KR20130016894A - Display having touch sensor - Google Patents

Abstract

PURPOSE: A display device with a touch sensor is provided to improve a touch frame rate by reducing sensing time without the deterioration of touch performance. CONSTITUTION: A plurality of driving electrode lines function as driving channels(Ta,Tb,Tc). A plurality of receiving electrode lines function as receiving channels(Ra,Rb,Rc). Touch sensors are formed by combining the plurality of receiving channels with the plurality of driving channels to implement a plurality of channel combinations. A touch sensor driving circuit differently generates a touch sensor driving pulse according to the channel combination or driving channel and supplies the touch sensor driving pulse to the driving electrode lines. A touch sensor reading circuit samples touch sensors and converts the sampled result into digital touch data. [Reference numerals] (AA,BB,CC,GG,HH,II,MM,NN,OO) Driving pulse; (DD,EE,FF,JJ,KK,LL,PP,QQ,RR) Charging waveform

Description

Display device with touch sensor {DISPLAY HAVING TOUCH SENSOR}

The present invention relates to a display device having a touch sensor.

User input means has been replaced with a touch screen in a button-type switch in accordance with the trend of lightening and slimming of household appliances and portable information devices. The touch screen applied to the display device includes a plurality of touch sensors. The touch sensors may be embedded in an in-cell type or coupled to the display panel. Resistive type, capacitive type and electro magnetic type are known as in-cell touch sensors. Among them, the touched part is detected by sensing the position where the capacitance change has occurred. Capacitive sensing is widely used.

The capacitive touch sensors include a plurality of driving electrode lines Tx and a plurality of receiving electrode lines Rx formed to cross each other. Mutual capacitors Cm are generated at the intersections of the driving electrode line Tx and the receiving electrode line Rx as shown in FIG. 1A. When the finger contacts the touch sensor as shown in FIG. 1B, the electric field between the electrode lines Tx and Rx is partially blocked, thereby lowering the charge amount of the mutual capacitor Cm. Therefore, the display device having the touch sensor can recognize the touch by measuring the change in the charge amount of the mutual capacitor Cm before and after the touch.

Recently, in response to an increase in the size of a touch screen including touch sensors and requiring multiple repetitive sensing for each touch frame for more accurate sensing, the response speed of the touch becomes a big issue. It is known that the touch frame rate required for smooth touch response is at least 60 Hz.

As the size of the touch screen increases, the number of driving channels (driving electrode lines) and receiving channels (receiving electrode lines) for configuring touch sensors increases, so the number of sensing points which are their intersection points also increases. Time constants for each channel in the touch screen are different from each other. The time constant is an indicator of how fast or slow the response can be to the input, which is proportional to the product of the channel's line resistance and capacitance. The smaller the time constant, the faster the response. On the contrary, the larger the time constant, the slower the response. In the touch screen, the short path channel has a small time constant, and the long path channel has a large time constant.

Charging and discharging characteristics of the driving pulse applied to the driving channel and the channel-specific mutual capacitor are shown in FIG. 2. When the driving pulse of the high level (H) is applied to the driving electrode line (Tx), the charge is charged to the mutual capacitor (Cm), and when the driving pulse of the low level (L) is applied to the driving electrode line (Tx), the mutual capacitor ( The charge of Cm) is discharged. Since the charge and discharge time of the mutual capacitor is proportional to the time constant, the charge and discharge time of the mutual capacitor is long when the path of the driving channel and the receiving channel is long, and the charge and discharge time of the mutual capacitor is short when the path of the driving channel and the receiving channel is short.

Assume that the driving channels Ti, Tj, Tk and the receiving channels Ri, Rj, Rk are arranged as shown in FIG. 3 to configure channel combinations for generating the mutual capacitor Cm. Shortest. The channel combination corresponding to the path is Ti-Rk, the channel combination in the path is Tj-Rj, and the channel combination corresponding to the path is Tk-Ri. When the driving pulses applied to the driving channels Ti, Tj, and Tk are collectively matched to the maximum time constant of the path, i.e., the time constant of the Ti-Rk channel combination with the longest path, as shown in FIG. Although channel combinations are given sufficient time for charging, the overall sensing time is increased and the touch frame rate is reduced. When the driving pulses applied to the driving channels Ti, Tj, and Tk are collectively matched to the minimum time constant of the path ③, that is, the time constant of the Tk-Ri channel combination with the shortest path, as shown in FIG. As a result, the charging amount of other channel combinations with a long path is reduced, so that the sensing signal is weak and the touch performance is deteriorated.

In the prior art, although the time constants are different for each channel combination, driving pulses having the same period are applied to all the driving channels collectively. Accordingly, in the related art, as described above, the amount of charge charged in the mutual capacitor is insufficient, so that the signal to noise ratio (SNR) is low, or the sensing time is increased, thereby reducing the touch frame rate.

Accordingly, an object of the present invention is to provide a display device having a touch sensor capable of improving the touch frame rate by reducing the sensing time without degrading the touch performance.

In order to achieve the above object, a display device having a touch sensor according to an embodiment of the present invention includes a plurality of drive electrode lines that function as drive channels; A plurality of receiving electrode lines intersecting with the driving electrode lines to function as receiving channels and implementing touch sensors by forming a plurality of channel combinations with the driving channels; A touch sensor driving circuit for generating a touch sensor driving pulse differently for each of the channel combinations or the driving channels and supplying the touch sensor driving pulses to the driving electrode lines; And a touch sensor reading circuit for sampling the touch sensors through the receiving electrode lines and converting the touch sensors into digital touch data.

The driving electrode lines and the receiving electrode lines cross each other, and mutual capacitors are formed at the intersections thereof.

In response to the time constant being changed according to a sensing position at which the mutual capacitor is formed, the touch sensor driving circuit changes at least one of a period of the touch sensor driving pulse and a pulse width of a high level for each channel combination, and then A plurality of repetitions are supplied to each of the channel combinations.

The pulse width of the high level of the touch sensor driving pulse is increased in proportion to the distance between the crossing portion and the touch sensor driving circuit; The pulse width of the low level of the touch sensor driving pulse is increased in proportion to the distance between the crossing portion and the touch sensor readout circuit.

The touch sensor readout circuit sequentially samples each of the touch sensors positioned in the channel combinations a plurality of times.

The touch sensor driving circuit changes the period of the touch sensor driving pulse for each driving channel in response to the time constant being changed according to the sensing position at which the mutual capacitor is formed.

The pulse width of the high level of the touch sensor drive pulse is the same in the drive channels; The pulse width of the low level of the touch sensor driving pulse is increased in proportion to the distance between the crossing portion and the touch sensor readout circuit.

The touch sensor reading circuit samples a plurality of touch sensors simultaneously on the same driving channel.

According to the present invention, the touch drive time is optimally allocated to each channel to reduce unnecessary driving time, thereby reducing the sensing time, thereby greatly improving the touch frame rate without degrading the touch performance. When the touch frame rate is improved, the touch response is faster and smoother.

1A and 1B are views illustrating an operation before and after touch of capacitive touch sensors;
2 is a diagram illustrating charge and discharge characteristics of a driving pulse applied to a driving channel and a channel-specific mutual capacitor.
3 illustrates an example of a channel combination configuration of a driving channel and a receiving channel for generating a mutual capacitor.
4 illustrates a problem when the same drive pulse is collectively applied to all drive channels.
5 illustrates a display device having a touch sensor according to an exemplary embodiment of the present invention.
FIG. 6 is an equivalent circuit diagram illustrating a part of a pixel array and touch sensors formed in the display panel shown in FIG. 5. FIG.
7 illustrates an example of driving channels and receiving channels formed on a display panel.
FIG. 8A is a diagram showing an experimental result of a time constant for each position in a specific reception channel. FIG.
FIG. 8B is a view showing the results of experiments on time constants by position in a specific drive channel. FIG.
9 illustrates channel combinations of a drive channel and a receive channel for generating a mutual capacitor.
10 and 11 illustrate at least one of a period of a touch sensor driving pulse and a high level pulse width for each channel combination according to a first embodiment of the present invention;
FIG. 12 is a diagram illustrating that a period of a touch sensor driving pulse is changed for each driving channel according to a second embodiment of the present invention. FIG.
FIG. 13 is a graph showing a time and a touch frame rate for one touch frame according to the present invention in comparison with each other.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 5 to 13.

The display device of the present invention is a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), an organic light emitting diode display (Organic Light Emitting Display) , OLED), electrophoretic display (EPD), and the like, and touch sensors formed in or coupled to the display panel of the flat display device. In the following embodiments, as an example of a flat panel display element, a liquid crystal display element is described, but it should be noted that the display device of the present invention is not limited to the liquid crystal display element.

5 shows a display device having a touch sensor according to an embodiment of the present invention. FIG. 6 is an equivalent circuit diagram illustrating a part of a pixel array and touch sensors formed in the display panel shown in FIG. 5.

Referring to FIG. 5, a display device according to an exemplary embodiment of the present invention may include a display panel 100, a display data driver circuit 202, a display scan driver circuit 204, a touch sensor driver circuit 302, and a touch sensor readout. A touch sensor read-out circuit 304, a touch controller 306, a timing controller 400, and the like.

In the display panel 100, a liquid crystal layer is formed between two glass substrates. The lower substrate of the display panel 100 includes a plurality of data lines D1 to Dm and m is a positive integer, and a plurality of gate lines G1 to Gn intersecting the data lines D1 to Dm are positive. ), A plurality of TFTs (Thin Film Transistor, TFT of FIG. 6) and liquid crystal cells (Clc of FIG. 6) formed at intersections of the data lines D1 to Dm and the gate lines G1 to Gn. ) Includes a plurality of pixel electrodes 11 for charging the data voltages, storage capacitors (Cst of FIG. 6), touch sensors, etc., connected to the pixel electrodes 11 to maintain the voltage of the liquid crystal cell. do.

As illustrated in FIG. 6, the touch sensors intersect the driving electrode lines T0 to Tj parallel to the gate lines G1 to Gn, and j is a positive integer smaller than n, and the driving electrode lines T0 to Tj. Receive electrode lines R0 to Ri parallel to the lines D1 to Dm, i is a positive integer smaller than m, and the intersection of the driving electrode lines T0 to Tj and the receiving electrode lines R0 to Ri. And a mutual capacitor Cm formed in the portion. Touch sensor driving pulses for driving the touch sensor are supplied to the driving electrode lines T0 to Tj, and touch reference voltages are supplied to the receiving electrode lines R0 to Ri. The driving electrode lines T0 to Tj function as driving channels for applying a touch sensor driving pulse to the mutual capacitors Cm, and the receiving electrode lines R0 to Ri may include the mutual capacitors Cm and the touch sensor. It functions as receive channels for connecting the readout circuit 304. In FIG. 6, 'Tx' represents any one of the driving electrode lines T0 to Tj, and 'Rx' represents any one of the receiving electrode lines R0 to Ri.

The pixels of the display panel 100 are formed in a pixel area defined by the data lines D1 to Dm and the gate lines G1 to Gn, and are arranged in a matrix form. The liquid crystal cell of each pixel is driven by an electric field applied according to the voltage difference between the data voltage applied to the pixel electrode 11 and the common voltage Vcom applied to the common electrode 12 to adjust the amount of incident light transmitted. . The TFTs are turned on in response to the gate pulses from the gate lines G1 to Gn to supply the voltage from the data lines D1 to Dm to the pixel electrode 11 of the liquid crystal cell.

The upper substrate of the display panel 100 may include a black matrix, a color filter, and the like. The lower glass substrate of the display panel 100 may be implemented with a color filter on TFT (COT) structure. In this case, the black matrix and the color filter may be formed on the lower glass substrate of the display panel 100. The common electrode 12 is formed on the upper glass substrate in a vertical electric field driving method such as twisted nematic (TN) mode and vertical alignment (VA) mode, and is similar to an in plane switching (IPS) mode and a fringe field switching (FFS) mode. In the horizontal electric field driving method, the pixel electrode 11 is formed on the lower substrate. The common voltage Vcom supplied to the common electrode 12 may be a DC voltage between 7V and 8V.

Polarizing plates are attached to each of the upper and lower substrates of the display panel 100, and an alignment layer for setting the pretilt angle of the liquid crystal is formed on an inner surface of the display panel 100 in contact with the liquid crystal. A column spacer may be formed between the upper substrate and the lower substrate of the display panel 100 to maintain a cell gap of the liquid crystal cell.

The display data driving circuit 202 includes a plurality of source drive integrated circuits (ICs). The source drive ICs latch the digital video data RGB input from the timing controller 400. The source drive ICs convert the digital video data (RGB) into analog positive / negative gamma compensation voltages and output analog video data voltages. The analog video data voltage is supplied to the data lines D1 to Dm.

The display scan driver circuit 204 includes one or more scan drive ICs. The scan drive IC sequentially supplies scan pulses (or gate pulses) synchronized with the analog video data voltages to the gate lines G1 to Gn under the control of the timing controller 400 to write the analog video data voltages. Select a line. The scan pulse is generated as a pulse swinging between the gate high voltage and the gate low voltage. The gate high voltage VGH may be a voltage of approximately 18V to 20V, and the gate low voltage VGL may be a voltage of approximately 0V to 15V.

The touch sensor driving circuit 302 generates a touch sensor driving pulse based on the first touch sensor timing control signal Ctx applied from the outside and sequentially applies the touch sensor driving pulses to the driving electrode lines T0 to Tj. The touch sensors are scanned, and N (N is a positive integer of 2 or more) times or more is output to each of the driving electrode lines T0 to Tj to output the touch sensor driving pulses. Therefore, the touch sensor driving circuit 302 supplies the touch sensor driving pulse to the front driving electrode line (eg, Tj-2) at least N times, and then applies the touch sensor driving pulse to the current driving electrode line (Tj-1). N times or more are supplied, and then touch sensor drive pulses are supplied N or more times to the next stage driving electrode line Tj. The touch sensor driving circuit 302 completes the touch scanning operation once from the first driving electrode line T0 to the last driving electrode line Tj through this supply method. Thus, the time required for the touch sensor driving circuit 302 to complete the touch scanning operation once becomes one touch frame. The touch sensor driving circuit 302 may be implemented as a scan drive IC having a circuit configuration substantially the same as that of the scan drive IC of the display scan driving circuit 204. The timing at which the touch sensor driving circuit 302 is operated may overlap or non-overlap at the timing at which the display scan driving circuit 204 is operated.

The touch sensor driving pulses supplied from the touch sensor driving circuit 302 vary for each channel combination or for each driving channel for forming the mutual capacitor Cm. In the touch sensor driving circuit 302 as shown in FIGS. 10 and 11, the time constant RC is changed according to a sensing position at which the mutual capacitor Cm is formed, as shown in FIGS. 7 and 8A and 8B. At least one of a period of the touch sensor driving pulse and a high level pulse width may be different for each channel combination formed by the intersection of the channel and the reception channel. In addition, the touch sensor driving circuit 302 may vary the period of the touch sensor driving pulse for each driving channel as shown in FIG. 12 in consideration of the time constant RC being changed according to the sensing position.

The touch sensor read circuit 304 supplies a touch reference voltage to the receiving electrode lines R0 to Ri based on the second touch sensor timing control signal Crx applied from the outside. The touch reference voltage may be set to a DC voltage higher than 0V and lower than 3V. The touch sensor readout circuit 304 samples and amplifies the analog output of the touch sensors input through the reception electrode lines R0 to Ri, that is, the charge amount of the mutual capacitor Cm, and converts the digital output data into digital touch data. Send to 306. Here, the touch sensor read circuit 304 repeatedly samples the output of each touch sensor N times within one touch frame by supplying N times of the touch sensor driving pulses.

The touch controller 306 stores digital touch data repeatedly input N times from the touch sensor reading circuit 304 in a memory. The touch controller 306 calculates digital touch data repeatedly output N times from the same touch sensor, and reduces the noise component mixed in the digital touch data based on the calculation result. The touch controller 306 detects touch data equal to or greater than the reference value by comparing digital touch data having reduced noise components with a preset reference value. The touch controller 306 analyzes touch data over a reference value using a preset touch recognition algorithm and calculates coordinate values of touched touch sensors. The coordinate value data of the touch position output from the touch controller 306 is transmitted to the external host system as touch digital touch data in the HID format. The host system executes an application program associated with the coordinate value of the touch position.

The timing controller 400 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 input from an external host system. Display timing control signals for controlling the operation timing of the display data driver circuit 202 and the display scan driver circuit 204 are generated. The timing control signal of the display scan driving circuit 204 includes a gate start pulse (GSP), a gate shift clock (GSC), a gate output enable signal (Gate Output Enable, GOE), and the like. . The timing control signal of the display data driving circuit 202 includes a source sampling clock (SSC), a polarity control signal (Polarity, POL), a source output enable signal (SOE), and the like.

The timing controller 400 enables the outputs of the display data driver circuit 202 and the display scan driver circuit 204 to display video data on the pixels during the display period. The timing controller 400 enables the output of the touch sensor driving circuit 302 and enables the touch signal sampling of the touch sensor reading circuit 304 during the touch sensor driving period. The display period and the touch sensor driving period may overlap each other or may not overlap each other, and may be appropriately adjusted in consideration of panel characteristics according to the type of the display panel 100.

FIG. 7 illustrates an example of driving channels T0 to T20 and receiving channels R0 to R18 formed on the display panel 100. FIG. 8A shows a table and a graph of the results of the time constants (RC) for each position in a specific receiving channel (R1), and FIG. 8B shows the results of the time constants (RC) for each position in a specific drive channel (T20). Is shown in tables and graphs.

In FIG. 7, the reception channels R0 to R18 are arranged in the order of R0 to R18 according to the distance from the touch sensor driving circuit 302, and the driving channels T0 to T20 are the touch sensor reading circuit 304. ) Are arranged in order of T0 ~ T20 according to the distance from them.

As shown in FIG. 8A, the time constant RC is increased in proportion to the distance D between the point where the mutual capacitor is generated and the touch sensor read circuit 304 in the first receiving channel R1. The reception path is longer at the point crossing T20 than the point crossing T0 in the first reception channel R1. As the receive path gets longer, the time constant in the receive channel increases. Therefore, the time constant RC in the first reception channel R1 is the smallest at 90 ns in the T0-R1 channel combination and the largest at 260 ns in the T20-R1 channel combination.

As shown in FIG. 8B, in the twentieth driving channel T20, the time constant RC is increased in proportion to the distance D between the point where the mutual capacitor is generated and the touch sensor driving circuit 302. The driving path is longer at the point intersecting with R18 than at the point intersecting with R0 in the twentieth drive channel T20. As the drive path gets longer, the time constant in the drive channel increases. Therefore, the time constant RC in the twentieth drive channel T20 is the smallest at 80 ns in the T20-R0 channel combination, and the largest at 240 ns in the T20-R18 channel combination.

9 shows channel combinations of the driving channels Ta, Tb, and Tc and the receiving channels Ra, Rb, and Rc for generating the mutual capacitor Cm.

In Fig. 9, the direction "X" indicates a direction further away from the touch sensor driving circuit, and the direction "Y" indicates a direction further away from the touch sensor reading circuit. Accordingly, the channel combinations formed by the intersection of the driving channels Ta, Tb, and Tc and the receiving channels Ra, Rb, and Rc have different lengths of the signal transmission path. In other words, the time constants of the channel combinations are all different. Among the channel combinations, the channel combination with the smallest time constant is Tc-Ra, and the channel combination with the largest time constant is Ta-Rc.

10 and 11 illustrate that at least one of a period of a touch sensor driving pulse and a high level pulse width varies for each channel combination according to the first embodiment of the present invention.

10 and 11 will be described with reference to FIG. 9.

In the channel combinations Ta-Ra, Ta-Rb, and Ta-Rc constituted by the intersection of the driving channel Ta and the receiving channel Ra, Rb, and Rc, the sensing signal transmission paths have the same length as the first value. The driving signal transmission paths are different in length. The channel combinations Tb-Ra, Tb-Rb, and Tb-Rc constituted by the intersection of the driving channel Tb and the receiving channels Ra, Rb, and Rc are each a second signal whose path length of the sensing signal transmission path is smaller than the first value. Although the values are the same, the driving signal transmission paths have different lengths. The channel combinations Tc-Ra, Tc-Rb, and Tc-Rc constituted by intersections of the driving channel Tc and the receiving channels Ra, Rb, and Rc may be configured to have a third sensing signal transmission path having a length smaller than a second value. Although the values are the same, the driving signal transmission paths have different lengths.

In the first embodiment of the present invention, at least one of the period of the touch sensor driving pulse and the high level pulse width is changed for each channel combination in order to improve the touch frame rate by reducing the sensing time without degrading the touch performance.

To this end, the touch sensor driving circuit uses a touch sensor driving pulse having a high level H of the first pulse width H1 and a low level L of the first pulse width L1 as one period in the Ta-Ra channel combination. Can be authorized. The touch sensor driving circuit includes a high level H of the second pulse width H2 and a low level L of the first pulse width L1 for one cycle in the Ta-Rb channel combination. The touch sensor driving pulse can be applied. The touch sensor driving circuit includes a high level H of the third pulse width H3 and a low level L of the first pulse width L1 for one cycle in the Ta-Rc channel combination. The touch sensor driving pulse can be applied.

The touch sensor driving circuit uses the high level H of the first pulse width H1 and the low level L of the second pulse width L2 narrower than the first pulse width L1 in one cycle in the Tb-Ra channel combination. The touch sensor driving pulse can be applied. The touch sensor driving circuit may apply a touch sensor driving pulse having the high level H of the second pulse width H2 and the low level L of the second pulse width L2 as one cycle to the Tb-Rb channel combination. have. The touch sensor driving circuit may apply a touch sensor driving pulse having the high level H of the third pulse width H3 and the low level L of the second pulse width L2 as one cycle to the Tb-Rc channel combination. have.

The touch sensor driving circuit has a high level H of the first pulse width H1 and a low level L of the third pulse width L3 narrower than the second pulse width L2 in the Tc-Ra channel combination. The touch sensor driving pulse can be applied. The touch sensor driving circuit may apply a touch sensor driving pulse having the high level H of the second pulse width H2 and the low level L of the third pulse width L3 as one cycle to the Tc-Rb channel combination. have. The touch sensor driving circuit may apply a touch sensor driving pulse having a high level H of the third pulse width H3 and a low level L of the third pulse width L3 as one cycle to the Tc-Rc channel combination. have.

When the touch sensor driving pulse is applied in this way, the time can be optimally distributed according to the time required for charging for each channel combination, thereby effectively reducing the sensing time without deteriorating touch performance. As described above, varying at least one of the period of the touch sensor driving pulse and the high level pulse width for each channel combination is effective for sequentially sampling each of the touch sensors corresponding to the channel combination in the touch sensor readout circuit. .

12 shows that the period of the touch sensor driving pulse is changed for each driving channel according to the second embodiment of the present invention.

In the second embodiment of the present invention, in order to improve the touch frame rate by reducing the sensing time without degrading the touch performance, the period of the driving pulse is different for each driving channel while maintaining the same pulse width of the high level of the touch sensor driving pulse. do.

To this end, the touch sensor driving circuit applies the high level H of the fourth pulse width H4 and the low level L of the fourth pulse width L4 to the Ta driving channel having a length of the sensing signal transmission path. The touch sensor drive pulse can be applied at one cycle. The touch sensor driving circuit includes a fifth pulse narrower than the high level H and the fourth pulse width L4 of the fourth pulse width H4 in the Tb driving channel having a second value of which the sensing signal transmission path is smaller than the first value. The touch sensor driving pulse having the low level L of the width L5 as one cycle may be applied. The touch sensor driving circuit may include a sixth pulse narrower than the high level H and the fifth pulse width L5 of the fourth pulse width H4 in the Tc driving channel, the length of which the sensing signal transmission path is smaller than the second value. The touch sensor driving pulse having the low level L of the width L6 as one cycle may be applied.

When the touch sensor driving pulse is applied in this way, the time can be optimally distributed according to the time required for charging for each channel combination, thereby effectively reducing the sensing time without deteriorating touch performance. As described above, varying the period of the touch sensor driving pulse for each channel combination is effective for simultaneously sampling touch sensors existing on the same driving channel in the touch sensor readout circuit.

FIG. 13 is a graph showing a time and a touch frame rate for one touch frame according to the present invention, respectively.

FIG. 13 illustrates an experimental result when a touch is detected by accumulating 10 reception values for each channel combination for 24 driving channels and 32 reception channels embedded in a 10.1-inch display panel. As can be seen from the experimental results of FIG. 13, in the prior art in which driving pulses of the same period are applied to all driving channels collectively, the time required for one touch frame is measured to be approximately 0.017 seconds, and as a result, the touch frame rate is 60 frames. / Seconds. In contrast, in the first embodiment of the present invention in which at least one of the period of the touch sensor driving pulse and the high level pulse width is different for each channel combination, the time required for one touch frame is measured to be approximately 0.011 seconds, and as a result, the touch frame rate Was 91 frames / sec, a 52% improvement over the prior art. In addition, in the second embodiment of the present invention in which the period of the driving pulse is changed for each driving channel, the time required for one touch frame is measured to be approximately 0.014 seconds, and as a result, the touch frame rate is 70 frames / sec, which is 17% higher than the conventional method. Could know.

As described above, the present invention can optimally allocate the touch driving time to each channel to reduce unnecessary driving time and thereby reduce the sensing time, thereby greatly improving the touch frame rate without degrading the touch performance. If the touch frame rate is improved, the touch response is faster and smoother.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

100: display panel 202: display data driving circuit
204: display scan driving circuit 302: touch sensor driving circuit
304: touch sensor readout circuit 306: touch controller
400: Timing Controller

Claims (8)

A plurality of drive electrode lines functioning as drive channels;
A plurality of receiving electrode lines intersecting with the driving electrode lines to function as receiving channels and implementing touch sensors by forming a plurality of channel combinations with the driving channels;
A touch sensor driving circuit for generating a touch sensor driving pulse differently for each of the channel combinations or the driving channels and supplying the touch sensor driving pulses to the driving electrode lines; And
And a touch sensor reading circuit for sampling the touch sensors through the receiving electrode lines and converting the touch sensors into digital touch data. The method of claim 1,
The display device having a touch sensor, wherein the driving electrode lines and the receiving electrode lines cross each other, and mutual capacitors are formed at an intersection thereof. The method of claim 2,
The touch sensor driving circuit,
In response to the time constant being changed according to the sensing position at which the mutual capacitor is formed, after changing at least one of the period of the touch sensor driving pulse and the high level pulse width for each channel combination, a plurality of times each of the channel combinations is performed. Display device having a touch sensor, characterized in that the supply repeatedly. The method of claim 3, wherein
The pulse width of the high level of the touch sensor driving pulse is increased in proportion to the distance between the crossing portion and the touch sensor driving circuit;
And a low level pulse width of the touch sensor driving pulse increases in proportion to a distance between the crossing portion and the touch sensor readout circuit. The method of claim 3, wherein
The touch sensor read circuit,
And a touch sensor sequentially sampling a plurality of touch sensors positioned in the channel combinations. The method of claim 2,
The touch sensor driving circuit,
And a touch sensor driving pulse, wherein the period of the touch sensor driving pulse is different for each driving channel in response to a time constant being changed according to a sensing position at which the mutual capacitor is formed. The method according to claim 6,
The pulse width of the high level of the touch sensor drive pulse is the same in the drive channels;
And a low level pulse width of the touch sensor driving pulse increases in proportion to a distance between the crossing portion and the touch sensor readout circuit. The method according to claim 6,
The touch sensor read circuit,
A display device having a touch sensor, characterized in that for sampling a plurality of touch sensors present on the same drive channel at the same time.

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