Touch detection device, touch screen, electronic device and touch system

Abstract

The present application provides a touch detection device connected to an electrode in a touch screen, the touch detection device comprising: a control module for controlling a short circuit between a first end and a second end of the electrode to generate a capacitance signal on the electrode when the target touches the touch screen, and for controlling the electrode to form a coil loop to generate a current signal on the coil loop when the target outputs an electromagnetic signal to the touch screen; and a detection module for detecting the capacitance signal and the current signal. The touch detection device can simultaneously realize touch detection of the touch screen to a finger and an electromagnetic pen without increasing much cost.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of touch control technology, and more specifically, to a touch detection device, a touch screen, an electronic device, and a touch control system. Background Art

[0002] The current touch screen supports finger touch operation, but the finger operation accuracy and resolution are low, and only some rough touch operations can be completed. The touch operation of the stylus on the touch screen can obtain better accuracy and resolution, thereby realizing some complex touch operations, such as painting, text editing, annotation, etc. The stylus includes capacitive active pens and electromagnetic pens. Since the electromagnetic pen works passively, its core component does not need power supply, and its size is small, which is convenient to carry together with the electronic device as a whole, and can bring better operation accuracy and user experience. Therefore, in addition to supporting finger touch operation, the current touch screen must also be compatible with the touch operation of the electromagnetic pen.

[0003] In order to support the use of electromagnetic pens, the touch screen includes not only the original capacitive detection system to detect the touch operation of the finger, but also the electromagnetic resonance system to detect the touch operation of the electromagnetic pen. These two independent detection systems significantly increase the cost of the touch screen. Therefore, how to realize the touch screen's touch detection of both fingers and electromagnetic pens at a lower cost has become a problem that needs to be solved. Summary of the invention

[0004] The embodiments of the present application provide a touch detection device, a touch screen, an electronic device and a touch system, which can simultaneously realize touch detection of a finger and an electromagnetic pen by the touch screen without increasing much cost.

[0005] In a first aspect, a touch detection device is provided, which is connected to electrodes in a touch screen, and the touch detection device includes:

[0006] a control module, configured to control a short circuit between the first end and the second end of the electrode so as to generate a capacitance signal on the electrode when the target touches the touch screen, and to control the electrode to form a coil loop so as to generate a current signal on the coil loop when the target outputs an electromagnetic signal to the touch screen; and

[0007] The detection module is used to detect the capacitance signal and the current signal.

[0008] In an embodiment of the present application, the touch detection device controls the connection mode of the first end and the second end of the electrode in the touch screen, and detects the signal on the electrode under different connection modes. When the control module controls the two ends of the electrode to be short-circuited, the detection module can detect the capacitive signal caused by the target touch on the electrode, thereby realizing the detection of the capacitive signal of the target; when the control module controls the electrode to form a coil loop, the detection module can detect the current signal induced on the loop by the electromagnetic signal output by the target on the electrode, thereby realizing the detection of the electromagnetic signal of the target. Since the same electrode is used to perform capacitive detection and electromagnetic detection on the target, no additional cost is required.

[0009] In a possible implementation manner, the touch detection device further includes: a driving module, configured to output a driving signal to the electrode.

[0010] In one possible implementation, the control module is specifically used to: in a first time period, control the first end and the second end of the electrode to be simultaneously connected to the output end of the driving module so that the driving module outputs a driving signal to the electrode; and / or control the first end and the second end of the electrode to be simultaneously connected to the first input end of the detection module so that the detection module detects the capacitance signal.

[0011] In a possible implementation, the control module is also used to: in a second time period, control the first end of the electrode to be connected to the output end of the driving module, the second end of the electrode to be connected to a common port, and the first end of the electrode to be disconnected from the detection module, so that the driving module outputs a driving signal to the coil loop; and control the first end of the electrode to be connected to the first input end of the detection module, and the second end of the electrode to be connected to the common port, so that the detection module detects the current signal.

[0012] In a possible implementation, a first switch is provided between the second end of the electrode, the driving module and the common port, and the first switch is used to connect the second end of the electrode and the driving module in the first time period, and to connect the second end of the electrode and the common port in the second time period; a second switch is provided between the detection module and the first end of the electrode, and the second switch is used to control the connection and disconnection between the electrode and the detection module in the second time period.

[0013] Alternatively, in another possible implementation, a third switch is provided between the second end of the electrode and the driving module, and the third switch is used to connect the second end of the electrode and the driving module in the first time period; a fourth switch is provided between the second end of the electrode and the common port, and the fourth switch is used to connect the second end of the electrode and the common port in the second time period; a second switch is provided between the detection module and the first end of the electrode, and the second switch is used to control the connection and disconnection between the electrode and the detection module in the second time period.

[0014] Further, in a possible implementation manner, a fifth switch is provided between the first end of the electrode and the driving module, and the fifth switch is used to connect the first end of the electrode and the driving module in the first time period and the second time period.

[0015] In this way, switches are set on the first end, the second end, the driving module and the detection module of the electrode on some lines, and each line is turned on and off by controlling each switch, so that the two ends of the electrode are short-circuited in the first period, and the two ends of the electrode are connected to different potentials in the second period to form a coil loop.

[0016] In a possible implementation manner, the common port is a system ground of the touch screen; or, the common port is a port with a preset level.

[0017] In one possible implementation, the second end of the electrode is connected to the common port, including: the second end of the electrode is directly connected to the common port through a switch; or the second end of the electrode is connected to the common port after being connected in series with at least one other electrode arranged in the same direction through a switch to form the coil loop composed of the electrode and at least one other electrode.

[0018] Since the control module controls multiple electrodes to be connected in series to form a larger coil loop, when a target such as an electromagnetic pen outputs an electromagnetic signal to the coil loop, a stronger current signal can be induced on the coil loop, thereby improving the performance of touch detection.

[0019] In one possible implementation, the detection module includes a single-ended amplifier and a detection resistor, the detection resistor is located between a first input terminal and an output terminal of the single-ended amplifier or between a first input terminal and a second input terminal of the single-ended amplifier, the first input terminal is used to connect to the first end of the electrode, and the second input terminal is used to connect to a common port.

[0020] In one possible implementation, the detection module includes a differential amplifier, and detection resistors are provided between the first input terminal and the first output terminal and between the second input terminal and the second output terminal of the differential amplifier, or a detection resistor is provided between the first input terminal and the second input terminal of the differential amplifier, the first input terminal is used to connect the first end of the electrode, and the second input terminal is used to connect the common port.

[0021] In a possible implementation, the touch detection device further includes a filtering module, and the filtering module is used to perform low-pass filtering on the signal output by the detection module in the first time period, and perform band-pass filtering on the signal output by the detection module in the second time period.

[0022] In a possible implementation, the electrode includes two oppositely disposed segments, the first end and the second end, one end of the two segments located on the same side is connected, and the other ends of the two segments respectively form the first end and the second end.

[0023] In a second aspect, a touch screen is provided, comprising the touch detection device in the first aspect or any possible implementation of the first aspect, and a plurality of electrodes connected to the touch detection device.

[0024] In a third aspect, an electronic device is provided, comprising the touch screen in the second aspect or any possible implementation of the second aspect.

[0025] In a fourth aspect, a touch control system is provided, comprising the touch screen in the third aspect or any possible implementation of the third aspect, and an electromagnetic pen. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of a touch screen.

[0027] Figure 2 Schematic diagram of a touch screen applicable to the touch detection device of the embodiment of the present application.

[0028] Figure 3 It is a schematic diagram of an electromagnetic pen.

[0029] Figure 4 is a schematic block diagram of a touch detection device according to an embodiment of the present application.

[0030] Figure 5 It is a schematic diagram of the detection sequence of the touch detection device.

[0031] Figure 6 It is a schematic diagram of mutual capacitance detection.

[0032] Figure 7 It is a schematic diagram of self-capacitance detection.

[0033] Figure 8 It is a schematic diagram of electromagnetic signal detection.

[0034] Fig. 9 It is a schematic diagram of electromagnetic signal detection.

[0035] Fig.10 It is a schematic diagram of a detection module according to an embodiment of the present application.

[0036] Fig.11 It is a schematic diagram of a detection module according to an embodiment of the present application.

[0037] Fig.12 It is a schematic diagram of a detection module according to an embodiment of the present application.

[0038] Fig.13 It is a schematic diagram of a detection module according to an embodiment of the present application.

[0039] Fig.14 It is a schematic diagram of a specific implementation method of the touch detection device.

[0040] Fig.15 It is a schematic block diagram of a touch screen according to an embodiment of the present application. DETAILED DESCRIPTION

[0041] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0042] Mobile devices currently on the market, such as smartphones, tablets, and laptops, all have a rich display screen human-computer interaction interface. From a functional point of view, some electronic devices only support finger operations, while some electronic devices support both finger operations and stylus (hereinafter referred to as "pen"). From a technical point of view, the touch screens of electronic devices are basically integrated with capacitance detection technology, which supports both finger operations and capacitance pen operations; in addition to integrating capacitance detection technology, some other electronic devices also integrate electromagnetic resonance technology to support electromagnetic pen operations. From the perspective of human-computer interaction experience, when a finger operates on the touch screen, the coordinate accuracy of the finger position is low, and generally only some rough operations can be performed; while the coordinate control accuracy of the pen is higher, and some special operations can be achieved, such as painting, text editing, annotation, etc. The pen includes a capacitive active pen (abbreviated as active pen or capacitive pen) and an electromagnetic resonance pen (abbreviated as electromagnetic pen). Among them, the electromagnetic pen works passively, its core component does not require power supply, is small in size, and is easy to carry with the electronic device as a whole, and can bring better operation accuracy and user experience. Therefore, in addition to supporting touch operations of fingers and capacitive pens, the current touch screen must also be compatible with touch operations of electromagnetic pens. In terms of cost, current touch screens can all realize capacitance detection. If an electronic device needs to support the function of a capacitance pen, the increase in cost mainly comes from the capacitance pen, so the cost of the capacitance pen is higher than that of the electromagnetic pen. If an electronic device needs to support the function of an electromagnetic pen, in addition to integrating the capacitance detection function, the touch screen also needs to separately add sensors and controllers that support electromagnetic resonance technology, such as Figure 1 As shown, the touch screen 10 includes a capacitive touch panel 110 , a display panel 120 , and an electromagnetic induction (EMR) panel 130 . The two independent systems of the capacitive touch panel 110 and the EMR panel 130 significantly increase the cost of the touch screen 10 .

[0043] To this end, the present application provides a touch screen that can simultaneously detect touches of fingers and electromagnetic pens without increasing much cost.

[0044] Figure 2 Schematic diagram of a touch screen of a touch detection device applicable to an embodiment of the present application. Figure 2 As shown, a plurality of sensors, hereinafter also referred to as electrodes or channels, are arranged in the touch screen 10. The plurality of electrodes in the touch screen 10 are arranged in rows and columns in an alternating manner, wherein the number of transverse electrodes and the number of longitudinal electrodes can be set based on the size of the touch screen 10 and the requirements of touch detection, for example, forming an electrode array of 20 rows×40 columns, or an electrode array of 40 rows×40 columns. Figure 2Only a small number of electrodes are shown to illustrate the technical solution of the present application, wherein TX1, TX2, and TX3 are horizontal electrodes, and RX1, RX2, and RX3 are vertical electrodes. In the embodiment of the present application, the horizontal electrodes are driving electrodes, and the vertical electrodes are sensing electrodes or receiving electrodes.

[0045] Figure 2 As an example, each electrode is a strip electrode, which is bent into two parallel sections, and the ends of the two sections opposite to the bend respectively form the first end and the second end of the electrode. Taking electrode TX1 as an example, the first end and the second end of electrode TX1 are TX1-a and TX1-b respectively. The first end and the second end of each electrode are used to connect to the touch detection device in the embodiment of the present application, and the touch detection device can control the connection method of the first end and the second end of the electrode, so as to realize capacitive detection and electromagnetic detection of the target. Figure 2 In the embodiment, the transverse electrodes and the longitudinal electrodes are located in different stacking layers.

[0046] Figure 3 (a) shows an electromagnetic pen, which can be equivalent to Figure 3 In addition, in order to enrich the functions of the electromagnetic pen, its equivalent circuit may also have other devices such as switches, etc. Figure 3 Not shown.

[0047] Figure 4 is a schematic block diagram of a touch detection device according to an embodiment of the present application. The touch detection device 400 is connected to electrodes in the touch screen, which electrodes may be Figure 2 The electrode shown has two oppositely arranged segments, a first end and a second end. One ends of the two segments located on the same side are connected, and the other ends of the two segments form the first end and the second end of the electrode respectively.

[0048] When the first end and the second end are short-circuited, the electrode is used to detect the capacitive signal when the target touches the touch screen; when the two segments, the first end and the second end form a coil loop, the electrode is used to detect the electromagnetic signal output by the target to the touch screen.

[0049] by Figure 2 Taking the electrode TX1 in the example, when the electrode TX1 is used to detect the capacitance signal, the touch detection device 400 controls the first end TX1-a and the second end TX-b of the electrode TX1 to be short-circuited so that the two segments of the electrode form a whole. A coil loop in which current can flow cannot be generated inside the electrode, and therefore the electrode will not be affected by the electromagnetic signal.

[0050] When the electrode TX1 is used to detect electromagnetic signals, the electrode needs to form a coil loop that can carry current signals to induce current signals according to the received electromagnetic signals. At this time, there needs to be a potential difference between the first end and the second end of the electrode. At this time, the touch detection device 400 can control the first end TX1-a and the second end TX-b of the electrode TX1 to be connected to different potentials respectively, so that the electrode can be used as part of the coil loop to carry current signals. When the drive signal is input to the coil loop, a current is generated in the coil loop, and then a magnetic field is induced to transmit electromagnetic signals. If there is an electromagnetic pen above the touch screen, the LC oscillation circuit in the electromagnetic pen starts to oscillate after the electromagnetic pen receives the electromagnetic signal emitted by the electrode. When the electrode stops emitting electromagnetic signals, the LC oscillation circuit in the electromagnetic pen still keeps oscillating and outputs electromagnetic signals in the opposite direction to the touch screen. At this time, the coil loop formed by the electrode can sense the electromagnetic signal output by the electromagnetic pen. According to the strength of the electromagnetic signals sensed in different directions, the position of the tip of the electromagnetic pen can be determined.

[0051] It should be understood that in the embodiment of the present application, the electrode forms a coil loop, which may mean that the coil loop includes the electrode, that is, includes two segments of the electrode, the first end and the second end; it may also mean that the electrode is a part of the coil loop, that is, the coil loop may also have other conductors.

[0052] like Figure 4 As shown, the touch detection device 400 includes a control module 410 and a detection module 420 .

[0053] Among them, the control module 410 is used to control the short circuit between the first end and the second end of the electrode to generate a capacitive signal on the electrode when the target touches the touch screen; and to control the electrode to form a coil loop to generate a current signal on the coil loop when the target outputs an electromagnetic signal to the touch screen.

[0054] The detection module 420 is used to detect the capacitance signal and the current signal.

[0055] It should be understood that the target touching the touch screen includes directly contacting the touch screen and approaching the touch screen. The target may be, for example, a finger, an electromagnetic pen, etc.

[0056] In this embodiment, the touch detection device 400 controls the connection mode of the first end and the second end of the electrode in the touch screen, and detects the signal on the electrode under different connection modes. When the control module 410 controls the two ends of the electrode to be short-circuited, the detection module 420 can detect the capacitive signal caused by the target touch on the electrode, thereby realizing the capacitive detection of the target; when the control module 410 controls the electrode to form a coil loop, the detection module 420 can detect the current signal induced on the loop by the electromagnetic signal output by the target on the electrode, thereby realizing the electromagnetic detection of the target. Since the same electrode is used to perform capacitive detection and electromagnetic detection on the target, no additional cost is required.

[0057] For example Figure 2 As shown, the electrode is a strip electrode, which is bent into two parallel sections, and the ends of the two sections opposite to the bend form the first end and the second end of the electrode respectively. Taking electrode TX1 as an example, the first end and the second end of electrode TX1 are TX1-a and TX1-b respectively.

[0058] Among them, when the electrode is used to detect the capacitance signal when the target touches the touch screen, the first end and the second end of the electrode are short-circuited so that the two segments of the electrode form a whole, and a coil loop in which current can flow cannot be generated inside the electrode, so it will not be affected by the electromagnetic signal to generate a current signal; and when the electrode is used to detect the electromagnetic signal output by the target to the touch screen, the electrode needs to form a coil loop in which current can flow so as to induce a current signal according to the received electromagnetic signal. Therefore, at this time, there needs to be a potential difference between the first end and the second end of the electrode. For example, the first end and the second end can be connected to different potentials respectively, thereby forming a coil loop consisting of the first end, the second end and the two segments.

[0059] Furthermore, the touch detection device 400 may also include a driving module 430, which is used to output a driving signal to the electrode. When detecting a capacitive signal corresponding to a target such as a finger or a capacitive pen, and when detecting an electromagnetic signal corresponding to a target such as an electromagnetic pen, the driving signal output by the driving module 430 may be different, for example, its frequency, amplitude and other parameters may be different.

[0060] Figure 5 FIG. 4 shows the detection timing of the touch detection device 400. The touch detection device 400 detects the capacitive signal and the electromagnetic signal in a time-sharing manner. Figure 5In the detection cycle shown, in the first time period T1, the touch detection device 400 detects the capacitance signal of the target and determines the touch information of the target according to the capacitance signal. In the first time period T1, the touch detection device 400 can perform mutual capacitance detection, that is, detect the mutual capacitance between the two electrodes in the horizontal direction and the vertical direction; it can also perform self-capacitance detection, that is, detect the self-capacitance of each electrode to the ground; or alternately perform self-capacitance detection and mutual capacitance detection, for example Figure 5 As shown, the interval time t3 between the self-capacitance detection and the mutual-capacitance detection can be used for switching the working state.

[0061] In the second time period T2, the touch detection device 400 detects the electromagnetic signal of the target and determines the touch information of the target based on the electromagnetic signal. The first time period T1 and the second time period T2 can be separated by a time interval t4 for switching the working state. The second time period T2 can include a time period of electromagnetic signal driving and a time period of electromagnetic signal reception, and a time interval t5 can be separated by the two time periods for switching the working state. In the time period of electromagnetic signal driving, the driving module 430 outputs a driving signal to the electrode, so that the coil loop of the TX electrode generates and outputs an electromagnetic signal. When there is an electromagnetic pen above the touch screen, the oscillation circuit in the electromagnetic pen can be stimulated to oscillate. When the electrode stops emitting electromagnetic signals, the oscillation circuit in the electromagnetic pen still keeps oscillating and outputs electromagnetic signals in the opposite direction to the touch screen. In the time period of electromagnetic signal reception, the coil loop of the electrode senses the electromagnetic signal and generates a current in the coil loop. The detection module detects the current signal and converts the current signal into a voltage signal for determining the touch information of the target.

[0062] It should be understood that Figure 5 For illustration only, the embodiment of the present application does not limit the sequence and duration of the first time period T1 and the second time period T2.

[0063] In one implementation, a first switch K1 is provided between the second end of the electrode, the driving module 430 and the common port, and the first switch K1 is used to connect the second end of the electrode and the driving module 430 in the first time period T1, and to connect the second end of the electrode and the common port in the second time period T2; a second switch K2 is provided between the detection module 420 and the first end of the electrode, and the second switch K2 is used to control the connection and disconnection between the electrode and the detection module 420 in the second time period T2.

[0064] Alternatively, in another implementation, a third switch K3 is provided between the second end of the electrode and the driving module 430, and the third switch K3 is used to connect the second end of the electrode and the driving module 430 in the first time period T1; a fourth switch K4 is provided between the second end of the electrode and the common port, and the fourth switch is used to connect the second end of the electrode and the common port in the second time period T2; a second switch K2 is provided between the detection module 420 and the first end of the electrode, and the second switch K2 is used to control the connection and disconnection between the electrode and the detection module 420 in the second time period T2.

[0065] Further, in one implementation, a fifth switch K5 is provided between the first end of the electrode and the driving module 430 , and the fifth switch K5 is used to connect the first end of the electrode and the driving module 430 in the first period T1 and the second period T2 .

[0066] In this way, switches are set on the first end, the second end, and part of the circuit between the driving module 430 and the detection module 420 of the electrode, and the conduction and disconnection of each circuit are realized by controlling each switch, so that the two ends of the electrode are short-circuited in the first time period T1, and the two ends of the electrode are connected to different potentials in the second time period T2 to form a coil loop.

[0067] The common port is a fixed potential. For example, the common port may be a system ground GND of the touch screen, or a voltage with a preset voltage level V com In the following, the common port is used as the preset level V com For example, V com For example, it is equal to the power supply voltage V CC , or half of the power supply voltage, V com =V CC / 2.

[0068] In the embodiment of the present application, the control module 410 can control the connection mode between the first end and the second end of the electrode in the following manner, for example.

[0069] In the first time period T1, the control module 410 controls the first end and the second end of the electrode to be simultaneously connected to the output end of the driving module 430 so that the driving module 430 outputs a driving signal to the electrode; and / or controls the first end and the second end of the electrode to be simultaneously connected to the first input end of the detection module 420 so that the detection module 420 detects the capacitance signal when the target touches the touch screen.

[0070] Specifically, the touch detection device 400 detects the capacitive signal and the electromagnetic signal in time division, performs capacitive detection on the target in the first time period T1, and performs electromagnetic signal detection on the target in the second time period T2. In the first time period T1, when performing mutual capacitance detection, the control module 410 controls the first end and the second end of the driving electrode to be simultaneously connected to the output end of the driving module 410, and the driving module 410 outputs the driving signal to each driving electrode in turn, and controls the first end and the second end of each detection electrode to be simultaneously connected to the first input end of the detection module 420, and the detection module 420 detects the mutual capacitance signal between each detection electrode and the driving electrode, and converts the mutual capacitance signal into a voltage signal for determining information such as the touch position of the target.

[0071] For example Figure 6 As shown, when mutual capacitance detection is performed, taking electrode TX1 and electrode RX1 as an example, switches K1 and K5 corresponding to electrode TX1 and electrode RX1 are closed, and the first end TX1-a and the second end TX1-b of electrode TX1 are simultaneously connected to the driving module 430, and the first end RX1-a and the second end RX1-b of electrode RX1 are simultaneously connected to the detection module 420. The driving module 430 inputs a driving signal for mutual capacitance detection to electrode TX1, and the detection module 420 receives the mutual capacitance signal between electrode TX1 and electrode RX1. When the target touches the touch screen, the mutual capacitance signal between electrode TX1 and electrode RX1 may change, and the relevant touch information can be determined based on the change of the capacitance signal.

[0072] In the first time period T1, when self-capacitance detection is performed, the control module 410 controls the first end and the second end of each electrode to be simultaneously connected to the output end of the driving module 230, and the driving module 430 outputs a driving signal to the electrode, and controls the first end and the second end of the electrode to be simultaneously connected to the first input end of the detection module, and the detection module 420 detects the self-capacitance signal of the electrode to the ground, and converts the self-capacitance signal into a voltage signal for determining information such as the touch position of the target.

[0073] For example Figure 7As shown, when performing self-capacitance detection, taking the electrode TX1 and the electrode RX1 as an example, the switches K1 and K5 corresponding to the electrode TX1 and the electrode RX1 are closed, the first end TX1-a and the second end TX1-b of the electrode TX1 are simultaneously connected to the corresponding driving module 430, and the first end TX1-a and the second end TX1-b of the electrode TX1 are simultaneously connected to the corresponding detection module 420, the driving module 430 inputs a driving signal for self-capacitance detection to the electrode TX1, and the detection module 420 receives the self-capacitance signal of the electrode TX1. Similarly, the first end RX1-a and the second end RX1-b of the electrode RX1 are simultaneously connected to the corresponding driving module 430, and the first end RX1-a and the second end RX1-b of the electrode RX1 are simultaneously connected to the corresponding detection module 420, the driving module 430 inputs a driving signal for self-capacitance detection to the electrode RX1, and the detection module 420 receives the self-capacitance signal of the electrode RX1. When the target touches the touch screen, the self-capacitance of the electrode TX1 and the self-capacitance signal of the electrode RX1 may change, and the relevant touch information may be determined based on the change of the self-capacitance signal of each electrode.

[0074] In the second time period T2, the control module 410 controls the first end of the electrode to be connected to the output end of the driving module 430, the second end of the electrode to be connected to the common port, and the first end of the electrode is disconnected from the detection module 420, so that the driving module 430 outputs a driving signal to the coil loop; then, the first end of the electrode is controlled to be connected to the first input end of the detection module 420, and the second end of the electrode is connected to the common port, so that the detection module 420 detects the current signal in the coil loop.

[0075] Specifically, in the second time period T2, when the touch detection device 400 detects the electromagnetic signal of the target, the control module 410 controls the first end of the TX electrode to be connected to the output end of the driving module 430, and the second end to be connected to the common port, so that the driving electrode forms a coil loop, and the driving module 430 outputs a driving signal to the coil loop. The driving signal generates a current in the coil loop, thereby generating a magnetic field and emitting an electromagnetic signal. If there is an electromagnetic pen above the touch screen, the electromagnetic pen receives the electromagnetic signal and the oscillation circuit inside it starts to oscillate. When the electrode stops emitting the electromagnetic signal, the oscillation circuit still keeps oscillating and outputs the electromagnetic signal in the opposite direction to the touch screen. Then, the control module 410 controls the first end of the driving electrode and the first end of the detection electrode to be connected to the first input end of the corresponding detection module 420, respectively, and the second end is connected to the common port to form a coil loop, through which the electromagnetic signal output by the electromagnetic pen is sensed and a current is generated in the coil loop. The detection module 420 detects the current signal and converts the current signal into a voltage signal for determining information such as the position of the tip of the electromagnetic pen.

[0076] For example Figure 8 As shown, taking electrode TX1 and electrode RX1 as an example, during the period of detecting the electromagnetic signal of the target, the switch K5 corresponding to each electrode is closed, and the switch K1 is closed to position 1. It should be understood that the switch K1 can be a single-pole double-throw switch, which can be connected to position 1 or position 2. Figure 8 As shown, position 1 can be V com , position 2 may be the output terminal of the driving module 430. When the switch K1 is closed to position 1, the second terminal of each electrode and V com When the switch K1 is closed to position 2, the second end of each electrode and the driving module 430 can be connected.

[0077] Taking electrode TX1 as an example, during the period of electromagnetic signal driving, switch K2 is disconnected, and the driving module 430 inputs the driving signal to the first end TX1-a of electrode TX1; during the period of electromagnetic signal reception, switch K2 is closed, and the detection module 420 can detect the current signal generated by the target output electromagnetic signal on electrode TX1.

[0078] Here, the electrode connected to the driving module 430 can be a TX electrode or an RX electrode. Alternatively, both the TX electrode and the RX electrode are connected to the driving module 430. When the driving module 430 is connected, the electrode can be used as a driving electrode to output an electromagnetic signal. Similarly, the electrode connected to the detection module 420 can be a TX electrode or an RX electrode. Alternatively, both the TX electrode and the RX electrode are connected to the detection module 420. When the detection module 420 is connected, the electrode can be used as a detection electrode to induce a corresponding current signal according to the received electromagnetic signal. In the embodiment of the present application, for example Figure 8 As shown, the description is made by taking the TX electrode as the driving electrode and the TX electrode and the RX electrode as the detection electrodes as an example.

[0079] During the period of electromagnetic signal reception, the first end TX1-a of the electrode TX1 is connected to the corresponding detection module 420 through the switch K5, and the second end TX1-b of the electrode TX1 is connected to V com The first end RX1-a of the electrode RX1 is connected to the corresponding detection module 420 through the switch K5, and the second end RX1-b of the electrode RX1 is connected to V through the switch K1. com , so the electrode TX1 and the electrode RX1 each form a coil loop to sense the electromagnetic signal output by the target through the coil loop.

[0080] Figure 8 This is just an example. Instead of using the single-pole double-throw switch K1, a third switch K3 is provided between the second end TX1-b of the electrode TX1 and the driving module 430. comThat is, the switch K1 is replaced by a switch K3 connected between the second end of the electrode and the driving module 430, and a switch K4 connected between the second end of the electrode and V com In the first period T1, the switch K3 is closed to conduct the second end of the electrode and the driving module 430; in the second period T2, the switch K4 is closed to conduct the second end of the electrode and V com .

[0081] The second end of the electrode can be directly connected to V through a switch. com ,For example Figure 8 Alternatively, the second end of the electrode can be connected to V by connecting it in series with at least one other electrode arranged in the same direction through a switch. com , to form a coil loop consisting of the electrode and at least one other electrode. Fig. 9 As shown, the electrodes TX1 and TX2 arranged in the same direction, i.e., horizontally, are connected together through a switch. Specifically, the second end TX1-b of the electrode TX1 is connected to the first end TX2-a of the electrode TX2 through the switch, and the second end TX2-b of the electrode TX2 is connected to V com , electrode TX1 and electrode TX2 together form a larger coil loop. Similarly, electrode RX1 and electrode RX2 can be connected together in the same way to form a larger coil loop. When the target outputs an electromagnetic signal to the coil loop, a stronger current signal can be induced on the coil loop, thereby improving the performance of touch detection. Fig. 9 The combination of two electrodes is taken as an example. In actual applications, more electrodes can be connected to form a larger induction coil.

[0082] In the embodiment of the present application, the detection module 420 may have, for example, Figures 10 to 13 Several forms are shown in . Figures 10 to 13 In the figure, when the transverse electrodes and the longitudinal electrodes are used to form a coil loop to sense the electromagnetic signal output by the target, L and Rs represent the inductance and impedance of the coil loop, respectively.

[0083] like Fig.10 As shown, the detection module 420 includes a single-ended amplifier 421 and a detection resistor Rf, and the detection resistor Rf is located between the first input terminal and the output terminal Vout of the single-ended amplifier 421. The first input terminal is used to connect the first end of the electrode, and the second input terminal of the single-ended amplifier 421 is used to connect the common port V com Here, it is taken as an example that the first input terminal and the second input terminal are respectively a negative input terminal and a positive input terminal.

[0084] like Fig.11As shown, the detection module 420 includes a single-ended amplifier 421 and a detection resistor Zi, and the detection resistor Zi is located between the first input terminal and the second input terminal of the single-ended amplifier 421. The first input terminal is used to connect the first end of the electrode, and the second input terminal is connected to the common port V com Here, it is taken as an example that the first input terminal and the second input terminal are respectively a positive input terminal and a negative input terminal.

[0085] like Fig.12 As shown, the detection module 420 includes a differential amplifier 422, a detection resistor Rf1 and a detection resistor Rf2, wherein the detection resistor Rf1 is located between the first input terminal and the first output terminal Vout- of the single-ended amplifier 421, and the detection resistor Rf2 is located between the second input terminal and the second output terminal Vout+ of the single-ended amplifier 421. The first input terminal is used to connect the first end of the electrode, and the second input terminal is connected to the common port V com Here, it is taken as an example that the first input terminal and the second input terminal are respectively a positive input terminal and a negative input terminal, and the first output terminal and the second output terminal are respectively a negative output terminal and a positive output terminal.

[0086] like Fig.13 As shown, the detection module 420 includes a differential amplifier 422 and a detection resistor Zi, and the detection resistor Zi is located between the first input terminal and the second input terminal of the single-ended amplifier 421. The first input terminal is used to connect the first end of the electrode, and the second input terminal is connected to the common port V com Here, it is taken as an example that the first input terminal and the second input terminal are respectively a positive input terminal and a negative input terminal, and the first output terminal and the second output terminal are respectively a negative output terminal and a positive output terminal.

[0087] In one implementation, the touch detection device 400 further includes a filtering module 440. The filtering module 440 is configured to perform low-pass filtering on the signal output by the detection module 420 in the first period T1, and perform band-pass filtering on the signal output by the detection module 420 in the second period T2.

[0088] Fig.14 FIG. 4 shows a possible specific implementation of the touch detection device 400. Fig.14 As shown, the touch detection device 400 may include a control module 410, a switch module 470, a driving module 430, a detection module 420, a filtering module 440, an analog to digital converter (ADC) 450, a digital demodulation module 460, a data processing module and a control module 410. The switch module 470, for example, includes at least the aforementioned switches K1 to K5.

[0089] When the touch detection device 400 works in the capacitance detection mode, the data processing module and the control module 410 control the driving module 430, the switch module 470, the ADC 450, and the digital demodulation module 460 to work. When performing mutual capacitance and self-capacitance detection, the driving module 430 generates a self-capacitance or mutual capacitance driving signal, which is sent to the TX electrode and the RX electrode through the switch module 470. At the same time, the detection module 420 receives the signal on the electrode and sends it to the subsequent filter module 440. The capacitance detection generally uses a low-pass filter to filter out the interference of high-frequency signals. After being processed by the filter module 440, the signal enters the ADC 450 to convert the analog signal into a digital signal. Then, the digital demodulation module 460 demodulates the same-frequency signal related to the drive and converts it into a DC signal. The change of the DC signal is related to the touch state of the target. The data processing module calculates the touch position of the target on the touch screen, that is, the coordinate information, and finally outputs the coordinate information to the main controller of the electronic device.

[0090] When the touch detection device 400 works in the electromagnetic signal detection mode, the data processing module and the control module 410 control the driving module 430, the switch module 470, the ADC450, and the digital demodulation module 460 to work. When detecting electromagnetic signals, the driving module 430 generates an AC driving signal, which is sent to the TX electrode through the switch module 470. If there is an electromagnetic pen above the touch screen, the electromagnetic pen will generate a resonant signal after a period of driving, and then the control module 410 controls the driving module 410 to turn off, and controls the switch module 470 to put the TX electrode and the RX electrode in a receiving state to receive the electromagnetic signal fed back from the electromagnetic pen. At the same time, the detection module detects the electromagnetic signal on the electrode and sends it to the subsequent filter module 440. The electromagnetic signal detection generally uses a bandpass filter to filter out the interference of out-of-band signals. The signal is processed by the filter module 440 and enters the ADC 450 to convert the analog signal into a digital signal. Next, the digital demodulation module 460 demodulates the driving-related co-frequency signal and converts it into a DC signal. The change of the DC signal is related to the touch state of the electromagnetic pen. The data processing module calculates the touch position of the electromagnetic pen on the touch display screen, that is, the coordinate information, and other control states such as whether the button on the electromagnetic pen is pressed, etc. Finally, the coordinate information and control state information of the electromagnetic pen are output to the main controller of the electronic device.

[0091] like Fig.15 As shown, the present application further provides a touch screen 1500, including the aforementioned touch detection device 400, and a plurality of electrodes 500 connected to the touch detection device 400, wherein the plurality of electrodes 500 include the aforementioned TX electrodes and RX electrodes.

[0092] The present application also provides an electronic device, including a touch screen 1500 .

[0093] The present application also provides a touch control system, including a touch control screen 1500 and an electromagnetic pen.

[0094] It should be noted that, under the premise of no conflict, the various embodiments described in this application and / or the technical features in each embodiment can be arbitrarily combined with each other, and the technical solution obtained after the combination should also fall within the protection scope of this application.

[0095] The systems, devices and methods disclosed in the embodiments of the present application may be implemented in other ways. For example, some features of the method embodiments described above may be ignored or not performed. The device embodiments described above are merely schematic, and the division of units is merely a logical function division. There may be other division methods in actual implementation, and multiple units or components may be combined or integrated into another system. In addition, the coupling between the units or the coupling between the components may be direct coupling or indirect coupling, and the coupling may include electrical, mechanical or other forms of connection.

[0096] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described devices and equipment and the technical effects produced can refer to the corresponding processes and technical effects in the aforementioned method embodiments, and will not be repeated here.

[0097] It should be understood that the specific examples in the embodiments of the present application are only to help those skilled in the art to better understand the embodiments of the present application, rather than to limit the scope of the embodiments of the present application. Those skilled in the art can make various improvements and modifications based on the above embodiments, and these improvements or modifications all fall within the scope of protection of the present application.

[0098] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A touch detection device, characterized in that: Connected to the electrodes in the touch screen, the touch detection device includes: a control module, configured to control the short circuit between the first end and the second end of the electrode to generate a capacitance signal on the electrode when the target touches the touch screen, and to control the electrode to form a coil loop to generate a current signal on the coil loop when the target outputs an electromagnetic signal to the touch screen; and A detection module, used to detect the capacitance signal and the current signal; A driving module, used for outputting a driving signal to the electrode; The control module is specifically used for: In a first time period, the first end and the second end of the electrode are controlled to be connected to the output end of the driving module at the same time, so that the driving module outputs a driving signal to the electrode; and / or, the first end and the second end of the electrode are controlled to be connected to the first input end of the detection module at the same time, so that the detection module detects the capacitance signal; In the second period, the first end of the electrode is controlled to be connected to the output end of the driving module, the second end of the electrode is connected to the common port, and the first end of the electrode is disconnected from the detection module, so that the driving module outputs a driving signal to the coil loop; and the first end of the electrode is controlled to be connected to the first input end of the detection module, and the second end of the electrode is connected to the common port, so that the detection module detects the current signal; The electrode includes two segments arranged in parallel, the first end and the second end, one end of the two segments located on the same side is connected, and the other ends of the two segments form the first end and the second end respectively.

2. The touch detection device according to claim 1, characterized in that: A first switch is provided between the second end of the electrode, the driving module and the common port, and the first switch is used to connect the second end of the electrode and the driving module in the first period, and to connect the second end of the electrode and the common port in the second period. A second switch is provided between the detection module and the first end of the electrode, and the second switch is used to control the connection and disconnection between the electrode and the detection module during the second period.

3. The touch detection device according to claim 1, characterized in that: A third switch is provided between the second end of the electrode and the driving module, and the third switch is used to connect the second end of the electrode and the driving module during the first period. A fourth switch is provided between the second end of the electrode and the common port, and the fourth switch is used to connect the second end of the electrode and the common port in the second period. A second switch is provided between the detection module and the first end of the electrode, and the second switch is used to control the connection and disconnection between the electrode and the detection module during the second period.

4. The touch detection device according to claim 2 or 3, characterized in that: A fifth switch is provided between the first end of the electrode and the driving module, and the fifth switch is used to connect the first end of the electrode and the driving module in the first time period and the second time period.

5. The touch detection device according to any one of claims 1 to 3, characterized in that: The common port is the system ground of the touch screen; or, The common port is a port with a preset level.

6. The touch detection device according to any one of claims 1 to 3, characterized in that: The second end of the electrode is connected to the common port, comprising: The second end of the electrode is directly connected to the common port through a switch; or, The second end of the electrode is connected in series with at least one other electrode arranged in the same direction through a switch and then connected to the common port to form the coil loop consisting of the electrode and the other at least one electrode.

7. The touch detection device according to any one of claims 1 to 3, characterized in that: The detection module includes a single-ended amplifier and a detection resistor, wherein the detection resistor is located between a first input terminal and an output terminal of the single-ended amplifier or between a first input terminal and a second input terminal of the single-ended amplifier, wherein the first input terminal is used to connect to a first end of the electrode, and the second input terminal is used to connect to a common port.

8. The touch detection device according to any one of claims 1 to 3, characterized in that: The detection module includes a differential amplifier, and detection resistors are arranged between the first input terminal and the first output terminal of the differential amplifier, and between the second input terminal and the second output terminal, or a detection resistor is arranged between the first input terminal and the second input terminal of the differential amplifier, the first input terminal is used to connect the first end of the electrode, and the second input terminal is used to connect the common port.

9. The touch detection device according to any one of claims 1 to 3, characterized in that: The touch detection device further includes a filtering module, which is used to perform low-pass filtering on the signal output by the detection module in the first period, and to perform band-pass filtering on the signal output by the detection module in the second period.

10. A touch screen, characterized in that: include: The touch detection device according to any one of claims 1 to 9; as well as, A plurality of electrodes are connected to the touch detection device.

11. An electronic device, characterized in that: Comprising the touch screen as claimed in claim 10.

12. A touch control system, characterized in that: include: The touch screen as claimed in claim 10; as well as, Electromagnetic pen.

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