CN109739385B - Method and device for touch finger identification based on capacitance signal and touch screen - Google Patents

Disclosure of Invention

The invention provides a method and a device for touch finger identification based on a capacitance signal and a touch screen, which can be used for improving poor touch effects, such as disconnection, jitter and the like, caused by small inter-finger distance or signal disturbance during multi-finger touch so as to improve the touch effects and user experience of touch products.

Based on the above object, the present invention provides a method for identifying a touch finger based on a capacitance signal, comprising:

acquiring capacitance distribution acquisition data when a touch screen is pressed by multiple fingers;

determining capacitance distribution data generated by the outer finger according to the fringe capacitance data in the acquired data;

and after the capacitance distribution data generated by the outer fingers are stripped from the collected data, identifying the middle finger for touch control.

Wherein, the outer side finger is specifically an upper/lower side finger; and

the determining capacitance distribution data generated by the outer finger according to the fringe capacitance data in the collected data specifically includes:

and according to the upper/lower edge capacitance data of the upper/lower side fingers in the collected data, obtaining capacitance distribution data generated by the upper/lower side fingers after the lower/upper edge capacitance data of the upper/lower side fingers are symmetrical.

Or, the outside finger is specifically a left/right side finger; and

the determining capacitance distribution data generated by the outer finger according to the fringe capacitance data in the collected data specifically includes:

and according to the left/right edge capacitance data of the left/right side fingers in the acquired data, obtaining capacitance distribution data generated by the left/right side fingers after the right/left edge capacitance data of the left/right side fingers are symmetrical.

Preferably, after acquiring the capacitance distribution data when the touch screen is pressed by multiple fingers, the method further includes:

carrying out Gaussian distribution expansion on the acquired data to obtain Gaussian distributed multi-finger capacitance data; and

the determining capacitance distribution data generated by the outer finger according to the fringe capacitance data in the collected data specifically includes:

determining outer finger capacitance data of Gaussian distribution according to the edge capacitance data in the multi-finger capacitance data of Gaussian distribution;

and carrying out reverse Gaussian processing on the capacitance data of the fingers at the outer sides of the Gaussian distribution to obtain the capacitance distribution data generated by the fingers at the outer sides.

The invention also provides a device for identifying the touch finger based on the capacitance signal, which comprises:

the capacitance signal acquisition module is used for acquiring capacitance distribution acquisition data when the touch screen is pressed by multiple fingers;

the outer finger capacitance distribution determining module is used for determining capacitance distribution data generated by the outer finger according to the edge capacitance data in the acquired data;

and the capacitance data stripping module is used for stripping capacitance distribution data generated by the outer fingers from the acquired data and then identifying the middle finger in touch control.

Further, the apparatus further comprises:

the Gaussian distribution expansion module is used for carrying out Gaussian distribution expansion on the acquired data to obtain Gaussian distributed multi-finger capacitance data; and

the outer finger capacitance distribution determining module is specifically configured to determine outer finger capacitance data in gaussian distribution according to the edge capacitance signal in the multi-finger capacitance data in gaussian distribution; and carrying out reverse Gaussian processing on the capacitance data of the fingers at the outer sides of the Gaussian distribution to obtain the capacitance distribution data generated by the fingers at the outer sides.

The present invention also provides a touch screen, comprising: the device for touch finger identification based on the capacitance signal is disclosed.

According to the technical scheme, after capacitance distribution acquisition data when a touch screen is pressed by multiple fingers is acquired, the capacitance distribution data generated by the fingers on the outer side can be determined according to the edge capacitance data in the acquisition data; and after capacitance distribution data generated by the outer fingers are stripped from the collected data, the method is favorable for more accurately identifying the touch fingers under the condition of small inter-finger distance or signal disturbance in multi-finger touch, particularly identifying the middle finger positioned between two outer fingers, and further obtaining a stable multi-finger working track.

Furthermore, in the technical scheme of the invention, Gaussian distribution expansion is carried out on the capacitance distribution acquisition data when the touch screen is pressed by multiple fingers, so that richer data details can be obtained, and the edge capacitance data analysis is facilitated; therefore, the capacitance distribution data generated by the outer finger can be more accurately determined; based on the more accurate capacitance distribution data generated by the outer fingers, the touch fingers can be identified more accurately, particularly the middle finger between the two outer fingers can be identified, and therefore a more stable multi-finger working track can be obtained.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative only and should not be construed as limiting the invention.

As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present. Further, "connected" or "coupled" as used herein may include wirelessly connected or wirelessly coupled. As used herein, the term "and/or" includes all or any element and all combinations of one or more of the associated listed items.

It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are used for distinguishing two entities with the same name but different names or different parameters, and it should be noted that "first" and "second" are merely for convenience of description and should not be construed as limitations of the embodiments of the present invention, and they are not described in any more detail in the following embodiments.

The inventor considers that the capacitance value generated by each finger touch influences the capacitance values of other fingers, and the capacitance signal generated by a single finger is stripped in limited capacitance signal information, so that the touch fingers can be more accurately identified under the condition of small inter-finger distance or signal disturbance in multi-finger touch, and the finger touch position can be further identified, and the stable multi-finger working track can be obtained.

The inventor of the present invention further considers that the distribution of capacitance value changes when each finger presses is actually distributed in a way that the upper and lower edges are substantially symmetrical, or the left and right edges are substantially symmetrical; therefore, after the fringe capacitance signal distribution data of the half of one finger is obtained, the fringe capacitance signal distribution data of the other half of the finger can be symmetrical, and the capacitance distribution data generated when the finger presses can be obtained. Therefore, after capacitance distribution acquisition data when the touch screen is pressed by multiple fingers is acquired, the capacitance distribution data generated by the fingers on the outer side can be determined according to the edge capacitance data in the acquisition data; and after capacitance distribution data generated by the outer fingers are stripped from the collected data, the method is favorable for more accurately identifying the touch fingers under the condition of small inter-finger distance or signal disturbance in multi-finger touch, particularly identifying the middle finger positioned between two outer fingers, and further obtaining a stable multi-finger working track.

The technical solution of the embodiments of the present invention is described in detail below with reference to the accompanying drawings. The present invention specifically provides the following two examples.

Example one

A method for identifying a touch finger based on a capacitive signal according to an embodiment of the present invention is specifically illustrated in fig. 5, and includes the following steps:

step S501: and acquiring capacitance distribution acquisition data when the touch screen is pressed by multiple fingers.

In this step, the distribution data of the capacitance signals generated by the multi-finger pressing, which is acquired when the touch screen is pressed by the plurality of fingers, is acquired, so that the capacitance distribution acquisition data when the touch screen is pressed by the plurality of fingers is acquired. As shown in fig. 6, the plurality of fingers pressing the touch screen may include outer pressing fingers, and may also include an intermediate pressing finger located between the two outer pressing fingers. For ease of description, the outer pressing finger will be referred to herein as the outer finger. For the case of multi-finger vertical scribe, the outside fingers may be fingers arranged on the upper and lower sides; for the case of multi-fingered horizontal-row scribing, the outer fingers may be fingers arranged on the left and right sides.

Step S502: and determining capacitance distribution data generated by the outer finger according to the edge capacitance data in the acquired capacitance distribution acquisition data.

In fact, the capacitance data distributed at the edge in the capacitance distribution acquisition data, i.e. the edge capacitance data, is often generated by the outer finger and is not influenced by the capacitance generated by pressing other fingers, so that the value of the edge capacitance is the capacitance distribution data which can be matched with the single finger; therefore, according to the capacitance distribution data generated by a single finger obtained by experience, the capacitance data which accords with the capacitance distribution data generated by the single finger can be used as the edge capacitance data from the capacitance distribution acquisition data when the touch screen is pressed by multiple fingers; therefore, in the step, the capacitance distribution data generated by the outer finger can be obtained after symmetrical processing is carried out according to the edge capacitance data.

Specifically, as shown in fig. 6, for the case of the multi-finger vertical line, when capacitance distribution data generated by the upper finger is determined, lower edge capacitance data of the upper finger may be obtained by symmetry according to upper edge capacitance data of the upper finger that is not interfered by capacitance signals generated by pressing of other fingers in the acquired capacitance distribution acquisition data, so as to obtain capacitance distribution data generated by the upper finger.

When the capacitance distribution data generated by the lower finger is determined, the capacitance distribution data generated by the lower finger can be obtained after the capacitance data of the upper edge of the lower finger is symmetrical according to the capacitance data of the lower edge of the lower finger which is not interfered by capacitance signals generated by pressing other fingers in the acquired capacitance distribution acquisition data.

Similarly, for the case of multi-finger horizontal line scribing, when capacitance distribution data generated by the left finger is determined, right edge capacitance data of the left finger can be symmetrically obtained according to left edge capacitance data of the left finger which is not interfered by capacitance signals generated by pressing of other fingers in the acquired capacitance distribution acquisition data, so that the capacitance distribution data generated by the left finger can be obtained.

When the capacitance distribution data generated by the right finger is determined, the left edge capacitance data of the right finger can be symmetrical according to the right edge capacitance data of the right finger which is not interfered by capacitance signals generated by pressing of other fingers in the acquired capacitance distribution acquisition data, so that the capacitance distribution data generated by the right finger can be obtained.

Step S503: and after the capacitance distribution data generated by the outer fingers are stripped from the acquired capacitance distribution acquisition data, identifying the middle finger in touch control.

Specifically, capacitance distribution data generated by the outer finger is stripped from acquired capacitance distribution acquisition data to obtain residual capacitance distribution data; for the same acquisition point, subtracting the capacitance data at the acquisition point from the capacitance data acquired at the point in the capacitance distribution data generated by the outer finger to obtain the residual capacitance data of the acquisition point.

Furthermore, because the residual capacitance distribution data removes the interference capacitance caused by the outer fingers to the middle finger, whether other fingers except the outer fingers press the touch screen can be more accurately judged based on the residual capacitance distribution data, and the specific identification method can adopt the existing identification method, for example, if the residual capacitance distribution data has a capacitance value larger than a threshold value and the area occupied by the capacitance value larger than the threshold value is larger than a set value, other fingers except the outer fingers press the touch screen can be identified; otherwise, judging that no other finger presses the touch screen. When the touch screen is judged to be pressed by other fingers, the middle finger in touch can be accurately identified, and the touch position of the finger can be further identified according to the peak value of the capacitance, so that a stable multi-finger working track is obtained.

In the technical scheme of the first embodiment of the invention, the capacitance value change distribution is actually distributed in a way that the upper edge and the lower edge are basically symmetrical or the left edge and the right edge are basically symmetrical when each finger is pressed; therefore, after the fringe capacitance signal distribution data of the half of one finger is obtained, the fringe capacitance signal distribution data of the other half of the finger can be symmetrical, and the capacitance distribution data generated when the finger presses can be obtained. Therefore, after capacitance distribution acquisition data when the touch screen is pressed by multiple fingers is acquired, the capacitance distribution data generated by the fingers on the outer side can be determined according to the edge capacitance data in the acquisition data; and then after capacitance distribution data generated by the outer fingers are stripped from the acquired data, the method is favorable for more accurately identifying the touch fingers under the condition of small inter-finger distance or signal disturbance in multi-finger touch, particularly identifying the middle finger of touch between the two outer fingers, and further obtaining a stable multi-finger working track.

Example two

The second method for identifying a touch finger based on a capacitive signal provided in the embodiment of the present invention has a specific process as shown in fig. 8, and includes the following steps:

step S801: and acquiring capacitance distribution acquisition data when the touch screen is pressed by multiple fingers.

In this step, the distribution data of the capacitance signals generated by the multi-finger pressing, which is acquired when the touch screen is pressed by the plurality of fingers, is acquired, so that the capacitance distribution acquisition data when the touch screen is pressed by the plurality of fingers is acquired. As shown in fig. 6, the plurality of fingers pressing the touch screen may include outer pressing fingers, and may also include an intermediate pressing finger located between the two outer pressing fingers. For ease of description, the outer pressing finger will be referred to herein as the outer finger. For the case of multi-finger vertical scribe, the outside fingers may be fingers arranged on the upper and lower sides; for the case of multi-fingered horizontal-row scribing, the outer fingers may be fingers arranged on the left and right sides.

Step S802: and performing Gaussian distribution expansion on the acquired capacitance distribution acquired data to acquire Gaussian distributed multi-finger capacitance data.

In order to clearly identify the fringe capacitance data in the subsequent step, data expansion may be performed on the acquired capacitance distribution collected data in this step to obtain richer data for analysis. For example, FIG. 9a shows a schematic diagram of a Gaussian distribution expansion of capacitance-by-capacitance data generated by a single finger; fig. 9b is a schematic diagram illustrating that the capacitance data of the outer finger with gaussian distribution is obtained after the gaussian distribution is extended to the acquired capacitance distribution data when the touch screen is pressed by multiple fingers. As can be seen from FIG. 9b, the data volume after expansion is 2-3 times of the original data volume, so that the details of the data are enriched, and the fringe capacitance data can be conveniently obtained in the subsequent steps.

Step S803: determining outer finger capacitance data of Gaussian distribution according to the edge capacitance data in the multi-finger capacitance data of Gaussian distribution; and carrying out reverse Gaussian processing on the capacitance data of the fingers at the outer sides of the Gaussian distribution to obtain the capacitance distribution data generated by the fingers at the outer sides.

In fact, because the capacitance data distributed at the edge in the capacitance distribution collected data, that is, the edge capacitance data, is often generated by the outer finger and is not affected by the capacitance generated by pressing of other fingers, the edge capacitance data in the capacitance distribution collected data can be matched with the capacitance distribution data generated by a single finger; similarly, the fringe capacitance data in the multi-finger capacitance data with gaussian distribution obtained after gaussian distribution expansion can be matched with the capacitance data obtained after gaussian distribution expansion of the capacitance distribution data generated for a single finger; therefore, according to the Gaussian-distributed single-finger capacitance data obtained by expanding the capacitance distribution data generated by a single finger through Gaussian distribution, the single-finger capacitance data conforming to the Gaussian distribution can be used as the edge capacitance data from the Gaussian-distributed multi-finger capacitance data; accordingly, in this step, capacitance data distributed at the edge, that is, edge capacitance data, is obtained from the gaussian-distributed multi-finger capacitance data, and after determining outer finger capacitance data of gaussian distribution according to the obtained edge capacitance data, inverse gaussian processing is performed on the outer finger capacitance data of gaussian distribution, so as to obtain capacitance distribution data generated by the outer finger.

For example, as shown in fig. 9b, the capacitance data of the upper edge of the upper finger in the gaussian-distributed multi-finger capacitance data is obtained after the capacitance data of the lower edge of the upper finger in the gaussian-distributed multi-finger capacitance data is symmetric according to the capacitance data of the upper edge of the upper finger in the gaussian-distributed multi-finger capacitance data; and performing reverse Gaussian processing on the capacitance data of the fingers on the upper side with the Gaussian distribution to obtain the capacitance distribution data generated by the fingers on the upper side.

According to the capacitance data of the lower edge of the lower finger in the Gaussian-distributed multi-finger capacitance data, after the capacitance data of the upper edge of the lower finger in the Gaussian-distributed multi-finger capacitance data is symmetrical, the capacitance data of the lower finger in the Gaussian distribution are obtained; and performing reverse Gaussian processing on the capacitance data of the lower side fingers with Gaussian distribution to obtain the capacitance distribution data generated by the lower side fingers.

Or, according to the left edge capacitance data of the left finger in the gaussian-distributed multi-finger capacitance data, after the right edge capacitance data of the left finger in the gaussian-distributed multi-finger capacitance data is symmetrical, the gaussian-distributed left finger capacitance data is obtained; and performing reverse Gaussian processing on the capacitance data of the fingers on the left side in Gaussian distribution to obtain the capacitance distribution data generated by the fingers on the left side.

According to the right edge capacitance data of the right finger in the Gaussian distribution multi-finger capacitance data, after the left edge capacitance data of the right finger in the Gaussian distribution multi-finger capacitance data is symmetrical, the Gaussian distribution right finger capacitance data is obtained; and performing reverse Gaussian processing on the capacitance data of the fingers on the right side in Gaussian distribution to obtain the capacitance distribution data generated by the fingers on the right side.

Step S804: and after the capacitance distribution data generated by the outer fingers are stripped from the acquired capacitance distribution acquisition data, identifying the middle finger in touch control.

Specifically, capacitance distribution data generated by the outer finger is stripped from acquired capacitance distribution acquisition data to obtain residual capacitance distribution data; furthermore, interference capacitance caused by the outer fingers to the middle finger is removed from the residual capacitance distribution data, so that whether other fingers except the outer fingers press the touch screen can be judged more accurately based on the residual capacitance distribution data. When other fingers press the touch screen, the middle finger in touch can be accurately identified, and the touch position of the finger can be further identified according to the peak value of the capacitance, so that a stable multi-finger working track is obtained.

Specifically, the outside finger capacitance distribution determining module 1003 may obtain the gaussian-distributed upper finger capacitance data after the upper edge capacitance data of the upper finger in the gaussian-distributed multi-finger capacitance data is symmetric according to the upper edge capacitance data of the upper finger in the gaussian-distributed multi-finger capacitance data; then, carrying out reverse Gaussian processing on the capacitance data of the upper side fingers with Gaussian distribution to obtain capacitance distribution data generated by the upper side fingers; or according to the capacitance data of the lower edge of the lower finger in the Gaussian-distributed multi-finger capacitance data, after the capacitance data of the upper edge of the lower finger in the Gaussian-distributed multi-finger capacitance data is symmetrical, the capacitance data of the lower finger in the Gaussian distribution is obtained; then, carrying out reverse Gaussian processing on the capacitance data of the lower side fingers with Gaussian distribution to obtain capacitance distribution data generated by the lower side fingers; or, according to the left edge capacitance data of the left finger in the gaussian-distributed multi-finger capacitance data, after the right edge capacitance data of the left finger in the gaussian-distributed multi-finger capacitance data is symmetrical, the gaussian-distributed left finger capacitance data is obtained; performing reverse Gaussian processing on the capacitance data of the fingers on the left side in Gaussian distribution to obtain capacitance distribution data generated by the fingers on the left side; or according to the right edge capacitance data of the right finger in the Gaussian-distributed multi-finger capacitance data, symmetrical out the left edge capacitance data of the right finger in the Gaussian-distributed multi-finger capacitance data, and then obtaining the Gaussian-distributed right finger capacitance data; and performing reverse Gaussian processing on the capacitance data of the fingers on the right side in Gaussian distribution to obtain the capacitance distribution data generated by the fingers on the right side.

In the second technical solution of the embodiment of the present invention, the capacitance value changes are distributed substantially symmetrically at the upper and lower edges or at the left and right edges when each finger is pressed; therefore, after the fringe capacitance signal distribution data of the half of one finger is obtained, the fringe capacitance signal distribution data of the other half of the finger can be symmetrical, and the capacitance distribution data generated when the finger presses can be obtained. Therefore, after capacitance distribution acquisition data when the touch screen is pressed by multiple fingers is acquired, the capacitance distribution data generated by the fingers on the outer side can be determined according to the edge capacitance data in the acquisition data; and after capacitance distribution data generated by the outer fingers are stripped from the collected data, the method is favorable for more accurately identifying the touch fingers under the condition of small inter-finger distance or signal disturbance in multi-finger touch, particularly identifying the middle finger positioned between two outer fingers, and further obtaining a stable multi-finger working track.

Furthermore, in order to obtain a more accurate recognition result, in the technical scheme of the second embodiment of the invention, Gaussian distribution expansion is also carried out on the capacitance distribution acquisition data when the touch screen is pressed by multiple fingers, so that richer data details can be obtained, and the edge capacitance data analysis can be conveniently carried out; therefore, the capacitance distribution data generated by the outer finger can be more accurately determined; based on the more accurate capacitance distribution data generated by the outer fingers, the touch fingers can be identified more accurately, particularly the middle finger between the two outer fingers can be identified, and therefore a more stable multi-finger working track can be obtained.

Those of skill in the art will appreciate that various operations, methods, steps in the processes, acts, or solutions discussed in the present application may be alternated, modified, combined, or deleted. Further, various operations, methods, steps in the flows, which have been discussed in the present application, may be interchanged, modified, rearranged, decomposed, combined, or eliminated. Further, steps, measures, schemes in the various operations, methods, procedures disclosed in the prior art and the present invention can also be alternated, changed, rearranged, decomposed, combined, or deleted.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the idea of the invention, also features in the above embodiments or in different embodiments may be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity. Therefore, any omissions, modifications, substitutions, improvements and the like that may be made without departing from the spirit and principles of the invention are intended to be included within the scope of the invention.