KR102024781B1 - Electronic device having a touch sensor and driving method thereof - Google Patents

Abstract

The present invention relates to a touch screen including touch sensors defined by Tx lines and Rx lines; A touch sensing circuit which supplies a driving signal to the Tx lines and senses a voltage change of the touch sensors through the Rx lines to output touch raw data; And a touch sensor that defines touch raw data for each region, changes the filtering intensity for each region, and calculates a coordinate for a touch input position.

Description

ELECTRONIC DEVICE HAVING A TOUCH SENSOR AND DRIVING METHOD THEREOF

The present invention relates to an electronic device having a touch sensor and a driving method thereof.

BACKGROUND In various electronic devices such as home appliances and portable information devices, user input means have been replaced by touch sensors in button-type switches according to the trend of light weight and slimness. Accordingly, recently released electronic devices such as display devices have a touch sensor (or touch screen).

The capacitive type touch sensor, which is one of the touch sensors, may detect the presence and coordinate of a touch by sensing a change in mutual capacitance when a human finger or a conductive material contacts or approaches. In this case, in order to measure a change in mutual capacitance and determine information on a touch, each sensor node of the touch screen panel is set, a driving signal is output, a change in mutual capacitance of the touch screen panel is sensed, and the data is binarized. The process goes on.

Meanwhile, a touch sensor such as a capacitive type uses various filters to remove noise generated by various causes and to improve performance and uniformity of touch sensing. However, in the related art, secondary problems are caused by using the same and excessive filtering not only for the effective touch area but also for the invalid touch area as well as for the purpose of improving the performance and the uniformity of the touch sensing.

The present invention for solving the above problems of the background art and an electronic device having a touch sensor that can reduce the throughput (or degradation) of the data while minimizing the distortion of the signal appearing in the touch boundary area and increasing linearity It is to provide a driving method.

The present invention provides a touch screen including touch sensors defined by Tx lines and Rx lines. A touch sensing circuit which supplies a driving signal to the Tx lines and senses a voltage change of the touch sensors through the Rx lines to output touch raw data; And a touch sensor that defines touch raw data for each region, changes the filtering intensity for each region, and calculates a coordinate for a touch input position.

The touch coordinate detection unit analyzes the touch raw data to filter an effective touch area in which the touch raw data exists, an invalid touch area in which the touch raw data does not exist, and a boundary area existing between the valid touch area and the invalid touch area. An area defining unit, a filtering unit for varying the filtering intensity for the touch raw data located in the effective touch area, the invalid touch area, and the boundary area, and an identification number to the touch raw data filtered for each area, and It may include a coordinate calculation unit for calculating the coordinates for the.

The filtering unit may increase the filtering intensity of the touch raw data positioned in the boundary area than the ineffective touch area and the effective touch area.

The filtering unit may not perform filtering on the touch raw data located in the invalid touch region.

If the number of touch raw data located in the effective touch area is larger than the number of touch raw data in the invalid touch area based on the boundary area, the filtering unit may filter the touch raw data of the effective touch area adjacent to the boundary area with a high weight. Can be.

If the number of touch raw data of the invalid touch area and the number of touch raw data located in the effective touch area are the same with respect to the boundary area, the filtering unit has a high weight on the touch raw data of the valid touch area and the invalid touch area adjacent to the border area. You can filter by.

If the number of touch raw data of the invalid touch area is greater than the number of touch raw data located in the effective touch area based on the boundary area, the filtering unit has a high weight on the touch raw data of the effective touch area and the invalid touch area adjacent to the border area. You can filter by.

In another aspect, the present invention provides a method of providing touch raw data by supplying a driving signal to Tx lines of a touch screen including touch sensors and sensing a voltage change of the touch sensors through the Rx lines; By analyzing the touch raw data, an effective touch area in which the touch raw data exists, an invalid touch area in which the touch raw data does not exist, and a boundary area existing between the valid touch area and the invalid touch area are defined, Determining and varying filtering strengths for touch raw data located in the effective touch area and the border area; And assigning an identification number to the touch raw data filtered for each region and calculating coordinates for the touch input position.

Determining and varying the filtering intensity may result in a higher filtering intensity for touch raw data located in the boundary region than in the invalid touch region and the effective touch region.

Determining and varying the filtering strength may not perform filtering on the touch raw data located in the invalid touch region.

According to the present invention, a touch sensor capable of reducing data throughput (or deterioration) while minimizing signal distortion and increasing linearity by applying different filtering to locations where signal distortion in the touch area is likely to occur and difficult locations is different. It is effective to provide an electronic device having a and a driving method thereof.

1 illustrates an electronic device having a touch sensor according to an embodiment of the present invention.
FIG. 2 is an equivalent circuit diagram of the touch screen shown in FIG. 1.
3 to 5 illustrate various combinations of a liquid crystal display panel and a touch screen.
6 is a view for explaining a problem caused by the filtering method of the comparative example.
7 is a diagram illustrating a filtering concept of an adaptive smoothing filter according to an embodiment of the present invention.
8 illustrates an example of a touch sensor located at a boundary area.
9 is a view for explaining a filtering condition for each region.
10 is a schematic flowchart of a method of driving an electronic device having a touch sensor according to an embodiment of the present invention.
11 is a detailed flowchart for determining filtering strength by region.

Hereinafter, with reference to the accompanying drawings, the specific content for the practice of the present invention will be described.

1 is a diagram illustrating an electronic device having a touch sensor according to an embodiment of the present invention, FIG. 2 is an equivalent circuit diagram of the touch screen shown in FIG. 1, and FIGS. 3 to 5 are various views of a liquid crystal display panel and a touch screen. 6 are diagrams illustrating a combined form, and FIG. 6 is a diagram for describing a problem caused by the filtering method of the comparative example.

An electronic device having a touch sensor of the present invention is implemented as a television, a set top box, a navigation, a video player, a Blu-ray player, a personal computer (PC), a home theater and a mobile phone. An electronic device having a touch sensor of the present invention is implemented based on a display panel. The display panel may be a flat panel display panel such as a liquid crystal display panel, an organic light emitting display panel, an electrophoretic display panel, a plasma display panel, but is not limited thereto. However, in the following description, a liquid crystal display panel is described as an example for convenience of description.

An electronic device having a touch sensor includes a host system 50, a timing controller 20, a data driving circuit 12, a scan driving circuit 14, a liquid crystal display panel DIS, a touch screen TSP, and a touch screen driving circuit. (30, 40).

The host system 50 includes a system on chip (SoC) incorporating a scaler, which converts digital video data RGB of an input image into a format suitable for displaying on a liquid crystal display panel DIS. The host system 50 transmits timing signals Vsync, Hsync, DE, and MCLK together with the digital video data to the timing controller 20. The host system 50 executes an application program associated with the coordinate information XY of the touch input position input from the touch coordinate detector 40.

The timing controller 20 receives timing signals such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a data enable signal Data Enable, DE, and a main clock MCLK from the host system 50. Based on this, the data driving circuit 12 and the scan driving circuit 14 are controlled.

The timing controller 20 is a scan driving circuit based on scan timing control signals such as a gate start pulse (GSP), a gate shift clock, and a gate output enable signal (GOE). (14). The timing controller 20 is a data driving circuit based on data timing control signals such as a source sampling clock (SSC), a polarity control signal (Polarity, POL), and a source output enable signal (SOE). To control (12).

The data driving circuit 12 converts the digital video data RGB input from the timing controller 20 into an analog positive / negative gamma compensation voltage to generate a data voltage. The data driving circuit 12 supplies a data voltage through the data lines D1 to Dm.

The scan driving circuit 14 sequentially generates gate pulses (or scan pulses) synchronized with the data voltages. The scan driving circuit 14 supplies a gate pulse through the gate lines G1 to Gn.

The liquid crystal display panel DIS displays an image based on the gate pulse supplied from the scan driving circuit 14 and the data voltage supplied from the data driving circuit 12. The liquid crystal display panel DIS includes a liquid crystal layer formed between two substrates GLS1 and GLS2. The liquid crystal display panel DIS may be implemented in any known liquid crystal mode, such as a twisted nematic (TN) mode, a vertical alignment (VA) mode, an in plane switching (IPS) mode, and a fringe field switching (FFS) mode.

The subpixels of the liquid crystal display panel DIS are defined by data lines D1 to Dm, where m is a positive integer, and gate lines G1 to Gn, where n is a positive integer. One subpixel is a thin film transistor (TFT) formed at intersections of the data line and the gate line, a pixel electrode for charging a data voltage, and a storage capacitor connected to the pixel electrode to maintain the voltage of the liquid crystal cell. ), And the like.

A black matrix, a color filter, and the like are formed on the upper substrate GLS1 of the liquid crystal display panel DIS. The lower substrate GLS2 of the liquid crystal display panel DIS may be implemented in a color filter on TFT (COT) structure. In this case, the black matrix and the color filter may be formed on the lower substrate GLS2 of the liquid crystal display panel DIS. The common electrode supplied with the common voltage may be formed on the upper substrate GLS1 or the lower substrate GLS2 of the liquid crystal display panel DIS. Polarizing plates POL1 and POL2 are attached to the upper substrate GLS1 and the lower substrate GLS2 of the liquid crystal display panel DIS, and an alignment layer for setting the pretilt angle of the liquid crystal is formed on the inner surface of the liquid crystal display panel DIS.

A column spacer for maintaining a cell gap of the liquid crystal cell is formed between the upper substrate GLS1 and the lower substrate GLS2 of the liquid crystal display panel DIS. The backlight unit is disposed under the rear surface of the lower polarizer POL2 of the liquid crystal display panel DIS. The backlight unit is implemented in an edge type or a direct type to provide light to the liquid crystal display panel DIS.

The touch screen TSP includes Tx lines (Tx1 to Txj, j is a positive integer smaller than n), and Rx lines (Rx1 to Rxi and i are positive amounts smaller than m) intersecting the Tx lines (Tx1 to Txj). Integer), and i × j touch sensors Cts formed at intersections of the Tx lines Tx1 to Txj and the Rx lines Rx1 to Rxi. The touch sensors Cts each include a capacitance when viewed in an equivalent circuit.

The capacitance can be classified into a self capacitance or a mutual capacitance. The self capacitance is formed along a single layer of conductor wiring formed in one direction. Mutual capacitance is formed between two orthogonal conductor wires. The embodiment illustrates a mutual capacitive touch screen, but the present invention is not limited thereto.

The touch screen TSP may be implemented to be positioned on the upper polarizer POL1 of the liquid crystal display panel DIS as shown in FIG. 3. The touch screen TSP may be implemented to be positioned between the upper polarizing plate POL1 and the upper substrate GLS1 of the liquid crystal display panel DIS as shown in FIG. 4. As illustrated in FIG. 5, the touch screen TSP may be implemented in such a manner that the pixel electrode PIX and the touch sensor Cts of the lower substrate GLS2 are located together to be embedded in the liquid crystal display panel DIS.

The touch screen driving circuits 30 and 40 supply a driving signal to the touch sensors Cts to sense a voltage change of the touch sensor before and after the touch input, and compare the voltage change with a predetermined touch threshold value to determine the touch input position. Detect. The touch screen driving circuits 30 and 40 calculate coordinates of the touch input position.

The touch sensing circuit 30 includes a Tx driving circuit 32, an Rx driving circuit 34, a Tx / Rx controller 38, and the like. The touch sensing circuit 30 applies a driving signal to the touch sensors Cts through the Tx lines Tx1 to Txj using the Tx driving circuit 32, and Rx lines Rx1 to synchronously with the driving signal. The touch raw data is output by sensing the voltages of the touch sensors Cts through Rxi and Rx driving circuit 34. The driving signal may be formed in various forms such as a pulse, a sinusoidal wave, and a triangular wave. The touch sensing circuit 30 may be integrated into one read-out integrated circuit (ROIC).

The Tx driving circuit 32 selects a Tx channel for outputting a driving signal in response to the Tx setup signal from the Tx / Rx controller 38 and applies the driving signal to the Tx lines Tx1 to Txj connected to the selected Tx channel. Is authorized. The Tx lines Tx1 to Txj are charged during the high potential period of the driving signal to supply charge to the touch sensors Cts. The driving signal is connected to the Tx lines Tx1 to Txj so that the voltages of the touch sensors Cts are accumulated on the capacitor of the integrator built in the Rx driving circuit 34 through the Rx lines Rx1 to Rxi. N (N is a positive integer above) can be supplied continuously to each.

The Rx driving circuit 34 selects Rx lines to receive the voltage of the touch sensor in response to the Rx setup signal from the Tx / Rx controller 38, and touches the touch sensor Cts through the selected Rx lines in synchronization with the driving signal. Receive and sample the output voltage of. The Rx driving circuit 34 accumulates the sampled voltage in the integrator capacitor, converts the voltage of the capacitor into digital data using an analog-to-digital converter (hereinafter referred to as "ADC"), and Digital data is output as touch raw data.

The Tx / Rx controller 38 controls the Tx channel and Rx channel settings in response to the Tx setup signal and the Rx setup signal from the touch coordinate detector 40 and synchronizes the Tx driver circuit 32 and the Rx driver circuit 34. Let's do it.

The touch coordinate detector 40 includes a filtering area definer 42, a filter 44, a coordinate calculator 46, and the like. The touch coordinate detector 40 supplies the Tx setup signal and the Rx setup signal to the Tx / Rx controller 38 and supplies the ADC clock signal for operating the ADC of the Rx driver circuit 34 to the Rx driver circuit 34. . The touch coordinate detector 40 may be implemented as a micro controller unit (MCU).

The filtering area defining unit 42 analyzes the touch raw data to analyze the effective touch area in which the touch raw data exists, the invalid touch area in which the touch raw data does not exist, and the boundary area existing between the valid touch area and the invalid touch area. Define each one. The filtering unit 44 varies the filtering intensity with respect to the touch raw data defined for each region by the filtering region defining unit 42. In the drawing, the filtering region defining unit 42 and the filtering unit 44 are divided for clarity, but they may be integrated into one filtering unit.

The coordinate calculator 46 calculates coordinates of the touch raw data from which components such as noise are filtered. The coordinate calculator 46 compares the touch raw data received through the filtering area defining unit 42 and the filtering unit 44 with a preset touch threshold value. The coordinate calculator 46 determines only the touch threshold value or more of the touch raw data as the touch data obtained from the touch sensors Cts.

The coordinate calculator 46 assigns an identification number to each of the touch raw data equal to or greater than the touch threshold value, calculates coordinates for each of the touch input positions, and transmits each identification number and coordinate information XY to the host system 50. To send.

Meanwhile, in the electronic device having the touch sensor of the comparative example, when the touch area TA is generated on the touch screen TSP as shown in FIG. 6, the effective touch area VTA, the invalid touch area ITA, and the boundary area BTA are used. The same filtering was performed on all the touch raw data present in the. For example, the electronic device having the touch sensor of the comparative example performs filtering with a filtering strength of "2" without distinguishing between the effective touch area VTA, the invalid touch area ITA, and the boundary area BTA.

However, when the smoothing filter, which is one of the filtering methods, is performed in the same manner as in the comparative example, the blockage of the line due to jitter noise generated when the line is drawn is performed. Distortion of the same signal occurs. Therefore, the same method as the comparative example receives all the same filtering intensity values "2" regardless of the area, thereby affecting the performance of other touch algorithms as well as deterioration due to an increase in throughput of data when performing the smoothing filter.

The embodiment of the present invention provides a filtering region defining unit 42 constituting an adaptive smoothing filter capable of reducing data throughput (or degradation) while increasing linearity by varying the region-specific filtering strength. The filter 44 is proposed, which will be described below.

Hereinafter, the filtering region defining unit 42 and the filtering unit 44 constituting the adaptive smoothing filter will be described with reference to FIGS. 1 and 7 to 9.

FIG. 7 is a diagram illustrating a filtering concept of an adaptive smoothing filter according to an exemplary embodiment of the present invention, FIG. 8 is a diagram illustrating an example of a touch sensor located in a boundary region, and FIG. 9 illustrates filtering conditions for each region. It is a figure for demonstrating.

As shown in FIG. 7, when the touch area TA is generated in the touch screen TSP, the filtering area defining unit 42 may apply touch raw data existing only inside the touch area TA to the effective touch area VTA. Defined by the data. The filtering area defining unit 42 defines touch raw data existing only outside the touch area TA as data of the invalid touch area ITA. The filtering area defining unit 42 defines the touch raw data existing between the inside and the outside of the touch area TA as the data of the boundary area BTA.

The filtering area defining unit 42 analyzes the clustering of the touch raw data and defines an area having the clustering of the touch raw data as the effective touch area VTA. In addition, the filtering area defining unit 42 analyzes the clustering of the touch raw data and defines an area having no clustering of the touch raw data as an invalid touch area ITA. In addition, the filtering area defining unit 42 analyzes the clustering of the touch raw data and defines a region having a lower clustering of the touch raw data than the effective touch area and higher than the invalid touch area as the boundary area BTA. The filtering area defining unit 42 defines the effective touch area VTA and the invalid touch area ITA, and defines an area therebetween as a boundary area BTA, and the like. Since the effective touch area ITA and the border area BTA can be defined, the present invention is not limited to the above description.

As illustrated in FIG. 8, touch raw data q0 to q2 of the effective touch area VTA are obtained from a touch sensor positioned inside the touch area TA based on the boundary area BTA. Touch raw data p0 to p2 of the ineffective touch area ITA are obtained from a touch sensor located outside the touch area TA with respect to the boundary area BTA. The touch raw data q0, p0 or p0 and p0 of the boundary area BTA are obtained from a touch sensor adjacent to the inside or outside of the touch area TA.

On the other hand, when the touch area TA is generated on the touch screen TSP, the frequency, amount, and size of jitter noise occur in the order of boundary area BTA> effective touch area VTA> invalid touch area ITA. appear. That is, the boundary area BTA corresponds to an area where signal distortion is likely to occur.

Since the jitter noise is different for each region as described above, the filtering unit 44 varies the filtering intensity of the touch raw data for each region defined by the filtering region defining unit 42. The filtering unit 44 makes the filtering strength of the boundary area BTA higher than the invalid touch area ITA and the effective touch area VTA. For example, as illustrated in FIG. 7, the filtering unit 44 sets the filtering strength value for the boundary area BTA to "2" and the filtering strength value for the effective touch area VTA to "1". The filtering is performed after setting the filtering strength value for the invalid touch area ITA to "0". Meanwhile, in the case of the invalid touch area ITA, the filtering strength value is set to "0", which means that the filtering is not performed. On the other hand, the touch raw data located in the region where the filtering is not performed may be deleted or ignored when calculating the coordinates later for the purpose of increasing and improving linearity, but is not limited thereto.

When the touch area TA is generated, if the filtering intensity value is changed for each region as in the embodiment of the present invention, the same throughput intensity value is set for all regions, and data throughput (or degradation phenomenon) is more than when performing filtering. ) Can be reduced.

On the other hand, in the boundary area BTA, there is touch raw data overlapping the effective touch area VTA and the invalid touch area ITA. The filtering unit 44 may analyze the number of touch raw data for each location and perform filtering by varying the weight depending on whether or not the area exists closer to the region, which will be described in detail with reference to FIG. 9. .

Examples of touch raw data overlapping the boundary area BTA include (a) to (c). Since (a) to (c) correspond to touch raw data existing in the boundary area BTA, the filtering strength value TAS is set to "2". However, in (a) to (c), the objects of the touch raw data to be weighted are classified as follows.

(a) shows a filter tap with a larger number of touch raw data located in the effective touch area VTA than the ineffective touch area ITA on the basis of the boundary area BTA. (p0 <p1 to p3) The filtering unit 44 filters the touch raw data p1 to p3 of the effective touch area VTA adjacent to the boundary area BTA with a high weight.

(b) shows filter taps in which the number of touch raw data of the invalid touch area ITA and the number of touch raw data located in the effective touch area VTA are equal to each other based on the boundary area BTA. (p0 to p1) = p2 to p3) In this case, the filtering unit 44 may apply to the touch raw data p1, p2 or p1 to p2 of the effective touch area VTA and the invalid touch area ITA adjacent to the boundary area BTA. Filter with high weights.

(c) shows filter taps in which the number of touch raw data of the invalid touch area ITA is greater than the number of touch raw data located in the effective touch area VTA, based on the boundary area BTA. (p0 to p2) > p3) In this case, the filtering unit 44 has a high weight on the touch raw data p2, p3 or p2 to p3 of the effective touch area VTA and the invalid touch area ITA adjacent to the boundary area BTA. Filter by

Meanwhile, there is touch raw data located in the effective touch area VTA or the invalid touch area ITA with respect to the boundary area BTA. The filtering unit 44 may move the positions of the filter tabs to filter them, which will be described in detail with reference to FIG. 9.

Examples of the touch raw data located in the ineffective touch area ITA or the effective touch area VTA and in contact with the boundary area BTA may include (d) and (e). Since (d) and (e) exist separately in the invalid touch area ITA and the effective touch area VTA, the filtering strength value TAS is set to "1". Unlike (e), (d) may be regarded as being included in the touch area even though it exists in the ineffective touch area ITA beyond the boundary area BTA. For example, when the multi-touch is made, the boundary region may overlap. Accordingly, the filter tap may be located in one or two areas of touch raw data located in the invalid touch area ITA or touch raw data located in the effective touch area VTA. In this case, the filtering unit 44 moves the position of the filter tap to which the filtering is applied and filters (d) and (e) with the same weight or filters the weight with only (e).

Meanwhile, in the case of the touch raw data located in the ineffective touch area ITA which exists at a spaced position without contacting the boundary area BTA, the filtering is not performed as described above. That is, the filtering strength value TAS is set to "0".

Formulas for the above-described examples are shown in the table below. In Table 1, TAS is a filtering intensity value, a touch area is an effective touch area (VTA), a non-touch area is an invalid touch area (ITA), and a filter tab is a filter tab.

TABLE 1

Hereinafter, a method of driving an electronic device having a touch sensor according to an embodiment of the present invention will be described. However, reference is made to FIGS. 1 to 9 together to help understand the description.

10 is a schematic flowchart of a method of driving an electronic device having a touch sensor according to an exemplary embodiment of the present invention, and FIG. 11 is a detailed flowchart of determining filtering strength for each region.

As shown in FIG. 10, the method of driving an electronic device having a touch sensor according to an embodiment of the present invention includes obtaining touch raw data (S110), determining and varying the filtering intensity for each region (S120), and In operation S130, the coordinates of the touch input position may be calculated.

Obtaining touch raw data (S110) is a step of supplying a driving signal to the Tx lines of the touch screen (TSP) including the touch sensors and sensing the voltage change of the touch sensors through the Rx lines to obtain the touch raw data to be.

Determining and varying the filtering intensity for each region (S120) analyzes the touch raw data to determine the effective touch area (VTA) where the touch raw data exists, the invalid touch area (ITA) where the touch raw data does not exist, and the effective touch. A boundary area BTA existing between the area and the invalid touch area is defined and different filtering strengths are applied to the effective touch area VTA, the invalid touch area ITA, and the boundary area BTA.

Calculating the coordinates for the touch input position (S130) is a step of assigning an identification number to the touch raw data filtered for each region and calculating the coordinates for the touch input position.

In operation S120 of determining and varying the filtering strength, the filtering strength of the boundary area BTA is higher than that of the ineffective touch area ITA and the effective touch area VTA. At this time, the filtering on the invalid touch area ITA is not performed.

The step S120 of determining and varying the filtering intensity for each region is described in detail with reference to FIG. 11.

First, it is examined whether the filtering intensity value TAS corresponds to "0" (S121). If the filtering intensity value TAS is "0" (Y), since the filter corresponds to touch raw data for the invalid touch area ITA, the filtering is not performed (S126). At this time, if the filtering strength value TAS is not "0" (N), the flow advances to the next step.

Next, it is examined whether the filtering strength value TAS corresponds to "1" (S122). If the filtering intensity value TAS is "1" (Y), since it corresponds to the touch raw data for the effective touch area VTA, the effective touch area VTA or the invalid touch area ITA based on the boundary area BTA. In step S123, it is determined whether or not the touch raw data is present. If the filtering intensity value TAS is not "1" (N), the process proceeds to the next step.

If there is touch raw data located in the ineffective touch area ITA or the effective touch area VTA and in contact with the boundary area BTA (123a, 123b), the position of the filter tap is moved according to their position and the first filtering is performed. (S127)

Next, it is examined whether the filtering strength value TAS corresponds to "2" (S124). If the filtering intensity value TAS is "2" (Y), the number of data of the effective touch area VTA and the invalid touch area ITA adjacent to the boundary area BTA is compared (S125).

If the number of touch raw data located in the effective touch area VTA is greater than the ineffective touch area ITA with respect to the boundary area BTA (S125a), the effective touch area VTA adjacent to the boundary area BTA is determined. First filtering is performed so that the touch raw data is filtered with high weighting (S128a).

If the number of touch raw data of the invalid touch area ITA and the number of touch raw data located in the effective touch area VTA are large (S125b) based on the boundary area BTA, the effective area adjacent to the border area BTA is valid. The second filtering is performed to filter the touch raw data of the touch area VTA and the invalid touch area ITA with high weighting (S128b).

If the number of touch raw data of the invalid touch area ITA is greater than the number of touch raw data located in the effective touch area VTA based on the boundary area BTA (S125c), the valid area adjacent to the border area BTA is valid. Third filtering is performed to filter the touch raw data of the touch area VTA and the invalid touch area ITA with a high weight value (S128c).

The same filtering method as the embodiment of the present invention allows an adaptive smoothing filter that can reduce the throughput (or degradation) of the data while increasing linearity, which is approximately twice that of the average filter. It has a signal processing improvement effect.

The present invention has the effect of reducing the throughput (or degradation) of the data while minimizing the distortion of the signal and increasing the linearity by applying different filtering to locations where signal distortion is likely to occur and difficult locations. In addition, the present invention has the effect of providing an adaptive processing technique for efficiently removing the distortion of the signal appearing in the touch boundary region.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical configuration of the present invention described above may be modified in other specific forms by those skilled in the art to which the present invention pertains without changing its technical spirit or essential features. It will be appreciated that it may be practiced. Therefore, the embodiments described above are to be understood as illustrative and not restrictive in all aspects. In addition, the scope of the present invention is shown by the claims below, rather than the above detailed description. Also, it is to be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention.

50: host system 20: timing controller
12: data driving circuit 14: scan driving circuit
DIS: LCD panel TSP: Touch screen
30 and 40: touch screen driving circuit 42: filtering area defining unit
44: filtering unit 46: coordinate calculation unit
TA: Touch Area VTA: Effective Touch Area
ITA: Invalid touch area BTA: Boundary area

Claims (11)

A touch screen comprising touch sensors defined by Tx lines and Rx lines;
A touch sensing circuit configured to supply a driving signal to the Tx lines and to sense a voltage change of the touch sensors through the Rx lines to output touch raw data; And
Analyzing the touch raw data to define an effective touch area in which touch raw data exists, an invalid touch area in which touch raw data does not exist, and a boundary area existing between the valid touch area and the invalid touch area, And a touch coordinate detector for varying the filtering intensity of the touch raw data located in the effective touch region, the invalid touch region, and the boundary region, and calculating coordinates for the touch input position.
The touch coordinate detector
And a touch sensor having a filtering unit to increase the filtering intensity of the touch raw data located at the boundary area than the invalid touch area and the effective touch area. The method of claim 1,
The touch coordinate detector
A filtering region defining unit analyzing the touch raw data to define an effective touch region in which touch raw data exists, an invalid touch region in which touch raw data does not exist, and a boundary region existing between the valid touch region and invalid touch region Wow,
And a coordinate calculator configured to assign an identification number to the touch raw data filtered by the area and calculate a coordinate for a touch input position. delete The method of claim 1,
The filtering unit
The electronic device having a touch sensor, which does not perform filtering on touch raw data positioned in the invalid touch region. The method of claim 1,
The filtering unit
If the number of touch raw data located in the effective touch area is greater than the number of touch raw data in the invalid touch area based on the boundary area, the filter is placed with a higher weight on the touch raw data of the effective touch area adjacent to the border area. Electronic device having a touch sensor, characterized in that. The method of claim 1,
The filtering unit
If the number of touch raw data of the invalid touch area and the number of touch raw data located in the effective touch area are equal to each other based on the border area, the touch raw data of the valid touch area and the invalid touch area adjacent to the border area are included. Electronic device having a touch sensor characterized in that the filtering with a high weight. The method of claim 1,
The filtering unit
If the number of touch raw data of the invalid touch area is greater than the number of touch raw data located in the effective touch area with respect to the border area, the touch raw data of the valid touch area and the invalid touch area adjacent to the border area are included. Electronic device having a touch sensor characterized in that the filtering with a high weight. Supplying a driving signal to Tx lines of a touch screen including touch sensors and sensing a change in voltage of the touch sensors through Rx lines to obtain touch raw data;
The touch raw data is analyzed to define an effective touch area in which touch raw data exists, an invalid touch area in which touch raw data does not exist, and a boundary area existing between the valid touch area and the invalid touch area and defining the valid touch area. Determining and varying a filtering intensity for touch raw data located in the invalid touch region and the boundary region; And
Assigning an identification number to the touch raw data filtered by the area and calculating coordinates for the touch input position;
Determining and varying the filtering intensity
And a filtering intensity of the touch raw data located in the boundary area is higher than the ineffective touch area and the effective touch area. delete The method of claim 8,
Determining and varying the filtering intensity
And a method of performing filtering on the touch raw data located in the invalid touch region. The method of claim 1,
The filtering unit
And an adaptive smoothing filter for adaptively varying filtering strengths for touch raw data positioned in the effective touch region, the invalid touch region, and the boundary region.

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