WO2017143823A1

WO2017143823A1 - Method and device for achieving electromagnetic interference resistance of capacitive touchscreen

Info

Publication number: WO2017143823A1
Application number: PCT/CN2016/107737
Authority: WO
Inventors: 王双军
Original assignee: 上海斐讯数据通信技术有限公司
Priority date: 2016-02-25
Filing date: 2016-11-29
Publication date: 2017-08-31
Also published as: CN105786281A

Abstract

A method and device for achieving electromagnetic interference resistance of a capacitive touchscreen, the method comprising: acquiring data of an induction region of a capacitive touchscreen (S1); judging whether a shape of the induction region of the capacitive touchscreen is in compliance with a preset rule (S2); if yes, reporting the data of the induction region of the capacitive touchscreen; and if no, not reporting (S3). By means of the present method, the electromagnetic interference resistance of the capacitive touchscreen may be enhanced, and the impact of electromagnetic interference may be reduced.

Description

Method and device for resisting electromagnetic interference of capacitive screen

Technical field

The invention relates to the field of electrical appliances, and in particular to a method and a device for resisting electromagnetic interference of a capacitive screen.

Background technique

With the advancement and development of technology, today's mobile terminals, such as mobile phones, use capacitive touch screens. Capacitive touch screen technology uses the current sensing of the human body to work.

But for this reason, the current capacitive screen of mobile phones is very susceptible to external electromagnetic interference, causing problems with jumping points. This problem requires the test engineer to do a lot of testing in the research and development stage. Then the R&D engineer finds the corresponding interference source according to the measured problem. After a lot of trial and modification, the test is passed again to ensure the stability of the mobile phone after the mobile phone is shipped. Sex. However, there are still some machines that are shipped, and in some complicated scenarios, touch screen anomalies are still inevitable. There are many problems caused by the jumping point. For example, the mobile phone automatically dials out the phone, the mobile phone touch sensor constantly clicks on a certain area, and the finger touch is not sensitive, which plagues the user.

At present, the most common means of resisting electromagnetic interference is to change the firmware of the capacitive screen to enhance the anti-interference ability matched with different interference sources. For example, the interference of the display screen, the interference of the mobile phone antenna, the high current interference during charging, etc., will affect the capacitive screen to varying degrees. When the R&D engineer encounters the jump point problem, it is necessary to find the interference source and modify it. The firmware of the touch screen enhances the anti-jamming capability of this aspect. However, the enhanced anti-interference ability is not as strong as possible, and the anti-interference ability is enhanced, and the sensitivity of the touch may be lowered. This is also the biggest headache for mobile phone R&D engineers. It must be effective and not easily disturbed.

It should be noted that the above description of the technical background is only for the purpose of facilitating a clear and complete description of the technical solutions of the present application, and is convenient for understanding by those skilled in the art. The above technical solutions are not considered to be well known to those skilled in the art simply because these aspects are set forth in the background section of this application.

Summary of the invention

In view of the above drawbacks of the prior art, the technical problem to be solved by the present invention is to provide a method and apparatus for resisting electromagnetic interference of a capacitive screen capable of reducing electromagnetic interference.

To achieve the above object, the present invention provides a method for resisting electromagnetic interference of a capacitive screen, comprising the steps of:

Obtaining capacitive screen sensing area data;

Determining whether the shape of the capacitive screen sensing area conforms to a preset regular shape;

If it is met, the capacitive touch screen sensing area data is reported; if it is not, the report is not reported.

Further, the step of determining whether the shape of the capacitive screen sensing area conforms to a preset regular shape comprises:

Determining whether the difference between the shape of the capacitive screen sensing area and the preset regular shape meets a preset threshold. If yes, determining that the shape of the capacitive screen sensing area conforms to a preset regular shape. Although the shape of the capacitive screen sensing area that we use to trigger with a mobile phone is mostly regular, it is not an absolutely regular shape. Therefore, in this scheme, the setting is The concept of the difference value may be considered as conforming to the preset rule shape if the difference value does not exceed the preset threshold. If the preset threshold is exceeded, the shape of the capacitive screen sensing area is not in accordance with the preset rule shape. No need to report.

Further, the preset rule shape includes at least a preset elliptical shape and a preset circular shape. At present, in most cases, the touch input is controlled by finger touch, and is generally triggered by the finger finger, which also means that if the capacitive touch area is controlled by a finger, The shape is basically independent of the elliptical and round-like shapes. In addition, it can be considered as non-human control input.

A horizontal axis tangent line and a vertical axis tangent line are respectively performed on the capacitive screen sensing area, and it is determined whether the number of the capacitive channels spanned by the horizontal axis tangent line and the number axis tangent line meets a preset number. If yes, the difference value is determined to be less than or equal to the threshold value. The horizontal axis and the numerical axis generally refer to the lateral position of the capacitive screen sensing area in the lateral direction and the vertical direction, and the horizontal axis tangent line and the vertical axis tangent line are crisscrossed. If the two do not intersect, the tangent line may be regarded as not the horizontal axis tangent line or the vertical axis. Tangent, no further steps are carried out; the size and size of our human fingers, especially the fingertips commonly used for touch input, are limited. Correspondingly, the number of capacitive channels that can be crossed is also limited. It is only one or two capacitor channels wide, then it can be assumed that the capacitive screen sensing area is not considered input, because the human finger cannot be so small; similarly, if the number of capacitive channels spanning is too large, it can be considered that the input is not considered There is no need to report, because even if it is not electromagnetic interference, but the body part of the person is triggered, it can only be partially mishandled by the palm, etc., it can be determined that it is unintentional to touch, and it can be reduced without reporting. Jump or misuse.

After the coordinate point of the capacitive sensing area in the sensing area of the capacitive screen is lower than the preset capacitance value, it is determined whether the shape of the capacitive sensing area conforms to a preset regular shape. Although the capacitive touch screen multi-finger touch will cause the change of the capacitance therein, in fact, in time, the direct contact with the touch, the other body parts close to the capacitive screen may still cause the change of the capacitance therein, thereby affecting the judgment result. However, if the contact capacitance is not directly touched, the value of the induced capacitance should be relatively low. After removing this part of the data, the shape of the sensing area of the capacitive screen can be judged to improve the accuracy. In addition, many weak electromagnetic interferences are caused. Most of the changes in capacitance are intended to be relatively small. Eliminating this part of the data can also reduce the impact of electromagnetic interference.

Further, after the step of determining whether the shape of the capacitive screen sensing area conforms to the preset rule shape, the method further includes the following steps:

Detecting whether the central capacitance sensing amount of the capacitive screen sensing area meets the preset sensing quantity threshold, and if yes, reporting the coordinate point. Although the central capacitance induction caused by the finger touch input is weak, it is much larger than most electromagnetic interference, and the data far lower than the normal center capacitance induction can be eliminated, which can reduce the influence of electromagnetic interference. Similarly, It is also possible to reject data that is much higher than the normal center capacitance.

Further, the step of detecting whether the central capacitance sensing amount of the capacitive screen sensing area meets a preset sensing amount threshold comprises:

Extracting a coordinate point having the largest value of the induced capacitance in the sensing area of the capacitive screen, and determining Whether the value of the sensing capacitance of the coordinate point is greater than a preset sensing amount threshold, and if it is greater than, determining that the central capacitance sensing amount meets the preset sensing amount threshold. Explain the specific situation of the central capacitance sensing. The central capacitive sensing quantity generally refers to the coordinate point where the value of the sensing capacitance in the sensing area of the capacitive screen is the largest, or the value of the sensing capacitance of the center point of the area of the sensing area of the entire capacitive screen.

Extracting a preset number of coordinate points having the largest value of the sensing capacitance in the sensing area of the capacitive screen, and determining whether the position of the coordinate point meets a preset spacing, if the distance between the coordinate points is within a preset spacing, Then, it is determined that the central capacitance sensing amount meets the preset sensing amount threshold. If the capacitive touch sensing area is input by a finger touch, it can be considered that there should be a certain number of coordinate points, for example, three or five coordinate points having relatively large sensing capacitance values, which is the center position of the finger touch. And the plurality of coordinate points should be adjacent to each other, which is in line with reality, if the coordinate points of the plurality of large sensing capacitance values existing in the sensing area of the capacitive screen are in the north and the sensing capacitance values of the coordinate points existing between each other Far below them, it can be basically determined that the capacitive sensing area is not a human touch input; using this scheme can improve the anti-electromagnetic interference capability.

Further, determining whether the sensing capacitance values of all the coordinate points of the preset number are greater than a preset sensing amount threshold, and if both are greater than, determining that the central capacitance sensing amount meets the preset sensing amount threshold. According to the normal situation, the touch input, due to the touch area of the finger, will cause a considerable number of sensing capacitance values to exceed the preset sensing threshold. If there is no threshold value in the capacitive screen. The coordinate point exists, or the number is too small, then it can be basically determined that the capacitive screen sensing area is not artificial input, and should not It should be reported.

Further, the capacitive screen sensing area is a continuous area on the capacitive screen that detects a change in capacitance. If two or more capacitive screen sensing areas are detected at the same time, the sensing areas of the respective capacitive screens are respectively determined. Whether the shape conforms to the preset rule shape. Obtaining, judging and analyzing the upload separately can avoid the occurrence of errors to a certain extent and help to reduce electromagnetic interference.

An apparatus for resisting electromagnetic interference using any of the methods of the present invention, comprising:

a mobile terminal processor for managing and controlling processing and interaction of data of the mobile terminal;

a capacitive screen chip for acquiring capacitive screen sensing area data;

a judging module, configured to determine whether a shape of the capacitive screen sensing area conforms to a preset regular shape;

If yes, the determining module controls the capacitive screen chip to report the capacitive screen sensing area data to the mobile terminal processor; if not, the reporting is not performed.

The method of the present invention adds a mechanism for judging whether the shape of the capacitive screen sensing area conforms to a preset regular shape, which enables the mobile terminal to filter the capacitive screen sensing area data before uploading the capacitive screen sensing area data. The sensing area of the screen is triggered by the finger, and the shape of the obtained capacitive screen sensing area can be expected to be a predetermined regular shape like an ellipse or a circle, and this part is reported by the capacitive screen IC. Reported to the mobile phone processor for processing; and for other situations, for example, if the capacitive screen receives electromagnetic interference, the shape of the capacitive screen sensing area formed by the electromagnetic interference is likely not to be a preset rule shape. If you do not report, you can reduce the occurrence of hopping on the capacitive screen due to electromagnetic interference. Moreover, due to this mechanism, When the capacitive screen is designed for anti-interference, it can reduce the appearance of changing the firmware of the capacitive screen, thereby ensuring the sensitivity of the capacitive screen, improving the anti-interference ability of the capacitive screen and improving the touch sensitivity of the capacitive screen.

Specific embodiments of the present application are disclosed in detail with reference to the following description and accompanying drawings, in which <RTIgt; It should be understood that the embodiments of the present application are not limited in scope. The embodiments of the present application include many variations, modifications, and equivalents within the scope of the appended claims.

Features described and/or illustrated with respect to one embodiment may be used in one or more other embodiments in the same or similar manner, in combination with, or in place of, features in other embodiments. .

It should be emphasized that the term "comprising" or "comprises" or "comprising" or "comprising" or "comprising" or "comprising" or "comprises"

DRAWINGS

The drawings are included to provide a further understanding of the embodiments of the present application, and are intended to illustrate the embodiments of the present application Obviously, the drawings in the following description are only some of the embodiments of the present application, and those skilled in the art can obtain other drawings according to the drawings without any inventive labor. In the drawing:

1 is a flow chart of a method for resisting electromagnetic interference of a capacitive screen according to an embodiment of the invention.

2 is a schematic diagram of capacitance values of a capacitive screen without touch input according to an embodiment of the present invention;

3 is a schematic diagram showing capacitance values of a finger touch input of a capacitive screen according to an embodiment of the present invention;

4 is a schematic diagram showing capacitance values of a capacitive screen according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a device for resisting electromagnetic interference of a capacitive screen according to Embodiment 2 of the present invention.

detailed description

The technical solutions in the embodiments of the present application are clearly and completely described in the following, in which the technical solutions in the embodiments of the present application are clearly and completely described. The embodiments are only a part of the embodiments of the present application, and not all of them. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application without departing from the inventive scope should fall within the scope of the present application.

Embodiment 1:

1 is a flow chart of a method for resisting electromagnetic interference of a capacitive screen according to an embodiment of the invention, the method comprising the steps of:

S1: acquiring capacitive screen sensing area data;

S2: determining whether the shape of the capacitive screen sensing area conforms to a preset rule shape;

S3: If it is met, the capacitive screen sensing area data is reported; if it is not, the report is not performed.

The method of the present invention adds a mechanism for judging whether the shape of the capacitive screen sensing area conforms to a preset regular shape, which enables the mobile terminal to filter the capacitive screen sensing area data before uploading the capacitive screen sensing area data. The sensing area of the screen is triggered by the finger, so the shape of the obtained capacitive screen sensing area can be expected to be a class A predetermined regular shape, such as an ellipse or a circle-like shape, is reported to the mobile phone processor for processing by the capacitive screen IC; and for other cases, for example, if the capacitive screen receives electromagnetic interference, Then, the shape of the capacitive screen sensing area formed by the electromagnetic interference may not be the preset regular shape. If the reporting is not made in this part of the situation, the capacitive screen may be reduced due to electromagnetic interference, and Due to this mechanism, when the capacitive screen is designed for anti-interference, the situation of changing the firmware of the capacitive screen can be reduced, thereby ensuring the sensitivity of the capacitive screen, thereby improving the anti-interference ability of the capacitive screen and improving the touch sensitivity of the capacitive screen. .

Specifically, the types of electromagnetic interference include LCD interference, mobile phone antenna interference, large current interference during charging, or external electromagnetic interference. If you change the firmware to enhance the anti-interference ability for each different interference source, you can not only take into account And it will seriously affect the touch sensitivity, and without using the method of the present invention, such a problem does not occur.

Preferably, in the embodiment, the step of determining whether the shape of the capacitive screen sensing area conforms to the preset regular shape comprises:

It is determined whether the difference between the shape of the capacitive screen sensing area and the preset regular shape meets a preset threshold. If yes, it is determined that the shape of the capacitive screen sensing area conforms to a preset regular shape. Although the shape of the capacitive screen sensing area triggered by the user's mobile phone is mostly regular, it is not an absolutely regular shape. Therefore, in this solution, the concept of the difference value is set, as long as the difference value does not exceed the preset threshold. It can be considered as conforming to the shape of the preset rule. If the preset threshold is exceeded, it indicates that the shape of the capacitive screen sensing area does not conform to the preset rule shape and need not be reported.

Preferably, the preset rule shape includes at least a preset elliptical shape and a preset. Round shape. At present, in most cases, the touch input is controlled by finger touch, and is generally triggered by the finger finger, which also means that if the capacitive touch area is controlled by a finger, The shape is basically independent of the elliptical and round-like shapes. In addition, it can be considered as non-human control input.

The transverse axis tangent and the vertical axis tangent are respectively performed on the capacitive screen sensing area, and it is determined whether the number of capacitive channels spanned by the horizontal axis tangent line and the number axis tangent line meets a preset number. If yes, the difference value is determined to be less than or equal to the threshold value. The horizontal axis and the numerical axis generally refer to the lateral position of the capacitive screen sensing area in the lateral direction and the vertical direction, and the horizontal axis tangent line and the vertical axis tangent line are crisscrossed. If the two do not intersect, the tangent line may be regarded as not the horizontal axis tangent line or the vertical axis. Tangent, no further steps are carried out; the size and size of our human fingers, especially the fingertips commonly used for touch input, are limited. Correspondingly, the number of capacitive channels that can be crossed is also limited. It is only one or two capacitor channels wide, then it can be assumed that the capacitive screen sensing area is not considered input, because the human finger cannot be so small; similarly, if the number of capacitive channels spanning is too large, it can be considered that the input is not considered There is no need to report, because even if it is not electromagnetic interference, but the body part of the person is triggered, it can only be partially operated by the palm of the hand. It can be judged to be unintentional. If you do not report it, you can reduce the jump point or Misoperation.

After the coordinate point in the sensing area of the capacitive screen is lower than the preset capacitance value, Then determine whether the shape of the capacitive sensing area conforms to the preset regular shape. Although the capacitive touch screen multi-finger touch will cause the change of the capacitance therein, in fact, in time, the direct contact with the touch, the other body parts close to the capacitive screen may still cause the change of the capacitance therein, thereby affecting the judgment result. However, if the contact capacitance is not directly touched, the value of the induced capacitance should be relatively low. After removing this part of the data, the shape of the sensing area of the capacitive screen can be judged to improve the accuracy. In addition, many weak electromagnetic interferences are caused. Most of the changes in capacitance are intended to be relatively small. Eliminating this part of the data can also reduce the impact of electromagnetic interference.

Preferably, in the embodiment, the step of determining whether the shape of the capacitive screen sensing area conforms to the preset regular shape further comprises the following steps:

Detect whether the center capacitance of the capacitive sensing area meets the preset sensing threshold. If it matches, report the coordinate point. Although the central capacitance induction caused by the finger touch input is weak, it is much larger than most electromagnetic interference, and the data far lower than the normal center capacitance induction can be eliminated, which can reduce the influence of electromagnetic interference. Similarly, It is also possible to reject data that is much higher than the normal center capacitance.

Preferably, in the embodiment, the step of detecting whether the central capacitance sensing amount of the capacitive screen sensing area meets the preset sensing quantity threshold comprises:

Extracting a coordinate point having the largest value of the sensing capacitance in the sensing area of the capacitive screen, and determining whether the value of the sensing capacitance of the coordinate point is greater than a preset sensing amount threshold. If it is greater than, determining that the central capacitance sensing quantity meets the preset sensing quantity threshold. Explain the specific situation of the central capacitance sensing. The central capacitive sensing quantity generally refers to the coordinate point where the value of the sensing capacitance in the sensing area of the capacitive screen is the largest, or the value of the sensing capacitance of the center point of the area of the sensing area of the entire capacitive screen.

Specifically, the preset sensing amount threshold may be set to 50 PF, if the capacitive screen sensing area If the maximum value of the sensed capacitance is less than this value, it can be assumed that the input is a non-human input (refer to Figure 3).

Extract a coordinate point with the largest value of the sensing capacitance in the preset number of capacitive screen sensing areas, and determine whether the position of the coordinate point conforms to the preset spacing. If the distance between the coordinate points is within the preset spacing, determine the central capacitance sensing amount. Meets the preset sensing threshold. If the capacitive touch sensing area is input by a finger touch, it can be considered that there should be a certain number of coordinate points, for example, three or five coordinate points having relatively large sensing capacitance values, which is the center position of the finger touch. And the plurality of coordinate points should be adjacent to each other, which is in line with reality, if the coordinate points of the plurality of large sensing capacitance values existing in the sensing area of the capacitive screen are in the north and the sensing capacitance values of the coordinate points existing between each other Far below them, it can be basically determined that the capacitive sensing area is not a human touch input; using this scheme can improve the anti-electromagnetic interference capability.

Preferably, in this embodiment, it is determined whether the sensing capacitance values of all the coordinate points of the preset number are greater than a preset sensing amount threshold. If both are greater than, the central capacitance sensing amount is determined to be consistent with the preset sensing amount threshold. According to the normal situation, the touch input, due to the touch area of the finger, will cause a considerable number of sensing capacitance values to exceed the preset sensing threshold. If there is no threshold value in the capacitive screen. The coordinate point exists, or the number is too small, then it can be basically determined that the capacitive screen sensing area is not artificially input and should not be reported.

In this embodiment, the capacitive screen sensing area is a coherent detection on the capacitive screen. In the area where the capacitance changes, if two or more capacitive screen sensing areas are detected at the same time, it is determined whether the shape of each capacitive screen sensing area conforms to a preset regular shape. Obtaining, judging and analyzing the upload separately can avoid the occurrence of errors to a certain extent and help to reduce electromagnetic interference.

FIG. 2 is a schematic diagram showing the capacitance value of the capacitive screen without touch input according to the embodiment of the present invention; FIG. 3 is a capacitive touch screen finger touch according to an embodiment of the present invention; Schematic diagram of the capacitance value of the control input; FIG. 4 is a schematic diagram of the capacitance value of the capacitive screen of the embodiment of the present invention subjected to electromagnetic interference.

Referring to FIG. 2, FIG. 3 and FIG. 4, the shape of the capacitive screen sensing area input by the finger touch is approximately elliptical, which can approximate the long axis and the end state of the ellipse by the center point around the sensing area of the capacitive screen. Judging to determine, the shape of the capacitive screen sensing area caused by electromagnetic interference may appear as a general strip shape, and the short axis direction, the number of capacitive channels spanning only two, according to analysis and judgment, It is obvious that the situation shown in FIG. 3 is an artificial normal input, which can be reported, and in the case of FIG. 4, the electromagnetic interference is input, and the rejection is required without reporting, and the present invention achieves the improvement of the capacitive screen anti-interference by such a method. The purpose of the capability, and because of the need to modify the firmware to cope with possible interferences from various manufacturers, because the good touch sensitivity is ensured, the capacitive screen of the present invention can adapt to a wider variety of working environments.

Furthermore, from the figure, it can be found that the value of the sensing capacitance caused by the finger touch input has a range, and the value of the sensing capacitance caused by most of the electromagnetic interference is larger, so that the value of the sensing capacitor is too small or too Large coordinate points can also function to reduce electromagnetic interference.

Embodiment 2:

5 is a second embodiment of an apparatus for resisting electromagnetic interference using the method of any of the present invention, the apparatus comprising:

a mobile terminal processor 30 for managing and controlling processing and interaction of data of the mobile terminal;

The capacitive screen chip 10 is configured to acquire capacitive touch panel sensing area data;

The determining module 20 is configured to determine whether the shape of the capacitive screen sensing area conforms to a preset regular shape;

The judging module may be integrated in the mobile terminal processor or may be separately set.

The device of the present invention adds a judging module for judging whether the shape of the capacitive screen sensing area conforms to a preset regular shape, so that the mobile terminal can sense the area data of the capacitive screen before the capacitive screen chip uploads the capacitive screen sensing area data. Screening is performed. If the sensing area of the capacitive screen is triggered by a finger, the shape of the obtained capacitive screen sensing area can be expected to be a predetermined regular shape such as an ellipse or a circle, and this part is reported. Point, the capacitive screen chip reports to the mobile terminal processor for processing; and in other cases, for example, if the capacitive screen receives electromagnetic interference, the shape of the capacitive screen sensing area formed by receiving electromagnetic interference is likely not a preset rule Shapes, if you do not report on this part of the situation, you can reduce the occurrence of jumps on the capacitive screen due to electromagnetic interference. Moreover, due to this mechanism, the capacitive screen can be reduced when performing anti-interference design. The situation of changing the capacitance of the capacitive screen appears, thereby ensuring the sensitivity of the capacitive screen, which not only improves the anti-interference ability of the capacitive screen, but also improves the touch sensitivity of the capacitive screen.

The above has described in detail the preferred embodiments of the invention. It will be appreciated that many modifications and variations can be made in the present invention without departing from the scope of the invention. Therefore, any technical solution that can be obtained by a person skilled in the art based on the prior art based on the prior art by logic analysis, reasoning or limited experimentation should be within the scope of protection determined by the claims.

Claims

A method for resisting electromagnetic interference of a capacitive screen, comprising the steps of:

Obtaining capacitive touch screen sensing area data; determining whether the shape of the capacitive screen sensing area conforms to a preset regular shape;

If it is met, the capacitive touch screen sensing area data is reported; if it is not, the report is not reported.
The method according to claim 1, wherein the step of determining whether the shape of the capacitive screen sensing area conforms to a preset regular shape comprises:

Determining whether the difference between the shape of the capacitive screen sensing area and the preset regular shape meets a preset threshold. If yes, determining that the shape of the capacitive screen sensing area conforms to a preset regular shape.
The method of claim 2, wherein the predetermined regular shape comprises at least a predetermined elliptical shape and a predetermined circular shape.
The method of claim 2, wherein the step of determining whether the shape of the capacitive screen sensing area conforms to a preset regular shape comprises:

A horizontal axis tangent line and a vertical axis tangent line are respectively performed on the capacitive screen sensing area, and it is determined whether the number of the capacitive channels spanned by the horizontal axis tangent line and the number axis tangent line meets a preset number. If yes, the difference value is determined to be less than or equal to the threshold value.
The method according to claim 1, wherein the step of determining whether the shape of the capacitive screen sensing area conforms to a preset regular shape comprises:

After the coordinate point of the capacitive sensing area in the sensing area of the capacitive screen is lower than the preset capacitance value, it is determined whether the shape of the capacitive sensing area conforms to a preset regular shape.
The method according to claim 1, wherein the step of determining whether the shape of the capacitive screen sensing area conforms to a preset regular shape further comprises the steps of:

Detecting whether the central capacitance sensing amount of the capacitive screen sensing area meets the preset sensing quantity threshold, and if yes, reporting the coordinate point.
The method according to claim 6, wherein the step of detecting whether the central capacitance sensing amount of the capacitive screen sensing area meets a preset sensing amount threshold comprises:

Extracting a coordinate point having the largest value of the sensing capacitance in the sensing area of the capacitive screen, and determining whether the value of the sensing capacitance of the coordinate point is greater than a preset sensing amount threshold. If it is greater than, determining that the central capacitance sensing quantity meets the preset sensing quantity threshold.
The method according to claim 6, wherein the step of detecting whether the central capacitance sensing amount of the capacitive screen sensing area meets a preset sensing amount threshold comprises:

Extracting a preset number of coordinate points having the largest value of the sensing capacitance in the sensing area of the capacitive screen, and determining whether the position of the coordinate point meets a preset spacing, if the distance between the coordinate points is within a preset spacing, Then, it is determined that the central capacitance sensing amount meets the preset sensing amount threshold.
The method of claim 8, wherein determining whether the sensing capacitance values of the predetermined number of all coordinate points are greater than a preset sensing amount threshold, if both are greater than, determining that the central capacitance sensing amount is consistent with the preset sensing Quantity threshold.
The method according to claim 1, wherein the capacitive screen sensing area is a continuous area on the capacitive screen that detects a change in capacitance, and if two or more capacitive screen sensing areas are detected simultaneously Then, it is determined whether the shape of each capacitive screen sensing area conforms to a preset regular shape.
Anti-electromagnetic interference device using the method according to any one of claims 1-10 The feature is that it includes:

a mobile terminal processor for managing and controlling processing and interaction of data of the mobile terminal;

a capacitive screen chip for acquiring capacitive screen sensing area data;

a judging module, configured to determine whether a shape of the capacitive screen sensing area conforms to a preset regular shape;

If yes, the determining module controls the capacitive screen chip to report the capacitive screen sensing area data to the mobile terminal processor; if not, the reporting is not performed.