Capacitive touch sensing device and touch sensing method

Abstract

A capacitive touch sensing device and a touch sensing method. The capacitive touch sensing device includes a touch panel and a touch sensing control circuit. The touch electrode layer of the touch panel includes a plurality of first electrodes extending along a first direction and a plurality of second electrodes extending along a second direction. At a first time, the touch sensing control circuit provides a first driving signal to a part of the driving electrodes and a second driving signal to another part of the driving electrodes, and receives a sensing capacitance generated by the sensing electrodes. The first driving signal and the second driving signal are non-coherent pulse signals. At a second time, the touch sensing control circuit provides a third driving signal which is coherent to each of the driving electrodes, calculates a capacitance change of the sensing capacitance of a same sensing electrode at the first time and the second time, and identifies a touch object at a position corresponding to the sensing electrode as a ground conductor when the capacitance change is greater than or equal to a preset value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of touch sensing, and particularly relates to a capacitive touch sensing device and a touch sensing method. BACKGROUND

[0002] Capacitive touch sensing devices include self-capacitive and mutual-capacitive. Taking a mutual-capacitive touch sensing device as an example, it includes at least one drive electrode and at least one sense electrode below a cover plate. During touch sensing, the drive electrode is driven by a drive voltage, and a sense capacitor between the sense electrode and the drive electrode is sensed. When a touch operation is performed on the cover plate by using a finger or a grounded conductor, the capacitance value of the sense capacitor will change. When a non-grounded conductor (such as a water droplet, water mist, a coin, etc.) exists on the cover plate, the capacitance value of the sense capacitor will also change, which will cause the touch sensing device to identify the non-grounded conductor as a grounded conductor, and thus cause false sensing. SUMMARY

[0003] The main purpose of the present application is to provide a capacitive touch sensing device and a touch sensing method, which aims to solve the problem of how to avoid false sensing of a non-grounded conductor in the prior art.

[0004] A capacitive touch sensing device includes a touch panel and a touch sensing control circuit; the touch panel includes a cover plate and a touch electrode layer which are sequentially stacked from top to bottom; the touch electrode layer is patterned to form a plurality of first electrodes extending along a first direction and a plurality of second electrodes extending along a second direction; the touch sensing control circuit is electrically connected with the first electrodes and the second electrodes; the touch sensing stage includes at least one first time and at least one second time; in the first time and the second time, the first electrodes serve as driving electrodes and the second electrodes serve as sensing electrodes; in the first time, the touch sensing control circuit provides a first driving signal to a part of the driving electrodes, provides a second driving signal to another part of the driving electrodes, and receives a sensing capacitance generated by each of the sensing electrodes; wherein the first driving signal and the second driving signal are non-coherent pulse signals; in the second time, the touch sensing control circuit provides a third driving signal to each of the driving electrodes, and receives a sensing capacitance generated by each of the sensing electrodes; the third driving signal received by each of the driving electrodes is a coherent pulse signal; the touch sensing control circuit further calculates a capacitance change of the sensing capacitance sensed by a same sensing electrode in the first time and the sensing capacitance sensed by the same sensing electrode in the second time, and compares the capacitance change with a preset value; when the capacitance change is greater than or equal to the preset value, the touch sensing control circuit identifies that a touch object corresponding to the sensing electrode is a grounded conductor; when the capacitance change is less than the preset value, the touch sensing control circuit identifies that the touch object corresponding to the sensing electrode is a non-grounded conductor; the non-coherent pulse signal is a pulse signal with at least one of frequency, amplitude and phase different; the coherent pulse signal is a pulse signal with frequency, amplitude and phase all the same.

[0005] In addition, in order to achieve the above-mentioned purpose, the application further provides a touch sensing method applied to a capacitive touch sensing device, the capacitive touch sensing device including a touch panel and a touch sensing control circuit; the touch panel includes a cover plate and a touch electrode layer which are sequentially stacked from top to bottom; the touch electrode layer is patterned to form a plurality of first electrodes extending along a first direction and a plurality of second electrodes extending along a second direction; wherein at any time in a touch sensing stage, one of the first electrodes and the second electrodes serves as a driving electrode and the other serves as a sensing electrode; the touch sensing control circuit is electrically connected with the first electrodes and the second electrodes; the touch sensing method includes:

[0006] setting the first electrodes as the driving electrodes and setting the second electrodes as the sensing electrodes;

[0007] providing a first driving signal to a part of the driving electrodes and a second driving signal to another part of the driving electrodes at a first time, and receiving a sensing capacitance generated by each of the sensing electrodes; wherein the first driving signal and the second driving signal are non-co-phase pulse signals;

[0008] providing a third driving signal to each of the driving electrodes at a second time, and receiving a sensing capacitance generated by each of the sensing electrodes, wherein the third driving signal received by each of the driving electrodes is a co-phase pulse signal;

[0009] calculating a capacitance variation of the sensing capacitance sensed by the same sensing electrode at the first time and the sensing capacitance sensed by the same sensing electrode at the second time;

[0010] judging whether the capacitance variation is greater than or equal to a preset value;

[0011] when the capacitance variation is less than the preset value, identifying the touch object corresponding to the position of the sensing electrode as a non-ground conductor;

[0012] when the capacitance variation is greater than or equal to the preset value, identifying the touch object corresponding to the position of the sensing electrode as a ground conductor;

[0013] the non-co-phase pulse signal is a pulse signal with at least one of frequency, amplitude and phase being different; and the co-phase pulse signal is a pulse signal with all of frequency, amplitude and phase being the same.

[0014] The capacitive touch sensing device and the touch sensing method, by providing a non-co-phase driving signal to the driving electrodes at one time in the touch sensing stage and providing a co-phase driving signal to each of the driving electrodes at another time in the touch sensing stage, detecting a variation degree of the sensing capacitance received by the same sensing electrode at two different times, identifying as a non-ground conductor when the variation degree of the sensing capacitance is small, excluding the false sensing generated by the non-ground conductor, and further avoiding the capacitive touch sensing device from generating false sensing, so as to improve the accuracy of touch detection of the capacitive touch sensing device. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on the provided drawings.

[0016] Figure 1 It is a schematic diagram of the capacitive touch sensing device of the preferred embodiment of the present application.

[0017] Figure 2 For Figure 1 The schematic diagram of the touch electrode layer in the application.

[0018] Figure 3 For Figure 2 The schematic diagram of the touch electrode layer and its loading signal at the first time t1 in the application.

[0019] Figure 4 For Figure 2 The schematic diagram of the touch electrode layer and its loading signal at the first time t2 in the application.

[0020] Figure 5 For Figure 2 The schematic diagram of the sensing capacitance change of the sensing electrode at the first time t1 and the first time t2 in the application.

[0021] Figure 6 The flow chart of the touch sensing method of the preferred embodiment of the application.

[0022] Figure 7 For Figure 6 The flow chart of the touch sensing method in the application.

[0023] Main element symbol explanation

[0024] Capacitive touch sensing device 1

[0025] Touch panel 10

[0026] Display panel 20

[0027] Cover plate 11

[0028] Touch electrode layer 12

[0029] First electrode 121_1-121_m

[0030] Second electrode 123_1-123_n

[0031] Driving electrode Tx1-Txm, Tx1-Txn

[0032] Sensing electrode Rx1-Rxn, Rx1-Rxm

[0033] Touch display area 101

[0034] Non-display area 103

[0035] Touch sensing control circuit 30

[0036] Touch sensing line 31

[0037] Steps S600-S614

[0038] The following detailed description will further describe the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0039] In order to make the persons skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by the persons skilled in the art without creative labor should belong to the protection scope of the present application.

[0040] The terms "first", "second", and "third" and the like in the description of the present application and the above-mentioned drawings are used to distinguish different objects, but not to describe a particular order. In addition, the term "comprising" and any variations thereof are intended to cover non-exclusive inclusion.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein only for the purpose of describing specific embodiments, and is not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0042] The specific embodiments of the capacitive touch sensing device and the touch sensing method of the present application will be described below in conjunction with the drawings.

[0043] Please refer to Figure 1 , which is a schematic diagram of a capacitive touch sensing device 1. The capacitive touch sensing device 1 can be a mobile device such as a personal computer, a tablet computer, a smart phone, a personal digital assistant (PDA), a game console, an interactive Internet Protocol Television (IPTV), a smart wearable device, a navigation device, etc., or a fixed device such as a desktop computer, a server, a digital television, etc. The capacitive touch sensing device 1 can further include one or more combinations of a fingerprint recognition function, a display function, and a camera function.

[0044] The capacitive touch sensing device 1 includes a touch panel 10 and a display panel 20. The touch panel 10 is used to sense a touch operation of a user. The touch panel 10 includes a cover plate 11 and a touch electrode layer 12 which are sequentially stacked from top to bottom.

[0045] The cover plate 11 can be a glass substrate or other transparent substrate with high strength and high hardness. In at least one embodiment of the present application, the cover plate 11 can be made of materials such as polycarbonate (PC), polythylene terephthalate (PET), polymethylmethacrylate (PMMA), cyclic olefin copolymer (COC), or polyether sulfone (PES).

[0046] Please refer to Figure 2 , which is a schematic diagram of a module of the touch electrode layer 12. The touch electrode layer 12 is made of conductive material and can be patterned to form a plurality of first electrodes 121_1-121_m and a plurality of second electrodes 123_1-123_n. Wherein, m and n are positive integers, and they can be the same or different. A plurality of first electrodes 121_1-121_m extend along the first direction X and are arranged parallel to each other, and a plurality of second electrodes 123_1-123_n extend along the second direction Y and are arranged parallel to each other. In at least one embodiment of the present application, the first direction X is perpendicular to the second direction Y. In other embodiments, the first direction X and the second direction Y can be arranged at other angles. At any time during the touch sensing stage T1, one of the first electrodes 121_1-121_m and the second electrodes 123_1-123_n acts as a drive electrode Tx1-Txm (as shown in Figure 3 ), and the other acts as a sense electrode Rx1-Rxn (as shown in Figure 3 ). When a ground conductor (such as a finger or a stylus) is present on the cover plate 11, the induced capacitance between the sense electrode Rx and the drive electrode decreases. In the present embodiment, the touch electrode layer 12 is a two-layer conductive structure to form a mutual-capacitance touch sensing structure.

[0047] In other embodiments of the present application, the touch electrode layer 12 can be a single-layer conductive structure to form a self-capacitance touch sensing structure.

[0048] The display panel 20 is located below the touch panel 10 and is used to display images. In at least one embodiment of the present application, the display panel 20 is an OLED display structure, which can include a first electrode layer, a second electrode layer, a hole injection layer, a hole transport layer, a light-emitting layer, and an electron injection layer. In other embodiments, the display panel 20 can also be a liquid crystal display structure or other display structure.

[0049] Further, refer to Figure 1The capacitive touch sensing device 1 defines a touch display area 101 and a non-display area 103 surrounding the touch display area 101. A plurality of the first electrodes 121_1-121_m and a plurality of the second electrodes 123_1-123_n are located in the touch display area 101 and can extend into the non-display area 103.

[0050] Reference Figure 2 The capacitive touch sensing device 1 further includes a touch sensing control circuit 30. The touch sensing control circuit 30 can be disposed in the non-display area 103 and electrically connected to the plurality of the first electrodes 121_1-121_m and the plurality of the second electrodes 123_1-123_n through a touch sensing line 31. The touch sensing control circuit 30 is configured to provide driving signals to the plurality of the driving electrodes Tx1-Txm and receive sensing capacitances generated by each of the sensing electrodes Rx1-Rxn during the touch sensing stage T1. In at least one embodiment of the present application, the touch sensing control circuit 30 takes the driving electrodes Tx1-Txm as the first electrodes 121_1-121_m and takes the sensing electrodes Rx1-Rxn as the second electrodes 123_1-123_n.

[0051] The capacitive touch sensing device 1 works as follows:

[0052] The touch sensing stage T1 includes at least one first time t1 and at least one second time t2. The first time t1 and the second time t2 are alternately arranged.

[0053] Please refer to Figure 3 which is a schematic view of the touch electrode layer 12 and the signals loaded thereon at the first time t1. At the first time t1, the touch sensing control circuit 30 provides a first driving signal DR1 to a portion of the driving electrodes Tx1-Txm and provides a second driving signal DR2 to another portion of the driving electrodes Tx1-Txm, and receives sensing capacitances S1-Sn generated by each of the sensing electrodes Rx1-Rxn. The first driving signal DR1 and the second driving signal DR2 are non-coherent pulse signals. In at least one embodiment of the present application, the non-coherent pulse signal is a pulse signal with at least one of frequency, amplitude and phase different; and the coherent pulse signal is a pulse signal with all of frequency, amplitude and phase same. It can be understood that the amplitude and phase of the coherent pulse signal can have slight deviation due to signal loss or other reasons, but the frequency of the coherent pulse signal must be consistent. For example, the first driving signal DR1 and the second driving signal DR2 are different in frequency, amplitude or phase. Figure 3 For example, the first driving signal DR1 and the second driving signal DR2 are different in frequency, amplitude or phase.

[0054] In at least one embodiment of the present application, at the first time t1, the touch control circuit 30 provides the first driving signal DR1 to the odd-numbered electrodes among the driving electrodes Tx1~Txm and provides the second driving signal DR2 to the even-numbered electrodes among the driving electrodes Tx1~Txm. In other embodiments, at the first time t1, the touch control circuit 30 can also provide the first driving signal DR1 or the second driving signal DR2 to the driving electrodes Tx1~Txm at specific positions. For example, at the first time t1, the touch control circuit 30 can provide the first driving signal DR1 to the driving electrodes Tx2~Tx(m-1) at the middle of the touch display area 101 and provide the second driving signal DR2 to the driving electrodes Tx1 and Txm at the edges of the touch display area 101.

[0055] In at least one embodiment of the present application, at the first time t1, the touch control circuit 30 receives the sensing capacitances S1~Sn generated by each of the sensing electrodes Rx1~Rxn at the same time. In this mode, the capacitive touch sensing device 1 has a higher cost but a faster signal sensing time. In other embodiments, the touch control circuit 30 can also receive the sensing capacitances S1~Sn generated by each of the sensing electrodes Rx1~Rxn at different times. For example, at the first time t1, the touch control circuit 30 receives the sensing capacitances S1~Si generated by the sensing electrodes Rx1~Rxi, and at other times between the first time t1 and the second time t2, the touch control circuit 30 receives the sensing capacitances S(i+1)~Sn generated by the sensing electrodes Rx(i+1)~Rxn. Here, i is a positive integer greater than 1 and less than n. In this mode, the capacitive touch sensing device 1 has a lower cost but a slower signal sensing time.

[0056] Please refer to Figure 4 which is a schematic diagram of the touch electrode layer 12 and the signals loaded thereon at the second time t2. At the second time t2, the touch control circuit 30 provides a third driving signal DR3 to each of the driving electrodes Tx1~Txm and receives the sensing capacitances generated by each of the sensing electrodes Rx1~Rxn. The third driving signal DR3 received by each of the driving electrodes Tx1~Txm is a same-phase pulse signal.

[0057] In at least one embodiment of the present application, the third driving signal DR3 is a same phase signal as the first driving signal DR1. In other embodiments, the third driving signal DR3 can also be a same phase signal as the second driving signal DR2. Alternatively, the third driving signal DR3 can also be another driving signal different from the first driving signal DR1 and the second driving signal DR2.

[0058] The touch sensing control circuit 30 calculates the capacitance change of the sensing capacitance Si_t1~Si_t1 sensed by the same sensing electrode Rxi in the sensing electrodes Rx1~Rxn at the first time t1 and the sensing capacitance Si_t2~Si_t2 sensed by the same sensing electrode Rxi at the second time t2. When the capacitance change is greater than or equal to a preset value, the touch sensing control circuit 30 identifies the touch object at the position corresponding to the sensing electrode Rxi as a non-ground conductor (e.g., a water droplet, water mist, a coin, etc.). When the capacitance change is less than the preset value, the touch sensing control circuit 30 identifies the touch object at the position corresponding to the sensing electrode Rxi as a ground conductor.

[0059] Please refer to Figure 5 , which is a schematic diagram of the sensing capacitance change of the sensing electrodes Rx1~Rx36 at the first time t1 and the second time t2. It is assumed that the preset value is 500 units. The sensing capacitance value of the sensing electrode Rx11 at the first time t1 is 1506 units, and the sensing capacitance value at the second time t2 is 572; the sensing capacitance value of the sensing electrode Rx12 at the first time t1 is 2108, and the sensing capacitance value at the second time t2 is 952; the sensing capacitance value of the sensing electrode Rx13 at the first time t1 is 1244, and the sensing capacitance value at the second time t2 is 464. Among them, the sensing capacitance change of the sensing electrode Rx11 at the first time t1 and the second time t2 is 934, which is greater than or equal to the preset value, so the touch sensing control circuit 30 identifies the touch object corresponding to the position of the sensing electrode Rx11 as a ground conductor. Similarly, the touch sensing control circuit 30 identifies the touch objects corresponding to the positions of the sensing electrode Rx12 and the sensing electrode Rx13 as ground conductors.

[0060] Meanwhile, the sensing electrode Rx23 has a sensing capacitance value of 214 at the first time t1 and a sensing capacitance value of -8 at the second time t2; the sensing electrode Rx24 has a sensing capacitance value of 348 at the first time t1 and a sensing capacitance value of -16 at the second time t2; the sensing electrode Rx25 has a sensing capacitance value of 406 at the first time t1 and a sensing capacitance value of -12 at the second time t2; the sensing electrode Rx26 has a sensing capacitance value of 316 at the first time t1 and a sensing capacitance value of -16 at the second time t2; the sensing electrode Rx27 has a sensing capacitance value of 292 at the first time t1 and a sensing capacitance value of -8 at the second time t2; the sensing electrode Rx28 has a sensing capacitance value of 210 at the first time t1 and a sensing capacitance value of -4 at the second time t2. Wherein, the sensing electrode Rx23 has a sensing capacitance change of 222 between the first time t1 and the second time t2, which is less than the preset value, so the touch control circuit 30 identifies the touch object corresponding to the position of the sensing electrode Rx23 as a non-ground conductor. Similarly, the touch control circuit 30 identifies the touch object corresponding to the positions of the sensing electrodes Rx24-Rx28 as a ground conductor.

[0061] In other embodiments, the touch control circuit 30 can also provide a third driving signal DR3 to each of the driving electrodes Tx1-Txm at the first time t1 and receive the sensing signals generated by each of the sensing electrodes Rx1-Rxn. The third driving signal DR3 received by each of the driving electrodes Tx1-Txm is a same-phase pulse signal. The touch control circuit 30 provides the first driving signal DR1 to a part of the driving electrodes Tx1-Txm and provides the second driving signal DR2 to another part of the driving electrodes Tx1-Txm at the second time t2, and receives the sensing signals S1-Sn generated by each of the sensing electrodes Rx1-Rxn.

[0062] In another embodiment, the touch sensing stage T1 further comprises at least one third time t3 and at least one fourth time t4. The touch sensing control circuit 30 sequentially passes through the first to the fourth time t1-t4. At the third time t3 and the fourth time t4, the first electrodes 121_1-121_m serve as the sensing electrodes Rx1-Rxm and the second electrodes 123_1-123_n serve as the driving electrodes Tx1-Txn. At the third time t3, the touch sensing control circuit 30 repeatedly performs the operation of the first time t1 as described above; at the fourth time t4, the touch sensing control circuit 30 repeatedly performs the operation of the second time t2, which will not be repeated here. The touch sensing control circuit 30 further identifies the positions of the sensing electrodes Rxi corresponding to the grounded conductor in the first dimension according to the positions of the sensing electrodes Rxi corresponding to the grounded conductor identified at the first time t1 and the second time t2, and identifies the positions of the sensing electrodes Rxk corresponding to the grounded conductor in the second dimension according to the positions of the sensing electrodes Rxk corresponding to the grounded conductor identified at the third time t3 and the fourth time t4. Thus, the two-dimensional position of the grounded conductor on the capacitive touch sensing device 1 is located.

[0063] The capacitive touch sensing device 1 described above provides a non-coherent driving signal to the driving electrodes at one time in the touch sensing stage T1 and provides a coherent driving signal to each of the driving electrodes at another time in the touch sensing stage T1, compares the change in the sensing capacitance received by the same sensing electrode at the two different times, identifies a non-grounded conductor when the change in the sensing capacitance is small, excludes the false sensing caused by the non-grounded conductor, and thus avoids false sensing of the capacitive touch sensing device 1, thereby improving the accuracy of touch detection of the capacitive touch sensing device 1.

[0064] Please refer to Figure 6 which is a flowchart of a touch sensing method. In at least one embodiment of the present application, the touch sensing method is applied to the capacitive touch sensing device 1. The touch sensing method comprises the following steps:

[0065] Step S600, the first electrodes 121_1-121_m are set as the driving electrodes Tx1-Txm and the second electrodes 123_1-123_n are set as the sensing electrodes Rx1-Rxn.

[0066] Step S601, a first driving signal DR1 is provided to a part of the driving electrodes Tx1-Txm and a second driving signal DR2 is provided to another part of the driving electrodes Tx1-Txm at a first time t1, and the sensing capacitances S1-Sn generated by each of the sensing electrodes Rx1-Rxn are received.

[0067] The first driving signal DR1 and the second driving signal DR2 are non-identical phase pulse signals. In at least one embodiment of the present application, the non-identical phase pulse signal is a pulse signal with at least one of frequency, amplitude and phase different from each other; and the identical phase pulse signal is a pulse signal with all of frequency, amplitude and phase identical to each other. It is understood that the amplitude and phase of the identical phase pulse signal can have slight deviation due to signal loss or other reasons, but the frequency of the identical phase pulse signal must be consistent. Figure 3 For example, the first driving signal DR1 and the second driving signal DR2 are different in frequency, amplitude or phase.

[0068] In at least one embodiment of the present application, at the first time t1, the touch sensing control circuit 30 provides the first driving signal DR1 to the odd-numbered electrodes among the driving electrodes Tx1-Txm and provides the second driving signal DR2 to the even-numbered electrodes among the driving electrodes Tx1-Txm. In other embodiments, at the first time t1, the touch sensing control circuit 30 can also provide the first driving signal DR1 or the second driving signal DR2 to the driving electrodes Tx1-Txm at specific positions. For example, at the first time t1, the touch sensing control circuit 30 can provide the first driving signal DR1 to the driving electrodes Tx2-Tx(m-1) at the center of the touch display area 101 and provide the second driving signal DR2 to the driving electrodes Tx1 and Txm at the edges of the touch display area 101.

[0069] In at least one embodiment of the present application, at the first time t1, the touch sensing control circuit 30 simultaneously receives the sensing capacitances S1-Sn generated by each of the sensing electrodes Rx1-Rxn. In this mode, the capacitive touch sensing device 1 has higher cost but faster signal sensing efficiency. In other embodiments, the touch sensing control circuit 30 can also receive the sensing capacitances S1-Sn generated by each of the sensing electrodes Rx1-Rxn in time division. For example, at the first time t1, the touch sensing control circuit 30 receives the sensing capacitances S1-Si generated by the sensing electrodes Rx1-Rxi, and receives the sensing capacitances (i+1)-Sn generated by the sensing electrodes Rx(i+1)-Rxn at other time between the first time t1 and the second time t2. Wherein i is a positive integer greater than 1 and less than n. In this mode, the capacitive touch sensing device 1 has lower cost but slower signal sensing efficiency.

[0070] Step S602, providing a third driving signal DR3 to each of the driving electrodes Tx1-Txm at a second time t2, and receiving a sensing capacitance generated by each of the sensing electrodes Rx1-Rxn.

[0071] The third driving signal DR3 received by each of the driving electrodes Tx1-Txm is a same-phase pulse signal. In at least one embodiment of the present application, the third driving signal DR3 can be a same-phase signal as the first driving signal DR1. In other embodiments, the third driving signal DR3 can also be a same-phase signal as the second driving signal DR2. Alternatively, the third driving signal DR3 can also be another driving signal different from the first driving signal DR1 and the second driving signal DR2.

[0072] Step S603, calculating a capacitance change of the sensing capacitance Si_t1 sensed by the same sensing electrode Rxi at the first time t1 and the sensing capacitance Si_t2 sensed by the same sensing electrode Rxi at the second time t2.

[0073] Step S604, judging whether the capacitance change is greater than or equal to a preset value.

[0074] Step S605, when the capacitance change is greater than or equal to the preset value, the touch sensing control circuit 30 identifies the touch object corresponding to the position of the sensing electrode Rxi as a grounded conductor.

[0075] Step S606, when the capacitance change is less than the preset value, the touch sensing control circuit 30 identifies the touch object corresponding to the position of the sensing electrode Rxi as a non-grounded conductor.

[0076] Please refer to Figure 7 which is a flowchart of the touch sensing method. The touch sensing method can further include the following steps:

[0077] S607, setting the second electrodes 123_1-123_n as the driving electrodes Tx1-Txn, and setting the first electrodes 121_1-121_m as the sensing electrodes Rx1-Rxm.

[0078] S608, providing the first driving signal DR1 to a part of the driving electrodes Tx1-Txn and providing the second driving signal DR2 to another part of the driving electrodes Tx1-Txn at a third time t3, and receiving a sensing capacitance S1-Sm generated by each of the sensing electrodes Rx1-Rxm.

[0079] S609, providing a third driving signal DR3 to each of the driving electrodes Tx1-Txn at a fourth time t3, and receiving a sensing capacitance generated by each of the sensing electrodes Rx1-Rxm.

[0080] In at least one embodiment of the present application, the touch sensing control circuit 30 sequentially passes through the first to the fourth time t1-t4.

[0081] S610, calculating a capacitance variation of the sensing capacitance Sk_t3 sensed by the same sensing electrode Rxk at the third time t3 and the sensing capacitance Sk_t4 sensed by the same sensing electrode Rxk at the fourth time t4.

[0082] In at least one embodiment of the present application, k is a positive integer greater than 1 and less than m.

[0083] S611, judging whether the capacitance variation is greater than or equal to the preset value.

[0084] S612, when the capacitance variation is greater than or equal to the preset value, the touch sensing control circuit 30 identifies the touch object corresponding to the position of the sensing electrode Rxk as a grounded conductor.

[0085] S613, when the capacitance variation is less than the preset value, the touch sensing control circuit 30 identifies the touch object corresponding to the position of the sensing electrode Rxk as a non-grounded conductor.

[0086] S614, positioning a two-dimensional position of a grounded conductor on the capacitive touch sensing device 1 according to the position of the sensing electrode Rxi corresponding to the grounded conductor identified at the first time t1 and the second time t2 and the position of the sensing electrode Rxk corresponding to the grounded conductor identified at the third time t3 and the fourth time t4.

[0087] The above-mentioned touch sensing method provides a non-coherent driving signal to the driving electrodes at one time in the touch sensing stage T1, and provides a coherent driving signal to each of the driving electrodes at another time in the touch sensing stage T1, compares the variation degree of the sensing capacitance received by the same sensing electrode at two different times, identifies a non-grounded conductor when the variation degree of the sensing capacitance is small, eliminates the false sensing generated by the non-grounded conductor, and further avoids the capacitive touch sensing device 1 from generating false sensing, so as to improve the accuracy of touch detection of the capacitive touch sensing device 1.

[0088] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalent ones; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A capacitive touch sensing device, comprising a touch panel and a touch sensing control circuit; the touch panel comprises a cover plate and a touch electrode layer which are sequentially stacked from top to bottom; the touch electrode layer is patterned to form a plurality of first electrodes extending along a first direction and a plurality of second electrodes extending along a second direction; the touch sensing control circuit is electrically connected with the first electrodes and the second electrodes; characterized in that: The touch sensing stage comprises at least one first time point and at least one second time point; in the first time point and the second time point, the first electrode is used as a driving electrode and the second electrode is used as a sensing electrode; In the first time point, the touch sensing control circuit provides a first driving signal to a part of the driving electrodes and a second driving signal to another part of the driving electrodes, and receives a sensing capacitance generated by each sensing electrode; wherein the first driving signal and the second driving signal are non-coherent pulse signals; in the second time point, the touch sensing control circuit provides a third driving signal to each driving electrode, and receives a sensing capacitance generated by each sensing electrode; the third driving signal received by each driving electrode is a coherent pulse signal; the touch sensing control circuit further calculates a capacitance change of the sensing capacitance sensed by a same sensing electrode in the first time point and the sensing capacitance sensed by the same sensing electrode in the second time point, and compares the capacitance change with a preset value; when the capacitance change is greater than or equal to the preset value, the touch sensing control circuit identifies that a touch object corresponding to the sensing electrode is a grounded conductor; when the capacitance change is less than the preset value, the touch sensing control circuit identifies that the touch object corresponding to the sensing electrode is a non-grounded conductor; the non-coherent pulse signal is a pulse signal with at least one of frequency, amplitude and phase different; the coherent pulse signal is a pulse signal with frequency, amplitude and phase all the same.

2. The capacitive touch sensing device of claim 1, wherein, The touch sensing stage further comprises at least one third time point and at least one fourth time point; the touch sensing control circuit sequentially passes through the first time point to the fourth time point; in the third time point and the fourth time point, the first electrode is used as the sensing electrode and the second electrode is used as the driving electrode; In the third time point, the touch sensing control circuit provides a first driving signal to a part of the driving electrodes and a second driving signal to another part of the driving electrodes, and receives a sensing capacitance generated by each sensing electrode; In the fourth time point, the touch sensing control circuit provides a third driving signal to each driving electrode; The touch sensing control circuit further calculates a capacitance change of the sensing capacitance sensed by a same sensing electrode in the third time point and the sensing capacitance sensed by the same sensing electrode in the fourth time point, and compares the capacitance change with a preset value; when the capacitance change is greater than or equal to the preset value, the touch sensing control circuit identifies that a touch object corresponding to the sensing electrode is a grounded conductor; when the capacitance change is less than the preset value, the touch sensing control circuit identifies that the touch object corresponding to the sensing electrode is a non-grounded conductor; The touch sensing control circuit further locates a two-dimensional position of a grounded conductor on the capacitive touch sensing device according to positions of the sensing electrodes corresponding to the grounded conductor identified in the first time point and the second time point and positions of the sensing electrodes corresponding to the grounded conductor identified in the third time point and the fourth time point.

3. The capacitive touch sensing device of claim 1, wherein, At the first time, the touch control sensing control circuit provides the first driving signal to odd-numbered electrodes among the driving electrodes and provides the second driving signal to even-numbered electrodes among the driving electrodes.

4. The capacitive touch sensing device of claim 1, wherein, At the first time, the touch control sensing control circuit provides the first driving signal to the driving electrodes located in the middle of the touch display area and provides the second driving signal to the driving electrodes located at the edges of the touch display area. 5.The capacitive touch sensing device of claim 1, wherein, At the first time or the second time, the touch control sensing control circuit receives the sensing capacitance generated by the sensing electrodes in time division. 6.A touch sensing method applied to a capacitive touch sensing device, the capacitive touch sensing device comprising a touch panel and a touch sensing control circuit; the touch panel comprising a cover plate and a touch electrode layer stacked in sequence from top to bottom; the touch electrode layer is patterned to form a plurality of first electrodes extending along a first direction and a plurality of second electrodes extending along a second direction; wherein, At any time during the touch sensing stage, one of the first electrode and the second electrode is the driving electrode and the other is the sensing electrode. The touch control sensing control circuit is electrically connected with the first electrode and the second electrode; the touch control sensing method comprises: The first electrode is set as the driving electrode and the second electrode is set as the sensing electrode; At the first time, the first driving signal is provided to a part of the driving electrodes and the second driving signal is provided to another part of the driving electrodes, and the sensing capacitance generated by each sensing electrode is received; wherein the first driving signal and the second driving signal are non-coherent pulse signals. At the second time, the third driving signal is provided to each driving electrode, and the sensing capacitance generated by each sensing electrode is received; the third driving signal received by each driving electrode is a coherent pulse signal. The capacitance change of the same sensing electrode sensing the sensing capacitance at the first time and the sensing capacitance at the second time is calculated. It is judged whether the capacitance change is greater than or equal to a preset value. When the capacitance change is less than the preset value, the touch object corresponding to the position of the sensing electrode is identified as a non-ground conductor. When the capacitance change is greater than or equal to the preset value, the touch object corresponding to the position of the sensing electrode is identified as a ground conductor. The non-coherent pulse signal is a pulse signal with at least one of frequency, amplitude and phase different; the coherent pulse signal is a pulse signal with frequency, amplitude and phase all the same. 7.The touch sensing method of claim 6, wherein, The touch control sensing method further comprises: The second electrode is set as the driving electrode and the first electrode is set as the sensing electrode. At the third time, the first driving signal is provided to a part of the driving electrodes and the second driving signal is provided to another part of the driving electrodes, and the sensing capacitance generated by each sensing electrode is received. At the fourth time, the third driving signal is provided to each driving electrode, and the sensing capacitance generated by each sensing electrode is received. The capacitance change of the same sensing electrode sensing the sensing capacitance at the third time and the sensing capacitance at the fourth time is calculated. It is judged whether the capacitance change is greater than or equal to the preset value. When the capacitance change is less than the preset value, the touch object corresponding to the position of the sensing electrode is identified as a non-ground conductor. When the capacitance change is greater than or equal to the preset value, the touch object corresponding to the sensing electrode position is identified as a ground conductor; According to the positions of the sensing electrodes corresponding to the ground conductors identified at the first and second time instants and the positions of the sensing electrodes corresponding to the ground conductors identified at the third and fourth time instants, a two-dimensional position of the ground conductor on the capacitive touch sensing device is located. 8.The touch sensing method of claim 6, wherein, At the first time instant, the first driving signal is provided to odd-numbered electrodes among the driving electrodes, and the second driving signal is provided to even-numbered electrodes among the driving electrodes. 9.The touch sensing method of claim 6, wherein, At the first time instant, the first driving signal and the second driving signal are respectively provided to the driving electrodes located in the middle of the touch display area; the driving electrodes located at the edges of the touch display area do not receive the first driving signal or the second driving signal. 10.The touch sensing method of claim 6, wherein, At the first time instant or the second time instant, the touch sensing control circuit receives the sensing capacitance generated by the sensing electrodes in time division.

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