CN113220168B - Multi-mode operation method of capacitive touch panel - Google Patents

Abstract

The invention discloses a multi-mode operation method for a capacitive touch panel and a computing device, wherein the multi-mode operation method for the capacitive touch panel comprises the following steps: taking the mutual capacitance value of the panel at the initial time as a reference value; the mutual capacitance value obtained after the initial step is taken as an original value; comparing the original value with the reference value to obtain an induction value; comparing the current sensing value with the previous sensing value to obtain a first comparison result; a correction step, when the touch cell has an induction value smaller than 0 and the induction value of any one of the other touch cells in the vertical direction and the horizontal direction of the touch cell is larger than the effective touch standard value, obtaining a calculated value according to the induction value of the touch cell and the absolute value of the touch cell, and taking the calculated value as the induction value of the touch cell; and a determining step, selecting a normal mode or a waterproof mode according to the first comparison result and all the lattice sensing values after the correcting step.

Description

Multi-mode operation method of capacitive touch panel

Technical field

The present invention relates to the multi-mode operation of a capacitive touch panel, and in particular to the waterproof mode operation of a capacitive touch panel using mutual control scanning.

Background technique

Capacitive touch panels have been widely used in various electronic or computing devices, especially electronic devices such as mobile phones, tablet computers, and notebook computers. Capacitive touch panels often face extremely different operating environments. For example, water or highly conductive liquids are spilled on the touch pad, contaminants are attached, and so on. In order to solve these abnormal usage conditions, U.S. Patent US8823678 and Taiwan Patent TWI490764 respectively disclose methods for determining the location of water contamination. US Patent No. 8823678 is based on the measured capacitance levels in dry mode and wet mode to determine the presence or absence of contaminants. Taiwan Patent TWI490764 is based on the self-capacitance mode scanning method and compares the scanning signal results of different columns with each other to identify the location of water. However, existing technology only identifies areas affected by water but cannot discern whether these areas are effectively touched.

In addition, the existing technology cannot differentiate between contamination by highly conductive liquids such as salt water, resulting in low accuracy in determining the touched point.

Therefore, there is a need for capacitive touch panel technology that can reduce misjudgments and have a high reporting rate in a variety of different modes.

Contents of the invention

In order to provide technology that can accurately determine various operating modes and have a high reporting rate in various operating modes, the present invention proposes a multi-mode operating method for a capacitive touch panel. The panel has multiple touch points. The control grid uses mutual capacitance scanning to obtain a sensing value of the multiple touch grids, including a normal mode and a waterproof mode, and determines to enter the waterproof mode based on the following judgment of a waterproof condition: the multiple touch grids The maximum value of the sensing values is greater than an upper threshold, and the minimum value of the sensing values of the multiple touch grids is less than a lower threshold; the maximum value minus the minimum value of the sensing values of the multiple touch grids is greater than a first Predetermined value; among the sensing values of the plurality of touch cells, the total number of cells that are greater than the upper threshold is greater than the number of upper waterproof cells, and the total number of cells that are smaller than the lower threshold is greater than the number of lower waterproof cells; and all cells that are smaller than the lower threshold are The sum of the absolute values of the plurality of sensing values is greater than a second predetermined value. As long as two or more conditions are met, it will be determined that the waterproof mode is entered.

According to the concept of the present invention, the multiple sensing values preferably need to be judged to meet the above conditions more than twice before entering the waterproof mode.

According to the concept of the present invention, before performing the judgment, the plurality of sensing values will first undergo the following processing steps: when the panel is initialized, the sensing values of the mutual capacitance scan of each touch grid are obtained as the reference value of each touch grid. ; After that, each time the sensing value of the mutual capacitance scan of each touch grid is obtained, the sensing value is deducted from the reference value of each touch grid, and then the waterproof condition is determined.

According to the concept of the present invention, before performing the judgment, the multiple sensing values will be corrected first. When the touch grid has a sensing value less than 0, and in other touch grids in the vertical and horizontal directions of the touch grid, When the sensing value of any touch grid is greater than an effective touch standard value, and when the sensing value of any other touch grid in the horizontal direction of the touch grid is greater than the effective touch standard value, the The sensing value of the touch grid and the absolute value of the touch grid obtain a calculated value as the sensing value of the touch grid.

According to the concept of the present invention, if a touch event is detected, the upper threshold value, the lower threshold value, the first predetermined value, the upper waterproof grid number, the lower waterproof grid number, and the second waterproof grid number in the judgment waterproof condition are The predetermined value or the value of the number of judgments can increase with the number of touch events.

According to the concept of the present invention, after entering the waterproof mode, it includes a determination of a water-free condition to return to the normal mode. The water-free condition is the same as the standard for judging the waterproof condition, or the upper threshold and the lower threshold can be reduced. , the first predetermined value, the upper waterproof grid number, the lower waterproof grid number or the second predetermined value form a buffering effect.

The present invention also proposes a multi-mode operation method for a capacitive touch panel. The panel has a plurality of touch grids, and a sensing value of the multiple touch grids is obtained by mutual capacitance scanning, including a normal mode. And a waterproof mode, and in the waterproof mode, for an area that is not determined to be touched, if there is a change in the sensing amount, it is regarded as a change caused by water, and a waterproof reference value is established accordingly. The sensing of each touch grid After deducting the waterproof reference value from the numerical value, the touch effect is then judged.

According to the concept of the present invention, in the waterproof mode, a waterproof mode effective touch standard value is set to be greater than a normal mode effective touch standard value in the normal mode, and according to the sensed value is greater than the waterproof mode effective touch standard value The sensing values of the upper, lower, left and right adjacent touch cells of the standard value touch cell set a surrounding judgment condition to determine whether the touch cell is effectively touched.

According to the concept of the present invention, in the waterproof mode, when a touch event is not determined to occur, the effective touch standard value of the waterproof mode can be increased, or the standard of the surrounding judgment conditions can be increased. After a touch event occurs, return to The original waterproof mode effective touch standard value, or return to the original standard for judging conditions around the environment.

According to the concept of the present invention, in the waterproof mode, when the total number of sensing values of the plurality of touch grids that are greater than an upper threshold is greater than a number of positive area grids or the total number of values that are smaller than a lower threshold is greater than a number of negative area grids, When the amount is greater than the number of changes in an area, you can increase the effective touch standard value of the waterproof mode, or increase the standard of the surrounding judgment conditions.

According to the concept of the present invention, in the waterproof mode, when it is determined that a touch event occurs, a protection range is set around a touch coordinate. Within this protection range, stable processing is strengthened, the reporting standard is improved, or forced limitation will not occur. New touch events.

According to the concept of the present invention, in the waterproof mode, the effective touch standard value of the touch grid on the edge of the touch panel is set to be smaller than the waterproof effective touch standard value, or the touch panel at the corner of the touch panel is set to be smaller than the waterproof effective touch standard value. The effective touch standard value of the touch grid is set to be greater than the waterproof effective touch standard value. According to the touch grid whose sensing value is greater than the waterproof mode effective touch standard value, the top, bottom, left and right adjacent to the touch grid are The sensing value of the touch grid is used to determine whether the touch grid is effectively touched; or the filtering or stabilization processing is enhanced for the sensing value of each touch grid to improve the stability of the touch effect.

According to the concept of the present invention, in the waterproof mode, after it is determined that the touch object causes a touch event, if the touch object leaves the touch panel within a predetermined period of time, the operation is forced to stay in the waterproof mode, or If the difference between the current sensing value and the previous sensing value is greater than the predetermined value and the total number of touch cells is greater than a predetermined number of cells, the waterproof mode will remain in the waterproof mode for a predetermined period of time but no effective touch judgment will be performed.

The present invention also proposes a multi-mode operating method for a capacitive touch panel. The panel has a plurality of touch grids, and a sensing value of the multiple touch grids is obtained by mutual capacitance scanning, including a normal mode. And an underwater operation mode, and use an underwater switch setting or enter the underwater operation mode based on the following judgment of underwater conditions: the change amount of the sensing values of the multiple touch grids increased in a short period of time is greater than an effective Touch standard value, and the sensing values of the multiple touch grids remain stable within a preset time; in addition, after it is determined that the underwater operation mode is entered, an underwater reference value is established, and the multiple touch The sensing value of the control grid takes an absolute value or a negative value and then makes a touch judgment.

According to the concept of the present invention, the method further includes a waterproof mode, in which the underwater operation mode can be entered according to the underwater switch setting or the underwater condition determination.

According to the concept of the present invention, after it is determined that the underwater operation mode has been entered, the sensing values of the multiple touch grids can be further amplified or the judgment criteria can be relaxed when making touch judgments, wherein the method of relaxing the judgment criteria includes an underwater mode valid The touch standard value is set to be less than a normal mode effective touch standard value in the normal mode, or according to the upper, lower, left and right adjacencies of the touch grid whose sensing value is greater than the underwater mode effective touch standard value. The sensing value of the touch grid lowers the standard value of the surrounding judgment conditions to determine whether the touch grid is effectively touched.

According to the concept of the present invention, after it is determined that the water operation mode has been entered, it is also determined to leave the water operation mode according to the following conditions for leaving the water, and return to the waterproof mode or the normal mode: the sensing values of the multiple touch grids are within a short period of time. The total change amount decreased within a time period is greater than a water determination value, and the total change amount of the sensing values of the plurality of touch grids within a preset time period is less than a stable preset value.

The present invention also proposes a computing device, including: a central processing unit; a touch panel for display and allowing the user to operate in a touch mode; and a controller that communicates with the touch panel and the central processing unit. , or have the function of judging a touch effect based on a touch sensing value; wherein the central processing unit and the controller cooperate to perform the aforementioned methods.

According to the present invention, the negative touch effect and the adhesion of contaminants can be distinguished, the effective touch can still be accurately identified when the touch screen is stained with a large amount of water, and the liquid with high conductivity attached to the touch panel can be distinguished from the one worn on the touch screen. In the case of glove touch, it has a much higher effective touch recognition capability compared to the existing technology.

Description of drawings

Figure 1 is a schematic view showing a mutual capacitance touch panel;

Figures 2A and 2B respectively show examples of the sensing values of each touch grid when a normal finger touches the panel and the sensing values of each touch grid when water exists on the touch panel;

Figure 3 is a flow chart for illustrating mutual capacitance signal processing according to an embodiment of the present invention;

Figure 4 is a flow chart for illustrating tracking and negative touch effect processing according to an embodiment of the present invention;

Figure 5 shows numerous grid sensing values of the touch panel to illustrate the negative touch effect;

Figure 6 is a flow chart to illustrate the "waterproof mode" judgment and processing operations;

Figure 7 is a block diagram illustrating a computing device according to an embodiment.

Explanation of reference signs: 500-computing device; 502-touch panel; 504-controller; 506-central processing unit.

Detailed ways

In order to help understand the spirit and principle of the present invention, the arrangement and sensing method of the capacitive touch panel will be briefly described. Referring to FIG. 1 , the touch panel 100 is provided with N columns and M rows of scan lines. In this specification, the area between two adjacent rows and two adjacent columns is called a grid, and the entire touch panel is called a frame. Generally speaking, a capacitive touch panel generates an induced electric field on the surface of the panel to obtain an equivalent capacitance value. When a finger touches, the intensity of the induced electric field changes and the equivalent capacitance value also changes. Generally speaking, the change magnitude is about pF (10 ^-12 Farads), the signal thus obtained will be converted into a digital signal by a device such as an analog-to-digital converter and subjected to other processing to generate corresponding values for use in performing different processes or operations. Generally speaking, there are two main scanning methods for scanning a touch panel to obtain sensing values. One is self-capacitance scanning and the other is mutual capacitance scanning. The present invention mainly uses mutual capacitance scanning to obtain sensing values.

Here, the capacitive sensing value of the capacitive touch panel under the induced electric field is called raw data. The capacitive sensing value will also be different under different environmental conditions such as contact and attachment of foreign objects. The original data obtained under the initial conditions without being touched or contacted by foreign objects is referred to as the baseline value below. The original value is obtained when the finger touches the capacitive touch panel. The difference value of this original value minus the reference value is the change value caused by the finger touch, that is, the difference value = original value - reference value. For example, FIG. 2A shows the change magnitude of each touch grid when a finger is touched under normal circumstances, that is, the values shown in the figure are all difference values. As shown in Figure 2A, the value of the grid with a value of 1197 and its surrounding grids are significantly larger than other touch grids, and thus are regarded as finger touches. In the following, the change value will be called the sensing value.

Generally speaking, the operation modes of touch panels mainly include normal mode and waterproof mode. The waterproof mode refers to the operating mode when water exists on the touch panel. The operating modes other than this mode are the normal modes.

FIG. 3 is a flow chart illustrating mutual capacitance signal processing 100 according to the present invention. As shown in Figure 3, in step S100, at the beginning of booting, the entire touch panel is scanned in the mutual capacitance mode to obtain the mutual capacitance value signal, and the signal is subjected to A/D processing and other processing to obtain the corresponding value as a reference value. . For example, in a clean environment and without foreign objects touching, the obtained reference value of each touch grid will be within a certain range, for example, within ±30. Then proceed to step S102.

In step S102, the entire touch panel is scanned in a mutual capacitance manner to obtain a mutual capacitance value signal, and the signal is subjected to A/D processing and other processing to obtain a corresponding value as an original value. Then, in step S104, the original value is subtracted from the reference value, and the difference value (=original value-reference value) is obtained as the current sensing value for subsequent processing. Generally speaking, it enters the normal operating mode after initial startup. For example, in the case where the entire touch panel has 28x16 grids, the effective touch standard value (or standard value for short) is preset to 400, that is, when the value of the grid is greater than or equal to 400, it will be regarded as being effectively touched. control. If the touch panel enters normal mode after being turned on, the maximum sensing value at the finger touch is 1200.

According to an embodiment of the present invention, the sensing value obtained as above will undergo tracking and negative touch effect processing 200 for mode judgment and mode processing. As shown in Figure 4, in S202, tracking processing is performed to compare the current sensing value of each touch grid with the previous sensing value. The comparison result can provide touch point information on the touch panel and so on. For example, based on the comparison results, you can know whether a new touch event occurs and the movement trajectory of touch objects such as fingers.

The negative touch effect means that when two or more fingers touch the touch surface and create more than two touch points, negative sensing values will be generated between these effective touch points. This effect is called the negative touch effect. When it is found that a touch event occurs and the values of some cells are negative according to the comparison results of tracking processing, negative touch effect processing will be performed. For example, as shown in Figure 5, there are two touch points (multiple cells shown by the darkest shadow in the figure), and the values of many cells in the box are negative values. These negative values are due to negative effects. Caused. However, some grids will have negative values due to being affected by pollutants. Therefore, in order to avoid negative touch effects being judged as pollutants, negative touch effect processing will be performed on grids with negative values. In step S206, it is determined whether the grid is affected by the negative touch effect. If the grid sensing value is less than the effective touch standard value and the touch grid has grids greater than the standard value in both the vertical and horizontal directions, the touch grid is considered to be affected by the negative touch effect. For example, the grid with -153 in Figure 5 corresponds to the negative touch effect. If the determination result is yes, continue to step S208.

In step S208, the current value of the touch grid is replaced with the value calculated by the following formula:

C _cal =C+(|C|－|N _offset |)/R

Among them, C _cal : negative effect calculation value, C: grid value, N _offset : negative touch effect offset, R: scale value.

Therefore, the value of the -153 grid will become -153+(|-153|-|90|)/2≈-132 after processing. In this way, before the waterproof mode condition is judged, grids affected by the negative touch effect will not be mistakenly judged as contaminated points, further increasing the judgment accuracy.

According to an embodiment of the present invention, the sensing values after the above tracking and negative touch effect processing will be provided to the mode judgment processing and/or each mode processing.

Next, mode determination and related mode processing according to embodiments of the present invention are described. First, the "waterproof mode" determination and processing operations according to the embodiment of the present invention will be described. Waterproof mode refers to the situation when water exists on the touch panel.

FIG. 6 is a flow chart illustrating the "waterproof mode" determination and processing operation 300. In step S302, based on the touch panel sensing value after tracking and negative touch effect processing, it is first determined whether there is water on the touch panel to determine whether to maintain the normal mode, enter the waterproof mode, or switch from the waterproof mode. Switch to normal mode. If it is determined that there is water on the touch panel, it will enter waterproof mode. Otherwise, it will remain in normal mode or switch from waterproof mode to normal mode. For example, if the following five conditions are met, it will be judged as the presence of water and enter the waterproof mode: 1. The largest value among the possessive sensing values of the touch panel is greater than the upper waterproof threshold, such as 200, or The minimum value is less than the lower waterproof threshold, for example -200; 2. (Maximum cell sensing value) - (Minimum cell sensing value) > predetermined value, such as 300; 3. The sensitivity of individual cells in the possessive cell sensing value The total number of cells with measured values greater than the upper waterproof threshold (for example, 200) is greater than the number of upper waterproof cells (for example, >4 cells), and the total number of cells with measured values less than the lower threshold (for example, -180) is more than the number of lower waterproof cells (for example, >8 cells). ); 4. The sum of the absolute value of each touch grid sensing value minus the waterproof offset value (for example, 200) among the possessive grid sensing values that is less than the lower threshold (for example, -180) is greater than the predetermined value (for example, >420). For example, the sum of the induction values of the four cells marked in the larger bold box in Figure 2B is (|-259|+|-370|+|-226|)>420; 5. Scan all cells at least twice in a row Sensing value, meeting the above conditions 1 to 4 at the same time. It is worth noting that preferably, each of the above thresholds, offset values or predetermined values may depend on the size, number of grids and other characteristics of the touch panel. If the above five conditions are met, that is, the water condition is met, continue to step S304 to enter the waterproof mode operation.

In step S304, an effective touch standard value higher than that in the normal mode is set. For example, in normal mode operation, the effective touch standard value is set to 400, but in waterproof mode, the effective touch standard value is set to 600. In addition, according to embodiments of the present invention, in order to accurately determine the situation of water accumulation at the edges and corners of the touch panel and reduce misjudgments, the effective touch standard values of the touch grids at the edges and corners of the touch panel are set to be equal to Other touch grids are different. For example, when the effective touch standard value of other touch grids is set to 600, the effective touch standard value of the touch grid on the edge of the touch panel is lowered, for example, to 550, and the touch standard value of the touch grid in the corner is set to 600. The effective touch standard value of the grid is further increased, for example, 700. In this way, false positives of valid touch points can be avoided. Then, proceed to step S306.

In step S306, it is determined whether the touch grid is effectively touched based on the comparison of the sensing values of the possible touched grid and its surrounding neighboring grids with valid touch standards and multiple preset thresholds. For example, it is determined whether the sensing value of the potentially touched cell is greater than the effective touch standard value (for example, 600) and whether it is greater than or equal to the sensing values of all adjacent cells (up, down, left, and right). Here, the surrounding adjacent cells refer to the vertically and horizontally adjacent cells of the touch cell. For example, the cells in the top row and below have only 3 adjacent cells, and the center cell has 4 adjacent cells. grid and so on. Next, it is determined whether the values of the adjacent cells of the touch cell are all greater than 0, whether the sum of the upper and lower adjacent cells is greater than a first predetermined threshold (for example, 600), and whether the sum of the values of the left and right adjacent cells is greater than a second predetermined threshold (for example, 600). For example, 600) or the sum of the up, down, left, and right is greater than the third predetermined threshold (for example, 900). If it matches, the touch grid will be determined to be effectively touched, and the touch result will not be output until it is determined to be effectively touched. For example, as shown in Figure 2B, although the cell with a sensing value of 603 marked by a smaller thick frame is greater than the effective touch standard value, the value of its right neighbor is -193, which does not meet the condition that all neighbors are greater than 0. , so it will not be judged as a valid touch. It should be understood that the above-mentioned standard values or related thresholds used for judgment are only examples, and they may differ depending on conditions such as the spacing between columns and rows. For example, the relevant threshold may be determined based on a large amount of measurement data.

In addition, when determining the existence of valid touch points, when the distance between the two finger touch points is within 6 grids, only the touch point with a large sensing amount is left, and the other point is ignored. Furthermore, in order to avoid the water on the touch panel being pushed away by the touch object after the touch object touches the touch panel, causing a misjudgment in determining whether there is water in step S302, and switching from the waterproof mode to the normal mode, Before step S302 determines that there is no water and prepares to switch from the waterproof mode to the normal mode, it will first be judged whether to leave the waterproof mode (S308). When it is already in the waterproof mode before step S302, it is judged that the touch object causes After a touch event, if the touch object leaves the touch panel for a predetermined period of time, it will still be forced to stay in the waterproof mode, or if the difference between the current sensing value and the previous sensing value is greater than the predetermined value. When the total number of control grids is greater than a predetermined number of grids, it will still remain in the waterproof mode for a predetermined period of time but will not perform effective touch judgment. In other words, if the conditions for determining that there is no water in step S302 are met, the following two items will be determined: 1. Determining whether it is in waterproof mode before entering step S302; 2. The difference between the current sensing value and the previous sensing value Whether the total number of touch cells greater than the predetermined value is greater than a predetermined number of cells. When any one of the above two items is met, even if it is determined to be an anhydrous state in step S302, the waterproof mode will still be maintained for a predetermined period of time without directly switching to the normal mode, and step S304 will then be performed. Otherwise, leave the waterproof mode and directly switch to the normal mode, and then proceed to step S306.

In step S308, it is determined whether to leave the waterproof mode. The judgment conditions in this step will be more stringent than the conditions for judging entering waterproof mode to avoid frequent switching between two different modes in boundary conditions. For example, assuming that the touch pad has a value of 0 when there is no water at all, and a value of 100 when there is a lot of water and cannot be operated, a certain threshold for judging whether to enter waterproof mode is set to 80, and then leave. A certain threshold in waterproof mode is set to 60. After entering waterproof mode, when the value is between 60 and 80, it will still operate in waterproof mode.

In addition, when the finger is lifted after being determined to be touched, it will remain in the waterproof mode for at least a period of time, such as 0.5 seconds, and still perform effective touch point identification processing. Alternatively, when the difference between the sensing value and the previous sensing value is greater than the predetermined change value and the total number of divisions is greater than, for example, the predetermined number of divisions equivalent to the width of the thumb, such as 2 divisions, then the system remains in the waterproof mode for at least a period of time, such as 0.5 seconds, but no valid touch point recognition processing is performed.

When it is determined in step S308 that the waterproof mode is left, it will return to the normal mode; otherwise, it will return to step S306.

In this embodiment, for determining whether to leave the waterproof mode and return to the normal mode in step S308, there are the following five conditions. If the conditions are met, it will be determined to leave the waterproof mode and return to the normal mode: 1. Touch panel possessive case The largest value among the sensing values is greater than the upper waterproof threshold, such as 150, or the smallest value is less than the lower waterproof threshold, such as -150; 2. (Maximum grid sensing value) - (Minimum grid sensing value) > predetermined value , such as 210; 3. The total number of cells where the sensing value of individual cells in the possessive sensing value is greater than the upper waterproof threshold (for example, 150) is more than the number of upper waterproof cells (for example, >3 cells) and is smaller than the lower threshold (for example, -150 ) is more than the number of lower waterproof cells (for example, >6 cells); 4. The absolute value of the sensing value of each touch cell in all cells that is less than the lower threshold (for example, -150) minus the waterproof offset value ( The sum of (e.g. 150) is greater than a predetermined value (e.g. >420). For example, the sum of the induction values of the four cells marked in the larger bold box in Figure 2B is (|-259|+|-370|+|-226|)>420; 5. Scan all cells at least twice consecutively Sensing value, meeting the above conditions 1 to 4 at the same time. It is worth noting that preferably, each of the above thresholds, offset values or predetermined values may depend on the size, number of grids and other characteristics of the touch panel. If the above five conditions are met, that is, the conditions for leaving the waterproof mode and returning to the normal mode are met, then the normal mode operation will be entered.

As mentioned above, the operation modes of the touch panel mainly include normal mode and waterproof mode. The waterproof mode refers to the operating mode when water exists on the touch panel. The operating modes other than this mode are the normal modes. According to the present invention, as long as a small amount of water exists on the touch panel, it will enter the waterproof mode. Although when the entire screen is immersed in water, it can also be broadly regarded as the presence of water on the touch panel, but if you look closely, there are still differences between the two. To be more clear, when only a small amount of water exists on the touch panel, it can be judged to be water stains or damaged based on the comparison between the sensing value of the surrounding adjacent cells and the effective touch standards and multiple preset thresholds. Effective touch. However, when the screen is completely immersed in water, all the touch grids on the screen will be in a state of water, causing the overall sensing value to increase. In this state, even if a finger touches the screen, its sensing value The increased amount of change will become relatively small, making it difficult to clearly judge and detect. Therefore, the present invention sets an additional underwater mode for the state where the screen is completely immersed in water. Unlike when a small amount of water exists on the touch panel, the sensing value of the touch grid touched by water stains or fingers will increase significantly due to the pressure. When the screen is completely immersed in water, because all the touch grids on the screen are In a state where there is water, when your finger slides on the touch panel, the water on the touch panel will be pushed away, which will cause the sensing value of the touched touch grid to decrease, so it can be used to determine whether it is a valid touch. .

The underwater mode can be set through an underwater switch or whether to enter the underwater mode is determined based on the following conditions: the change in the sensing value of the touch grid in a short period of time is greater than an effective touch standard value and the touch The sensor value of the grid remains stable within a preset time (for example, 0.5 seconds). After determining that the water mode has been entered, the system will establish a water reference value, and then perform a touch judgment based on the absolute value or negative value of the sensing value of the touch grid.

Since the sensing values of all the touch grids on the screen will increase as a whole when the screen is immersed in water, in order to effectively determine the finger touch after entering the underwater mode, the sensing values of the touch grids can be set again. Zoom in or set an additional relaxed judgment standard when performing touch judgment. The method of relaxing the judgment standard includes: setting the effective touch standard value of an underwater mode to be smaller than a normal mode effective touch standard value in a normal mode, or based on the sensed value being greater than the effective touch standard value of the underwater mode. The upper, lower, left and right sensing values of the touch grid adjacent to the touch grid set the standard value of the surrounding judgment conditions to decrease to determine whether the touch grid is effectively touched.

After it is determined that it has entered the underwater mode, you can leave the underwater mode and return to the waterproof mode or normal mode according to the following judgment: the total change in the sensing value of the touch grid decreased in a short period of time is greater than the underwater judgment value, and the touch The total change amount of the grid's sensing value within a preset time is less than a stable preset value.

Compared with the existing technology, according to the present invention, the situation of misjudgment can be significantly reduced and the accuracy of effective touch control can be greatly improved. When there is a considerable amount of water, the waterproof mode of the prior art often misjudges or cannot be executed. However, the waterproof mode according to the present invention can still correctly determine the effective touch.

Figure 7 is a block diagram showing a computing device 500 according to one embodiment. As shown in the figure, the computing device 500 includes a touch panel 502, a controller 504, and a central processing unit 506. The touch panel 502 is used for display and allowing the user to perform touch operations. The controller 506 can obtain an input signal from the touch panel, and can cooperate with the central processing unit 508 to execute at least one of the above-mentioned multiple modes according to the present invention according to the input signal. The computing device 500 is capable of performing waterproof mode processing according to the present invention with high touch point accuracy.

Although the preferred embodiments of the present invention have been described above, these are for illustrative purposes only and should not be construed as limiting the scope of the present invention. Without departing from the spirit of the present invention, those skilled in the art may Many modifications may be made, and the claims cover all such modifications as fall within the scope and spirit of the invention.

Claims (19)

1. A multi-mode operation method for a capacitive touch panel is characterized in that the panel is provided with a plurality of touch cells, an induction value of the plurality of touch cells is obtained in a mutual capacitance scanning mode, the operation mode of the touch panel comprises a normal mode and a waterproof mode, and the touch panel is determined to enter the waterproof mode according to one of the following judging waterproof conditions:

(1) The maximum value of the sensing values of the plurality of touch cells is larger than an upper threshold value, and the minimum value of the sensing values of the plurality of touch cells is smaller than a lower threshold value;

(2) The maximum value minus the minimum value in the sensing values of the plurality of touch cells is larger than a first preset value;

(3) The total number of the sensing values of the plurality of touch control grids, which is larger than the upper threshold value, is larger than an upper waterproof grid number, and the total number of the sensing values, which is smaller than the lower threshold value, is larger than a lower waterproof grid number; and

(4) The absolute value sum of all the sensing values smaller than the lower threshold is larger than a second preset value;

and (3) if two or more of the conditions (1) to (4) are met, judging that the waterproof mode is entered.

2. The multi-mode operation method for a capacitive touch panel according to claim 1, wherein the waterproof mode is entered when the plurality of sensing values are judged to be in accordance with the conditions described in (1) to (4) of claim 1 twice or more.

3. The method of claim 1, wherein the sensing values are processed as follows before performing the determining:

when the panel is initially, the sensing value of each touch cell mutual capacitance scanning is obtained as a reference value of each touch cell; and

And then obtaining the sensing value of each touch cell mutual capacity scanning every time, deducting the sensing value from the reference value of each touch cell, and then executing the waterproof judgment condition.

4. The method of claim 1, wherein the plurality of sensing values are corrected before the determination is performed, and when the sensing value of the touch cell has a sensing value smaller than 0, and the sensing value of any one of the other touch cells in the vertical direction and the horizontal direction of the touch cell is larger than an effective touch standard value, and the sensing value of any one of the other touch cells in the horizontal direction of the touch cell is larger than the effective touch standard value, a calculated value is obtained according to the sensing value of the touch cell and the absolute value of the touch cell to be used as the sensing value of the touch cell.

5. The method of claim 1, wherein the values of the upper threshold, the lower threshold, the first predetermined value, the upper number of waterproof cases, the lower number of waterproof cases, or the second predetermined value in the waterproof condition are increased with the number of touch events if a touch event is detected.

6. The method of claim 2, wherein the upper threshold, the lower threshold, the first predetermined value, the upper number of waterproof cases, the lower number of waterproof cases, the second predetermined value, or the number of judgment times in the judgment waterproof condition increases with the number of touch events if a touch event is detected.

7. The method of claim 1, wherein after entering the waterproof mode, a judging anhydrous condition is included, wherein the judging anhydrous condition is the same as the standard of the judging waterproof condition, or the upper threshold, the lower threshold, the first predetermined value, the upper waterproof number, the lower waterproof number or the second predetermined value is reduced to form a buffering effect.

8. The method according to claim 1, wherein in the waterproof mode, after a touch event is determined by a touch object, the touch object is forcedly left in the waterproof mode for a predetermined time after leaving the touch panel, or when the total number of touch cells having a difference between a current sensing value and a previous sensing value greater than a predetermined value is greater than a predetermined number of cells, the touch object is left in the waterproof mode for a predetermined time without performing effective touch judgment.

9. The method of claim 1, wherein in the waterproof mode, if there is a change in the sensing amount for an area not determined to be touched, the change is regarded as a change caused by water, and a waterproof reference value is established accordingly, and after the sensing value of each touch cell is subtracted from the waterproof reference value, a touch effect is determined.

10. The method of claim 9, wherein in the waterproof mode, a waterproof mode effective touch standard value is set to be greater than a normal mode effective touch standard value in the normal mode, and a surrounding judgment condition is set according to sensing values of upper, lower, left and right adjacent touch cells of the touch cell whose sensing value is greater than the waterproof mode effective touch standard value, so as to judge whether the touch cell is effectively touched.

11. The method of claim 10, wherein in the waterproof mode, when the touch event is not determined to occur, the effective touch standard value of the waterproof mode is increased, or the standard of the surrounding determination condition is increased, and after the touch event occurs, the original effective touch standard value of the waterproof mode is returned, or the original standard of the surrounding determination condition is returned.

12. The method of claim 10, wherein in the waterproof mode, when a difference between a total number of the sensing values of the plurality of touch cells greater than an upper threshold and a positive area cell number is greater than an area change cell number or a difference between a total number of the sensing values of the plurality of touch cells less than a lower threshold and a negative area cell number is greater than an area change cell number, the waterproof mode effective touch standard value is increased or the surrounding judgment condition standard is increased.

13. The method of claim 9, wherein in the waterproof mode, when it is determined that a touch event occurs, a protection range is set around a touch coordinate, and the protection range is used to enhance a stabilization process, improve a reporting standard, or force a definition that no new touch event occurs.

14. The multi-mode operation method for capacitive touch panel according to claim 10, wherein in the waterproof mode, an effective touch standard value of a touch cell at an edge of the touch panel is set smaller than the waterproof mode effective touch standard value, or an effective touch standard value of the touch cell at a corner of the touch panel is set larger than the waterproof mode effective touch standard value, and whether the touch cell is effectively touched is judged according to an induction value of the touch cell with a sensing value larger than the waterproof mode effective touch standard value, wherein the upper, lower, left and right adjacent to the touch cell; or the filtering or stabilizing treatment is enhanced aiming at the sensing numerical value of each touch cell, so that the stability of the touch effect is improved.

15. The method of claim 1, wherein the operation modes of the touch panel include the normal mode and an underwater operation mode, and the underwater operation mode is entered by a underwater switch setting or according to a determination underwater condition as follows:

the change amount of the sensing values of the plurality of touch cells in a short time is larger than an effective touch standard value, and the sensing values of the plurality of touch cells in a preset time are stable;

in addition, after the underwater operation mode is judged, an underwater reference value is established, and the sensing values of the plurality of touch control grids take absolute values or take negative values to carry out touch control judgment.

16. The method of claim 15, wherein the entering into the underwater operation mode is determined according to the underwater switch setting or the underwater condition determination in the waterproof mode.

17. The method according to claim 15 or 16, wherein after determining that the in-water operation mode is entered, the sensing values of the plurality of touch cells are further amplified or the determination criteria are relaxed when performing touch determination, wherein the method of relaxing the determination criteria includes setting an in-water mode valid touch criterion value to be smaller than a normal mode valid touch criterion value in the normal mode, or setting a decrease in the criterion value of surrounding determination conditions according to the sensing values of the touch cells adjacent to the up, down, left and right of the in-water mode valid touch criterion value to determine whether the touch cell is valid.

18. The multi-mode operation method for a capacitive touch panel according to claim 15 or 16, wherein after determining to enter the in-water operation mode, the out-of-water operation mode is additionally determined according to the following determination out-of-water conditions, and returns to the waterproof mode or the normal mode:

the total variation of the sensing values of the plurality of touch cells in a short time is larger than a water judgment value, and the total variation of the sensing values of the plurality of touch cells in a preset time is smaller than a stable preset value.

19. A computing device, comprising:

a central processing unit;

a touch panel for displaying and allowing a user to operate in a touch manner;

the controller is communicated with the touch panel and the central processing unit or has the function of judging a touch effect according to a touch sensing value;

wherein the central processing unit and the controller operate cooperatively to perform the method of claim 1.