KR20130095427A - Single layer capacitive type touch screen apparatus capable of multi touch - Google Patents

Abstract

PURPOSE: A touch screen device of a single layer capacitance method capable of multi-touch is provided to sense an accurate touch point when a plurality of points is simultaneously touched on a touch panel of a large screen. CONSTITUTION: A switch device (S1) and a switch device (S3) are connected to one end of individual signal electrode (120). A first integrator (231) and a second integrator (232) are individually connected to the switch device (S3) and a switch device (S4). A first analog-digital converter (ADC n) and a second analog-digital converter (ADC n') are individually connected to the first integrator and the second integrator. An applied power line (V1) and an applied power line (V2) are individually connected to a plurality of the switch devices (S1) and a plurality of the switch devices (S2). A switch control signal line (SW1) individually turns on or off the switch device (S1) included in each signal electrode from the switch device (S1) included in the other signal electrode. A switch control signal line (SW2) individually turns on or off the switch device (S2) included in each signal electrode from the switch device (S2) included in the other signal electrode.

Description

[0001] Description [0002] SINGLE LAYER CAPACITIVE TYPE TOUCH SCREEN APPARATUS CAPABLE OF MULTI TOUCH [0003]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a single layer capacitive touch screen device for controlling a voltage waveform applied to a signal electrode to reduce an interference signal generated by multiple finger touches to realize multi-touch.

The touch screen device is simple to input information, and is often used in mobile phones and monitors. Of the various techniques for implementing a touch screen, the capacitive type can be made into a single layer, and it can be attached directly on the display element, which is expected to be widely used in mobile phones because of its high transmittance.

Of the single-layer capacitive touch screen implementations, the pulse capacitive method, which measures the charge induced by the finger touching the other signal voltage across the rod-shaped signal electrode, And a multi-touch capable of recognizing multiple touch points at the same time.

The single-layer pulse capacitive touch screen panel has a structure in which a plurality of rectangular rod-shaped signal electrodes 120 are formed in parallel with the horizontal axis (X-axis). Prior Art 1 discloses a single-layer pulse capacitive touch screen panel. FIG. 1 is a cross-sectional view of a single-layer pulse capacitive touch screen panel 100, and FIG. 2 is a plan view of a single-layer pulse capacitive touch screen panel 100. Referring to FIG.

A major axis of the signal electrode 120 is formed on the substrate 110 in parallel with the X axis. The substrate 110 is formed of transparent plastic or tempered glass. The signal electrode 120 is made of a transparent and electrically conductive material such as ITO (Indium Tin Oxide), and the sheet resistance of the signal electrode 120 is usually 20 to 200? / Cm 2. A signal electrode 120 is formed on the substrate 110, and a protective film 111 is formed on the signal electrode. The finger 300 is brought into contact with the protective film.

3 is an explanatory diagram of a pulse capacitance method when the finger 300 is brought into contact with the signal electrode 120. FIG. Let the total length of the signal electrode be L and the position where the finger touches x. Let R be the resistance of the signal electrode from the left origin to x, and let R be the resistance from x to the end (the baseline). The signal electrode can be seen as an equivalent circuit in which resistors R and R 'are connected in series. Assuming that the sheet resistance of the signal electrode is uniform, the resistances R and R are established as shown in Equation (1).

Fingers can be seen with a grounded battery of several hundred pF. Therefore, the equivalent circuit of the pulse capacitance type is a structure in which the capacitor C corresponding to the finger is grounded between the resistors R and R of the signal electrode.

3 (A) is an equivalent circuit when the voltage waveform V is applied to the right end of the signal electrode and the left end is grounded. At this time We will call it the "+" frame. The charge Q (+) charged in the equivalent circuit capacitor C of the finger at the x position where the finger contacts the "+"

3 (B) is an equivalent circuit when the voltage waveform is changed and applied. This time is referred to as a "-" frame. The charge Q (-) charged in the equivalent circuit capacitor C of the finger at the x position where the finger touches the frame is expressed by Equation 3 below.

The position (x) of the contact point of the finger from the charge amounts Q (+) and Q (-) induced in the finger in the "+" frame and the "-" frame can be obtained by the following equation (4).

The Y axis at which the finger touches can be determined from the center of gravity of the amount of charge accumulated in the signal electrode. As shown in FIG. 4, if the distance between neighboring signal electrodes is P, the y-axis coordinate y which the finger touches is obtained by the following equation (5). Qn (+) and Qn (-) are the charges induced in the finger in the "+" frame and the "-" frame induced in the nth signal electrode.

5 is a configuration diagram of a touch screen apparatus of a pulse capacitance type. The touch screen device includes a touch screen panel 100 and a driving module 200. The driving module includes a control unit 210 for performing overall control, a driving unit 220 for applying a voltage waveform to the signal electrodes of the touch screen panel, a sensing unit 230 for sensing the amount of charges accumulated in the signal electrodes of the touch screen panel, And a signal processing unit 240 for processing the detection signal and switching to X and Y coordinates. It is needless to say that the signal processing unit 240 may be implemented in an external device without being implemented in the touch screen device. When voltage is applied from the driver to the signal electrode, the sensing unit and the signal electrode are electrically disconnected, and when detecting a signal, the driver and the signal electrode are electrically disconnected.

6 is an example of a conventional driving circuit of the pulse capacitance type. V1 and V2 are voltage waveforms applied to the left and right ends of the signal electrode. Each of the signal electrodes 120 has four switch elements S1, S2, S3, and S4. The switch element S1 connects / disconnects the signal electrode and the drive waveform V1, and the switch element S2 connects / disconnects the signal electrode and the drive waveform V2. The switch elements S3 and S4 connect / disconnect the signal electrode 120 and the integrators 231 and 232, respectively. The integrator 231 is composed of an operational amplifier OP amp, a capacitor, and a reset switch element S6. When the reset switch element opens (conducts), the charge in the capacitor of the integrator is discharged and initialized. Each signal electrode is connected to an integrator and an analog-to-digital converter (ADC). The ADC on each signal electrode is connected to a digital signal processor (DSP). In the DSP, the ADC value of each signal electrode is calculated and the touch position is determined. Switch elements S1 and S2 connected to all the signal electrodes and switch elements S5 and S6 connected to all the integrators are connected to the control signal SW. All switch elements S3 and S4 connecting the signal electrode and the integrator are connected to the control signal SW.

6, V1, V2, S1, and S2 are included in the driving unit 220, the control unit 210 includes SW and SW ', and the sensing unit 230, Includes S3, S4, and integrator and ADC. A DSP is included in the signal processing unit 240.

FIG. 7 is a timing chart for implementing FIG. 6. FIG. V1 and V2 are applied while changing the voltage level every frame. In the "+" frame, the V voltage is applied to V1 and the ground voltage is applied to V2. In the "-" frame, the ground voltage is applied to V1, and the V voltage is applied to V2.

The period during which the control signal SW is 1 is the time during which the charge is charged to the signal electrode by finger contact. When SW is 1, the S1 switch element and the S2 switch element connected to the signal electrode are opened (the conductive state), and the switch elements S5 and S6 of the integrator are opened (conducted) to discharge the charge existing in the capacitor of the integrator .

During the period when the control signal SW 'is 1, the switch elements S3 and S4 are opened (conducted), and the charge induced in the signal electrode moves to the capacitor of the integrator. The ADC operates during the period when Read signal is 1. During the "+" frame and the "-" frame, the charge of the finger induced to the signal electrode is measured once, and the position measurement is performed once from these two measured values.

FIG. 8 is a flowchart for determining the position of a conventional touch panel of a pulse capacitance type. When the touch screen panel is activated, it performs an initial background measurement. The background measurement means to measure the charge accumulated in the parasitic capacitance of the signal electrode in the absence of finger contact with the signal electrode. Measure the charge induced on the finger during the "+" and "-" frames and calculate the coordinates. Since the error is approximately ± 5% in one measurement, it is measured several times and the coordinates are determined by the average value. The measurement error is inversely proportional to the square root of the number of measurements. Comparing the average value measured 100 times with the one measured value, the error is reduced to about 10%.

A 20-inch touch screen with a sheet resistance of 200? / ?, a width of 8 mm, and a length of 40 cm has a resistance of about 10 k? Between both ends of the signal electrode. When the protective film is made of 0.3 탆 SiO 2 film, the capacitor of the signal electrode led to the finger is about 0.5 nF. Since the fingers are not a perfect ground, they are smaller than those considered as parallel plate batteries. In a circuit in which a resistance of 10 k? And a capacitance of 0.5 nF is connected in series, the time constant? Is about 5 占 퐏. Since about 98% of the signal electrodes are charged in three times of the time constant, the time taken to measure the signal voltage once by adding the time of charging the signal to the signal electrode and the discharge period during which the charge moves in the integrating system is 6 times Is required. Since two frames are required for one-time position measurement, the time required for one-time position measurement is about 60 μs. In this case, the frequency of the driving waveform is about 20 kHz at the maximum.

Fig. 9 is an explanatory view when two hands are touched to the signal electrode. The finger of the same point is in contact with point B of the (N-1) signal electrode and point A of the (N + 2) electrode. 10 is an equivalent circuit diagram showing mutual interference (cross-talk) when fingers are touched as shown in Fig. R1 is the resistance from the origin of the (N + 2) signal electrode to the point A, and R2 is the resistance from the point A to the right end. R3 is the resistance from the origin of the (N-1) signal electrode to the point B, and R4 is the resistance from the point B to the right end. The (N-1) signal electrode and the (N + 2) signal electrode should be completely electrically separated from each other, but the two electrodes are connected through the palm and the capacitor C1 is placed between the two electrodes. If the impedance generated by the capacitor is much larger than the resistance (R1 + R2, R3 + R4) across the signal electrode, mutual interference can be ignored. However, the larger the touch screen, the longer the signal electrode becomes, which increases the resistance across the signal electrode, which increases the possibility of being affected by the impedance caused by the capacitor. C is approximately 0.5 nf, and the impedance (Z) at the square wave driving frequency (f) 20 kHz is expressed by Equation (6) below.

  The voltage at point A at point A is different when the point A and point B are contacted at one point at different points of time and when two points are simultaneously contacted at the same point in time. That is, the voltage distribution of the signal electrode is distorted due to the connection between the two fingers of the human body and the palm of the hand, and when multi-touch occurs on the large-sized touch panel, the accurate touch point can not be detected.

Prior Art 1: Korean Patent Laid-Open No. 10-2011-0081474

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems and it is an object of the present invention to provide a driving module and a driving method for a touch screen apparatus of a monolayer capacitive type which can accurately detect touch points even when a plurality of points are touched simultaneously on a large- And to provide a driving method.

The above object of the present invention can be also achieved by a touch screen device comprising a touch screen panel having n rectangular signal electrodes at regular intervals on a substrate and a driving module for driving the touch screen panel, The switch module S1 and the switch device S3 connected to one end of each signal electrode and the switch device S2 and the switch device S4 connected to the other end, A first integrator connected to the switch element S3, a first analog-to-digital converter (ADCn) connected to the first integrator, a second integrator connected to the switch element S4, and a second integrator connected to the second integrator And a second analog-to-digital converter (ADC n '), which is connected to the switch element S1, and includes an application power supply line V1 connected to the plurality of switch elements S1, An applied power supply line V2 connected to the element S2, a switch control signal line SW1 for turning on / off the switch element S1 provided on each signal electrode independently of the switch element S1 provided on the other signal electrode, and on each signal electrode The switch control signal line SW1 for turning on / off the switch element S1 independently of the switch element S1 provided at the other signal electrode and the switch element S2 provided at each signal electrode independently of the switch element S2 provided at the other signal electrode. It is also achievable by the drive module of a single-layer pulse capacitance type touch screen device characterized by including a switch control signal line SW2 for turning on / off.

It is still another object of the present invention to provide a single-layer touch screen device having a touch screen panel having n rectangular bar-shaped signal electrodes at regular intervals on a substrate and a driving module for driving the touch screen panel, And applying a voltage V1 and a voltage V2 alternately to each of the signal electrodes in a state in which there is no finger contact while alternately applying voltages V1 and V2 to each of the signal electrodes, A first step of measuring the amount of charge, and a step of applying a voltage V1 and a voltage V2 alternately to both signal electrodes at the same time to calculate the amount of charge applied to all the signal electrodes, and the calculated amount of charge and the amount of parasitic charge And a second signal electrode for selecting a signal electrode having a subtracted value equal to or greater than a specific value and a signal electrode adjacent to the signal electrode, And a third step of sensing the touch position by alternately applying voltages V1 and V2 at both ends to the signal electrodes selected in the second step and calculating the amount of charges applied to the signal electrodes in the mutual direction Layer touchscreen device. ≪ RTI ID = 0.0 > [0031] < / RTI >

According to the driving module of the single-layer pulse capacitive touch screen device according to the present invention, multi-touch can be stably realized even in a touch screen device of a single electrode pulse capacitive type for a large screen. According to the touch measuring method of the single layer pulse capacitive touch screen device according to the present invention, it is possible to easily grasp the touch position up to the screen of 60 inches or more.

1 is a cross-sectional view of a touch panel 100 of a single layer pulse capacitance type.
FIG. 2 is a plan view of a single-layer pulse capacitive touch screen panel 100. FIG.
3 is an explanatory diagram of the operation of the touch screen panel of the pulse capacitance type.
4 is an explanatory diagram for calculating the Y axis coordinate of the pulse capacitance method.
5 is a configuration diagram of a touch screen apparatus of a pulse capacitance type.
6 is a driving circuit diagram of a conventional pulse capacitance type.
FIG. 7 is a timing chart for implementing FIG. 6. FIG.
FIG. 8 is a flowchart for determining the position of a conventional touch panel of a pulse capacitance type.
11 is a driving circuit diagram of an example of the pulse capacitance method of the present invention.
Figure 12 is an example of a timing chart of the system controlling Figure 11;
Fig. 13 is a flowchart showing the procedure of Fig.
Fig. 14 is an example of a timing chart of the system controlling Fig.
Fig. 15 is a flowchart showing the procedure of Fig.

The signal electrode 120 can be thickly coated to lower the resistance between both ends of the signal electrode. However, in this case, the transmittance is lowered. When the signal electrodes are sequentially driven one by one, the switch elements S1 and S2 connected to the respective signal electrodes are disconnected from the other signal electrodes, but the average number of times is reduced and the position accuracy is lowered. In the case of a 20-inch touch panel, if the signal electrode width is set to about 8 mm, the number of signal electrodes should be about 30. When all the signal electrodes are driven at the same time, the touch position can be measured about 20,000 times per second. If the coordinates are determined by averaging 100 times, it is possible to transmit about 200 touch coordinates per second. When the signal electrodes are sequentially driven one row at a time, each signal electrode is electrically independent and mutual interference does not occur, but about 6 times per second, which is the number of times of emission divided by the number of signal electrodes.

In the present invention, the electrical interference of the signal electrodes to be touched is eliminated, and the measurement error is reduced by maximizing the number of times of measurement. The signal electrodes are simultaneously driven to determine one or more touch regions, the signal electrodes corresponding to the respective touch regions are simultaneously driven, and the respective touch regions are sequentially driven.

Best Mode for Carrying Out the Invention Hereinafter, a preferred embodiment of a glass surface foreign matter inspection apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

11 is a driving circuit diagram of a single-layer pulse capacitive touch screen device according to an embodiment of the present invention. Each of the signal electrodes 120 has four switch elements S1, S2, S3, and S4. The switch element S1 connects / disconnects the signal electrode and the drive waveform V1, and the switch element S2 connects / disconnects the signal electrode and the drive waveform V2. The switch elements S3 and S4 connect / disconnect the signal electrode 120 and the integrators 231 and 232, respectively. The integrator consists of an operational amplifier (OP Amp), a capacitor, and a reset switch element (S6). When the reset switch element is opened (conducting), the charge accumulated in the capacitor of the integrator is discharged and initialized. The larger the touch screen, the more charge the integrator charges. The voltage output from the integrator is inversely proportional to the charge capacity of the integrator and is proportional to the amount of charge being charged. If the accumulator capacitance of the integrator is small, saturation voltage may be generated, so it is usually about 1 nF for 20 inches. The capacitor of 1 nF is required to be formed outside the driving IC chip because it requires a large area to be formed inside the IC (Integrated Circuits) chip.

And an integrator and an ADC are independently connected to each signal electrode. The ADC on each signal electrode is connected to the DSP. In the DSP, after receiving the ADC value of each signal electrode, the calculation is performed to calculate the position. Although the present invention is called a DSP in the present invention, it may be implemented in a single chip form or a circuit unit (signal processing unit) for processing a digital signal.

The switch elements S1 and S2 connected to the respective signal electrodes and the switch elements S5 and S6 connected to the integrators corresponding to the respective signal electrodes are connected to control signals SW1, SW2, SW3, ..., SWn for independently controlling the respective signal electrodes . The switch elements S3 and S4 for connecting the respective signal electrodes and the integrators corresponding to the respective signal electrodes are respectively connected to the control signals SW1 ', Sw2', SW3 '... SWn' for independently controlling the respective signal electrodes . The difference between FIG. 11 and FIG. 6 is that all the signal electrodes are simultaneously driven in FIG. 6, but they can be simultaneously driven in FIG. 11, and only one or a few lines can be selectively driven.

12 is an example of a timing chart for controlling the driving circuit diagram shown in FIG. In FIG. 11, the touch coordinates are determined by sequentially driving the touch area once. V1 and V2 are applied while changing the voltage waveform every frame. That is, during the "+" frame, the V voltage is applied to V1 and the ground voltage is applied to V2. During the "-" frame, the ground voltage is applied to V1, and the V voltage is applied to V2. V1 and V2 are 180 degrees out of phase.

When the control signals SW1, SW2, SW3, ... SWn become 1 at the same time, all the signal electrodes are charged. The S1 switch element and the S2 switch element connected to all the signal electrodes are opened (electrically connected) and charged, and the switch elements S5 and S6 of the integrator connected to the respective signal electrodes are opened (conducted) to initialize the capacitor of the integrator.

In the period in which the control signals SW1 ', Sw2', SW3 '.... SWn' are 1, the switch elements S3 and S4 are opened so that the charge induced in the signal electrode is transferred to the integrator capacitor. The ADC operates during the period when Read signal is 1. The amount of charge of the finger induced to the signal electrode once each during the "+" frame and the "-" frame is measured, and coordinate measurement is performed once from these two measurands.

In Fig. 12, the touch region is first determined. All the control signals SW1, SW2, SW3,... SWn are applied as 1 to open (conduct) switch elements S1, S2 connected to all the signal electrodes to charge all the signal electrodes. When the charging is completed, the control signals of SW1, SW2, SW3, ... SWn are set to 0, and the switching elements S1, S2 connected to all the signal electrodes are closed (shorted) to float the signal electrodes. Next, the control signals of SW1 ', SW2', SW3 '... SWn' are set to 1, and the switch elements S3 and S4 connected to all the signal electrodes are opened (conducting) To the capacitor of Then, the voltage of the capacitor of the integrator corresponding to each signal electrode is converted into a digital value by synchronizing with the Read signal, and the touch region is determined by calculating digital signal processing through DSP to determine which signal electrode the touch occurred.

The touch area is determined by detecting a signal electrode whose value obtained by subtracting the background signal from the measured value of the signal electrode is greater than a specific value. The touch region means a region including a signal electrode in which a touch is generated and a signal electrode adjacent to the signal electrode. In the present invention, a signal region having a maximum amount of touch charge is vertically added, Three were set as the basis.

12, it is assumed that a value obtained by subtracting the background signal from the measured value at the signal electrode 3 and the signal electrode 12 is greater than a specific value. Under this assumption, the first touch region is determined as the signal electrodes 2, 3, 4, and the second touch region is determined as the signal electrodes 11, 12, 13.

Next, the first touch area is driven and the touch areas are successively driven sequentially. 12, the first touch region corresponds to the second, third, and fourth signal electrodes, and the second touch region corresponds to the signal electrodes 11, 12, and 13. The touch coordinates (points) are determined by sequentially driving the first touch area and the second touch area, the touch area is set by driving all the signal electrodes again, and the set touch area is sequentially driven.

Fig. 13 is a flowchart showing the procedure of Fig. First, the background measurement is performed, and then the touch area is determined. The coordinates are calculated by successively measuring the determined touch area. If the measurement is not made by the number of repetition times (average number of times), the touch area determination step, the touch area sequential driving step, and the coordinate calculation step are sequentially repeated to increase the accuracy and then the coordinates are determined. To continue the measurement, the touch area determination step, the touch area sequential driving step, and the coordinate calculation step are sequentially performed again, and when the measurement is to be terminated, the process is terminated. The single layer pulse capacitance method has a measurement error of about 5% in one measurement. To reduce the measurement error to less than 1%, approximately 100 measurements should be performed and averaged. Assuming that about 100 measurements are performed for accurate coordinate determination, the timing diagram and the flowchart shown in Figs. 11 and 12 are ineffective because a step of determining the touch area is required to be performed each time one touch coordinate is calculated .

Therefore, the timing diagram of FIG. 14 and the flowchart of FIG. 15 are proposed in a more improved manner. In Figs. 14 and 15, it is highly accurate to determine the touch coordinates after determining the touch area and repeatedly measuring only the determined touch area several times. 14 is a timing chart for determining a touch area once and driving the determined touch area in a repeated sequence. 14, the first touch region corresponds to the second, third, and fourth signal electrodes, and the second touch region corresponds to the signal electrodes 11, 12, and 13.

Fig. 15 is a flowchart showing the procedure of Fig. First, the background measurement is performed, and then the touch area is determined. The determined touch areas are sequentially driven to calculate coordinates, and the average number of measurements is checked. If the number of measurements is less than the average number of measurements, the touch area sequential driving step and the coordinate calculation step are repeated. When the average number of measurements is reached, the coordinates are determined by averaging the calculated coordinates. If it is desired to continue measurement, it is performed again from the touch region determination step as shown in the flowchart.

While specific embodiments of the invention have been illustrated and described, it will be obvious that the same may be varied in many ways by those skilled in the art without departing from the spirit of the invention. Such modified embodiments should not be individually understood from the spirit and scope of the present invention, but rather should be regarded as falling within the scope of the appended claims.

The present invention improves the accuracy of the multitouch function in a large screen touch screen. It can be used as a touch screen for monitors for casino or gaming machines where multi-touch functionality is important.

100: Pulse Capacitive touch screen panel
110: substrate 111: protective film
120: signal electrode 200: drive module
210: controller 220: driver
230: sensing unit 231, 232: integrator
240: Signal processor

Claims (7)

Layer touch screen device having a touch screen panel having n rectangular bar-shaped signal electrodes at regular intervals on a substrate and a driving module for driving the touch screen panel, wherein voltage V1 and voltage V2 The driving module determining the touch position while alternately applying the driving signal,
A switch element S1 and a switch element S3 connected to one end of each signal electrode, a switch element S2 and a switch element S4 connected to the other end, a first integrator connected to the switch element S3, (ADC n), a second integrator coupled to the switch element S4, and a second analog-to-digital converter (ADC n ') coupled to the second integrator,
An applied power supply line V1 connected to the plurality of switch elements S1,
An applied power line V2 connected to the plurality of switch elements S2,
A switch control signal line SW1 for turning on / off the switch element S1 provided at each of the signal electrodes independently of the switch element S1 provided at the other signal electrodes;
A switch control signal line SW1 for turning on / off the switch element S1 provided for each of the signal electrodes independently from the switch element S1 provided for other signal electrodes,
And a switch control signal line (SW2) for turning on / off the switch element (S2) provided on each signal electrode independently from the switch element (S2) provided on the other signal electrode. module.
2. The apparatus of claim 1, wherein the drive module
And a signal processing unit for calculating a touch position after receiving output values output from the first analog-to-digital converter (ADC n) and the second analog-digital converter (ADC n ') provided at the respective signal electrodes A driving module of a single layer pulse capacitive touch screen device.
3. The method according to claim 1 or 2,
Wherein the first integrator and the second integrator include a capacitor,
The switch elements S1, S2, S3, S4, the first integrator, the first analog-to-digital converter (ADC n), the second integrator, the second analog-to-digital converter (ADC n '), The applied power supply line V1, the applied power supply line V2, the switch control signal line SW1, the switch control signal line SW1, and the switch control signal line SW2 are composed of at least one integrated circuit chip region and a non-integrated circuit region, and the capacitor is the non-integrated. The driving module of the single-layer pulse capacitance touch screen device, characterized in that provided in the circuit area.
A single-layer touch screen device comprising a touch screen panel having n rectangular bar-shaped signal electrodes on a substrate at regular intervals and a driving module for driving the touch screen panel are alternately applied with voltages V1 and V2 across the signal electrodes To determine a touch position, the method comprising:
A first step of measuring the amount of parasitic charge applied to each signal electrode while alternately applying voltages V1 and V2 to both ends of the signal electrodes in the absence of finger contact;
The voltages V1 and V2 are alternately applied to both signal electrodes at the same time, thereby calculating the amount of charge applied to all signal electrodes, subtracting the calculated charge amount and the parasitic charge amount calculated in the first step, and subtracting the value. A second step of selecting a signal electrode having a stationary abnormality and a signal electrode adjacent to the signal electrode;
And a third step of sensing the touch position by alternately applying voltages V1 and V2 to both the signal electrodes selected in the second step at the same time and calculating the amount of charge applied to the mutual signal electrodes Method of driving pulsed capacitive of a single layer touch screen device.
5. The method of claim 4,
Two or more signal electrodes having a value less than or equal to a specific value subtracted in the second step are detected, and one of the first signal electrode and the signal electrodes neighboring the first signal electrode are called first region signal electrodes, When the second signal electrode and the signal electrodes neighboring the second signal electrode are referred to as second area signal electrodes,
In the third step,
A third step of sensing the touch position by alternately applying voltages V1 and V2 at both ends to the first area signal electrode at the same time and calculating the amount of charge applied to the mutual signal electrodes,
And (3-2) sensing the touch position by applying voltages V1 and V2 to both terminals of the second area signal electrode at the same time, and calculating the amount of charge applied to the signal electrodes. A method of driving a pulse capacitance of a layer touch screen device.
6. The method of claim 5,
And a fourth step of determining a touch position by averaging the values repeatedly performed after repeating the second step, the third step, and the third step, by a predetermined number of times of repetition Method of driving pulsed capacitive of a single layer touch screen device.
6. The method of claim 5,
Further comprising a fifth step of determining a touch position by averaging the values repeatedly performed after repeating the steps 3-1 and 3-2 for the preset number of times of repetition, A method of driving a pulsed electrostatic capacity of a device.

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