KR20160078751A - Display Device Having a Touch Sensor and Driving Method thereof - Google Patents

Abstract

The objective of the present invention is to improve a signal-to-noise ratio (SNR) by avoiding screen abnormality or touch sensing error due to touch noises. The present invention provides an organic electroluminescence display device with a touch sensor, including a display panel, a touch screen, a touch screen control unit and a timing control unit. The display panel displays an image, and the touch screen is placed in the inside or the outside of the display panel. The touch screen control unit senses touch data through the touch screen. To perform a sensing operation with respect to the touch screen by corresponding to a section to delete the data signal supplied to the display panel, the timing control unit supplies a touch sync signal to the touch screen control unit.

Description

TECHNICAL FIELD [0001] The present invention relates to a display device having a touch sensor and a driving method thereof.

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

As the information technology is developed, the market of display devices, which is a connection medium between users and information, is getting larger. Accordingly, the use of display devices such as an organic light emitting display (OLED), a liquid crystal display (LCD), and a plasma display panel (PDP) is increasing.

Some of the above-described display devices, for example, a liquid crystal display device and an organic light emitting display device, include a display panel including a plurality of sub-pixels arranged in a matrix form and a driver for driving the display panel. The driving unit includes a scan driver for supplying a scan signal (or a gate signal) to the display panel, and a data driver for supplying a data signal to the display panel.

2. Description of the Related Art In the case of a liquid crystal display device, an in-cell touch sensor that incorporates a touch sensor (or a touch screen) in a display panel to meet various needs of a user or an on- A touch screen in the form of an on-cell touch sensor is implemented.

In recent years, in-cell and on-cell touch sensor technologies for embedding (or forming) a touch sensor on a display panel have been increasingly applied to a display device such as an organic light emitting display device in addition to a liquid crystal display device. However, when the touch sensor technology proposed in the liquid crystal display device having various structures and driving characteristics is vigorously applied to the display device, it is difficult to avoid a screen abnormality due to the touch noise or an error in the touch sensing operation We need to find ways to improve.

The present invention for solving the above-mentioned problems of the related art is excellent in applicability to apply a touch sensor to a display device having various structures and driving characteristics, and is applicable to a touch sensor, Thereby improving the signal-to-noise ratio (SNR).

According to an aspect of the present invention, there is provided a display device having a touch sensor including a display panel, a touch screen, a touch screen control unit, and a timing control unit. The display panel displays the image. The touch screen is located inside or outside the display panel. The touch screen control unit senses the touch data through the touch screen. The timing control unit supplies a touch synchronous signal to the touch screen control unit so that a sensing operation for the touch screen is performed corresponding to a period in which the data signal supplied to the display panel is deleted.

The display panel displays an image based on the data signal arranged in units of subframes from the data driver controlled by the timing controller, and the timing controller can generate the touch synchronous signal corresponding to the erasure interval of the subframe.

The erase interval may be included in all bits of the subframe or may be included in the lower bits of the subframe.

The touch screen control unit may sense N (N is the number corresponding to the erasure interval) times of the touch screen for one frame.

The touch screen control unit may sense T (T corresponds to the sum of the start interval of the first deletion interval to the end interval of the last deletion interval) for the touch screen for one frame.

The timing control unit includes a subframe control signal generation unit for generating a subframe synchronization signal for arranging the data signal in units of subframes and a deletion signal for deleting the data signal, And a touch control unit for generating a touch synchronous signal.

In another aspect, the present invention provides a method of driving an organic light emitting display having a touch sensor. A method of driving a display device having a touch sensor includes: supplying a scan signal and a data signal to a display panel during a display driving period and displaying an image; And sensing the touch data by supplying a driving signal to the touch screen during a touch screen driving period, wherein the sensing operation of the touch screen corresponds to a period in which the data signal supplied to the display panel is deleted, .

The touch screen driving section may be separated from the display driving section or coexist within the display driving section.

The touch screen driving section can sense N (N is a number corresponding to the erasure interval) times of the touch screen during one frame.

The touch screen driving section can continuously sense T for the touch screen during one frame (T corresponds to the sum from the start section of the first erasure section to the end section of the last erasure section).

The present invention has an effect of avoiding a screen abnormality due to a touch noise or an error of a touch sensing operation when a display device having an in-cell or an on-cell touch sensor is implemented. In addition, the present invention has an effect of preventing a problem that may occur when a touch sensor is applied to a display device having various structures and driving characteristics. Further, the present invention has an effect of improving a signal-to-noise ratio (SNR) by performing touch sensing by distinguishing from a section for displaying an image.

1 is a block diagram schematically showing a configuration of an organic light emitting display device having a touch sensor according to a first embodiment of the present invention.
FIG. 2 is an exemplary diagram schematically showing a configuration of a touch screen implemented by a mutual touch sensing method; FIG.
3 is an exemplary view showing a configuration of a touch screen implemented by a self-touch sensing method.
4 is an exemplary diagram showing a circuit configuration of a sub-pixel operating in a digital driving manner;
5 is a waveform diagram for helping understanding of the digital driving method.
6 is a waveform diagram showing a driving method of an organic light emitting display device having a touch sensor according to a first embodiment of the present invention.
FIG. 7 is an exemplary diagram showing a method of transmitting a touch report in FIG. 6; FIG.
FIG. 8 is a block diagram showing a main configuration of a timing control unit according to the first embodiment of the present invention; FIG.
FIG. 9 is a waveform diagram showing a driving method of an organic light emitting display device having a touch sensor according to a second embodiment of the present invention; FIG.
Fig. 10 is an exemplary diagram showing a method of transmitting a touch report in Fig. 9; Fig.
11 is a waveform diagram showing a driving method of an organic light emitting display device having a touch sensor according to a third embodiment of the present invention.
FIG. 12 is an exemplary diagram showing a touch report transmission method in FIG. 11; FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

A display device having a touch sensor according to the present invention is implemented as a television, a set-top box, a navigation device, a video player, a Blu-ray player, a personal computer (PC), a home theater and a mobile phone. The display panel of the display device may be a liquid crystal display panel, an organic light emitting display panel, an electrophoretic display panel, a plasma display panel, or the like, but is not limited thereto.

A display device having a touch sensor according to the present invention can be realized by an analog driving method of supplying current or voltage to a display panel or a digital driving method of controlling a light emitting period.

The digital driving method includes an ADS (Address Display Separation) driving method in which an addressing period for supplying a data signal and a light emitting period for emitting light are separated, and an AWD (Address While Display) driving method in which a light emitting period occurs during an addressing period.

As mentioned above, the display panel can be applied not only to a digital driving method, but also to a method requiring a deletion (reset or initialization) operation to erase (remove) a previously stored data signal or a current or voltage driving method. In the following description, a digital driving type organic light emitting display will be described as an example for convenience of explanation.

≪ Embodiment 1 >

FIG. 1 is a block diagram schematically showing the configuration of an organic light emitting display device having a touch sensor according to a first embodiment of the present invention. FIG. 2 is a block diagram schematically illustrating a structure of a touch screen implemented by a mutual touch sensing method. FIG. 3 is an exemplary diagram illustrating a configuration of a touch screen implemented by a self-touch sensing method.

1 to 3, an organic light emitting display having a touch sensor includes an image supply unit 110, a timing control unit 120, a data driving unit 130, a scan driving unit 140, a display panel (PNL) A touch screen TPNL, a touch screen control unit 160, and a power supply unit 180.

The image supply unit 110 processes the data signal DATA and outputs it together with a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, and a clock signal. The image supply unit 110 supplies a data enable signal DE and a data signal DATA via a low voltage differential signaling (LVDS) interface or a TMDS (Transition Minimized Differential Signaling) And supplies a signal, a clock signal, and the like to the timing controller 120.

The timing controller 120 receives a data signal DATA and a data enable signal DE from the image supply unit 110 and receives a gate timing control signal GDC for controlling the operation timing of the scan driver 140 And outputs a data timing control signal DDC for controlling the operation timing of the data driver 130.

The timing controller 120 outputs a data signal DATA together with a gate timing control signal GDC and a data timing control signal DDC through an EPI interface and the like to control operations of the scan driver 140 and the data driver 130 Timing.

The data driver 130 samples and latches the data signal DATA in response to the data timing control signal DDC supplied from the timing controller 120 and converts the digital signal into an analog signal corresponding to the gamma reference voltage and outputs the analog signal .

The data driver 130 supplies the data signal DATA to the sub-pixels SP included in the display panel PNL through the data lines DL1 to DLn. The data driver 130 is formed in the form of an integrated circuit (IC).

The scan driver 140 outputs a scan signal while shifting the level of the gate voltage in response to the gate timing control signal GDC supplied from the timing controller 120. The scan driver 140 includes a level shifter and a shift register.

The scan driver 140 supplies the scan signals to the sub-pixels SP included in the display panel PNL through the scan lines GL1 to GLm. The scan driver 140 is formed in the form of an integrated circuit (IC) or a gate-in-panel type display panel PNL. The portion formed by the gate-in-panel method in the scan driver 140 is a shift register.

The display panel PNL displays an image corresponding to the scan signal supplied from the scan driver 140 and the data signal DATA supplied from the data driver 130. The display panel (PNL) includes sub pixels (SP) that emit light to display an image. The display panel PNL may be implemented as a top emission type, a bottom emission type, or a dual emission type.

The touch screen TPNL is implemented such that an in-cell touch sensor is built in the display panel PNL. The touch sensor of the touch screen (TPNL) is implemented in the form of an electrode capable of extracting a change depending on the presence or absence of a user. Although the touch screen TPNL may be implemented in various forms, the following description will be made by way of example on the basis of mutual capacitance and self capacitance for convenience of explanation.

The touch screen control unit 160 senses the presence or absence of a touch using the touch screen TPNL. The touch screen control unit 160 senses a difference in capacitance that varies depending on whether or not the user touches the touch sensor of the touch screen TPNL. The touch screen control unit 160 senses the touch sensor of the touch screen TPNL or suspends (or omits) the sensing operation in response to the touch synchronization signal Tsync supplied from the timing control unit 120. [

The touch screen control unit 160 includes a driving circuit for generating a driving signal (voltage) for driving the touch screen TPNL, a sensing circuit for sensing the touch sensor, generating data for detecting presence / absence of touch and coordinate information, And a control circuit unit for transmitting presence / absence of touch and position coordinates based on the sensed touch data.

2, the driving circuit unit 161, the sensing circuit unit 163, and the control circuit unit 165 of the touch screen control unit 160 are separated and formed as shown in FIG. 2, .

The driving circuit unit 161 outputs driving signals necessary for touch sensing through the Tx lines Tx1 to Txn. The sensing circuit unit 163 senses a change in the driving signal through the Rx lines Rx1 to Rxn. The control circuit unit 165 drives the driving circuit unit 161 and the sensing circuit unit 163 in response to the touch synchronous signal Tsync and supplies the touch coordinate data XY to the image processing unit 110 and the timing control unit 120 do.

3, the driving circuit unit, the sensing circuit unit, and the control circuit unit of the touch screen control unit 160 are integrally formed (integrated) in the form of an integrated circuit (IC) . The touch screen controller 160 supplies and senses a driving signal through the sensing lines S1 to Si. However, FIGS. 2 and 3 are merely examples, and the touch screen control unit 160 can be integrated or separated into various forms according to a design method.

The power supply unit 180 generates and outputs a power source PWR such as a first power source voltage ELVDD, a second power source voltage ELVSS, a high potential voltage VCC, and a low potential voltage GND. The power supply PWR output from the power supply unit 180 is supplied separately to the timing controller 120, the scan driver 140, the data driver 120, and the display panel PNL.

Hereinafter, an organic electroluminescent display device having subpixels operating in a digital driving system will be described.

FIG. 4 is an exemplary diagram illustrating a circuit configuration of a sub-pixel that operates in a digital driving method, and FIG. 5 is a waveform diagram for helping an understanding of a digital driving method.

As shown in FIG. 4, the sub-pixel SP operating in the digital driving mode includes a first transistor T1, a second transistor T2, a capacitor Cst, an organic light emitting diode OLED, ETFT).

The first transistor T1 has a first node N1 connected to a gate electrode of the first scan line SL1A and a first electrode connected to the first data line DL1 and connected to a gate electrode of the second transistor T2, The second electrode is connected. The first transistor T1 responds to a scan signal and transmits a data signal to the capacitor Cst.

The second transistor T2 has a gate electrode connected to the second electrode of the first transistor T1 and a first electrode connected to the first power line ELVDD and a second electrode coupled to the anode electrode of the organic light emitting diode OLED. Lt; / RTI > The second transistor T2 serves to drive the organic light emitting diode OLED corresponding to the data voltage stored in the capacitor Cst.

The capacitor Cst is connected at one end to the first node N1 connected to the second electrode of the first transistor T1 and to the gate electrode of the second transistor T2 and to the second electrode of the second transistor T2, And the other end is connected to the second node N2 connected to the anode electrode of the light emitting diode OLED. The capacitor Cst serves to store the data voltage and to transfer the stored data voltage to the second transistor T2.

In the organic light emitting diode OLED, the anode electrode is connected to the second node N2 of the second transistor T2 and the other end of the capacitor Cst are connected to each other, the cathode electrode is connected to the second power supply line ELVSS, do.

The erasing transistor ETFT has a first electrode connected to the second node N2 connected to the gate electrode of the first B scan line SL1B and the second electrode of the second transistor T2 and the other end of the capacitor Cst And the second electrode is connected to the erasing signal line ER to which the erasing signal is supplied. The erasing transistor ETFT serves to erase the previously supplied data signal.

In FIG. 4, the second electrode of the erasing transistor (ETFT) is connected to the erasing signal line (ER). However, this is only an example, and the second electrode of the erasing transistor ETFT may be connected to the first node N1.

In the above description, the first electrode and the second electrode may be defined as a source electrode and a drain electrode of a transistor, and may be defined as a drain electrode and a source electrode, depending on the connection relation and the like. The transistor may be selected as N type or P type.

As shown in FIG. 5, the digital driving method divides one frame into a plurality of subframes SF1 to SF6, and divides the ratio of the emission periods, thereby adjusting the intensity of the current and controlling the gradation. For this purpose, the digital driving method adjusts the intensity of the current by adjusting the subframe to 1 (= ON) and 0 (= OFF) by a combination of binary methods. The subframe may be defined as Nth (N is an integer of 4 or more).

Each subframe represents one bit, and the light emitting period of each subframe is increased or decreased approximately twice. The first subframe SF1 means that the light emitting period is the longest among the six subframes, and the sixth subframe SF6 means that the light emitting period is the shortest among the six subframes.

In the digital driving method, the addressing for the next subframe is performed only when the addressing period for one subframe ends. Therefore, if the addressing period for one sub-frame is longer than the light emitting period of the corresponding sub-frame, a deletion interval in which the data signal can be deleted (or removed) so as to hold the time until the addressing of the next sub- need. That is, when the digital driving method expresses 8 bits or more within a limited time of one frame (1 frame), a deletion interval becomes a necessary requirement.

1) Increase the addressing speed (increase the scanning speed), 2) Change the frame frequency (20Hz -> 60Hz -> 30Hz), and so on. However, the method 1) has many constraints such as specification change of the scan driver and structural change of the display panel (one horizontal time reduction). And 2) the method has few constraints but the image quality is degraded.

For this reason, the erase interval is an indispensable method to be adopted in the digital driving method, and it can also be said to be a spontaneous period in terms of the driving method. However, if the use of the erase interval is increased, the expressiveness of the bit is improved, but the black monster interval is increased, so this should be considered.

2. Description of the Related Art Recently, an organic electroluminescent display device has been increasingly applied to an in-line touch sensor that incorporates a touch sensor in a display panel and an on-cell touch sensor technology that forms a touch sensor outside a display panel, in addition to a liquid crystal display device. The insole or on-cell touch sensor type is vulnerable to coupling or noise related to the driving signal of the display panel because the touch sensor is located on the display panel.

Therefore, in order to reduce mutual influence due to coupling between sub pixels and touch sensors, a liquid crystal display device having an in-cell or an on-cell touch sensor has a period (also called a "display driving period & Time division of the section driving the sensors (also referred to as "touch screen driving section").

On the other hand, when the inelic touch sensor technology proposed in the liquid crystal display device having various structures and driving characteristics is vaguely applied, the organic light emitting display device avoids a screen abnormality due to the touch noise or an error of the touch sensing operation It is difficult to find ways to improve or replace it.

Hereinafter, the description of the present invention will be described as an example in which the organic light emitting display device having a touch sensor is implemented by a digital driving method.

FIG. 6 is a waveform diagram showing a driving method of an organic light emitting display having a touch sensor according to the first embodiment of the present invention. FIG. 7 is a view illustrating an example of a method of transmitting a touch report in FIG. FIG. 8 is a block diagram showing a main configuration of a timing control unit according to the first embodiment of the present invention; FIG.

As shown in FIG. 6, the first embodiment of the present invention is divided into a plurality of subframes SF1 to SF6 in a typical form used in the digital driving method. The plurality of subframes SF1 to SF6 includes an addressing period, a light emitting period, and a erasing period. However, the erase interval exists only in the subframes belonging to the group having the shortest light emission period, such as the fourth to sixth subframes SF4 to SF6.

The first embodiment of the present invention performs split touch sensing corresponding to the fourth to sixth subframes SF4 to SF6 having a deletion interval. For example, the first touch sensing is performed corresponding to the erase interval of the fourth sub-frame SF4, the first touch sensing is performed corresponding to the erase interval of the fifth sub-frame SF5, And performs a third touch sensing corresponding to the deletion section.

In the first to sixth sub-frames SF1 to SF6, the addressing period and the light emitting period correspond to the time required for displaying an image, and therefore these intervals are defined as a display driving period (DSP) for driving sub-pixels. In the fourth to sixth sub-frames SF4 to SF6, the deletion interval is defined as a touch screen driving interval TSP for driving the touch sensors.

As mentioned above, the emission periods of the fourth to sixth sub-frames SF4 to SF6 are shorter in the fourth sub-frame SF4 to the sixth sub-frame SF6. However, the erase interval is increased from the fourth subframe SF4 to the sixth subframe SF6. Therefore, the first to third touch periods T1 to T3 included in the touch screen driving period TSP are formed to be longer from the fourth subframe SF4 to the sixth subframe SF6.

In the meantime, since the subframe is divided into six subframes in the first embodiment of the present invention, only the erase interval included in the fourth to sixth subframes SF4 to SF6, which is half of the subframe, is defined as the touch screen driving period. Therefore, when the number of subframes is increased or decreased, the erase interval may be correspondingly changed.

7, the touch data is sensed during the first to third touch periods T1 to T3 corresponding to the deletion intervals included in the fourth to sixth sub-frames SF4 to SF6, And transmit it to the touch report. However, the bar touch report, which is divided into the first to third touch periods T1 to T3, may be transmitted as follows.

As shown in FIG. 7 (a), the touch report TRD1 may be transmitted in synchronization with the third touch period T3 in which the touch data is finally sensed, or may be transmitted thereafter.

As shown in FIG. 7 (b), the touch reports TRD1 to TRD3 may be transmitted synchronously or every time after touch data is sensed. For example, the first touch report TRD1 is transmitted in synchronism with or after the first touch interval T1, the second touch report TRD2 is transmitted in synchronization with the second touch interval T2, or thereafter And the third touch report TRD3 may be transmitted in synchronization with the third touch period T3 or thereafter. However, this is only one example, and the method of transmitting the touch report can be changed into various forms corresponding to the change of the touch sensing method, the touch algorithm, and the like.

As described above, in order to drive the display driving section DSP and the touch screen driving section TSP coexist within one frame, it is required to interlock the timing controller and the touch screen controller. To this end, the timing control unit may be configured as follows.

8, the timing controller 120 includes a clock generator 121, an LVDS interface 122, an internal signal generator 123, a source transmitter 124, a power control signal generator 125, A scan control unit 126, a sub-frame control signal generation unit 127, and a touch control unit 128. 8 shows a part of a block related to the digital driving of the timing control unit 120 in order to explain a configuration related to the present invention.

The clock generating unit 121 generates an internal clock signal in response to the clock signal supplied from the image supply unit. The internal clock signal generated from the clock generator 121 is supplied to the internal signal generator 123, the source transmitter 124, the power supply control signal generator 125, the scan controller 126 and the subframe control signal generator 127 ). ≪ / RTI >

The LVDS interface unit 122 serves to receive various signals such as a data signal output from the image supply unit. The LVDS interface unit 122 is used for data transmission (or communication) between the image supply unit and the timing control unit 120, which can be selected by a different interface scheme.

The internal signal generating unit 123 generates an internal vertical synchronizing signal, a horizontal synchronizing signal, and a data enable signal based on a data enable signal or the like transmitted from the LVDS interface unit 122. The internal signal generating unit 123 transmits the generated internal vertical synchronizing signal, horizontal synchronizing signal, and data enable signal to the sub frame control signal generating unit 127.

The sub-frame control signal generating unit 127 generates a sub-frame control signal for arranging the data signals on a sub-frame basis based on the internal vertical synchronizing signal, the horizontal synchronizing signal, and the data enable signal transmitted from the internal signal generating unit 123, A deletion signal for deleting the signal and the data signal, and the like. The subframe control signal generator 127 transmits a delete signal or the like to the touch controller 128. The sub-frame control signal generator 127 converts an internal vertical synchronous signal, a horizontal synchronous signal, and a data enable signal in accordance with a sub-frame system. The sub-frame control signal generator 127 transmits various control signals generated based on the converted signals and the synchronization signal to the source transmitter 124.

The source transmission unit 124 aligns or rearranges the data signal transmitted from the LVDS interface unit 122 according to the subframe scheme, and outputs the data signal. The source transmission unit 124 receives the clock signal transmitted from the clock generation unit 121, the data signal transmitted from the LVDS interface unit 122, the internal vertical synchronization signal transmitted from the subframe control signal generation unit 127, And a data enable signal or the like to align or rearrange the data signal according to the subframe scheme. The data signal and the like outputted from the source transmission unit 124 are supplied to the data driver 130.

The power control signal generating unit 125 generates a signal for controlling the power supply unit 180 and the scan control unit 126. The power supply control signal generator 125 may generate a signal for controlling the power supply unit 180 and the scan controller 126 based on the clock signal transmitted from the clock generator 121.

The scan controller 126 outputs various signals for controlling the scan driver 140. The scan controller 126 outputs various signals for controlling the scan driver 140 on the basis of the clock signal transmitted from the clock generator 121 and the control signal transmitted from the subframe control signal generator 127.

The touch controller 128 generates a touch sync signal Tsync that can drive the touch screen in response to the delete signal, and controls the touch screen controller based on the generated touch sync signal Tsync. The touch controller 128 may generate a touch sync signal Tsync based on the erasure signal or the like transmitted from the subframe control signal generator 127. [

As described above, the timing controller 120 provides the touch sync signal Tsync in response to the erase interval of the sub-frame, so that the touch-screen control unit is controlled in the form that the display drive period and the touch- .

The organic electroluminescent display device is different from the liquid crystal display device in driving characteristics and structure, and can realize the in-cell touch sensor technology even if the display driving period and the touch screen driving period are not time-divided.

However, if a touch screen is driven during an addressing period or a light emitting period for supplying a data signal, there is a possibility that a signal abnormality due to coupling of a signal, touch noise, or a touch sensing operation may be caused.

Accordingly, the present invention drives the touch screen during the deletion interval irrespective of the interval in which the image is substantially displayed in order to avoid a screen error due to coupling of a signal, a touch noise, or an error of a touch sensing operation .

The addressing period or the light emitting period can be regarded as a display driving period since it relates to an operation of displaying an image. On the other hand, the erase interval relates to the erase operation, not the image display, and also drives the touch screen, so that it can be viewed as the touch screen drive section. Therefore, the display driving period and the touch screen driving period coexist but can be defined as being distinguished from each other.

On the other hand, a deletion interval existing only in a subframe belonging to a group having a short light emission period, such as the fourth to sixth subframes SF4 to SF6, may be a bar image (classification of a moving image or a still image, ), The touch screen can be driven as follows.

Hereinafter, only the parts that are changed according to the first embodiment will be described, and the details of the device, the method, and the like constituting the same will be omitted in order to avoid duplication of description, and will be described with reference to FIGS.

≪ Embodiment 2 >

FIG. 9 is a waveform diagram showing a driving method of an organic light emitting display having a touch sensor according to a second embodiment of the present invention, and FIG. 10 is an exemplary view showing a method of transmitting a touch report in FIG.

As shown in FIG. 9, the second embodiment of the present invention is divided into a plurality of subframes SF1 to SF6 in a typical form used in the digital driving method. The plurality of subframes SF1 to SF6 includes an addressing period, a light emitting period, and a erasing period. However, the erase interval exists only in the subframes belonging to the group having the shortest light emission period, such as the fourth to sixth subframes SF4 to SF6.

The second embodiment of the present invention performs touch sensing during the fourth to sixth sub-frames SF4 to SF6 having the erase interval. For example, touch sensing is performed corresponding to a period (or time) during which the erase interval of the sixth sub-frame SF6 ends, from the erase interval of the fourth sub-frame SF4.

In the first to sixth sub-frames SF1 to SF6, the addressing period and the light emitting period correspond to the time required for displaying an image, and therefore these intervals are defined as a display driving period (DSP) for driving sub-pixels. In the fourth to sixth sub-frames SF4 to SF6, the addressing period and the light emitting period are defined as the display driving period DSP and the erasing period is defined as the touch screen driving period TSP for driving the touch sensors. That is, in the lower subframe (or the lower bit of the subframe), the display driving period (DSP) and the touch screen driving period (TSP) coexist, and the period from the start of the first erase interval to the end of the last erase interval It can be defined as overlapping some portions over a period.

As described above, when the display driving section DSP and the touch screen driving section TSP coexist in the lower sub-frame, the touch sensing operation can be performed at a point where the deterioration of the image quality is minimized. It is possible to secure a sufficient time for the operation.

With this logic, the deletion interval may be varied to secure time for touch sensing. In addition, the V blank time required for the touch sensing may include, for example, a back porch, a front porch, and a width.

As shown in FIGS. 9 and 10, the touch data is sensed during the period from the start of the erase interval of the fourth subframe SF4 to the end of the erase interval of the sixth subframe SF6, and the algorithm is processed Must be sent to touch report.

Since the touch screen driving period TSP continues from the period from the start of the erase interval of the fourth subframe SF4 to the end of the erase interval of the sixth subframe SF6, May be transmitted in synchronization with or transmitted after a period in which the deletion interval of the < RTI ID = 0.0 > However, this is only one example, and the method of transmitting the touch report can be changed into various forms corresponding to the change of the touch sensing method, the touch algorithm, and the like.

≪ Third Embodiment >

FIG. 11 is a waveform diagram illustrating a driving method of an organic light emitting display having a touch sensor according to a third embodiment of the present invention, and FIG. 12 is an exemplary view illustrating a method of transmitting a touch report in FIG.

As shown in FIG. 6, the third embodiment of the present invention is divided into a plurality of subframes (SF1 to SF5) in a typical form used in the digital driving method. The plurality of subframes SF1 to SF5 includes an addressing period, a light emitting period, and a erasing period.

The third embodiment of the present invention performs touch sensing corresponding to the first to fifth subframes SF1 to SF5 having a deletion interval. For example, the first touch sensing T1 is performed corresponding to the deletion interval of the first sub-frame SF1, the second touch sensing T2 is performed corresponding to the deletion interval of the second sub-frame SF2, The fourth touch sensing T4 is performed corresponding to the deletion interval of the fourth subframe SF4 and the fifth touch sensing T5 is performed corresponding to the deletion interval of the fifth subframe SF5 .

In the first to fifth sub-frames SF1 to SF5, the addressing period and the light emitting period correspond to a time required for displaying an image, and therefore these intervals are defined as a display driving period (DSP) for driving sub-pixels. In the first to fifth sub-frames SF1 to SF5, the erase interval is defined as a touch screen driving interval TSP for driving the touch sensors.

In the third embodiment, unlike the first and second embodiments, the first to fifth sub-frames SF1 to SF5 include the addressing period, the light emitting period, and the erase period. When the erase interval is included in all subframes as described above, it is possible to improve and prevent an error that varies the voltage that determines the actual brightness of the subpixel with respect to the current subframe according to the state of the subpixel (turn on or turn off) can do.

As can be seen from the third embodiment, the present invention can perform touch sensing in correspondence with a deletion interval or a section in which an image is not displayed similarly (or a section for supplying or emitting a data signal and a section not related to driving) have.

12, the touch data is sensed during the first to fifth touch periods T1 to T5 corresponding to the deletion intervals included in the first to fifth sub-frames SF1 to SF5, And transmit it to the touch report. Meanwhile, the bar touch report divided into the first to fifth touch periods T1 to T5 may be transmitted as follows.

As shown in FIG. 12A, the touch report TRD may be transmitted in synchronization with the fifth touch period T3 in which the touch data was last sensed, or may be transmitted thereafter.

As shown in (b) of FIG. 12, the touch reports TRD1 to TRD5 may be transmitted synchronously or every time after touch data is sensed. For example, the first touch report TRD1 is transmitted in synchronism with or after the first touch interval T1, the second touch report TRD2 is transmitted in synchronization with the second touch interval T2, or thereafter And the fifth touch report TRD5 may be transmitted in synchronization with the fifth touch interval T5 or thereafter. However, this is only one example, and the method of transmitting the touch report can be changed into various forms corresponding to the change of the touch sensing method, the touch algorithm, and the like.

As can be seen from all the embodiments above, the touch screen control unit senses N (N is the number corresponding to the deletion interval) times of division with respect to the touch screen during one frame or T (T is the time from the beginning of the first deletion interval to the last deletion The time corresponding to the sum up to the end interval of the interval).

As described above, the present invention has an effect of avoiding a screen abnormality due to a touch noise or an error of a touch sensing operation when a display device having an in-cell or an on-cell touch sensor is implemented. In addition, the present invention has an effect of preventing a problem that may occur when a touch sensor is applied to a display device having various structures and driving characteristics. Further, the present invention has an effect of improving a signal-to-noise ratio (SNR) by performing touch sensing by distinguishing from a section for displaying an image.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. In addition, the scope of the present invention is indicated by the following claims rather than the detailed description. Also, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

110: image supply unit 120: timing control unit
130: Data driver 140:
PNL: Display panel TPNL: Touch screen
160: Touch screen control unit 180: Power supply unit
128: Touch controller 127: Sub-frame control signal generator
DSPL: Display driving section TSP: Touch screen driving section

Claims (10)

Display panel;
A touch screen located inside or outside the display panel;
A touch screen controller for sensing touch data through the touch screen; And
And a timing controller for supplying a touch synchronous signal to the touch screen controller so that a sensing operation for the touch screen is performed corresponding to a section for deleting the data signal supplied to the display panel. The method according to claim 1,
The display panel
An image is displayed on the basis of a data signal arranged in units of subframes from a data driver controlled by the timing controller,
Wherein the timing control unit generates the touch synchronizing signal in response to the erasing period of the sub-frame. 3. The method of claim 2,
The deletion interval
Wherein the bit is included in all bits of the sub-frame or is included in the lower bits of the sub-frame. 3. The method of claim 2,
The touch screen control unit
(N is a number corresponding to the erasure interval) times for one frame of the touch screen. 3. The method of claim 2,
The touch screen control unit
Wherein the touch sensor continuously senses the touch screen for a time T (T is a time corresponding to a sum from a start interval of a first erasure interval to an end interval of a last erasure interval) for one frame. The method according to claim 1,
The timing control unit
A subframe control signal generator for generating a subframe synchronization signal for arranging the data signal in subframe units and a deletion signal for deleting the data signal,
And a touch controller for generating the touch synchronizing signal based on the erase signal transmitted from the sub-frame control signal generator. Supplying a scan signal and a data signal to a display panel during a display driving period and displaying an image; And
Supplying a driving signal to the touch screen and sensing touch data during a touch screen driving period,
The touch screen driving section
Wherein the sensing operation of the touch screen is performed corresponding to a period in which the data signal supplied to the display panel is deleted. 8. The method of claim 7,
The touch screen driving section
Wherein the display driving section is separated from the display driving section or coexist within the display driving section. 8. The method of claim 7,
The touch screen driving section
Wherein the touch sensor is divided into N (N is a number corresponding to the erasure interval) times for the touch screen during one frame. 8. The method of claim 7,
The touch screen driving section
(T is a time corresponding to the sum from the start period of the first erasure interval to the end interval of the last erasure interval) for one frame of the touch screen. Way.

Images