KR102092664B1 - Circuit and method for selecting coordinates in differential touch sensing system - Google Patents

Abstract

The present invention discloses a coordinate selection circuit and method of a differential touch sensing system that differentially senses a change in capacitance due to a touch, converts differential values of a portion where a change in the differential signal is detected to accumulated values, and stores the accumulated values A first detection unit outputting first detection information according to the fields; A second detection unit which outputs second detection information according to the differential values; A water detection unit that outputs a selection signal as a result of determining whether water is detected by comparing the first detection information and the second detection information; And a coordinate selector for selecting one of the first coordinates corresponding to the accumulated values and the second coordinates corresponding to the differential values by the selection signal and selecting and outputting the coordinates corresponding to the touch. It is characterized by.

Description

Coordinate selection circuit and method of differential touch sensing system {CIRCUIT AND METHOD FOR SELECTING COORDINATES IN DIFFERENTIAL TOUCH SENSING SYSTEM}

The present invention relates to a differential touch sensing system, and more particularly, to a coordinate selection circuit and method of a differential touch sensing system for differentially sensing a change in capacitance due to touch.

Recently, a display panel composed of a mobile device or the like employs a lot of touch functions.

In this case, most display panels are implemented as flat panel display devices such as liquid crystal displays, and the touch function is implemented as a touch panel combined with a display panel.

The touch panel means a transparent switch panel having a function of operating a device or executing a program according to a user pressing a text, an image or an icon.

The touch panel may be configured to perform capacitive touch recognition, and as an example of a touch panel that implements capacitive touch recognition, a "mutual capacitance touch sensing device" is disclosed as "US Patent Publication No. US 2009/0091551". have.

In general, a touch sensing system may be implemented to sense in a differential manner in order to detect a correction capacity.

When the sensing signal is driven in a differential manner, the touch sensing system is resistant to noise and can be expected to improve the touch sensitivity and the accuracy of sensing.

During the use of the touch panel, water may remain on the touch surface, in which case water may be recognized as a touch due to a change in electrostatic capacity.

The conventional differential touch sensing system has difficulty in accurately sensing the finger touch by excluding the water region by accurately distinguishing the water region from the water touch, which is a general touch, when water is present due to the characteristics of the differential signal.

Therefore, the conventional touch sensing system needs to be improved to accurately distinguish a finger touch, which is a general area, from a water area, and for this, it is necessary to present a method for avoiding water characteristics.

An object of the present invention is to provide a coordinate selection circuit and method of a differential touch sensing system capable of obtaining accurate coordinates corresponding to a touch by avoiding water characteristics when water is present in the touch panel.

In addition, the present invention converts a differential value sensing a portion changed by a touch into a value insensitive to a water characteristic (for example, an accumulated value) to obtain coordinates corresponding to a water region when water is present on the touch panel. Another object is to provide a coordinate selection circuit and method for a differential touch sensing system that can be obtained.

The coordinate selection circuit of the differential touch sensing system according to the present invention includes: a first detection unit that converts differential values of a portion where a differential signal is changed into accumulated values and outputs first detection information according to the accumulated values; A second detection unit which outputs second detection information according to the differential values; A water detection unit that outputs a selection signal as a result of determining whether water is detected by comparing the first detection information and the second detection information; And a coordinate selector for selecting one of the first coordinates corresponding to the accumulated values and the second coordinates corresponding to the differential values by the selection signal and selecting and outputting the coordinates corresponding to the touch. It is characterized by.

In the coordinate selection method of the differential touch sensing system according to the present invention, differential values of touch sensing data, which are sensing data of a portion in which sensing changes are obtained among sensing data obtained by differentially sensing a change in capacitance due to touch, are accumulated values. Converting; Providing a first labeling value counting the number of positions above a preset first threshold value for the accumulated values; Providing a second labeling value counting the number of positions equal to or greater than a second preset threshold value for the differential values; Calculating and providing first coordinates corresponding to each location counting the first labeling value; Calculating and providing a second coordinate corresponding to each location counting the second labeling value; Outputting a selection signal by detecting the presence of water using at least two of the accumulation value, the differential value, the first labeling value, the second labeling value, the first coordinates, and the second coordinates; And selecting and outputting one of the first coordinates and the second coordinates as coordinates corresponding to the touch by the selection signal.

According to the present invention, when water is present in the touch panel, water characteristics can be avoided to obtain accurate coordinates corresponding to the touch.

In addition, according to the present invention, by converting the differential value sensing the portion changed by the touch into an accumulation value, it is possible to obtain coordinates corresponding to a normal touch in the presence of water as an accumulation value insensitive to water characteristics.

Therefore, the present invention can be expected to have an effect of improving touch sensitivity and sensing accuracy in response to a case where water is strong and resistant to noise due to water characteristics.

1 is a circuit diagram showing a preferred embodiment of the coordinate selection circuit of the differential touch sensing system according to the present invention.
2 is a waveform diagram illustrating the conversion of differential values to accumulated values.
3 is a waveform diagram representing differential values to contrast a finger touch and a touch that recognizes the presence of water.
4 is a waveform diagram corresponding to a state in which the differential values in FIG. 3 are converted into accumulation values.
5 is a raw data map that illustrates differential values and accumulation values recognizing a finger touch.
6 is a raw data map illustrating differential values and accumulation values recognizing the presence of water.
7 is a diagram illustrating a method of recognizing a finger touch when water is not present on the touch panel.
8 is a diagram for explaining a method of recognizing a finger touch when water is present on the touch panel.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The terms used in the present specification and claims are not interpreted as being limited to ordinary or dictionary meanings, and should be interpreted as meanings and concepts consistent with the technical matters of the present invention.

The embodiments illustrated in the specification and the drawings shown in the specification are preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention, and various equivalents and modifications that can replace them at the time of this application It can be.

The coordinate selection circuit and method of the differential touch sensing system according to the present invention discloses a technique for excluding a water region and sensing a general touch to obtain coordinates when water is sensed like a normal touch due to the presence of water on the touch panel. .

In particular, the differential touch sensing system according to the present invention converts a differential value of a portion in which a differential signal due to a touch occurs to an accumulated value that is insensitive to water characteristics, and filters a sensing value that recognizes the presence of water while responding to general sensing. Disclosed is a technique for obtaining coordinates.

In the present invention, general sensing means normal sensing using a finger or a separate device (for example, a touch pen).

In addition, the present invention can use various converted differential values having insensitive characteristics of water sensing so as to distinguish the sensing of the presence of water, that is, the sensing of the water region as a touch and the sensing by a general touch. The accumulation value used in the embodiment of the present invention illustrates an example of the converted differential value.

1, an embodiment according to the present invention may be implemented on a differential touch sensing system.

The differential touch sensing system may include a PWM control unit 10, a driving circuit 12, a touch panel 14, a sensing circuit 16 and an image buffer 18.

The PWM control unit 10 provides a driving pulse for periodic sensing.

The driving circuit 12 provides a driving signal synchronized with the driving pulse to the touch panel 14. At this time, the driving signal may be provided to the touch panel 14 in a differential manner.

The touch panel 14 includes a plurality of driving lines (not shown) and a plurality of sensing lines (not shown). The plurality of driving lines and the plurality of sensing lines may be variously formed according to a manufacturer's intention, and may be generally formed to cross each other or to be arranged side by side to share the electrostatic capacity of spaced apart spaces.

Therefore, a driving signal is applied to the driving line, and a sensing signal is output from the sensing line. In addition, when a change in capacitance occurs by a touch, the sensing signal outputs a sensing signal reflecting the change in capacitance.

That is, the touch panel 14 is configured to output the sensing signal corresponding to the periodically applied driving signal in a differential manner.

The sensing circuit 16 transmits a sensing signal applied differentially from the touch panel 14 to the image buffer 18. Here, the sensing circuit 16 may be configured to perform functions such as amplification of the sensing signal or noise filtering.

The image buffer 18 may be configured to include a frame-by-frame storage capable of accommodating a full frame of the touch panel 14, and convert and store analog signals transmitted from the sensing circuit 16 to have digital values. It can be configured to output. That is, the image buffer 18 outputs a sensing signal as a digital signal.

Hereinafter, the coordinate selection circuit 20 configured as an embodiment according to the present invention to be described receives a sensing signal that is a digital signal output from the image buffer 18, and the sensing signal described by the coordinate selection circuit 20 is low. It is expressed as sensing data in the form of data (Raw Data). The raw data refers to data having a differential value to which digital values are mapped by being divided according to positions of a plurality of scan lines with respect to a frame area of the touch panel 14.

The coordinate selection circuit 20 includes a first detection unit 22, a second detection unit 24, a water detection unit 26, and a coordinate selection unit 28.

The first detection unit 22 includes a partial region accumulation unit 30, a labeling unit 32, and a coordinate calculation unit 34, and detects accumulation values, a first labeling value, and a first coordinate first. It has a configuration to output as information.

The partial region accumulation unit 30 in the first detection unit 22 receives the sensing data from the image buffer 18 and converts the differential values of the portion in which the change is sensed among the sensing data into accumulation values (Partial Region) Accumulation).

Here, the partial region accumulation unit 30 may calculate accumulation values by sequentially integrating differential values corresponding to one sensing line of the touch panel 14 in one direction.

The labeling unit 32 provides a first labeling value counting the number of positions equal to or greater than a first preset threshold value for the accumulated values provided by the partial region accumulation unit 30.

The coordinate calculating unit 34 receives the first labeling value from the labeling unit 32 and calculates and provides the first coordinate corresponding to each location counting the first labeling value.

Meanwhile, the second detection unit 24 is configured to output second detection information according to the differential values, and includes a labeling unit 40 and a coordinate calculation unit 42 for this purpose.

The labeling unit 40 is configured to provide a second labeling value counting the number of positions equal to or greater than a preset second threshold value for differential values.

The coordinate calculation unit 42 has a configuration in which the second coordinates corresponding to each position counting the second labeling value are calculated and provided.

On the other hand, the water detector 26 has a configuration that outputs a selection signal as a result of detecting the presence of water by comparing the first detection information and the second detection information.

In addition, the coordinate selection unit 28 receives the first coordinates of the coordinate calculation unit 34 of the first detection unit 22 and the second coordinates of the coordinate calculation unit 42 of the second detection unit 22, and detects water. One of the first coordinates and the second coordinates is selected by the selection signal provided from the unit 26 and output as coordinates corresponding to the touch.

That is, the coordinate selector 28 selects and outputs one of the first coordinates corresponding to the accumulated values and the second coordinates corresponding to the differential values as coordinates.

As a result, the coordinate selection unit 28 selects the first coordinates by the selection signal of the water detection unit 26 corresponding to the case where water is present and the water detection unit 26 corresponding to the case where water is not present. The second coordinates are selected and output according to the selection signal of.

The embodiment according to the present invention configured as described above selects the first coordinate or the second coordinate in response to the touch. More specifically, when no water is present on the touch panel 14, the second coordinates generated as differential values of sensing data may be selected. Alternatively, when there is water on the touch panel 14 and senses it, the first coordinates generated as values having differential characteristics of the sensing data in the water may be selected.

The above-mentioned accumulation value can be exemplified for a value having a property insensitive to water.

A process in which differential values corresponding to the touch are converted into accumulated values will be described with reference to FIG. 2.

First, the differential values corresponding to the touch having the pattern as shown in FIG. 2 (a) exist after a positive value above a certain level based on the scanning direction (eg, from left to right) of the sensing line, and then a negative value below a certain level It has a distribution with values.

Differential values having the above-described distribution are converted to have a pattern as shown in FIG. 2 (b) when they are accumulated along the scan direction.

More specifically, the differential values in FIG. 2 (a) have a distribution having values of '25', '147', '188', '-268', and '-146'. When the differential values of FIG. 2 (a) are accumulated along the scan direction, the accumulation values are distributed with values of '25', '172', '260', '92', and '-54' as shown in FIG. 2 (b). Have

The accumulated value '172' is derived as the sum of '25' and '147' of the differential values, and the accumulated value '360' is derived as the sum of the previous accumulated value '172' and the differential value '188', and the accumulated value '92 'Is derived as the sum of the previous accumulated value' 360 'and the differential value' -268 ', and the accumulated value' -54 'is derived as the sum of the previous accumulated value' 92 'and the differential value' -146 '.

The first threshold value of FIG. 2 (b) is used to obtain the first labeling value from the labeling unit 32, and the second threshold value of FIG. 2 (a) is the second labeling value of the labeling unit 40. It is used to obtain. Here, the first threshold value and the second threshold value may be set at the same level or may be set at different levels in consideration of characteristics of the differential value and the accumulated value.

On the other hand, differential values due to normal touch such as a finger touch and differential values due to water may be contrasted as shown in FIG. 3. Differential values due to water have a wider spreading characteristic with lower capacitance change characteristics than those caused by a finger. In the waveform of FIG. 3, the upper part is an area in which positive values are distributed and the lower part is an area in which negative values are distributed based on the center. The difference in the capacitance change between water and the finger is caused by the difference in intrinsic resistance characteristics between water and the finger.

However, as shown in FIG. 3, it is difficult to distinguish between a change in the electrostatic capacity due to water and a change in the correcting capacity due to the finger, i.e., a touch caused by water and a touch caused by finger, with differential values having little difference.

Therefore, in order to distinguish and sense the finger touch when water is present, it is necessary to convert the differential values in FIG. 3 into values insensitive to water characteristics.

To this end, the differential values of FIG. 3 according to the touch that recognizes the presence of water and the touch by the finger may be converted into accumulated values of the waveform shown in FIG. 4. That is, the differential values in FIG. 3 are converted into the accumulation values in FIG. 4 by the same conversion as in FIG. 2.

Referring to FIG. 4, the waveform according to the finger touch has a characteristic having a strong distribution as the positive value increases, and the waveform due to the touch of water has a characteristic having a strong distribution as the distribution for the positive value is weak while the negative value increases.

3 and 4, differential values and accumulation values recognizing a finger touch may be illustrated as a raw data map as shown in FIG. 5, and differential values and accumulation values recognizing the presence of water are shown in FIG. It can be illustrated as a raw data map.

The hatching area of FIGS. 5 and 6 is for displaying a touch-recognized area.

According to an embodiment of the present invention, when water is present, the first coordinates obtained as accumulated values are selected as finger touched coordinates, and when water is not present, the second coordinates obtained as differential values are selected as finger touched coordinates. do.

The second coordinate obtained by the differential values is more accurate than the first coordinate obtained by the accumulation values. However, when water is present, it is difficult to obtain a second coordinate corresponding to a finger touch by distinguishing it from water by differential values. Therefore, when water is present, the present invention obtains a first coordinate corresponding to a finger touch as an accumulation value having a desensitizing property for water. That is, the position of the general touch when water is present on the touch panel 14 may be determined by using the first coordinates obtained by the accumulated values even if the accuracy is somewhat lower.

FIG. 7 is a view for explaining the operation of the embodiment of FIG. 1 when water is not present, and FIG. 8 is a view for explaining the operation of the embodiment of FIG. 1 when water is present.

A case where water is not recognized on the touch panel 14 will be described with reference to FIGS. 1 and 7.

The sensing data transmitted from the image buffer 18 has differential values as shown in FIG. 5 (a) and a partial region accumulation unit 30 of the first detection unit 22 and a labeling unit 40 of the second detection unit 24 Is entered as

First, the partial region accumulation unit 30 performs a calculation that converts differential values of a portion where a change is sensed in sensing data to accumulation values.

Here, the portion where the change is detected may be defined by detecting that the differential value of the sensing data changes beyond a preset reference width.

The labeling unit 32 counts positions at which accumulation values provided by the partial region accumulation unit 30 have a positive value higher than the first threshold value illustrated in FIG. 2B. Touch is made over a plurality of areas. Therefore, assuming a case where the first threshold value is set to '10', three first labeling values for each scan line may be obtained for the portion where the change illustrated in FIG. 5B is sensed.

In parallel with this, the labeling unit 40 counts positions where the differential values have a positive value higher than the second threshold value shown in FIG. 2 (a). Assuming the case where the second threshold value is set to '10', in the case where the change illustrated in FIG. 5A is detected, two second labeling values may be obtained for each scan line.

The coordinate calculator 34 calculates and provides the first coordinates X11 and Y12 corresponding to each position where the labeling value is counted by the labeling unit 32, and the coordinate calculator 42 labels the labeling unit 40 The corresponding second coordinates (X21, Y21) are calculated and provided for each position where the value is counted.

In this case, in the case of multi-touch, a plurality of first coordinates X11 and Y12 and second coordinates X21 and Y21 may be provided.

By the above-described process, differential values, accumulation values, first and second labeling values, and first and second coordinates of a portion where a change is detected may be obtained.

The water detector 26 is provided with first detection information including an accumulated value, a first labeling value, and first coordinates and second detection information including a differential value, a second labeling value, and second coordinates.

The water detector 26 may determine the presence of water by comparing the first detection information and the second detection information, and output a selection signal for selecting the first coordinate or the second coordinate according to the presence or absence of water.

First, when the first result comparing the first and second labeling values and the second result comparing the first and second coordinates are all within the allowable range, the water detector 26 detects that water does not exist. The corresponding selection signal is output.

In the case of FIG. 7, there is one difference between the first and second labeling values of three and two. However, assuming that the allowable range is set to allow one difference, the water detector 26 determines the first result as a match.

In addition, the water detection unit 26 has a difference in which the first coordinates X11 and Y12 and the second coordinates X21 and Y21 correspond to the difference between the first and second labeling values. However, assuming that the allowable range is set to allow one error as described above, the water detection unit 26 determines the second result as a match.

As shown in FIG. 7, when it is determined that there is no water in the touch panel 14 because both the first result and the second result are identical, the water detector 26 outputs a selection signal corresponding thereto.

On the other hand, if the result of comparing the first and second labeling values matches within the allowable range and the signal distribution state of the differential values corresponding to the first coordinates is normal, the water detector 26 determines that there is no water. The corresponding selection signal is output.

More specifically, in the case of FIG. 7, the water detection unit 26 determines that the first and second labeling values meet and satisfy the allowable range as described above.

Then, the water detection unit 26 has a positive value above a certain level in the differential values within a predetermined range before the first coordinate based on the scan direction of the sensing line and a predetermined level below the differential values in a predetermined range after the first coordinate When the negative value of exists, the signal distribution state is determined to be normal.

Of course, according to the manufacturer's intention, the water detector 26 has a positive value above a certain level in the differential values within a predetermined range before the first coordinate based on the scan direction of the sensing line and a differential value within a predetermined range after the first coordinate It may be configured to judge the signal distribution state as any one of those having a negative value below a certain level in the field.

When the first and second labeling values match and the signal distribution state of the differential values corresponding to the first coordinates is normal as described above, the water detector 26 determines that water is not present and outputs a selection signal corresponding thereto. do.

In addition, if the result of comparing the first and second labeling values matches within the allowable range and the signal distribution state of the accumulated values corresponding to the second coordinates is normal, the water detector 26 determines that there is no water. And outputs a selection signal corresponding thereto.

More specifically, in the case of FIG. 7, the water detection unit 26 determines that the first and second labeling values satisfy and satisfy the allowable range as described above.

Then, the water detection unit 26 determines that the signal distribution state is normal when a positive value of a predetermined level or more is present in accumulated values within a predetermined range after the second coordinate based on the scan direction of the sensing line.

Therefore, if the first and second labeling values match and the signal distribution state of the accumulation values corresponding to the second coordinates is normal, the water detection unit 26 determines that water does not exist and outputs a selection signal corresponding thereto. .

In contrast, with reference to FIG. 8, the operation of the water detector 26 when water is present on the touch panel 14 will be described.

In this case, the sensing data includes not only the differential values recognizing the finger touch, but also differential values recognizing the water region existing on the touch panel 14. That is, the sensing data includes differential values corresponding to the water region.

Therefore, in FIG. 8, the second coordinates based on the differential values input to the second detector 24, the second labeling values labeling the differential values generated by the second detector 24, and the second coordinates based on the second labeling values are water. The differential values that recognize the region are reflected.

The second labeling value generated from the above-mentioned differential values includes a labeling value that recognizes the water region on the touch panel 14, and the second coordinate includes a plurality of coordinates (Xn, Yn) of the water region.

On the other hand, the differential values output from the partial region accumulating unit 30 increase the size of a positive value corresponding to a finger touch, which is a normal touch, and the distribution is strengthened, and a degree corresponding to the water region is not detected as a first threshold value. The size of the positive value is reduced and the negative distribution is strengthened.

Therefore, the labeling unit 32 does not count the water area below the first threshold value and outputs the first labeling value counting only the accumulation value corresponding to a general touch such as a finger touch.

Accordingly, since the coordinate calculator 34 outputs the first coordinates based on the first labeling value, the first coordinates do not include coordinate values corresponding to the water region.

As a result, when water is present in the touch panel 14 as shown in FIG. 8, a difference out of the allowable range occurs between the first labeling value and the second labeling value, and a difference out of the allowable range between the first coordinate and the second coordinate. Occurs.

Therefore, the water detection unit 26 may display the touch panel 14 when one or more of the first result comparing the first and second labeling values and the second result comparing the first and second coordinates is outside an allowable range. It is determined that water is present and outputs a selection signal for selecting the first coordinate value output from the coordinate calculator 34.

As described above with reference to FIGS. 7 and 8, the water detection unit 26 outputs a selection signal for selecting the first coordinates of the coordinate calculation unit 34 when water is present on the touch panel 14 And outputs a selection signal for selecting the second coordinates of the coordinate calculator 42 when no water is present on the touch panel 14.

Accordingly, the coordinate selection unit 28 selects and outputs the first coordinate when water is present on the touch panel 14 and selects and outputs the second coordinate when water is not present on the touch panel 14. .

Therefore, according to an embodiment of the present invention, even if water is present, coordinates corresponding to a general touch such as a finger touch can be output without error.

That is, according to the present invention, the coordinates can be obtained by avoiding the water characteristic by the accumulated values, and if the water does not exist, the coordinates can be obtained by the differential values.

Therefore, the embodiment according to the present invention is resistant to noise due to water characteristics and can improve touch sensitivity and accuracy of sensing in response to the presence of water.

10: PWM control unit 12: driving circuit
14: touch panel 16: sensing circuit
18: image buffer 20: coordinate selection circuit
22: first detection unit 24: second detection unit
26: water detection unit 28: coordinate selection unit
30: partial area accumulation section 32, 40: labeling section
34, 42: coordinate calculator

Claims (20)

A first detection unit which converts differential values of a portion in which a change in the differential signal occurs to accumulation values and outputs first detection information according to the accumulation values;
A second detection unit which outputs second detection information according to the differential values;
A water detection unit that outputs a selection signal as a result of determining whether water is present by comparing the first detection information and the second detection information; And
It includes; a coordinate selector for selecting one of the first coordinates corresponding to the accumulated values and the second coordinates corresponding to the differential values by the selection signal and selecting and outputting the coordinates corresponding to the touch. The coordinate selection circuit of the differential touch sensing system.
According to claim 1,
The first detection unit is a coordinate selection circuit of the differential touch sensing system to obtain the accumulated values by sequentially integrating the differential values corresponding to one sensing line in one direction.
The method of claim 1, wherein the first detection unit,
A partial region accumulation unit for sequentially calculating the differential values corresponding to one sensing line in one direction to obtain the accumulation values;
A first labeling unit that provides a first labeling value counting the number of positions equal to or greater than a preset first threshold value for the accumulated values; And
And a first coordinate calculator configured to calculate and provide the first coordinates corresponding to each location counting the first labeling value.
The method of claim 1, wherein the second detection unit,
A second labeling unit providing a second labeling value counting the number of positions equal to or greater than a preset second threshold value for the differential values; And
And a second coordinate calculator configured to calculate and provide the second coordinates corresponding to each location counting the second labeling value.
According to claim 1,
The coordinate selector selects the first coordinate in response to the selection signal when the water is present, and selects the second coordinate in response to the selection signal when the water is not present, and outputs the coordinates corresponding to the touch. Coordinate selection circuit of differential touch sensing system.
According to claim 1, The water detector,
First receiving the first labeling value and the first coordinates as the first detection information, receiving the second labeling value and the second coordinates as the second detection information, and comparing the first and second labeling values If the result and the second result comparing the first and second coordinates are all within the allowable range, the selection signal corresponding to the case where the water does not exist is output, and one of the first result and the second result is output. When the abnormality is out of the allowable range, the selection signal corresponding to the presence of the water is output,
The first labeling value is a value obtained by counting the number of positions where the accumulated value is greater than or equal to a preset first threshold value, and the second labeling value is a value obtained by counting the number of positions where the differential value is greater than or equal to a preset second threshold value. Wherein, the first coordinate is a coordinate corresponding to each location counting the first labeling value, and the second coordinate is a coordinate selection circuit of a differential touch sensing system that is a coordinate corresponding to each location counting the second labeling value.
According to claim 1, The water detector,
The first labeling value and the first coordinates are received as the first detection information, the second labeling values and the differential values are received as the second detection information, and a result of comparing the first and second labeling values is allowed. When the signal distribution state of the differential values corresponding to the first coordinates within the range is normal, the selection signal corresponding to the case where the water does not exist is output, and the first and second labeling values are compared. If the result is outside the allowable range, the selection signal corresponding to the case where the water is present is output,
The first labeling value is a value obtained by counting the number of positions where the accumulated values are greater than or equal to a preset first threshold value, and the second labeling value is a value obtained by counting the number of positions where the differential values are greater than or equal to a preset second threshold value. Wherein, the first coordinate is a coordinate selection circuit of a differential touch sensing system that is a coordinate corresponding to each location counting the first labeling value.
The method of claim 7, wherein the water detector,
The differential values set the signal distribution state to normal when a positive value above a certain level exists before the first coordinate and a negative value below a certain level after the first coordinate based on the scan direction of the sensing line. Coordinate selection circuit of differential touch sensing system to judge.
According to claim 1, The water detector,
The first labeling value and the accumulated values are received as the first detection information, the second labeling value and the second coordinates are received as the second detection information, and a result of comparing the first and second labeling values is allowed. When the signal distribution state of the accumulation values corresponding to the second coordinates within the range is normal, the selection signal corresponding to the case where the water does not exist is output, and the first and second labeling values are compared. If the result is outside the allowable range, the selection signal corresponding to the case where the water is present is output,
The first labeling value is a value obtained by counting the number of positions where the accumulated values are greater than or equal to a preset first threshold value, and the second labeling value is a value obtained by counting the number of positions where the differential values are greater than or equal to a preset second threshold value. Wherein, the second coordinate is a coordinate selection circuit of the differential touch sensing system that is a coordinate corresponding to each location counting the second labeling value.
The method of claim 9, wherein the water detector,
The accumulated values are coordinate selection circuits of the differential touch sensing system that determines the signal distribution state as normal when a positive value of a predetermined level or more is present after the second coordinate based on the scan direction of the sensing line.
According to claim 1,
The differential values are differential touch, which is raw data having a differential value counted for each position of a plurality of scan lines corresponding to a frame of the touch panel, after the sensing signal output from the touch panel is stored in an image buffer. Coordinate selection circuit of sensing system.
Converting differential values of a portion where a change in the differential signal is detected to accumulated values;
Providing a first labeling value counting the number of positions above a preset first threshold value for the accumulated values;
Providing a second labeling value counting the number of positions equal to or greater than a second preset threshold value for the differential values;
Calculating and providing first coordinates corresponding to each location counting the first labeling value;
Calculating and providing a second coordinate corresponding to each location counting the second labeling value;
Outputting a selection signal by determining the presence of water using at least two of the accumulated value, the differential value, the first labeling value, the second labeling value, the first coordinates, and the second coordinates; And
And selecting and outputting one of the first coordinates and the second coordinates as coordinates corresponding to a touch according to the selection signal; and a method for selecting coordinates of a differential touch sensing system.
The method of claim 12,
When the first result comparing the first and second labeling values and the second result comparing the first and second coordinates all match within an allowable range, the selection signal is output in response to the absence of water, A coordinate selection method of the differential touch sensing system that outputs in response to the presence of water when at least one of the first result and the second result is outside an allowable range.
The method of claim 12,
The selection signal is output in response to the absence of water if the result of comparing the first and second labeling values coincides within an allowable range and the signal distribution state of the differential values corresponding to the first coordinate is normal. And, when the result of comparing the first and second labeling values out of the allowable range, the coordinate selection method of the differential touch sensing system to output in response to the presence of water.
The method of claim 12,
The selection signal is output in response to the absence of water if the result of comparing the first and second labeling values coincides within an allowable range and the signal distribution state of the accumulation values corresponding to the second coordinate is normal. And, when the result of comparing the first and second labeling values is outside the allowable range, the coordinate selection method of the differential touch sensing system that outputs in response to the presence of water.
The method of claim 12,
Coordinate selection of the differential touch sensing system selecting the first coordinates in response to the selection signal corresponding to the presence of water and the second coordinates in response to the selection signal corresponding to the absence of water. Way.
A first detection unit which converts differential values of a portion in which a change in the differential signal occurs to accumulation values and outputs first detection information according to the accumulation values;
A second detection unit which outputs second detection information according to the differential values;
A detection unit comparing the first detection information and the second detection information to determine whether a capacitive substance is present and to output a selection signal corresponding to the determination result; And
Coordinates selecting the first coordinates corresponding to the accumulation values when the capacitive substance is present and the second coordinates corresponding to the differential values when the capacitive substance is not present by the selection signal. Coordinates selection circuit of the differential touch sensing system, characterized in that it comprises a.
The method of claim 17,
The first detection unit provides the first coordinates, and the second detection unit provides the second coordinates Coordinate selection circuit of the differential touch sensing system.
Converting differential values of a portion where a change in the differential signal is detected to accumulated values;
Providing a labeling value counting the number of positions above a preset threshold value for the accumulated values; And
Includes; calculating and providing the corresponding coordinates for each location counting the labeling value,
A coordinate selection method of a differential touch system that defines a region in which the accumulation value of the negative value is distributed over a certain range as a water region and provides the coordinates for the water region.
The method of claim 19,
The water region is a coordinate selection method of a differential touch system that is defined by determining the distribution of the accumulated value using the labeling value.

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