TW201447705A - Method for testing a capacitive touch apparatus, capacitive touch apparatus testing device and capacitive touch apparatus - Google Patents

Abstract

A method for testing a capacitive touch apparatus includes sequentially driving M sets of electrodes on the first dimension and N sets of electrodes on the second dimension to detect a capacitive touch apparatus, in which M and N are natural numbers. Two or more electrodes in the same set should be tested simultaneously. According to the testing result of each set on the first dimension and the second dimension, for a touch position, coordinate information of the first dimension and that of the second dimension are calculated separately so as to determine a possible touch position. This invention further provides an apparatus corresponding to the method mentioned above. This invention provides a technical solution which can eliminate the interference from power sources and calculate the exact touch position.

Description

Capacitive touch device detection method and device and capacitive touch device

The present invention relates to the field of touch device technologies, and in particular, to a capacitive touch device detection method and device, and a capacitive touch device.

Capacitive touch device detection solutions, including self-capacitance and mutual capacitance. The self-capacitance detection scheme detects the capacitance of the electrode to ground in the touch device. The detecting circuit sends a scanning signal through the electrode, and receives a feedback signal from the same electrode, and calculates the magnitude of the capacitance to the ground according to the magnitude of the feedback signal. If a touch event occurs on the current electrode, since the capacitance between the human body and the ground is large, and the human body can be nearly equivalent to a ground, the current electrode to ground capacitance will increase; as shown in Fig. 1, Cp represents the current electrode. The initial capacitance to ground, Cf represents the capacitance of the current electrode to the human body, and the current capacitance to ground is the parallel connection of Cp and Cf. Therefore, if the detection circuit detects that the capacitance to the ground increases, it can be determined that the current electrode has touched; and according to the change of the capacitance of each electrode to the ground, the specific position at which the touch occurs can be calculated. The mutual capacitance detection scheme is to output a scan signal through one electrode while receiving a scan signal through another electrode, thereby calculating two electrodes. The size or variation of the capacitance.

Fig. 2 shows a common touch screen structure, in which the X-axis direction includes electrodes such as T1, T2, ..., T16, and electrodes in the Y-axis direction R1, R2, ..., R10. Assume that the detection shows that the capacitance to ground of T13, T14, T15 and R3, R4, R5 has changed, then the X-axis coordinates of the touch position can be obtained by the magnitude of the capacitance change on T13, T14, T15, through R3, R4, The size of the capacitance change on R5 can be used to derive the Y-axis coordinate.

A commonly used solution in the prior art is that the detection circuit switches through the switch to detect the capacitance to the ground of each electrode on the touch device in a time-sharing manner, and the currently unscanned electrode is grounded or suspended. When a poor quality charger is connected to the system where the touch device is located, the system will have noise corresponding to the real earth, that is, the so-called power supply interference. The human body that the detection circuit sees as a reference is a noise. The source and the noise are coupled to the detecting circuit through the capacitance between the human body and the electrode. At this time, the capacitance value detected by the detecting circuit is inaccurate.

Since the detection of each electrode in the prior art is time-divisionally processed, the power supply interference of the different electrodes at the time of detection is irrelevant, and then, when the touch position is calculated, the power supply interference cannot be eliminated, resulting in the calculated touch. The location will be inaccurate, unlike the actual touch location.

The embodiments of the present invention provide a capacitive touch device detection method and device, and a capacitive touch device to solve the technical problem that the existing touch device is inaccurate due to power supply interference.

The first aspect of the invention provides a capacitive touch device inspection The measuring method comprises: sequentially driving the M group electrode in the first dimension and the N group electrode in the second dimension to perform detection, wherein M and N are both natural numbers, and two or more electrodes included in any group of electrodes are simultaneously Performing detection; calculating first and second dimensional coordinate data of the touch position according to the detection results of the groups of electrodes in the first and second dimensions, respectively, to determine a set of possible touch positions.

A second aspect of the present invention provides a capacitive touch device detection apparatus, including: a first detection module, configured to sequentially drive M groups of electrodes in a first dimension and N sets of electrodes in a second dimension for detection, wherein And N are both natural numbers, and the two or more electrodes included in any group of electrodes are simultaneously detected; the calculation module is configured to calculate the touch position according to the detection results of the electrodes in the first and second dimensions respectively. The first and second dimensional coordinate data determine a set of possible touch locations.

The invention also provides a capacitive touch device comprising: the device as described above.

The embodiment of the invention adopts a technical solution that the electrodes of the touch device are divided into a plurality of groups, and the plurality of electrodes of each group are simultaneously detected, and in the case of power supply interference, the detection results of the plurality of electrodes in the same group are The power interference component is related and has a certain correlation relationship. Then, in the subsequent calculation, the power interference can be eliminated by a certain algorithm to calculate an accurate touch position.

10‧‧‧channel electrode

20‧‧‧

T1-T16‧‧‧X-axis direction electrode

R1-R10‧‧‧Y-axis electrode

A11-a96‧‧‧Electrode change (commonly known as mutual capacitance)

B1-b15‧‧‧ capacitance to ground (commonly known as self-capacitance)

210‧‧‧First detection module

220‧‧‧Computation Module

230‧‧‧Second test module

Figure 1 is a schematic diagram of detecting capacitance to ground when a touch event occurs; 2 is a schematic diagram of a common touch screen structure; FIG. 3 is a flow chart of a method for detecting a capacitive touch device according to an embodiment of the present invention; and FIG. 4 is a schematic diagram of a capacitive touch screen structure; 5 is a schematic diagram of multi-touch; FIG. 6 is a schematic diagram of a mutual capacitance scanning technology; and FIG. 7 is a schematic diagram of a capacitive touch device detecting apparatus according to an embodiment of the present invention.

Embodiments of the present invention provide a capacitive touch device detection method and apparatus, and a capacitive touch device, which can eliminate the influence of power supply interference and calculate an accurate touch position. Embodiments of the present invention also provide corresponding devices. The details will be described in detail below with reference to the accompanying drawings.

Embodiment 1

Referring to FIG. 3, an embodiment of the present invention provides a method for detecting a capacitive touch device, comprising: 110, sequentially driving M groups of electrodes in a first dimension and N groups of electrodes in a second dimension, wherein M and N is a natural number, and two or more electrodes included in any group of electrodes are simultaneously detected.

In this embodiment, the electrodes in each dimension of the touch device are divided into groups to be detected by groups. Taking the capacitive screen structure shown in FIG. 4 as an example, the device includes two electrodes arranged in two dimensions, and has 16 electrodes in the first dimension, that is, the X-axis direction, respectively, with T1, T2, ..., T16 In the second dimension, that is, the Y-axis direction, there are 10 electrodes, which are respectively identified by R1, R2, ..., R10.

In one embodiment, the 16 electrodes in the X-axis direction may be divided into the following groups: the first group includes T1 to T6, the second group includes T5 to T10, the third group includes T9 to T14, and the fourth group includes T13. To T16; 10 electrodes in the Y-axis direction can be divided into the following groups: the fifth group includes R1 to R6, and the sixth group includes R6 to R10. In the above grouping manner, one or several electrodes between two adjacent groups in each dimension are simultaneously included in two groups. Other grouping methods are also possible in other embodiments, and are not described herein again.

In this embodiment, the detection is performed according to the determined grouping, and two or more electrodes included in one set of electrodes are driven to be simultaneously detected in one period; in the next period, two or more electrodes included in the next group of electrodes are simultaneously driven. Test; until the test is completed. The detecting adopts a self-capacitance detecting scheme, comprising: driving a group of electrodes to emit a scanning signal, and receiving a feedback signal through the group of electrodes.

120. Calculate the first and second dimension coordinate data of the touch location according to the detection results of the groups of electrodes in the first and second dimensions, respectively, to determine a set of possible touch locations.

Assuming that the touch occurs at the intersection of the T4 electrode and the R8 electrode, after several sets of electrodes in the X-axis direction are sequentially detected, it can be found that the capacitance of the T4 electrode changes to the maximum, and the pair of electrodes T3 to T5 on both sides thereof The ground capacitance also changes, and the coordinate data of the touch position in the X-axis direction, such as T4, can be calculated according to the capacitance changes of T3, T4, and T5. with The coordinates of the touch position in the Y-axis direction, for example, R8, can be calculated from the capacitance changes of R7, R8, and R9. In turn, it is possible to determine the position of T4, R8 at which the touch position occurs.

In the above detection scheme, since the electrodes T3, T4 and T5 belong to the same electrode group and are simultaneously detected, in the case of power supply interference, the power interference component is correlated in the detection data of T3, T4 and T5. Therefore, when calculating the X-axis coordinate data, the influence of the power interference component can be eliminated according to a conventional calculation method, thereby calculating accurate X-axis coordinate data. Similarly, the electrodes R7, R8 and R9 also belong to the same electrode group, and the influence of the power interference component can be eliminated according to a conventional calculation method, thereby calculating an accurate Y-axis coordinate data.

In the following, the principle of how to eliminate power interference is further described. In the case of no power interference, when the touch occurs, the coordinate calculation is based on the amount of data change detected by each electrode, and the size is formed by the capacitance formed by the human body and each electrode. In proportion, it is assumed that the amount of change of each electrode is A1, A2, A3, ... An. In the case of power disturbance, the detection circuit is referenced to the system ground. At this time, the human body is equivalent to a noise source, and the noise is coupled to the electrode through the capacitance of the human body and each electrode. In the case where a group of electrodes proposed in the present embodiment are simultaneously detected, since the noise source is the same, and the amplitude is also proportional to the capacitance of the human body and the electrode, it can be found that the noise size is proportional to the amount of change caused by the touch, and the ratio is assumed. The coefficient is k, and the amount of change caused by the noise is kA1, kA2, kA3, ... kAn, where k changes with time. Therefore, although the power noise interference components applied to the electrodes are not equal, at the same time The ratio of the disturbance applied to each electrode to the amount of change caused by the human touch is the same, so that the influence of the power supply disturbance on each electrode can be offset according to a certain algorithm.

In summary, the above method for detecting the electrode grouping can ensure that the electrode at the touch position and at least one of the electrodes adjacent thereto are simultaneously detected, and the power supply interference noise of the electrodes is related, so that a certain calculation method can be adopted. Overcome the effects of power disturbances and calculate the exact touch location. In order to ensure that the electrode at the touch position and each of the electrodes on both sides thereof can be simultaneously detected to further improve the anti-interference ability, it is preferable to simultaneously divide one or more electrodes of the most edge of each group into adjacent groups when grouping. In another group, the edge electrodes of each group were repeatedly scanned. In order to save the electrode or reduce the number of scans, the edge electrodes of each group do not need to be repeatedly scanned, which can reduce the detection circuit, but reduce the anti-interference ability of the area where these edge electrodes are located.

In one embodiment, driving a set of electrodes for detecting comprises: driving the set of electrodes to emit a scan signal, and receiving a feedback signal through the set of electrodes, and simultaneously driving all other electrodes except the set of electrodes to emit the same scan signal, but The other electrodes described do not receive the feedback signal. For example, as shown in FIG. 4, while driving the fifth group of electrodes R1 to R6 to emit a scanning signal, all other electrodes can be driven to emit the same scanning signal, but only the fifth group of electrodes R1 to R6 receive the feedback signal, and the other electrodes are Do not receive feedback signals. The scanning method does not interfere with the detection of the fifth group of electrodes R1 to R6 on the one hand, and the scanning waveform of each electrode on the entire touch device is uniform on the other hand, and there are water drops on the surface of the touch device. In the case of foreign matter, interference such as water droplets can be avoided. The principle of avoiding water bead interference is: when the scanning waveforms of the respective electrodes are the same, the voltages of the electrodes at the current scanning electrode and the water droplets change at the same time, so that the measurement of the capacitance to the ground is not affected. The detection scheme of this embodiment may be referred to as a full screen common mode scanning scheme.

In the case that the touch device supports multi-touch, the set of touch positions determined in step 120 may include more than two. Please refer to Figure 5, assuming that the actual touch occurs at the two positions T4, R8 and T13, R3, then the above detection scheme can detect T4, T13 and R3, and R8 has the largest change in capacitance to ground, and the determined possible touch The position may be two points of T4, R8 and T13, R3, or two points of T4, R3 and T13, R8, and may also be the above four points. This detected touch position does not conform to the actual touch position, and there is a problem of a false touch position, which is called a "ghost point" problem.

In one embodiment, in order to solve the "ghost point" problem, in the case where the set of possible touch positions determined in step 120 includes more than two, the method may further include the following steps: 130, performing again using mutual capacitance scanning technology Detecting, determining another set of possible touch locations, comparing the two sets of possible touch locations obtained, excluding false touch locations, and determining an accurate touch location.

The mutual capacitance scanning technology can drive one electrode to emit a scanning signal while receiving the scanning signal through the other electrode, and calculate the magnitude or change of the capacitance between the two electrodes by the received signal. This mutual capacitance scanning technology enables true multi-touch control. In this embodiment, the upper The detecting by using the mutual capacitance scanning technology includes: driving all the electrodes in the first dimension to sequentially emit the scanning signals, and sequentially passing the N groups of electrodes in the second dimension in a period in which the scanning signals are sent by any one of the electrodes in the first dimension. A scan signal is received, wherein two or more electrodes included in any one of the electrodes in the second dimension simultaneously receive the scan signal. Of course, all the electrodes in the second dimension may not be grouped, but as a group, and when any one of the first dimension electrodes emits a scan signal, the scan signal is simultaneously received.

The above-mentioned mutual capacitance scanning is further described by taking FIG. 6 as an example. In the figure, the electrodes T1-T9 (transverse electrodes) in the Y-axis direction sequentially emit scanning signals, so that only one Y-axis electrode emits a scanning signal in the same period. The X-axis electrodes are divided into groups as described above, and only the first group of electrodes R1-R6 (longitudinal electrodes) are shown. During the period in which the Y-axis emits a scanning signal, the X-axis groups of electrodes sequentially receive the scanning signals, but the same group includes two or more electrodes that simultaneously receive the scanning signals. For example, when the electrode T1 sends a scanning signal, the first group of electrodes R1- R6 simultaneously receives the scan signal and detects six capacitors C1.1, C1.2, ... C1.6 between the electrode T1 and the electrodes R1-R6. Thus, after the detection is completed, q*p capacitors can be obtained, where q and p represent the number of electrodes in the X-axis and Y-axis directions, respectively.

Please refer to Figure 5, assuming that the actual touch occurs at the two positions T4, R8 and T13, R3, it can be measured that the two capacitors C4.8 and C13.3 have changed greatly, so that T4, R8 can be determined. And T13, R3 is the touch position. Finally, comparing steps 120 and 130 with two sets of possible touch positions determined by the two techniques, it is possible to eliminate spurious touch positions such as T4, R3 and T13, R8, and determine an accurate touch position, such as T4, R8 and T13, R3.

It can be seen that the present embodiment can solve the "ghost point" problem by repeatedly detecting by using the mutual capacitance scanning technology, thereby determining an accurate touch position.

In summary, the embodiment of the present invention provides a method for detecting a capacitive touch device, which adopts a technique of dividing electrodes in multiple dimensions of a touch device into multiple groups, and simultaneously detecting multiple electrodes of each group. In the case of power supply interference, the power interference component in the detection results of multiple electrodes in the same group is related, and in the subsequent calculation, the power interference can be eliminated by a certain algorithm to calculate an accurate touch position. . Further, while a group of electrodes is being detected, driving all other electrodes simultaneously to emit the same scan signal but not detecting can overcome the problem of water droplet interference. Further, when a certain set of possible touch positions includes more than two, the mutual detection by the mutual capacitance scanning technology can solve the "ghost point" problem.

Embodiment 2

Referring to FIG. 7 , an embodiment of the present invention provides a capacitive touch device detection device, including: a first detection module 210 for sequentially driving M groups of electrodes in a first dimension and N groups of electrodes in a second dimension. Detection, wherein M and N are both natural numbers, and two or more electrodes included in any group of electrodes are simultaneously detected; and a calculation module 220 is configured to detect each group of electrodes according to the first and second dimensions As a result, the first and second of the touch position are respectively calculated Dimension coordinates data to determine a set of possible touch locations.

The first detecting module 210 can be specifically configured to drive a group of electrodes to send a scanning signal, and receive the feedback signal through the group of electrodes that send the scanning signal; and simultaneously drive all the electrodes except the group of electrodes to emit the same signal. Scan the signal. The first detecting module 210 may include: a scanning unit for driving a group of electrodes to emit a scanning signal; and a receiving unit for receiving a feedback signal by the group of driving electrodes that emit the scanning signal.

In an embodiment, the device may further include: a second detecting module 230. In the present manner, the second detecting module 230 is detected by using a mutual capacitance scanning technology; the computing module 220 is further used. And determining another set of possible touch positions according to the detection result of the second detection module, comparing two sets of possible touch positions obtained by the first and second detection modules, excluding false touch positions, and determining an accurate touch position.

The second detecting module 230 can be specifically configured to drive all the electrodes in the first dimension to sequentially send out scanning signals, and pass through the second dimension in a period in which the scanning signal is sent by any one of the electrodes in the first dimension. The N sets of electrodes sequentially receive the scan signals, wherein the set of electrodes included in the second dimension includes two or more electrodes that simultaneously receive the scan signals. The second detecting module 230 may include: a scanning unit for driving one electrode to emit a scanning signal; and a receiving unit for receiving a scanning signal through a group of electrodes.

The capacitive touch device detection device provided in this embodiment is briefly described above. For a more detailed description, please refer to the description in the first embodiment. Contained content.

On the basis of the capacitive touch device detecting device, the embodiment of the present invention further provides a touch device including the device.

In summary, an embodiment of the present invention provides a capacitive touch device and a detection device thereof, which divide electrodes in multiple dimensions of a touch device into a plurality of groups, and multiple electrodes of each group are simultaneously detected. In the case of power supply interference, the power interference component in the detection results of multiple electrodes in the same group is related, and in the subsequent calculation, the power interference can be eliminated by a certain algorithm to calculate an accurate touch position. Further, while a set of electrodes is being tested, the device can drive all other electrodes to simultaneously emit the same scan signal without detecting, thereby overcoming the problem of water droplet interference. Further, in the determined set of possible touch positions including more than two, the device can be detected again by mutual capacitance scanning technology, thereby solving the "ghost point" problem.

A person skilled in the art can understand that all or part of the steps of the foregoing embodiments may be implemented by hardware, or may be implemented by a program instruction related hardware, and the program may be stored in a computer readable storage medium. The storage medium may include: read only memory, random read memory, magnetic disk or optical disc.

The capacitive touch device detection method and device and the capacitive touch device provided by the embodiments of the present invention are described in detail above, but the description of the above embodiments is only for helping to understand the method and the core idea of the present invention, and should not It is understood to be a limitation of the invention. Those skilled in the art can easily think of changes or within the scope of the technology disclosed by the present invention. Alternatives are intended to be covered by the scope of the present invention.

110‧‧‧   sequentially driving the M sets of electrodes in the first dimension and the N sets of electrodes in the second dimension, wherein M and N are both natural numbers, and the two or more electrodes included in any set of electrodes are simultaneously performed Detection

120‧‧‧ According to the detection results of the groups of electrodes in the first and second dimensions, respectively calculating the first and second dimensional coordinate data of the touch position to determine a set of possible touch positions

130‧‧‧Re-detection using mutual capacitance scanning technology to determine another set of possible touch positions, compare the two possible touch positions obtained, eliminate false touch positions, and determine the exact touch position

Claims (9)

A method for detecting a capacitive touch device includes: sequentially driving M groups of electrodes in a first dimension and N groups of electrodes in a second dimension, wherein M and N are natural numbers, and any group of electrodes includes The two or more electrodes are simultaneously detected; and according to the detection results of the groups of electrodes in the first and second dimensions, the first and second dimensional coordinate data of the touch position are respectively calculated to determine a set of possible touch positions. The method of claim 1, driving the M sets of electrodes in the first dimension and the N sets of electrodes in the second dimension in sequence for detecting comprises: driving a set of electrodes to emit a scan signal, and receiving a feedback signal through the set of electrodes; It also drives all other electrodes except the set of electrodes to emit the same scan signal. The method of claim 1 or 2, if the determined set of possible touch locations comprises more than two, the method further comprises: performing another detection using a mutual capacitance scanning technique to determine another set of possible touch locations; The two sets of possible touch locations obtained are compared to exclude spurious touch locations and to determine an accurate touch location. The method of claim 3, wherein the detecting by using the mutual capacitance scanning technology comprises: driving all the electrodes in the first dimension to sequentially emit a scanning signal, and in the first dimension, the time period in which the one of the electrodes emits the scanning signal passes the first The N sets of electrodes in the second dimension sequentially receive the scan signal, wherein the second dimension The two or more electrodes included in any set of electrodes at the same time receive the scan signal simultaneously. A capacitive touch device detecting device includes: a first detecting module, configured to sequentially drive M groups of electrodes in a first dimension and N sets of electrodes in a second dimension, wherein M and N are natural numbers The two or more electrodes included in any group of electrodes are simultaneously detected; the calculation module is configured to calculate the first and second touch positions respectively according to the detection results of the groups of electrodes in the first and second dimensions Dimension coordinates data to determine a set of possible touch locations. The device of claim 5, wherein the first detecting module is specifically configured to drive a group of electrodes to send a scanning signal, and receive a feedback signal through the group of electrodes that send the scanning signal; and simultaneously drive the group of electrodes other than the group of electrodes. All other electrodes emit the same scan signal. The device of claim 5 or 6, comprising: a second detecting module, configured to perform the detecting again by using a mutual capacitance scanning technology; and the calculating module is further configured to determine another according to the detection result of the second detecting module A set of possible touch locations that compare the two sets of possible touch locations obtained, eliminating false touch locations and determining an accurate touch location. The device of claim 7, wherein the second detecting module is specifically configured to drive all the electricity in the first dimension The scan signal is sequentially emitted, and the scan signals are sequentially received by the N sets of electrodes in the second dimension during a period in which the scan signal is emitted by any one of the electrodes in the first dimension, wherein any set of electrodes in the second dimension includes Two or more electrodes simultaneously receive the scan signal. A capacitive touch device comprising: the device of any one of claims 5 to 8.