effects caused by increasing the touch charging period. For example, referring to Figure 3, the two touch charging periods TP1 and TP2 and their corresponding touch sensing intensity can be compared. When the first touch charging period TP1 is shorter than the second touch charging period TP2, the first touch sensing intensity corresponding to the first touch charging period TP1 is greater than the second touch sensing intensity corresponding to the second touch charging period TP2. This indicates that the touch sensing intensity in this area is caused by capacitance changes due to coupling capacitance. Conversely, the first touch sensing intensity corresponding to the first touch charging period TP1 in the area pressed by the touch object (finger) should not be greater than the second touch sensing intensity corresponding to the second touch charging period TP2.

[0018] The operation of the touch driving circuit 500 coupled to the touch area in the touch display device 100 is described herein. Figure 4 is a schematic diagram of signal waveforms located on the touch area (e.g., touch area Sx-1 in Figure 2) in one embodiment. Figure 5 is a block diagram of a touch driving circuit 500 coupled to the touch area according to an embodiment of the present invention.

[0019] Figure 4 illustrates the operation flow of the touch driving circuit 500 in the touch display device 100, which alternates between the display phase (DISP) and the touch sensing phase (TSP). In the display phase (DISP), the controller 107 in Figure 1 sequentially activates the scan lines and data lines according to the display flow to transmit display data to the corresponding pixel units. At this time, the touch areas do not have touch functionality; therefore, the touch driving circuit 500 provides a common voltage VCOM to each touch area during the display phase (DISP).

[0020] In the touch sensing phase (TSP), whether it's a touch signal TDP1 that's roughly at logic "1" or a touch signal TDP2 that's roughly at logic "0", each touch signal TDP1 and TDP2 is divided into four time periods: touch charging period DP, sampling period ADCP, virtual period DMP, and panel charging period CTP. In Figure 4, each time period in each touch signal TDP1 and TDP2 has the same duration. For example, each touch charging period DP in touch signals TDP1 and TDP2 has the same duration. Figures 4 and 5 mainly illustrate the operational details of the touch charging period DP, sampling period ADCP, virtual period DMP, and panel charging period CTP.

[0021] Figure 5 shows the touch driver circuit 500, which includes a touch area capacitor Cload, a driver Vdrive, switches SW1-SW3, an operational amplifier OP1, and an analog-to-digital converter (ADC). The touch area capacitor Cload represents the capacitance value on the touch area Sx. The touch area capacitor Cload is coupled to one end of switches SW1 and SW2. The output of the driver Vdrive is coupled to the other end of switch SW1. The inverting input of operational amplifier OP1 is coupled to the other end of switch SW2. The non-inverting input of operational amplifier OP1 is coupled to a reference voltage (e.g., ground voltage). The output of operational amplifier OP1 is coupled to the inverting input of operational amplifier OP1 through capacitor Cint, and the output of operational amplifier OP1 is coupled to one end of switch SW3. The input of the analog-to-digital converter (ADC) is coupled to the other end of switch SW3. The driver Vdrive can be implemented by operational amplifier OP2. The inverting input of operational amplifier OP2 is coupled to the output of operational amplifier OP2 as the output of driver Vdrive.

[0022] Please refer to Figures 4 and 5 simultaneously. During the touch charging period DP, switch SW2 is turned on and switches SW1 and SW3 are turned off. The charge on the touch area capacitor Cload flows to the inverting input of operational amplifier OP1 along the touch charging path DP_PTH to amplify the charge on the touch area capacitor Cload and become analog raw data at the output of operational amplifier OP1.

[0023] During the sampling period ADCP, switch SW3 is on while switches SW1 and SW2 are off. The analog raw data generated by operational amplifier OP1 is provided to the analog-to-digital converter ADC according to the sampling path ADCP_PTH. The analog-to-digital converter ADC converts the analog raw data into digital raw data. On the other hand, when the touch charging period DP switches to the sampling period ADCP, jitter will appear in the waveform.

[0024] In the virtual time period (DMP), switches SW1 through SW3 are all off. In other words, the virtual time period (DMP) is used to adjust the duration of touch signals TDP1 and TDP2.

[0025] During the panel charging period CTP, switch SW1 is turned on and switches SW2 and SW3 are turned off. The driver Vdrive charges the touch area capacitor Cload according to the panel charging path CTP_PTH.

[0026] Figure 6 is a waveform diagram of a touch area (e.g., touch area Sx-1 in Figure 2) according to an embodiment of the present invention. In Figure 6, the first touch sensing stage TSP1 in the touch sensing stage TSP includes a first touch signal. That is, the waveform formed by the alternation of the first sub-touch signal TDP1a and the second sub-touch signal TDP1b is shown in the lower left of Figure 6. The second touch sensing stage TSP2 in the touch sensing stage TSP includes a second touch signal. That is, the waveform formed by the alternation of the third sub-touch signal TDP2a and the fourth sub-touch signal TDP2b is shown in the lower right of Figure 6. In this embodiment, the first touch sensing stage TSP1 and the second touch sensing stage TSP2 are implemented alternately. In this embodiment, the first sub-touch signal TDP1a, the second sub-touch signal TDP1b, the third sub-touch signal TDP2a, and the fourth sub-touch signal TDP2b can be presented in the form of touch pulses.

[0027] In Figure 6, the first touch charging period DP1 is shorter than the second touch charging period DP2. Users of this embodiment can adjust the virtual periods DMP1 and DMP2 to make the first sub-touch signal TDP1a, the second sub-touch signal TDP1b, the third sub-touch signal TDP2a, and the fourth sub-touch signal TDP2b have the same duration. That is, the virtual period DMP1 in Figure 6 is longer than the virtual period DMP2. Users of this embodiment can also adjust the durations of the sampling periods ADCP1 and ADCP2 and the panel charging periods CTP1 and CTP2 as needed. In this embodiment, when the touch charging period length has been adjusted (e.g., the first touch charging period DP1 is shorter than the second touch charging period DP2), the durations of the virtual periods DMP1 and DMP2 can be adjusted to make the durations of the first sub-touch signal TDP1a and the second sub-touch signal TDP1b the same. In another embodiment, the length of the virtual time period can be adjusted without adjusting the length of the touch charging time period (e.g., the first touch charging time period DP1 is shorter than the second touch charging time period DP2), and the time lengths of TDP1a and TDP2a are different from each other.

[0028] In this embodiment of the invention, during the touch sensing period, two different touch charging periods (e.g., touch charging periods DP1 and DP2 of different durations in different touch sensing stages in Figure 6) and the corresponding changes in touch sensing quantity are used to determine whether there is a change in capacitance value caused by coupling capacitance in each touch area of ​​the touch layer. Thus, touch reporting is performed after correcting the capacitance value, reducing the situation of misjudging touch areas and avoiding the many side effects caused by increasing the touch charging period mentioned above.

[0029] In this embodiment, the first touch charging period DP1 can be set to 150 microseconds (µs), and the second touch charging period DP2 can be set to 200 microseconds (µs). In other embodiments conforming to the present invention, the time difference between the first touch charging period DP1 and the second touch charging period DP2 can be set to more than 1 microsecond (µs) to determine whether there is a change in capacitance value caused by coupling capacitance in each touch area of ​​the touch layer.

[0030] Figures 7A and 7B are flowcharts of a touch driving method for a touch display device according to an embodiment of the present invention. The touch driving method is applicable to the touch display device 100 of Figure 1. The touch display device 100 of Figure 1 includes a display panel 105, a touch driving circuit, and a controller 107. The display panel 105 of Figure 1 includes a touch layer 110. The touch layer 110 includes multiple touch areas. The touch driving circuit is coupled to the touch areas to obtain the original touch data corresponding to the touch areas. The controller 107 is coupled to the touch driving circuit to control the touch driving circuit to perform touch sensing operations.

[0031] Please refer to Figures 1, 6, 7A, and 7B simultaneously. In step S705 of Figure 7A, the controller 107 begins touch sensing. In step S710 of Figure 7A, the controller 107 sets a first touch signal having a first touch charging period DP1 and a second touch signal having a second touch charging period DP2. In this embodiment, the first touch signal includes a first sub-touch signal TDP1a located at a first logic value (e.g., logic "1") and a second sub-touch signal TDP1b located at a second logic value (e.g., logic "0"). In this embodiment, the first sub-touch signal TDP1a and the second sub-touch signal TDP1b have the same first touch charging period DP1. In addition to the first touch charging period DP1, the first sub-touch signal TDP1a and the second sub-touch signal TDP1b also include a sampling period ADCP1, a virtual period DMP1, and a panel charging period CTP1. The functions of the first touch charging period DP1, sampling period ADCP1, virtual period DMP1, and panel charging period CTP1 are the same as the operation details of the touch charging period DP, sampling period ADCP, virtual period DMP, and panel charging period CTP described in the foregoing embodiments.

[0032] In this embodiment, the first touch charging period DP1 is shorter than the second touch charging period DP2. The second touch signal in this embodiment includes a third sub-touch signal TDP2a located at a first logic value (e.g., logic "1") and a fourth sub-touch signal TDP2b located at a second logic value (e.g., logic "0"). In this embodiment, the third sub-touch signal TDP2a and the fourth sub-touch signal TDP2b have the same duration as the second touch charging period DP2. In addition to the second touch charging period DP2, the third sub-touch signal TDP2a and the fourth sub-touch signal TDP2b also include a sampling period ADCP2, a virtual period DMP2, and a panel charging period CTP2. The functions of the second touch charging period DP2, the sampling period ADCP2, the virtual period DMP2, and the panel charging period CTP2 are the same as the operational details of the touch charging period DP, the sampling period ADCP, the virtual period DMP, and the panel charging period CTP described in the previous embodiment.

[0033] In step S730, during the touch sensing stage TSP, the controller 107 controls the touch driving circuit coupled to the touch area based on the first touch signal (the signal waveform shown in the lower left corner of Figure 6) to obtain the first touch raw data corresponding to this touch area. For the method of obtaining the first touch raw data, please refer to the operational details of the corresponding embodiments in Figures 4 and 5 above.

[0034] In step S740, the controller 107 calculates a first touch sensing value based on the first touch raw data from step S730, and determines whether a touch has occurred based on this first touch sensing value. The first touch sensing value is a data value obtained by subtracting the raw data without finger touch (referred to here as background raw data) from the first touch raw data. The determination of whether a touch has occurred can be made by comparing this first touch sensing value with a preset touch threshold. When the first touch sensing value is greater than the preset touch threshold, it indicates that a touch has occurred; conversely, when the first touch sensing value is not greater than the preset touch threshold, it indicates that no touch has occurred.

[0035] If step S740 is negative, it indicates that no touch has occurred and the process proceeds to step S742, where the controller 107 reports the first touch data. The purpose of reporting this first touch data is to dynamically or adaptively adjust the values ​​of the background data, thereby more sensitively and accurately determining whether a touch has occurred.

[0036] In step S745, during the touch sensing stage TSP, the controller 107 controls the touch driving circuit coupled to the touch area based on the second touch signal (the signal waveform shown in the lower right corner of Figure 6) to obtain the second touch raw data corresponding to this touch area. For the method of obtaining the second touch raw data, please refer to the operational details of the corresponding embodiments in Figures 4 and 5 above.

[0037] In step S747, the controller 107 calculates a second touch sensing value based on the second touch raw data from step S745, and determines whether a touch has occurred based on this second touch sensing value. The second touch sensing value is a data value obtained by subtracting the raw data without finger touch (referred to here as background raw data) from the second touch raw data. The determination of whether a touch has occurred can be made by comparing this second touch sensing value with a preset touch threshold. When this second touch sensing value is greater than the preset touch threshold, it indicates that a touch has occurred; conversely, when this second touch sensing value is not greater than the preset touch threshold, it indicates that no touch has occurred. Users of this embodiment can set the background raw data and the preset touch threshold in steps S740 and S747 according to their needs. Furthermore, the background raw data and the preset touch threshold in step S740 may be different from the background raw data and the preset touch threshold in step S747.

[0038] If step S747 is negative, it indicates that no touch has occurred and the process proceeds to step S749, where the controller 107 reports this second touch data. The purpose of reporting this second touch data is to dynamically or adaptively adjust the values ​​of the background data, thereby more sensitively and accurately determining whether a touch has occurred. After step S749 is completed, the process returns to step S730 to continuously perform touch detection and utilize two different touch charging periods and corresponding changes in touch sensitivity to determine whether the touch area's capacitance change is caused by a coupling capacitor.

[0039] Returning to step S740. If step S740 is true, it indicates that a touch has occurred based on the first touch sensing value in step S740. Therefore, the process proceeds from step S740 to step S741, where the controller 107 acquires the second touch sensing value of the second touch signal, and then proceeds from step S741 to step S750. In step S750, the controller 107 determines whether the first touch sensing value in step S740 is greater than the second touch sensing value corresponding to the second touch signal.

[0040] Since the first touch charging period DP1 is shorter than the second touch charging period DP2, when step S750 determines that the first touch sensing quantity is greater than the second touch sensing quantity, it indicates that the touch sensing quantity of this touch area is generated based on the capacitance value change caused by the coupling capacitor. Therefore, from step S750 to step S760, the controller 107 does not report touch sensing operations based on this touch area corresponding to the aforementioned first and second touch sensing quantities. Furthermore, the controller 107 performs algorithmic processing on the first and second touch sensing quantities of this touch area to adaptively adjust the background raw data, the preset touch threshold, or the corresponding value. The purpose of the algorithm described in this embodiment is to eliminate the touch sensing quantity of this touch area corresponding to the capacitance value change caused by the coupling capacitor (i.e., the aforementioned first and second touch sensing quantities) to avoid false alarms in subsequent touch sensing operations. After step S760 is completed, step S780 is executed.

[0041] On the other hand, when step S750 determines that the first touch sensing value is not greater than the second touch sensing value, it indicates that the first and second touch sensing values ​​of this touch area are generated based on the touch object (e.g., a finger). Therefore, from step S750 to step S770, the controller 107 determines that both the first and second touch sensing values ​​of this touch area are touch sensing values ​​of the touch object. In step S772, the controller 107 corrects the first and second touch sensing values ​​of step S770 through the gain lookup table corresponding to the first and second touch signals, and in step S780, it reports the touch sensing operation based on the corrected first touch sensing value. The purpose of the correction in step S772 of this embodiment is to adjust the values ​​of the first and second touch sensing values ​​to a consistent range so that the touch sensing operation is more accurate. After step S772 is completed, step S780 is entered. In step S780, the controller 107 reports the touch sensing operation based on the results of steps S760 and S772. After step S780 is completed, the process can return to step S730 to continue this touch driving method.

[0042] Returning to step S747. If step S747 is true, it indicates that a touch has occurred based on the second touch sensing value in step S747. Therefore, the process proceeds from step S747 to step S748, where the controller 107 acquires the first touch sensing value of the first touch signal and proceeds from step S748 to step S750, continuing to execute steps S750 to S780. The operations of steps S750 to S780 are described above.

[0043] The signal waveform shown in Figure 6 is consistent with one implementation of various embodiments of the present invention, in which a first touch sensing stage TSP1, including a first touch signal (e.g., a first sub-touch signal TDP1a and a second sub-touch signal TDP1b), and a second touch sensing stage TSP2, including a second touch signal (e.g., a second sub-touch signal TDP2a and a second sub-touch signal TDP2b), are performed alternately. On the other hand, users of this embodiment can arbitrarily combine the first touch signal (e.g., one of the first sub-touch signal TDP1a and the second sub-touch signal TDP1b) with the second touch signal (e.g., one of the third sub-touch signal TDP2a and the fourth sub-touch signal TDP2b). As long as each touch sensing stage TSP includes at least one first touch signal and at least one second touch signal, the touch driving method described in Figures 7A and 7B can be implemented, as shown in Figure 8.

[0044] Figure 8 shows a variety of signal waveforms that the TSP may contain different touch charging periods (e.g., the first touch charging period in the first sub-touch signal TDP1a or the second sub-touch signal TDP1b, and the second touch charging period in the third sub-touch signal TDP2a or the fourth sub-touch signal TDP2b) during a single touch sensing phase.

[0045] For example, in Figure 8, each touch sensing stage TSP includes a first touch charging period in the first sub-touch signal TDP1a or the second sub-touch signal TDP1b, and a second touch charging period in the third sub-touch signal TDP2a or the fourth sub-touch signal TDP2b. The signal waveform (A) in the first row at the bottom left of Figure 8 is composed of the first sub-touch signal TDP1a, the fourth sub-touch signal TDP2b, the first sub-touch signal TDP1a, and the fourth sub-touch signal TDP2b in sequence; the signal waveform (B) in the second row at the bottom left of Figure 8 is composed of the third sub-touch signal TDP2a, the second sub-touch signal TDP1b, the first sub-touch signal TDP1a, and the fourth sub-touch signal TDP2b in sequence; the signal waveform (C) in the third row (last row) at the bottom left of Figure 8 is composed of the third sub-touch signal TDP2a, the fourth sub-touch signal TDP2b, the first sub-touch signal TDP1a, and the second sub-touch signal TDP1b in sequence. The signal waveform (D) in the first row of the lower right corner of Figure 8 is composed of the first sub-touch signal TDP1a, the second sub-touch signal TDP1b, the third sub-touch signal TDP2a, and the fourth sub-touch signal TDP2b in sequence. The signal waveform (E) in the second row of the lower right corner of Figure 8 is composed of the first sub-touch signal TDP1a, the fourth sub-touch signal TDP2b, the third sub-touch signal TDP2a, and the second sub-touch signal TDP1b in sequence. The signal waveform (F) in the third (last) row of the lower right corner of Figure 8 is composed of the third sub-touch signal TDP2a, the second sub-touch signal TDP1b, the third sub-touch signal TDP2a, and the second sub-touch signal TDP1b in sequence. The signal waveforms (A)-(F) in Figure 8 include at least one first touch signal and at least one second touch signal. By selecting one of the signal waveforms (A)-(F) in Figure 8 or by presenting a combination of these signal waveforms (A)-(F) in each touch sensing stage TSP, the touch driving method described in Figures 7A and 7B can also be realized.

[0046] Referring to the signal waveform (A) in Figure 8, the first touch sensing stage in the touch sensing stage TSP includes a first touch signal (e.g., a first sub-touch signal TDP1a located at a first logic value and having a first touch charging period), and the second touch sensing stage in the touch sensing stage TSP includes a second touch signal (e.g., a fourth sub-touch signal TDP2b located at a second logic value and having a second touch charging period), and the first touch sensing stage and the second touch sensing stage are implemented alternately. Referring to the signal waveform (B) in Figure 8, the first second touch sensing stage in the touch sensing stage TSP includes a second touch signal (e.g., a third sub-touch signal TDP2a located at a first logic value and having a second touch charging period), the first first touch sensing stage in the touch sensing stage TSP includes a first touch signal (e.g., a second sub-touch signal TDP1b located at a second logic value and having a first touch charging period), the next first touch sensing stage in the touch sensing stage TSP includes a first touch signal (e.g., a first sub-touch signal TDP1a located at a first logic value and having a first touch charging period), and the next second touch sensing stage in the touch sensing stage TSP includes a second touch signal (e.g., a fourth sub-touch signal TDP2b located at a second logic value and having a second touch charging period). Referring to the signal waveforms (C) and (D) in Figure 8, the first touch sensing stage in the touch sensing stage TSP includes a first touch signal (e.g., a first sub-touch signal TDP1a located at a first logic value and having a first touch charging period and a second sub-touch signal TDP1b located at a second logic value and having a first touch charging period), and the second touch sensing stage in the touch sensing stage TSP includes a second touch signal (e.g., a third sub-touch signal TDP2a located at a first logic value and having a second touch charging period and a fourth sub-touch signal TDP2b located at a second logic value and having a second touch charging period), and the first touch sensing stage and the second touch sensing stage are implemented alternately. Referring to the signal waveform (E) in Figure 8, the first first touch sensing stage in the touch sensing stage TSP includes a first touch signal (e.g., a first sub-touch signal TDP1a located at a first logic value and having a first touch charging period), the first second touch sensing stage in the touch sensing stage TSP includes a second touch signal (e.g., a fourth sub-touch signal TDP2b located at a second logic value and having a second touch charging period), the next second touch sensing stage in the touch sensing stage TSP includes a first touch signal (e.g., a third sub-touch signal TDP2a located at a first logic value and having a second touch charging period), and the next first touch sensing stage in the touch sensing stage TSP includes a first touch signal (e.g., a second sub-touch signal TDP1b located at a second logic value and having a first touch charging period).Referring to the signal waveform (F) in Figure 8, the first touch sensing stage in the touch sensing phase TSP includes a first touch signal (e.g., a second sub-touch signal TDP1b located at a second logic value and having a first touch charging period), and the second touch sensing stage in the touch sensing phase TSP includes a second touch signal (e.g., a third sub-touch signal TDP2a located at a first logic value and having a second touch charging period), and the first touch sensing stage and the second touch sensing stage are implemented alternately.

[0047] In summary, the embodiments of the present invention utilize two different touch charging periods and the corresponding changes in touch sensing quantity during touch sensing to determine whether there are capacitance changes caused by coupling capacitors in each touch area of ​​the touch layer. Thus, touch reporting is performed after correcting the capacitance value, reducing the possibility of misjudging touch areas.

[0048] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

[0049] 100: Touch display device 105: Display Panel 107: Controller 109: Fingers 110: Touch layer 112: Touch Area 112-n, 112-n+1: Data lines 302, 305: Signals 310, 320: Marked S705~S780: Steps in the touch driving method of a touch display device Sx, Sx-1~Sx-m, Sx-k: Touch area CC1~CCm, CCk: Coupling capacitors ETP: Range TP1, TP2, DP1, DP2, DP: Touchscreen charging period DISP: Display Phase TSP: Touch Sensing Phase TSP1: First Touch Sensing Stage TSP2: Second Touch Sensing Stage ADCP, ADCP1, ADCP2: Sampling period DMP, DMP1, DMP2: Virtual Time Periods CTP, CTP1, CTP2: Panel charging period VCOM: Common Voltage TDP1, TDP2: Touch signals Cload: Touch area capacitance Vdrive: drive SW1~SW3: Switches OP1, OP2: Operational amplifiers ADC: Analog-to-Digital Converter CTP_PTH: Panel charging path DP_PTH: Touch charging path ADCP_PTH: Sampling path TDP1a: First sub-touch signal TDP1b: Second sub-touch signal TDP2a: Third Sub-Touch Signal TDP2b: Fourth Sub-Touch Signal

Claims

1. A touch driving method for a touch display device, comprising: A first touch signal with a first touch charging period and a second touch signal with a second touch charging period are defined, wherein the first touch charging period is shorter than the second touch charging period. During the touch sensing phase, a touch driving circuit coupled to a touch area is controlled based on the first touch signal and the second touch signal to obtain first touch raw data and second touch raw data corresponding to the touch area. A first touch sensing value is calculated based on the first touch raw data, a second touch sensing value is calculated based on the second touch raw data, and a touch is determined based on the first touch sensing value or the second touch sensing value. When a touch is determined to have occurred, it is determined whether the first touch sensing value is greater than the second touch sensing value. When the first touch sensing value is greater than the second touch sensing value, no touch sensing operation is reported based on the corresponding touch area; and when the first touch sensing value is not greater than the second touch sensing value, the touch sensing operation is reported based on the corresponding touch area.

2. The touch driving method as described in claim 1 further includes: When it is determined that no touch has occurred based on the first touch sensing amount or the second touch sensing amount, the first touch original data or the second touch original data is returned.

3. The touch driving method as described in claim 1 further includes: After reporting a point that does not perform the touch sensing operation based on the corresponding touch area, the touch area is processed by an algorithm, wherein the algorithm is to remove the touch sensing amount of the corresponding touch area.

4. The touch driving method as described in claim 1, wherein, The step of reporting a touch sensing operation based on the corresponding touch area includes: correcting the numerical values ​​of the first touch sensing quantity and the second touch sensing quantity to adjust them to a consistent range; and reporting a touch sensing operation based on the corrected first touch sensing quantity or the corrected second touch sensing quantity and the corresponding touch area.

5. The touch driving method as claimed in claim 1, wherein the first touch sensing stage in the touch sensing stage includes the first touch signal, the second touch sensing stage in the touch sensing stage includes the second touch signal, and the first touch sensing stage and the second touch sensing stage are implemented alternately.

6. The touch driving method as claimed in claim 1, wherein the first touch signal includes a first sub-touch signal located at a first logic value and a second sub-touch signal located at a second logic value, the second touch signal includes a third sub-touch signal located at the first logic value and a fourth sub-touch signal located at the second logic value, wherein the first sub-touch signal includes a first sampling period, a first virtual period, and a first panel charging period in addition to the first touch charging period, and the second sub-touch signal includes a second sampling period, a second virtual period, and a second panel charging period in addition to the second touch charging period.

7. The touch driving method as described in claim 6, wherein, When the first touch charging period is shorter than the second touch charging period, the first virtual period and the second virtual period are adjusted so that the duration of the first sub-touch signal and the second sub-touch signal are the same; or, when the first touch charging period is shorter than the second touch charging period, the duration of the first sub-touch signal and the second sub-touch signal are different.

8. The touch driving method as claimed in claim 1, wherein the touch sensing phase includes the first touch charging period and the second touch charging period.

9. The touch driving method as claimed in claim 8, wherein the first touch charging period and the second touch charging period are implemented alternately.

10. The touch driving method of claim 8, wherein the first touch signal includes a first touch charging period at a first logic value and a second touch charging period at a second logic value, the second touch signal includes a second touch charging period at the first logic value and a first touch charging period at the second logic value, and the first touch signal and the second touch signal are implemented alternately.

11. A touch display device, comprising: The display panel includes a touch layer, the touch layer including multiple touch areas; A touch driving circuit is coupled to the touch area to obtain the original touch data corresponding to the touch area; A controller, coupled to the touch driving circuit, controls the touch driving circuit to perform touch sensing operations. The controller is configured to: set a first touch signal having a first touch charging period and a second touch signal having a second touch charging period, wherein the first touch charging period is shorter than the second touch charging period; during the touch sensing phase, control the touch driving circuit coupled to the touch area based on the first touch signal and the second touch signal to obtain first touch raw data and second touch raw data corresponding to the touch area; calculate a first touch sensing value based on the first touch raw data, calculate a second touch sensing value based on the second touch raw data, and determine whether a touch has occurred based on the first touch sensing value or the second touch sensing value; when a touch is determined to have occurred, determine whether the first touch sensing value is greater than the second touch sensing value; when the first touch sensing value is greater than the second touch sensing value, not report a touch sensing operation based on the corresponding touch area; and when the first touch sensing value is not greater than the second touch sensing value, report a touch sensing operation based on the corresponding touch area.

12. The touch display device of claim 11, wherein the controller is further configured to: when it is determined, based on the first touch sensing amount or the second touch sensing amount, that no touch has occurred, report the first touch raw data or the second touch raw data.

13. The touch display device as claimed in claim 11, wherein the controller is further configured to: after reporting a touch sensing operation not based on the corresponding touch area, perform algorithmic processing on the touch area, wherein, The algorithm is to remove the touch sensing data corresponding to the touch area.

14. The touch display device of claim 11, wherein the controller is further configured to: correct the numerical values ​​of the first touch sensing quantity and the second touch sensing quantity to adjust them to a consistent range, and report the touch sensing operation based on the corrected first touch sensing quantity or the corrected second touch sensing quantity and the corresponding touch area.

15. The touch display device of claim 11, wherein the first touch sensing stage in the touch sensing stage includes the first touch signal, the second touch sensing stage in the touch sensing stage includes the second touch signal, and the first touch sensing stage and the second touch sensing stage are implemented alternately.

16. The touch display device of claim 11, wherein the first touch signal includes a first sub-touch signal located at a first logic value and a second sub-touch signal located at a second logic value, the second touch signal includes a third sub-touch signal located at the first logic value and a fourth sub-touch signal located at the second logic value, wherein the first sub-touch signal includes a first sampling period, a first virtual period, and a first panel charging period in addition to the first touch charging period, and the second sub-touch signal includes a second sampling period, a second virtual period, and a second panel charging period in addition to the second touch charging period.

17. The touch display device as claimed in claim 16, wherein, When the first touch charging period is shorter than the second touch charging period, the first virtual period and the second virtual period are adjusted so that the duration of the first sub-touch signal and the second sub-touch signal are the same; or, when the first touch charging period is shorter than the second touch charging period, the duration of the first sub-touch signal and the second sub-touch signal are different.

18. The touch display device of claim 11, wherein the touch sensing phase includes the first touch charging period and the second touch charging period.

19. The touch display device as claimed in claim 18, wherein the first touch charging period and the second touch charging period are implemented alternately.

20. The touch display device of claim 18, wherein the first touch signal includes a first touch charging period at a first logic value and a second touch charging period at a second logic value, the second touch signal includes a second touch charging period at the first logic value and a first touch charging period at the second logic value, and the first touch signal and the second touch signal are implemented alternately.

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