CN114546166A

CN114546166A - Method for avoiding micro-displacement misoperation of dragging action of capacitive touch screen

Info

Publication number: CN114546166A
Application number: CN202210145278.2A
Authority: CN
Inventors: 梁晨
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-09-14
Filing date: 2018-09-14
Publication date: 2022-05-27
Also published as: CN109164938B; CN109164938A

Abstract

The invention particularly relates to a method for avoiding micro-displacement misoperation of dragging action of a capacitive touch screen, wherein the touch screen comprises a controller and a processing unit, the controller calculates the contact position of a finger and a screen according to currents flowing out of four corner electrodes of the touch screen and outputs the contact position to the processing unit, and the processing unit carries out calibration processing according to the following steps: (A2) judging the current coordinate (x)_n,y_n) If the current coordinate is valid, outputting the current coordinate; if the coordinate is an invalid coordinate, executing the next step; (B2) judging the previous coordinate (x)_n‑1,y_n‑1) If it is valid, calibrating the coordinate (x) if it is valid_n‑m,y_n‑m) Outputting as the current coordinate; and if the coordinates are invalid, outputting the invalid coordinates. By monitoring the coordinates, when the invalid coordinates are output for the first time, the moment is the moment when the finger leaves the screen, and the invalid coordinates are calibrated to beThe coordinate value of the finger at the moment is stopped, so that the coordinate offset caused by the micro-displacement phenomenon is avoided, and the accuracy of the final touch position is ensured.

Description

Method for avoiding micro-displacement misoperation of dragging action of capacitive touch screen

Technical Field

The invention relates to the technical field of capacitive touch screen positioning, in particular to a method for avoiding micro-displacement misoperation of a dragging action of a capacitive touch screen.

Background

The capacitive touch screen technology works by using current induction of a human body. The capacitive touch screen is a four-layer composite glass screen, the inner surface and the interlayer of the glass screen are respectively coated with one layer of ITO, the outermost layer is a thin-layer silica glass protective layer, the ITO coating of the interlayer is used as a working surface, four electrodes are led out from four corners, and the ITO of the inner layer is used as a shielding layer to ensure a good working environment. When a finger touches the metal layer, a coupling capacitance is formed between the user and the touch screen surface due to the electric field of the human body, and for high frequency currents, the capacitance is a direct conductor, so that the finger draws a small current from the contact point. The currents respectively flow out of the electrodes on the four corners of the touch screen, the currents flowing through the four electrodes are in direct proportion to the distances from the fingers to the four corners, and the controller obtains the position of a touch point through accurate calculation of the proportion of the four currents. The capacitive touch screen is a latest input device, is the simplest, convenient and natural man-machine interaction mode at present, gives a brand-new appearance to multimedia, and is a brand-new multimedia interaction device with great attraction.

When operating on a device with a capacitive touch screen, such as a mobile phone or a tablet computer, a dragging micro-displacement phenomenon often occurs, for example: when the grenade is picked up and pulled away to be thrown to a position aimed in advance during a game, when the grenade is moved to the aimed position and then the fingers are loosened, small displacement is generated, and the grenade is thrown askew; when the drawing is repaired, a smearing tool is selected, and a region needing to be smeared is smeared by fingers, when the edge of the region is smeared by loose hands, the slight displacement is generated, and a little more smearing is always easy; when a video is edited, when a user pushes or pulls the time axis to a designated position and then releases his hand, a minute displacement is generated, and the time axis which is originally positioned is moved. Due to the existence of the dragging micro-displacement phenomenon, much inconvenience is brought to use, and therefore, how to eliminate the micro-displacement phenomenon is very important.

Disclosure of Invention

The invention aims to provide a method for avoiding micro-displacement misoperation of a dragging action of a capacitive touch screen, and improve the accuracy of touch control.

In order to realize the purpose, the invention adopts the technical scheme that: a method for avoiding micro-displacement misoperation of dragging action of a capacitive touch screen comprises a controller and a processing unit, wherein the controller calculates the contact position of a finger and a screen according to currents flowing out of four corner electrodes of the capacitive touch screen and outputs the contact position to the processing unit, and the processing unit performs calibration processing according to the following steps: (A2) judging the current coordinate (x)_n,y_n) If the current coordinate is valid, outputting the current coordinate; if the coordinate is an invalid coordinate, executing the next step; (B2) judging the previous coordinate (x)_n-1,y_n-1) If it is valid, the coordinates (x) will be calibrated if it is valid_n-m,y_n-m) Outputting as the current coordinate, wherein m is a set calibration value; and if the coordinates are invalid, outputting the invalid coordinates.

Compared with the prior art, the scheme has the following technical effects: by monitoring the coordinates, when the invalid coordinates are output for the first time, the moment is the moment when the finger leaves the screen, and the invalid coordinates are calibrated to be coordinate values when the finger stops at the moment, so that the coordinate offset caused by a micro-displacement phenomenon is avoided, and the accuracy of the final touch position is ensured.

Drawings

FIG. 1 is a plan view of a finger pointing down the screen and dragging to a loose hand.

Detailed Description

The present invention is described in further detail below with reference to fig. 1.

Fig. 1 is a plan projection view of a finger clicking a screen and dragging the finger to a loose hand, and it can be clearly seen from the figure that when the finger clicks the screen, the contact area between the finger and the screen gradually increases, when the finger drags on the screen, the contact area between the finger and the screen is basically constant, the position at which the finger stops is generally the last position that the user wants to determine, and the position is accurate, when the finger leaves the screen, the contact area between the finger and the screen gradually decreases, and a micro-displacement occurs in the process that the finger leaves the screen, so that the final position at which the finger completely leaves the screen and the position at which the finger stops are shifted, and the final positioning is not accurate enough.

In order to eliminate micro-displacement, the invention provides a method for avoiding micro-displacement misoperation of dragging action of a capacitive touch screen, wherein the capacitive touch screen comprises a controller and a processing unit, the controller calculates the contact position of a finger and a screen according to currents flowing out of four corner electrodes of the capacitive touch screen and outputs the contact position to the processing unit, and the processing unit carries out calibration processing according to the following steps: (A2) judging the current coordinate (x)_n,y_n) If the current coordinate is valid, outputting the current coordinate; if the coordinate is an invalid coordinate, executing the next step; (B2) judging the previous coordinate (x)_n-1,y_n-1) If it is valid, calibrating the coordinate (x) if it is valid_n-m,y_n-m) Outputting as the current coordinate, wherein m is a set calibration value; and if the coordinates are invalid, outputting the invalid coordinates. In the step a2 and the step B2, the output of the controller is valid coordinates when the finger is in contact with the screen, and the output of the controller is invalid coordinates when the finger is not in contact with the screen. In the previous scheme, invalid displacement is eliminated by monitoring the contact area, but the scheme is different, and errors caused by micro displacement are eliminated by correcting after each displacement.

In order to ensure the accuracy of the corrected coordinates, m is [ t1/t2], wherein t1 is the time difference between the moment when the finger stops and the moment when the finger completely leaves the screen, t2 is the coordinate output period of the controller, and [ t1/t2] is the rounding operation of the result of t1/t 2. Thus, it is ensured that the corrected coordinates are the coordinates at the moment when the finger stops. The correction process is explained below by means of a detailed example.

Assuming that the user presses the capacitive screen by a finger, the controller calculates the coordinates of the user pressing as { (5,5), (5,6), (5,7), (6,7), …, (45,74), (45,75), (45,76), (45,77), (-1, -1), (-1, -1), … }, where the first omitted point is a valid coordinate and the second omitted point is an invalid coordinate, and for convenience of description, all the invalid coordinates are replaced by (-1, -1), and all the valid coordinates are actual coordinate positions. In the prior art, the coordinates calculated by the controller are the output coordinates, which are then calibrated by steps a2 and B2.

In calibration, { (5,5), (5,6), (5,7), (6,7), …, (45,74), (45,75), (45,76), (45,77) } are output as the original coordinates, and when it is judged that the first (-1, -1) is an invalid coordinate, when it is judged that the coordinate (45,77) before the first (-1, -1) is an valid coordinate, when it is assumed that m takes 4, the coordinate (45,74) is output instead of (-1, -1), and when it is judged that the second and the following other (-1, -1) are output, the invalid coordinate (-1, -1) is output continuously, and therefore, the corrected coordinate is: { (5,5), (5,6), (5,7), (6,7), …, (45,74), (45,75), (45,76), (45,77), (45,74), (-1, -1), … }. When the finger stops, the coordinate of the finger is (45,74), although the micro-displacement phenomenon occurs in the process that the finger leaves the screen, namely the coordinate changes { (45,74), (45,75), (45,76), (45,77) }, after the finger leaves the screen finally, the first invalid coordinate after the finger leaves the screen is restored to the coordinate value (45,74) when the finger stops through correction, so that the error caused by the micro-displacement is eliminated, and the accuracy of finger touch is ensured.

Claims

1. A method for avoiding micro-displacement misoperation of a dragging action of a capacitive touch screen is characterized by comprising the following steps of: the capacitive touch screen comprises a controller and a processing unit, wherein the controller calculates the contact position of a finger and the screen according to the current flowing out of the four-corner electrodes of the capacitive touch screen and outputs the contact position to the processing unit, and the processing unit performs calibration processing according to the following steps:

(A2) judging the current coordinate (x)_n,y_n) If the current coordinate is valid, outputting the current coordinate; if the coordinate is an invalid coordinate, executing the next step;

(B2) judging the previous coordinate (x)_n-1,y_n-1) If it is valid, calibrating the coordinate (x) if it is valid_n-m,y_n-m) Outputting as the current coordinate, wherein m is a set calibration value; and if the coordinates are invalid, outputting the invalid coordinates.

2. The method for avoiding the micro-displacement misoperation of the dragging action of the capacitive touch screen as claimed in claim 1, wherein: in the step a2 and the step B2, the output of the controller is valid coordinates when the finger is in contact with the screen, and the output of the controller is invalid coordinates when the finger is not in contact with the screen.

3. The method for avoiding the micro-displacement misoperation of the dragging action of the capacitive touch screen as claimed in claim 1, wherein: and m is [ t1/t2], wherein t1 is the time difference between the moment when the finger stops and the moment when the finger completely leaves the screen, t2 is the coordinate output period of the controller, and [ t1/t2] is the rounding operation of the result of t1/t 2.