CN117762274A - Proximity detection device, touch display screen and electronic equipment - Google Patents
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Abstract
The embodiment of the application provides a proximity detection device, a touch display screen and electronic equipment. The sensor comprises a sensing unit, wherein the sensing unit comprises a sensing electrode and an isolating electrode, and the sensing electrode and the isolating electrode are arranged in an insulating way; the detection circuit is used for converting the sensing capacitance between the sensing electrode and the detection target into a voltage signal; the detection circuit comprises a first operational amplifier and a second operational amplifier; the first input end of the first operational amplifier is connected with the sensing electrode, the second input end of the first operational amplifier is connected with the second input end of the second operational amplifier, the first input end and the output end of the second operational amplifier are connected with the isolating electrode, the second input end of the first operational amplifier and the second input end of the second operational amplifier are input with excitation signals, and the excitation signals are loaded on the sensing electrode and the isolating electrode, so that the sensing electrode and the isolating electrode are equipotential.
Description
Technical Field
The present application relates to the field of capacitive detection, and more particularly, to a proximity detection apparatus, a touch display screen, and an electronic device.
Background
The capacitive sensor is widely applied to the field of man-machine interaction of electronic products, specifically, a capacitance (or called a basic capacitance or an initial capacitance) is formed between a detection electrode and the ground, when a conductor (such as a finger) approaches or touches the detection electrode, the capacitance between the detection electrode and the ground changes, and information of the conductor approaching or touching the detection electrode can be obtained through detecting the change of the capacitance, so that the operation of a user is judged. However, since the base capacitance tends to be relatively large, the amount of capacitance change caused when the conductor approaches or touches the detection electrode is small. In addition, the capacitive sensor is also subject to other spatial coupling interference including power supply noise, common mode interference, digital signal interference and the like, and the signal to noise ratio of capacitive detection is reduced, so that the sensitivity of the existing capacitive detection mode is low, and the capacitive detection cannot be accurately performed.
Disclosure of Invention
In view of the above problems, embodiments of the present application provide a proximity detection apparatus, a touch display screen, and an electronic device, which can reduce a signal-to-noise ratio of capacitive detection and improve detection sensitivity.
In a first aspect, a proximity detection apparatus is provided, the proximity detection apparatus comprising a sensing unit comprising a sensing electrode and an isolation electrode, the sensing electrode and the isolation electrode being arranged in an insulating manner; the detection circuit is used for converting the sensing capacitance between the sensing electrode and the detection target into a voltage signal; the detection circuit comprises a first operational amplifier and a second operational amplifier; the first input end of the first operational amplifier is connected with the sensing electrode, the second input end of the first operational amplifier is connected with the second input end of the second operational amplifier, the first input end and the output end of the second operational amplifier are connected with the isolating electrode, the second input end of the first operational amplifier and the second input end of the second operational amplifier are input with excitation signals, and the excitation signals are loaded on the sensing electrode and the isolating electrode, so that the sensing electrode and the isolating electrode are equipotential.
In the embodiment of the application, the sensing unit comprises a sensing electrode and an isolating electrode, and the sensing electrode is isolated from other interference signals by the isolating electrode; the detection circuit is provided with a first operational amplifier and a second operational amplifier which are respectively connected with the sensing electrode and the isolation electrode, and the same excitation signal is input into the second input end of the first operational amplifier and the second input end of the second operational amplifier, so that the excitation signal is loaded on the sensing electrode and the isolation electrode through the first operational amplifier and the second operational amplifier respectively, so that the potentials of the sensing electrode and the isolation electrode are the same, and the parasitic capacitance between the sensing electrode and the isolation electrode is close to zero. That is, in the technical scheme of the application, the sensing electrode is firstly separated from other interference signals by the isolating electrode, and then the sensing electrode and the isolating electrode are in the same potential by the operational amplifier, so that parasitic capacitance between the sensing electrode and the isolating electrode is eliminated, and when a detection target approaches the sensing electrode, the sensing capacitance between the sensing electrode and the isolating electrode has obvious change compared with the basic capacitance, thereby being beneficial to improving the signal-to-noise ratio of capacitance detection and further improving the detection sensitivity.
In one possible implementation, the voltage signal is used to determine whether there is a detection target.
In one possible implementation, the sampling resistor of the first operational amplifier is connected between the first input of the first operational amplifier and the output of the first operational amplifier.
In one possible implementation, the detection circuit further includes a low pass filter including a resistor and a capacitor; one end of the resistor is connected with the input end of the first operational amplifier, the other end of the resistor is connected with the signal output end and one end of the capacitor, and the other end of the capacitor is grounded.
The low-pass filter can filter out high-frequency signals in the electric signals, allows the low-frequency signals to pass through, and the signals output by the low-pass filter are clearer and easier to analyze and process. The embodiment of the application utilizes the low-pass filter to further filter high-frequency noise and improves the detection sensitivity.
In one possible implementation, the excitation signal is a periodic sine wave signal, or a triangular wave signal, or a square wave signal, or a pulsed signal.
In one possible implementation, the excitation signal is a periodic sine wave signal, and the frequency of the sine wave signal ranges from 10KHz to 1MHz.
In one possible implementation, an insulating layer is provided between the sense electrode and the isolation electrode, which has been electrically insulated.
In one possible implementation, the material of the insulating layer includes at least one of silicon dioxide, silicon nitride.
Silicon dioxide has higher dielectric property and still keeps good insulating property under high temperature condition; silicon nitride is a structural ceramic material with high dielectric properties and high temperature resistance. The insulating layer of the embodiment of the application adopts the materials, so that the sensing electrode and the isolation electrode can be effectively insulated.
In one possible implementation, the isolation electrode is provided with a recess, and the sensing electrode is provided in the recess.
Therefore, the bottom and the periphery of the sensing electrode are surrounded by the isolation electrode, so that other interference signals are isolated more effectively, and the detection sensitivity is further improved.
In one possible implementation, the proximity detection device is disposed on one side of a display module of the electronic device, and the isolation electrode is disposed between the sensing electrode and the display module, where the isolation electrode is used to isolate an electrical signal of the display module.
In this embodiment of the application, the isolation electrode sets up between the display module assembly of sensing electrode and electronic equipment to reduce the signal of telecommunication of display module assembly and to the influence of sensing electrode capacitance variation, reduce noise, improve detection signal to noise ratio and sensitivity.
In a second aspect, a touch display screen is provided, including a proximity detection device in any possible implementation manner of the first aspect.
In one possible implementation, the touch display screen includes a display area and a non-display area, the sensing unit is disposed in the display area, and the detection circuit is disposed in the non-display area.
In a third aspect, an electronic device is provided, including a touch display screen in any possible implementation manner of the second aspect.
In a fourth aspect, there is provided a proximity detection method, comprising: inputting the same excitation signal to the second input terminal of the first operational amplifier and the second input terminal of the second operational amplifier; detecting a voltage of a sense capacitance between the sensing electrode and the detection target; and determining whether a detection target exists according to the voltage.
In one possible implementation, before inputting the same excitation signal to the second input of the first operational amplifier and the second input of the second operational amplifier, the method further comprises: and receiving first indication information sent by the main controller, wherein the first indication information is used for indicating the starting of proximity sensing.
In a fifth aspect, there is provided another proximity detection apparatus comprising: a memory for storing instructions and a processor for executing the memory-stored instructions, and when executed by the processor, causes the processor to perform the method of the fourth aspect or any possible implementation of the fourth aspect.
In a sixth aspect, a computer readable storage medium is provided for storing a computer program comprising instructions for performing the method of the fourth aspect or any possible implementation of the fourth aspect.
In a seventh aspect, a computer product is provided for performing the method of the fourth aspect or any possible implementation of the fourth aspect.
Drawings
FIG. 1 is a schematic block diagram of an electronic device provided in an embodiment of the present application;
FIG. 2 is a schematic block diagram of a proximity detection device provided in an embodiment of the present application;
FIG. 3 is a schematic block diagram of a sensing unit provided in an embodiment of the present application;
FIG. 4 is a schematic block diagram of a sensing unit provided in an embodiment of the present application;
FIG. 5 is a schematic block diagram of a touch display screen provided in an embodiment of the present application;
FIG. 6 is a schematic block diagram of a sensor array unit provided in an embodiment of the present application;
FIG. 7 is a schematic block diagram of a sensor array unit provided in an embodiment of the present application;
fig. 8 is a schematic flow chart of a proximity detection method provided in an embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application.
The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Wherein, in the description of the embodiments of the present application, "/" means or is meant unless otherwise indicated, for example, a/B may represent a or B; "and/or" herein is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone.
The terms "first" and "second" are used below for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In addition, in the description of the present embodiment, unless otherwise specified, the meaning of "a plurality" is two or more.
Reference in the specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," and the like in the specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments" unless expressly specified otherwise. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.
The capacitive sensor is widely applied to the field of man-machine interaction of electronic products, specifically, a capacitance (or called a basic capacitance or an initial capacitance) is formed between a detection electrode and the ground, when a conductor (such as a finger) approaches or touches the detection electrode, the capacitance between the detection electrode and the ground changes, and information of the conductor approaching or touching the detection electrode can be obtained through detecting the change of the capacitance, so that the operation of a user is judged. However, the base capacitance is often larger, the capacitance change amount caused when the conductor approaches or touches the detection electrode is smaller, and the capacitive sensor is also subjected to other spatial coupling interference including power supply noise, common mode interference, digital signal interference and the like, so that the signal to noise ratio of capacitance detection is reduced, and the sensitivity of the existing capacitance detection mode is lower, and the capacitance detection cannot be accurately performed.
In view of this, the embodiment of the application provides a proximity detection device, a touch display screen and an electronic device. Specifically, the proximity detection device separates the sensing electrode from other interference signals by arranging an isolating electrode; and the operational amplifier is used for enabling the sensing electrode and the isolation electrode to be in the same potential, so that parasitic capacitance between the sensing electrode and the isolation electrode is eliminated, and when a detection target approaches the sensing electrode, the sensing capacitance between the sensing electrode and the isolation electrode has obvious change compared with the basic capacitance, thereby being beneficial to improving the signal-to-noise ratio of capacitance detection and further improving the detection sensitivity.
In this embodiment of the present application, the electronic device may be a mobile phone, a tablet computer, a portable computer, a personal digital assistant (Personal Digital Assistant, PDA), a Point of sales (POS), a vehicle-mounted computer, or the like, which is not limited in this embodiment of the present application.
Fig. 1 shows an electronic device 100 provided in an embodiment of the present application, where the electronic device 100 includes: the main controller 110 and the detection device 120 having a capacitive proximity sensing function, wherein the detection device 120 may sense the proximity of a detection target, for example, the proximity of a human hand, using a sensing electrode. The main controller 110 may be responsible for management and control of various components within the electronic device, for example, the main controller 110 may control the detection device 120 to perform proximity sensing, but embodiments of the present application are not limited thereto.
The main controller 110 may be electrically connected to the sensing device 120, alternatively, the main controller 110 may provide a power supply voltage signal to the sensing device 120, but the embodiment is not limited thereto.
Optionally, the detection device 120 and the master controller 110 may also be connected by a communication bus, which may be used to transfer signaling and/or data between the detection device 120 and the master controller 110. At this time, the detection device 120 and the main controller 110 may alternatively have communication interfaces to communicate with each other, respectively, but the embodiment of the present application is not limited thereto.
In the present embodiment, the detection device 120 and the main controller 110 may optionally be further connected by a communication bus, which may be used to transmit signaling and/or data between the detection device 120 and the main controller 110. At this time, the detection device 120 and the main controller 110 may alternatively have communication interfaces to communicate with each other, respectively, but the embodiment of the present application is not limited thereto.
In embodiments of the present application, the detection device 120 may periodically or event-triggered proximity sensing/detection. Alternatively, the detection device 120 may perform proximity sensing under the condition that the electronic device is in an on state or the electronic device is in a bright screen state; alternatively, the detection device 120 may sense proximity under the instruction of the main controller 110. As an alternative example, the main controller 110 may send first indication information to the detecting device 120, where the first indication information may be used to trigger the detecting device 120 to initiate proximity sensing, for example, the first indication information may be used to instruct the electronic device to receive an incoming call or make a phone call, or instruct the user to accept an incoming call or accept an opposite phone call, or the first indication information may be specifically a user instruction for instructing to connect an incoming call, or the embodiment of the present application is not limited to specific implementation of the first indication information. At this time, the detection device 120 may start sensing/detecting proximity according to the first indication information when receiving the first indication information transmitted from the main controller 110, but the embodiment of the present application is not limited thereto.
Alternatively, if the detection means 120 detects the proximity of the detection target, the display screen of the electronic device may be turned off. For example, when the detection device 120 senses the approach of the detection target, it sends second indication information to the main controller 110, where the second indication information may be used to indicate to turn off the display screen of the terminal device, or may further include information related to the detection target, such as a coupling capacitance parameter corresponding to the detection target, and so on. Alternatively, if the detection device 120 does not detect the proximity of the detection target, the display screen of the electronic apparatus may operate normally, i.e., continue to be in a bright screen state. For example, if the detection device 120 does not sense the proximity of the detection target, the detection device 120 may scan the coordinates of the display screen and transmit the scanned coordinate information to the main controller 110. At this time, optionally, the detection device 120 may not send indication information for indicating that the proximity of the conductive object is not sensed to the main controller 110, or the detection device 120 may report the proximity sensing result to the main controller 110 after obtaining the proximity sensing result each time, which is not limited in the embodiment of the present application.
Fig. 2 illustrates a proximity detection apparatus 200 provided in an embodiment of the present application, where the proximity detection apparatus 200 may have a capacitive proximity sensing function. The proximity detection device 200 may be one implementation of the detection device 120 described above.
As shown in fig. 2, the proximity detection apparatus 200 includes a sensing unit 201 and a detection circuit 202.
Specifically, as shown in fig. 2, the sensing unit 201 includes a sensing electrode 2011 and an isolating electrode 2012, and the sensing electrode 2011 and the isolating electrode 2012 are disposed in an insulating manner.
The detection circuit 202 is configured to convert the sensing capacitance between the sensing electrode 2011 and the detection target into a voltage signal, and the voltage signal is used to determine whether the detection target is present.
It should be noted that, the use of the voltage signal described herein to determine whether there is a detection target refers to whether the proximity detection device 200 detects the detection target. For example, when a sensing capacitor is generated between the detection target and the sensing electrode 2011, the sensing capacitor is converted into a voltage signal by the detection circuit 202, so that the detection target can be determined. When no sensing capacitance is generated between the sensing electrode 2011 and the detection target, the detection circuit 202 will not output a corresponding voltage signal, and it can be determined that no detection target is present.
The detection circuit 202 includes a first operational amplifier OP 1 And a second operational amplifier OP 2 The method comprises the steps of carrying out a first treatment on the surface of the Wherein, the first operational amplifier OP 1 A first input terminal connected to the sensing electrode, a first operational amplifier OP 1 Is connected to the second operational amplifier OP 2 A second operational amplifier OP 2 Is connected to the isolation electrode 2012, the first operational amplifier OP 1 And a second operational amplifier OP 2 Is input with a drive signal V driver Excitation signal V driver Is applied to the sensing electrode 2011 and the isolating electrode 2012 such that the sensing electrode 2011 and the isolating electrode 2012 are equipotential.
Exemplary, as shown in FIG. 2, a first operational amplifier OP 1 A first input terminal of (a) and a second operational amplifier OP 2 A first input terminal of (a) can be a negative terminal, a first operational amplifier OP 1 And a second operational amplifier OP 2 The second input terminal of (c) may be the positive terminal.
The two inputs of the operational amplifier have a "virtual short" and "virtual off" mechanism. Specifically, "virtual short" refers to a characteristic that when the operational amplifier is in a linear state, both input ends (first input end and second input end) can be regarded as equipotential, which is called as a false short circuit, and is abbreviated as virtual short. It is obviously impossible to truly short-circuit both inputs. The "virtual break" refers to that when the operational amplifier is in a linear state, the two input ends can be regarded as equivalent open circuits, and the characteristic is called as false open circuits, and is abbreviated as virtual break. It is obviously impossible to truly disconnect both inputs. Therefore, in the embodiment of the application, the equipotential of the sensing electrode and the isolation electrode can be approximately the same potential within the allowable error range under the condition that the operational amplifier works normally.
In the embodiment of the present application, the sensing unit 201 includes a sensing electrode 2011 and an isolation electrode 2012, and the sensing electrode 2011 is isolated from other interference signals by the isolation electrode 2012; the detection circuit is provided with a first operational amplifier OP 1 And a second operational amplifier OP 2 Is connected with the sensing electrode 2011 and the isolating electrode 2012 respectively and is provided with a first operational amplifier OP 1 And a second operational amplifier OP 2 The same excitation signal is input to the second input terminal of the first operational amplifier OP 1 And a second operational amplifier OP 2 The parasitic capacitance between the sense electrode 2011 and the isolation electrode 2012 is close to zero because the potentials of the sense electrode 2011 and the isolation electrode 2012 are the same as each other by loading the sense electrode 2011 and the isolation electrode 2012. That is, in the technical solution of the present application, the sensing electrode 2011 is separated from other interference signals by the isolating electrode 2012, and then the sensing electrode 2011 and the isolating electrode 2012 are at the same potential by the operational amplifier, so that parasitic capacitance between the sensing electrode 2011 and the isolating electrode 2012 is eliminated, and when the detection target approaches the sensing electrode 2011, the sensing capacitance between the sensing electrode 2011 and the isolating electrode is obviously changed compared with the base capacitance, that is, the signal-to-noise ratio of capacitance detection is improved, thereby improving the detection sensitivity.
Exemplary, the isolated electrode 2012 couples the sense electrode 2011 to other interfering signals (e.g., the capacitance C between the isolated electrode 2012 and ground PI ) The isolated, interfering signal may include power supply noise, common mode interference, digital signal interference, and other spatially coupled interference. For example, for a screen of an electronic device, a display layer of the screen may generate larger noise interference when scanning, and a data line between a main control unit and a control unit, a data line connected between the display control unit and the display screen, for example, an interference signal generated by a Low voltage differential signaling (Low-Voltage Differential Signaling, LVDS) data line to touch, and an interference caused by a data structure flip to a touch key signal.
In some embodiments, the proximity detection apparatus 200 is disposed on one side of a display module of the electronic device, the isolation electrode 2012 is disposed between the sensing electrode 2011 and the display module, and the isolation electrode 2012 is used for isolating an electrical signal of the display module.
In the embodiment of the application, the isolating electrode 2012 is disposed between the sensing electrode 2011 and the display module, a large amount of signal noise in the display module is first coupled to the isolating electrode 2012, and a part of the noise is transmitted to the excitation signal V through the isolating electrode 2012 driver With only a small part of the noise passing through C PS And the display module is coupled to the sensing electrode 2011, so that noise from the display module to the sensing electrode 2011 is reduced, and the signal-to-noise ratio of capacitance detection is improved.
In some embodiments, an insulating layer may be disposed between the isolation electrode 2012 and the sense electrode 2011.
Illustratively, as shown in fig. 3, an insulating layer is disposed only between the top end of the isolation electrode 2012 and the bottom end of the sensing electrode 2011, at this time, the isolation electrode 2012, the insulating layer, and the sensing electrode 2011 are disposed in order along the x-direction, and both ends of the isolation electrode 2012 and the sensing electrode 2011 are aligned in the y-direction.
Illustratively, the isolated electrode 2012 is provided with a recess as shown in fig. 4, and the sense electrode 2011 is disposed within the recess. At this time, the bottom and the periphery of the sensing electrode 2011 are surrounded by the isolating electrode 2012, so that other interference signals are isolated more effectively, and the detection sensitivity is further improved. At this time, an insulating layer is disposed between the bottom end of the sensing electrode 2011 and the bottom wall of the groove, and an insulating layer is also disposed between the periphery of the sensing electrode 2011 and the inner sidewall of the groove.
Alternatively, the end of the groove in one direction may be flush with the end of the insulated electrode 2012 in the one direction, at which time the bottom end of the sensing electrode 2011 and both sides are insulated from the outside by the insulated electrode 2012.
Optionally, the material of the insulating layer includes at least one of silicon dioxide and silicon nitride.
In some embodiments, as shown in FIG. 1, a first operational amplifier OP 1 Is connected to the first operational amplifier OP 1 A first input terminal of (a) and a first operational amplifier OP 1 Is provided between the outputs of (c).
In some embodiments, as shown in FIG. 1, detectionThe circuit 202 further includes a low pass filter RC including a resistor R LPF And capacitor C LPF The method comprises the steps of carrying out a first treatment on the surface of the Wherein the resistance R LPF One end of (a) is connected to the first operational amplifier OP 1 Input terminal of (a), resistance R LPF The other end of the capacitor is connected with the signal output end and is connected with the capacitor C LPF Capacitance C LPF The other end of which is grounded.
The low-pass filter can filter out high-frequency signals in the electric signals, allows the low-frequency signals to pass through, and the signals output by the low-pass filter are clearer and easier to analyze and process. The embodiment of the application utilizes the low-pass filter to further filter high-frequency noise and improves the detection sensitivity.
In this embodiment of the present application, the sensing electrode 2011 is firstly separated from other interference signals by the isolating electrode 2012, and then parasitic capacitance between the isolating electrode 2012 and the sensing electrode 2011 is reduced by the operational amplifier, so that noise in a voltage signal output by the operational amplifier is reduced, and then high-frequency noise in the voltage signal is filtered by the low-pass filter, so as to improve detection sensitivity. The technical solutions of the present application are exemplarily explained below.
The proximity detection device 200 inputs an excitation signal V driver Then according to the first operational amplifier OP 1 A virtual short and virtual break mechanism applied to the first operational amplifier OP 1 Is a second input terminal of the first voltage source driver Also in the first operational amplifier OP 1 Generates an excitation signal V at the first input terminal of (1) driver Then the first operational amplifier OP 1 The total input capacitance of the first input of (a) is equivalent to the parasitic capacitance C between the sense electrode 2011 and the isolation electrode 2012 PS And a sense capacitor C int In parallel, i.e. C int +C PS . Yielding a total capacitive reactance xc=1/(2pi f (C) int +C PS ) A) excitation signal V driver The generated current I driver ＝V driver /Xc＝2πf(C int +C PS )*V driver Generating a voltage drop V across the sampling resistor Rs 1 ＝I driver *Rs＝2πf(C int +C PS )*V driver *Rs。
When a detection target (e.g., a hand) approaches the sensing electrode 2011, a capacitance C is induced int Changes and the generated induction capacitance is C int +ΔC int At this time, a voltage drop V is generated across the collecting resistor Rs 2 ＝2πf(C int +ΔC int +C PS )*V driver * Rs, the induced signal thus generated is Δv=v 2 -V 1 ＝2πf*ΔC int *V driver *Rs。
The change of the induction signal relative to the original acquisition signal is delta V/V 1 ＝ΔC int /(C int +C PS )。
In the embodiment of the present application, the detection circuit is provided with a first operational amplifier OP 1 And a second operational amplifier OP 2 So that parasitic capacitance C between sense electrode 2011 and isolation electrode 2012 PS Zero elimination, thus DeltaV/V 1 ＝ΔC int /(C int +C PS )＝ΔC int /C int 。
In some embodiments, the excitation signal V driver Is a periodic sine wave signal, or a triangular wave signal, or a square wave signal, or a pulse signal.
Optionally, the excitation signal V driver The frequency of the sine wave signal is in the range of 10 KHz-1 MHz.
Specifically, as excitation signal V driver The frequency of the sine wave signal of (a) can be 10KHz, 15KHz, 20KHz, 25KHz, 50KHz, 100KHz, 1MHz, or the value thereof is within the range obtained by the combination of any two values.
In some embodiments, the sensing electrode 2011 may be a low resistivity metal electrode, such as a metallic copper electrode, or a molybdenum aluminum molybdenum, or a titanium aluminum titanium electrode.
In some embodiments, the isolation electrode 2012 may be a low resistivity metal electrode, such as a metallic copper electrode, or a molybdenum aluminum molybdenum, or titanium aluminum titanium electrode.
It should be understood that the sensing electrode 2011 and the isolating electrode 2012 may be made of the same material, or may be made of different materials, which is not limited in this embodiment of the present application.
In some embodiments, the proximity detection apparatus 200 may further include a processing circuit for performing information processing on the voltage signal output from the detection circuit 202, and outputting a high level or a low level.
The embodiment of the application also provides a touch display screen, which comprises the proximity detection device in any possible implementation embodiment.
In some embodiments, as shown in fig. 5, the touch display screen 300 includes a display area 301 and a non-display area 302, the sensing unit 201 is disposed in the display area 301, and the detection circuit 202 is disposed in the non-display area 302.
In some embodiments, the display area 301 is provided with a plurality of sensor array units.
Optionally, the display area is provided with a display module, and n+m sensing array units are arranged on the display module.
Specifically, n rows and m columns of sensing units are arranged on the display module, and each sensing unit in the n rows of sensing units is crossed with each sensing unit in the m columns of sensing units. One sensing unit in the n rows of sensing units and one sensing unit in the m columns of sensing units are arranged in a crossing mode to form a sensing array unit. The n rows and m columns of sensing units are arranged in a crossing manner to form n+m sensing array units.
For example, as shown in fig. 6, 5+5 sensing array units are disposed on the display module. Each of the sensor array units includes one sensor unit 201 (hereinafter, referred to as "longitudinal sensor unit 201") extending in the z-direction and one sensor unit 201 (hereinafter, referred to as "lateral sensor unit 201") extending in the y-direction, the longitudinal sensor unit 201 and the lateral sensor unit 201 being disposed to intersect. Wherein the x-direction, the y-direction and the z-direction are perpendicular to each other.
In this embodiment, each sensing unit 201 in the sensing array unit is connected to a detection circuit.
In some embodiments, as shown in fig. 7, the sensing unit 201 is in an "i" shaped structure. In this way, the overlapping area at the intersection of the longitudinal sensing unit 201 and the lateral sensing unit 201 is reduced, thereby reducing signal interference therebetween.
Specifically, the width L of both ends of the sensing unit 201 1 A width L greater than its intermediate position 2 。
In some embodiments, the touch display screen may include a touch chip, and the sensing unit 201, the detection circuit, and the processing circuit may be integrated in the touch chip. The touch chip may be a capacitive touch chip.
The embodiment of the application also provides electronic equipment which can comprise the touch display screen.
The proximity detection device, the touch display screen and the electronic device provided in the embodiments of the present application are described in detail above with reference to fig. 1 to 7, and the proximity detection method provided in the embodiments of the present application is described below with reference to fig. 8.
Fig. 8 illustrates a proximity detection method 400 provided by an embodiment of the present invention. The method 400 may be applied to an electronic device, where the electronic device may be specifically an electronic device as described above, but embodiments of the present invention are not limited thereto.
Specifically, the method 400 includes:
s410, the same excitation signal is input to the second input terminal of the first operational amplifier and the second input terminal of the second operational amplifier.
S420, detecting the voltage of the sensing capacitor between the sensing electrode and the detection target.
S430, determining whether a detection target exists according to the voltage.
A sense capacitor is formed between the sense electrode 2011 and a detection target near the sense electrode 2011, and voltage information generated by the sense capacitor formed by coupling the sense electrode 2011 and the detection target can be detected by using an excitation signal whose amplitude changes with time.
Alternatively, the excitation signal may be a periodic sine wave signal, or a triangular wave signal, or a square wave signal, or a pulse signal.
Optionally, before S410, the method 400 further includes:
and receiving first indication information sent by the main controller, wherein the first indication information is used for indicating the starting of proximity sensing.
Accordingly, S410, inputting the excitation signal to the second input terminal of the first operational amplifier and the second input terminal of the second operational amplifier, includes:
based on the first indication information, an excitation signal is input to a second input terminal of the first operational amplifier and a second input terminal of the second operational amplifier.
Optionally, the method 400 may further include: and sending a determination result of whether the detection target exists or not to the main controller.
It should be understood that the sequence numbers of the above processes do not mean the order of execution, and the execution order of the processes should be determined by the functions and internal logic of the processes, and should not be construed as limiting the implementation process of the embodiments of the present invention.
The embodiment of the application also provides another proximity detection device, which comprises: a processor and a memory, wherein the memory is configured to store instructions, and the processor is configured to execute the instructions stored in the memory, wherein execution of the instructions causes the processor to perform the detection method in the above embodiment.
The embodiment of the application also provides a processor for executing the method of the embodiment.
The embodiment of the application also provides a computer product for executing the method of the embodiment.
Embodiments of the present application also provide a computer-readable storage medium storing a computer program comprising a method for performing the steps and/or the flow of the method of the above embodiments.
It is to be understood that in embodiments of the present application, the term "unit" may refer to an application specific integrated circuit (Application Specific Integrated Circuit, ASIC), an electronic circuit, a processor (e.g., a shared, dedicated, or group processor, etc.) and memory that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that support the described functionality.
In an alternative example, it will be understood by those skilled in the art that the apparatus may be specifically configured in the foregoing embodiment, and the apparatus may be configured to perform each corresponding flow and/or step in the foregoing method embodiment, which is not described herein for avoiding repetition.
It should be appreciated that in embodiments of the invention, the processor may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital upstream signal processors, application specific integrated circuits, off-the-shelf programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
The memory may include read only memory and random access memory and provide instructions and data to the processor. A portion of the memory may also include non-volatile random access memory. For example, the memory may also store information of the device type. The processor may be configured to execute the instructions stored in the memory, and when the processor executes the instructions, the processor may perform the steps corresponding to the terminal device in the above method embodiment.
In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or by instructions in the form of software. The steps of a method disclosed in connection with the embodiments of the present invention may be embodied directly in a hardware processor for execution, or in a combination of hardware and software modules in the processor for execution. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in a memory, and the processor executes instructions in the memory to perform the steps of the method described above in conjunction with its hardware. To avoid repetition, a detailed description is not provided herein.
Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.
In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.
The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.
In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.
The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.
The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (13)
1. A proximity detection apparatus, comprising:
the sensing unit comprises a sensing electrode and an isolating electrode, and the sensing electrode and the isolating electrode are arranged in an insulating way;
the detection circuit is used for converting the induction capacitance between the sensing electrode and the detection target into a voltage signal;
the detection circuit comprises a first operational amplifier and a second operational amplifier;
the first input end of the first operational amplifier is connected with the sensing electrode, the second input end of the first operational amplifier is connected with the second input end of the second operational amplifier, the first input end and the output end of the second operational amplifier are connected with the isolating electrode, the second input end of the first operational amplifier and the second input end of the second operational amplifier input excitation signals, and the excitation signals are loaded on the sensing electrode and the isolating electrode, so that the sensing electrode and the isolating electrode are equipotential.
2. The proximity detection apparatus according to claim 1, wherein the voltage signal is used to determine whether the detection target is present.
3. The proximity detection apparatus according to claim 1 or 2, wherein the sampling resistor of the first operational amplifier is connected between the first input terminal of the first operational amplifier and the output terminal of the first operational amplifier.
4. A proximity detection apparatus according to any one of claims 1 to 3, wherein the detection circuit further comprises a low pass filter comprising a resistor and a capacitor;
one end of the resistor is connected to the output end of the first operational amplifier, the other end of the resistor is connected to the signal output end and one end of the capacitor, and the other end of the capacitor is grounded.
5. The proximity detection apparatus according to any one of claims 1 to 4, wherein the excitation signal is a periodic sine wave signal, or a triangular wave signal, or a square wave signal, or a pulse signal.
6. The proximity detection apparatus according to claim 5, wherein the excitation signal is a periodic sine wave signal, and the frequency of the sine wave signal is in a range of 10KHz to 1MHz.
7. The proximity detection apparatus according to any one of claims 1 to 6, wherein an insulating layer is provided between the sensing electrode and the isolation electrode.
8. The proximity detection apparatus according to claim 7, wherein the material of the insulating layer includes at least one of silicon dioxide and silicon nitride.
9. The proximity detection apparatus according to claim 7 or 8, wherein the isolation electrode is provided with a groove, and the sensing electrode is provided in the groove.
10. The proximity detection apparatus according to any one of claims 1 to 9, wherein the proximity detection apparatus is provided on one side of a display module of an electronic device, the isolation electrode is provided between the sensing electrode and the display module, and the isolation electrode is used to isolate an electrical signal of the display module.
11. A touch display screen comprising a proximity detection apparatus as claimed in any one of claims 1 to 10.
12. The touch display screen of claim 11, wherein the touch display screen comprises a display area and a non-display area, the sensing unit is disposed in the display area, and the detection circuit is disposed in the non-display area.
13. An electronic device comprising a touch-sensitive display according to claim 11 or 12.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311861498.6A CN117762274A (en) | 2023-12-29 | 2023-12-29 | Proximity detection device, touch display screen and electronic equipment |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202311861498.6A CN117762274A (en) | 2023-12-29 | 2023-12-29 | Proximity detection device, touch display screen and electronic equipment |
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| CN117762274A true CN117762274A (en) | 2024-03-26 |
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| CN202311861498.6A Pending CN117762274A (en) | 2023-12-29 | 2023-12-29 | Proximity detection device, touch display screen and electronic equipment |
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| CN (1) | CN117762274A (en) |
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