Touch display device and driving method thereof

Abstract

A touch display device and a driving method thereof are disclosed. The present invention provides a touch display device, comprising: a display panel including sub-pixels; a touch sensor including touch electrodes formed based on electrodes of light-emitting diodes included in the sub-pixels; and a touch driver configured to sense the touch sensor, wherein the electrodes of the light-emitting diodes are used as touch electrodes during a cut-off period of a light-emitting control transistor for controlling light emission of the light-emitting diodes.

Description

Technical Field

[0001] The invention relates to a touch display device and a driving method thereof. Background Art

[0002] As information technology develops, the market for display devices used as a connecting medium between users and information is growing. Therefore, display devices such as light emitting displays (LEDs), quantum dot displays (QDDs), and liquid crystal displays (LCDs) are increasingly being used.

[0003] The above-mentioned display device includes: a display panel including sub-pixels; a driver outputting a driving signal for driving the display panel; and a power supply generating power to be supplied to the display panel and the driver.

[0004] When a driving signal (e.g., a scan signal and a data signal) is supplied to a sub-pixel formed in the display panel, the display device as described above can display an image through the selected sub-pixel by transmitting light or directly emitting light. In addition, the display device as described above can receive a user input in the form of a touch based on the touch sensor and execute a command corresponding to the touch input. Summary of the invention

[0005] Accordingly, the present invention is directed to a touch display device and a driving method thereof that substantially obviate one or more problems due to limitations and disadvantages of the related art.

[0006] An object of the present invention is to reduce the thickness of a touch display device, simplify the manufacturing process of a display panel with a touch sensor, and reduce the manufacturing cost of a display panel by implementing a touch sensor based on an anode and a cathode included in a light emitting diode.

[0007] In one aspect, the present invention may provide a touch display device comprising: a display panel comprising sub-pixels; a touch sensor comprising touch electrodes formed based on electrodes of light-emitting diodes included in the sub-pixels; and a touch driver configured to sense the touch sensor, wherein the electrodes of the light-emitting diodes are used as touch electrodes during a cut-off period of a light-emitting control transistor for controlling the light-emitting diodes.

[0008] The electrode of a light emitting diode can be an anode or a cathode.

[0009] The cathode of the light emitting diode may be connected to a low voltage power line during a display operation period for displaying an image on the display panel.

[0010] The cathode of the light emitting diode may be electrically suspended during a touch operation period for touch sensing of the touch sensor or may be electrically connected to a touch driver.

[0011] The touch display device may further include a first control transistor, which is disposed between the second electrode of the light emitting control transistor and the anode of the light emitting diode, and the first control transistor may be turned on during a display operation period for displaying an image on the display panel.

[0012] The touch display device may further include a second control transistor, which is disposed between an anode of the light emitting diode and a sensing channel of the touch driver, and the second control transistor may be turned on in a touch operation period for touch sensing of the touch sensor.

[0013] Each of the first control transistor and the second control transistor may be configured as an n-type transistor or a p-type transistor.

[0014] The touch driver can perform a sensing operation through the electrode of the light emitting diode during the off period of the light emitting control transistor.

[0015] The touch display device may further include: a selector configured to connect the cathode of the light emitting diode to a low voltage power line during the display operation period to display an image on the display panel, and to electrically suspend the cathode of the light emitting diode during the touch operation period for touch sensing of the touch sensor; a first control transistor disposed between the second electrode of the light emitting control transistor and the anode of the light emitting diode, and turned on during the display operation period; and a second control transistor disposed between the anode of the light emitting diode and the sensing channel of the touch driver, and turned on during the touch operation period. The electrode of the light emitting diode may be an anode.

[0016] The touch display device may also include a selector and a first control transistor, wherein the selector is configured to connect the cathode of the light-emitting diode to a low-voltage power line during a display operation period for displaying an image on the display panel, and to electrically connect the cathode of the light-emitting diode to a touch driver during a touch operation period for touch sensing of the touch sensor, and the first control transistor is arranged between the second electrode of the light-emitting control transistor and the anode of the light-emitting diode, and is turned on during the display operation period, wherein the electrode of the light-emitting diode may be a cathode.

[0017] The touch display device may also include a first control transistor arranged between the second electrode of the light emitting control transistor and the anode of the light emitting diode and turned on during the display working period, and a second control transistor arranged between the cathode of the light emitting diode and the sensing channel of the touch driver and turned on during the touch working period, wherein the electrode of the light emitting diode may be a cathode.

[0018] In another aspect, the present invention may provide a method for driving a touch display device, the touch display device comprising: a display panel including sub-pixels; a touch sensor including a touch electrode formed based on an electrode of a light-emitting diode included in the sub-pixel; and a touch driver configured to sense the touch sensor. The method for driving a touch display device may include the following steps: causing the sub-pixel to emit light during a display operation period for displaying an image on the display panel; and sensing one of the electrodes of the light-emitting diode during a touch operation period for touch sensing of the touch sensor, wherein the electrode of the light-emitting diode is used as a touch electrode during a cut-off period of a light-emitting control transistor for controlling light emission of the light-emitting diode.

[0019] The step of sensing one of the electrodes of the light-emitting diode may include the following steps: electrically suspending the cathode of the light-emitting diode during a touch working period, turning off a first control transistor, the first control transistor being arranged between a second electrode of the light-emitting control transistor and an anode of the light-emitting diode, turning on a second control transistor, the second control transistor being arranged between the anode of the light-emitting diode and a sensing channel of a touch driver, and sensing the anode of the light-emitting diode.

[0020] The step of sensing one of the electrodes of the light-emitting diode may include the following steps: electrically connecting the cathode of the light-emitting diode to a touch driver during a touch working period, turning off a first control transistor, which is arranged between a second electrode of the light-emitting control transistor and an anode of the light-emitting diode, and sensing the cathode of the light-emitting diode. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated into and constitute a part of this application. The accompanying drawings illustrate embodiments of the present invention and together with the description serve to explain the principle of the present invention. In the drawings:

[0022] Figure 1 is a block diagram schematically illustrating a light emitting display device;

[0023] Figure 2 It is schematically shown Figure 1 A diagram of the sub-pixels shown;

[0024] Figures 3 to 5 is a diagram for briefly describing a touch display device;

[0025] Figure 6 is a block diagram schematically showing a touch display device according to a first embodiment of the present invention;

[0026] Figure 7 is a diagram for briefly describing a portion of a touch display device according to a first embodiment of the present invention;

[0027] Figure 8 is a diagram for describing a touch operation and a display operation according to a first embodiment of the present invention;

[0028] Fig. 9 is a diagram showing a touch electrode and a touch driver according to a first embodiment of the present invention;

[0029] Fig.10 and Fig.11 is a diagram for briefly describing the structure of a touch electrode;

[0030] Fig.12 is a diagram showing a touch electrode and a touch driver according to a second embodiment of the present invention;

[0031] Fig.13 is a waveform diagram for describing a driving method according to a second embodiment of the present invention;

[0032] Fig.14 and Fig.15 is a diagram showing operations of a touch electrode and a touch driver according to a second embodiment of the present invention;

[0033] Fig.16 is a diagram showing a touch electrode and a touch driver according to a third embodiment of the present invention;

[0034] Fig.17 is a waveform diagram for describing a driving method according to a third embodiment of the present invention;

[0035] Fig.18 is a diagram showing a touch electrode and a touch driver according to a fourth embodiment of the present invention;

[0036] Fig.19 is a waveform diagram for describing a driving method according to a fourth embodiment of the present invention;

[0037] Fig. 20 is a diagram showing a touch electrode and a touch driver according to a fifth embodiment of the present invention;

[0038] Fig.21 and Fig. 22 is a diagram for briefly describing the structure of a touch electrode;

[0039] Fig.23 is a diagram showing a touch electrode and a touch driver according to a sixth embodiment of the present invention;

[0040] Fig.24 is a waveform diagram for describing a driving method according to a sixth embodiment of the present invention;

[0041] Fig.25 and Fig.26 is a diagram showing operations of a touch electrode and a touch driver according to a sixth embodiment of the present invention;

[0042] Fig. 27 is a diagram showing a touch electrode and a touch driver according to a seventh embodiment of the present invention;

[0043] Fig.28 is a waveform diagram for describing a driving method according to a seventh embodiment of the present invention;

[0044] Fig.29 is a diagram showing a touch electrode and a touch driver according to an eighth embodiment of the present invention;

[0045] Fig.30 is a waveform diagram for describing a driving method according to an eighth embodiment of the present invention;

[0046] Fig.31 is a diagram showing a touch electrode and a touch driver according to a ninth embodiment of the present invention; and

[0047] Fig.32 FIG. 1 is a diagram showing a touch electrode and a touch driver according to a tenth embodiment of the present invention. DETAILED DESCRIPTION

[0048] The touch display device according to the present invention can receive a user input in the form of a touch based on a touch sensor and execute a command corresponding to the touch input. The touch display device can be implemented as a television, a video player, a personal computer (PC), a home theater system, an automotive electronic device, a smart phone, etc., but is not limited thereto.

[0049] The touch display device according to the present invention can be implemented as a light emitting display (LED) device, a quantum dot display (QDD) device, a liquid crystal display (LCD) device, etc. However, for ease of description, an LED device based on direct light emission of an inorganic light emitting diode or an organic light emitting diode will be exemplified below.

[0050] In addition, a self-capacitance touch sensor that detects capacitance changes based on a single touch sensor or a mutual capacitance touch sensor that detects capacitance changes based on two touch electrodes may be used as the touch sensor. However, for ease of description, a self-capacitance touch sensor will be exemplified.

[0051] Figure 1 is a block diagram schematically showing a light emitting display device, Figure 2 It is schematically shown Figure 1 A diagram of the sub-pixels shown.

[0052] like Figure 1 and Figure 2As shown, the light emitting display device may include an image provider 110 , a timing controller 120 , a scan driver 130 , a data driver 140 , a display panel 150 , and a power supply 180 .

[0053] The image provider 110 (or the host system) may output various driving signals together with an image data signal provided from the outside or an image data signal stored in an internal memory. The image provider 110 may provide the timing controller 120 with a data signal and various driving signals.

[0054] The timing controller 120 may output a gate timing control signal GDC for controlling the operation timing of the scan driver 130, a data timing control signal DDC for controlling the operation timing of the data driver 140, and various synchronization signals (a vertical synchronization signal Vsync and a horizontal synchronization signal Hsync). The timing controller 120 may provide the data signal DATA provided from the image provider 110 together with the data timing control signal DDC to the data driver 140. The timing controller 120 may be configured as an integrated circuit (IC) and may be mounted on a printed circuit board, but the present invention is not limited thereto.

[0055] The scan driver 130 may output a scan signal (or a scan voltage) in response to a gate timing control signal GDC provided from the timing controller 120. The scan driver 130 may provide the scan signal to the sub-pixels included in the display panel 150 through the scan lines GL1 to GLm. The scan driver 130 may be configured as an IC, or may be directly formed in a gate of a panel structure on the display panel 150.

[0056] The data driver 140 may sample and latch the data signal DATA in response to the data timing control signal DDC provided from the timing controller 120, convert the data signal in digital form into a data voltage in analog form based on the gamma reference voltage, and output the data voltage. The data driver 140 may provide the data voltage to the sub-pixels included in the display panel 150 through the data lines DL1 to DLn. The data driver 140 may be formed in the form of an IC and mounted on the display panel 150 or on a printed circuit board, but the present invention is not limited thereto.

[0057] The power supply 180 may generate a high-level first power and a low-level second power based on an external input voltage, and output the first power and the second power through a first power line EVDD and a second power line EVSS. The power supply 180 may generate and output a voltage required for the operation of the scan driver 130 (e.g., a gate voltage including a gate high voltage and a gate low voltage) and a voltage required for the operation of the data driver 140 (e.g., a drain voltage including a drain voltage and a half-drain voltage) as well as the first power and the second power.

[0058] The display panel 150 may display an image in response to a drive signal including a scan signal and a data voltage, a first power, and a second power. The sub-pixels of the display panel 150 directly emit light. The display panel 150 may be manufactured based on a rigid or flexible substrate such as a glass substrate, a silicon substrate, or a polyimide substrate. The sub-pixels that emit light may include red, green, and blue pixels or red, green, blue, and white pixels.

[0059] For example, a single sub-pixel SP may be connected to a first data line DL1, a first gate line GL1, a first power line EVDD, and a second power line EVSS. A single sub-pixel SP may have a pixel circuit including a switching transistor, a driving transistor, a capacitor, and an organic light emitting diode. The sub-pixel used in the light emitting display device directly emits light and therefore has a complex circuit configuration. In addition, the sub-pixel includes not only an organic light emitting diode, but also a compensation circuit for compensating for degradation of a driving transistor that provides a driving current to the organic light emitting diode. Therefore, the sub-pixel (SP) is simply shown in the form of a box in the figure.

[0060] Although the timing controller 120 , the scan driver 130 , and the data driver 140 have been described as separate components, one or more of the timing controller 120 , the scan driver 130 , and the data driver 140 may be integrated into a single IC according to a light emitting display device implementation method.

[0061] Figures 3 to 5 is a diagram for briefly describing a touch display device.

[0062] like Figure 3 and Figure 4 As shown, the touch display device may include a display panel (PNL) 150, a touch sensor (TSP) 155, a data driver (DIC) 140, and a touch driver (ROIC) 145 (readout circuit or sensing circuit).

[0063] The touch sensor 155 is an input device that can receive a user input as a touch input and can be provided together with the display panel 150 that displays an image. More specifically, the touch sensor 155 can be formed as an in-box type through a series of processes for manufacturing the display panel 150. That is, a touch electrode of the touch sensor 155 can be formed in the display panel 150 (integrated with the display panel).

[0064] The touch driver 145 can detect the presence or absence of a touch applied to the display panel 150, input position information, etc. by applying a touch driving voltage through a touch electrode included in the touch sensor 155 and then sensing the touch. The touch driver 145 works together with the touch sensor 155 and can sense a finger touch from a user (or a pen touch from a user).

[0065] like Figure 4 and Figure 5 As shown, according to implementation methods of the display panel 150 and the touch sensor 155 , the touch driver (ROIC) 145 may be configured in the form of an IC separate from the data driver 140 , or may be included in the data driver 140 .

[0066] Figure 6 is a block diagram schematically showing a touch display device according to a first embodiment of the present invention, Figure 7 is a diagram for briefly describing a portion of a touch display device according to a first embodiment of the present invention, Figure 8 1 is a diagram for describing a touch operation and a display operation according to a first embodiment of the present invention.

[0067] like Figure 6 As shown, the touch sensor 155 includes a plurality of touch electrodes TE and may be located in the display panel 150. The touch electrodes TE may be formed based on the electrodes included in the sub-pixels SP. The touch electrodes TE may be electrically connected to a touch driver (ROIC) 145 through touch sensing lines SL. One or more touch drivers 145 may be provided according to the size of the touch sensor 155.

[0068] like Figure 7 and Figure 8 As shown, a single sub-pixel SP may be connected to a first power line EVDD, a second power line EVSS, a first data line DL1, and a first gate line GL1. The single sub-pixel SP may include an organic light emitting diode (OLED) for emitting light.

[0069] A single subpixel SP may receive a data voltage for grayscale representation to emit light in a display operation period and receive a black data voltage for touch sensing without emitting light in a touch operation period, but the present invention is not limited thereto. For example, the black data voltage may not be applied according to a driving method.

[0070] The touch driver (ROIC) 145 may include a preamplifier AMP, a feedback capacitor Cfb, and a sensing channel SCH. The non-inverting terminal (+) of the preamplifier AMP may be connected to a line through which a touch drive voltage VIN is transmitted, and its inverting terminal (-) may be connected to the sensing channel SCH. One end of the feedback capacitor Cfb may be connected to the inverting terminal (-) of the preamplifier AMP, and the other end thereof may be connected to the output terminal VOUT of the preamplifier AMP. The touch driver (ROIC) 145 may be connected to the touch sensing line SL through the sensing channel SCH.

[0071] The touch driver (ROIC) 145 can obtain touch sensing values ​​from the touch electrodes TE included in a single sub-pixel SP through a sensing channel SCH, integrate and sample the touch sensing values, generate touch raw data, through which the presence or absence of touch or touch position information can be determined, and output raw touch data.

[0072] After the touch operation period according to the touch electrode TE and the touch driver 145 , there may be a display operation period in which a data voltage is applied to the sub-pixel SP to make the OLED emit light and display an image.

[0073] An example is shown in which the touch operating period and the display operating period are generated once within one frame period. However, according to the touch sensing method and the display driving method, the touch operating period and the display operating period may be alternately generated two or more times.

[0074] Although an example in which a touch operating period and a display operating period are generated at a one-to-one ratio is shown, the generation ratio thereof may depend on a touch sensing method and a display driving method.

[0075] Fig. 9 1 is a diagram showing a touch electrode and a touch driver according to a first embodiment of the present invention, Fig.10 and Fig.11 is a diagram for briefly describing the structure of a touch electrode.

[0076] like Fig. 9 As shown, the touch electrode TE may be formed based on the anode AND of the organic light emitting diode OLED included in the sub-pixel SP. The anode AND of the organic light emitting diode OLED may be used as the touch electrode TE during the off period of the light emission control transistor. The touch sensing line SL may electrically connect the anode AND of the organic light emitting diode OLED to the sensing channel SCH of the touch driver 145.

[0077] When a touch according to a user's finger touch is applied within a touch operating period, the touch driver 145 may obtain a touch sensing value Tsen regarding a change in the feedback capacitor Cfb from the anode AND of the organic light emitting diode OLED.

[0078] like Fig.10 As shown, the first subpixel SP1 and the second subpixel SP2 may have extended anodes EAND1 and EAND2. In the first subpixel SP1, the extended anode EAND1 may be defined as an anode having a wider area than a normal anode so as to function as the first touch electrode TE1.

[0079] In the first subpixel SP1, the extended anode EAND1 may be electrically connected to the electrode of the driving transistor through the first contact hole CH1 like a regular anode. In addition, the extended anode EAND1 may be electrically connected to the sensing channel of the touch driver by connecting to the first sensing line SL1 through the second contact hole CH2.

[0080] Referring to the above description, the sub-pixel of the display panel has an extended anode electrode, and the touch driver can obtain a touch sensing value through a sensing line connected to the extended anode electrode during a touch operation period.

[0081] like Fig.11 As shown in (a), the touch electrode TE may be formed based on the extended anode electrode EAND included in the first sub-pixel SP1. The extended anode electrode EAND may be connected to a single sensing line SL.

[0082] like Fig.11 As shown in (b), the touch electrode TE may be formed based on the first to fourth anodes AND1 to AND4 included in the first to fourth sub-pixels SP1 to SP4. The first to fourth anodes AND1 to AND4 may be connected to a single sensing line SL.

[0083] from Fig.11 It can be determined that a single touch electrode TE may be formed based on the extended anode electrode EAND included in a single sub-pixel or based on the anode electrodes AND1 to AND4 included in a plurality of sub-pixels.

[0084] In the case of a structure in which the first to fourth anodes AND1 to AND4 included in the four sub-pixels SP1 to SP4 are electrically connected, as shown in FIG. Fig.11 As shown in (b), a single touch electrode TE may be formed based on an unextended anode. However, this is only an example, and a single touch electrode TE may also be formed based on Fig.11 The extended anode EAND is formed in the structure shown in (b).

[0085] Therefore, a single touch electrode TE may be formed based on an anode included in a single sub-pixel or an anode included in a plurality of sub-pixels in consideration of touch sensing sensitivity or resolution.

[0086] When a touch sensor is formed based on an anode of an organic light emitting diode OLED included in a sub-pixel as in the first embodiment of the present invention, the thickness of the touch display device can be reduced, and the number of manufacturing processes and manufacturing costs of a display panel with a touch sensor can be reduced.

[0087] Hereinafter, an additional embodiment for implementing a touch sensor based on an anode of an OLED included in a sub-pixel as in the first embodiment of the present invention will be described. Although an example in which a single sub-pixel is composed of seven p-type transistors, a single capacitor, and a single OLED will be described below, the present invention is not limited thereto.

[0088] Fig.12 2 is a diagram showing a touch electrode and a touch driver according to a second embodiment of the present invention, Fig.13 is a waveform diagram for describing a driving method according to a second embodiment of the present invention, Fig.14 and Fig.15 2 is a diagram illustrating operations of a touch electrode and a touch driver according to a second embodiment of the present invention.

[0089] like Fig.12 and Fig.13 As shown, a single sub-pixel may include a first transistor T1, a second transistor T2, a third transistor T3, a fourth transistor T4, a fifth transistor T5, a sixth transistor T6, a capacitor CST, a driving transistor DT, and an organic light emitting diode OLED.

[0090] The first transistor T1 may have a gate connected to the Nth scan line SCAN[n], a first electrode connected to the second electrode of the driving transistor DT, and a second electrode connected to the gate of the driving transistor DT. The first transistor T1 may be used to electrically connect (diode-connect) the gate and the second electrode of the driving transistor DR, and transmit the data voltage transmitted through the second transistor T2 to one end of the capacitor CST in response to the Nth scan signal Scan[n] applied through the Nth scan line SCAN[n].

[0091] The second transistor T2 may have a gate connected to the Nth scan line SCAN[n], a first electrode connected to the first data line DL1, and a second electrode connected to the first electrode of the driving transistor DT and the first electrode of the third transistor T3. The second transistor T2 may be used to output a data voltage transmitted through the first data line DL1 in response to the Nth scan signal Scan[n] applied through the scan line SCAN[n].

[0092] The third transistor T3 may have a gate connected to the Nth light emission control line EM[n], a first electrode connected to the first electrode of the driving transistor DT and the second electrode of the second transistor T2, and a second electrode connected to the other end of the capacitor CST. The third transistor T3 may be used to transmit the first power transmitted through the first power line EVDD to the first electrode of the driving transistor DT in response to the Nth light emission control signal Em[n] applied through the Nth light emission control line EM[n].

[0093] The fourth transistor T4 may have a gate connected to the Nth light emission control line EM[n], a first electrode connected to the second electrode of the driving transistor DT, and a second electrode connected to the anode of the organic light emitting diode OLED and the first electrode of the sixth transistor T6. The fourth transistor T4 may be used to transmit a driving current generated from the driving transistor DT to the anode of the organic light emitting diode OLED in response to the Nth light emission control signal Em[n] applied through the Nth light emission control line EM[n]. That is, the fourth transistor T4 is a light emission control transistor that controls light emission of the organic light emitting diode OLED.

[0094] The fifth transistor T5 may have a gate connected to the (N-1)th scan line SCAN[N-1], a first electrode connected to one end of the capacitor CST and the gate of the driving transistor DT, and a second electrode connected to the initialization voltage line VINI. The fifth transistor T5 may be used to transmit an initialization voltage transmitted through the initialization voltage line VINI to one end of the capacitor CST and the gate of the driving transistor DT in response to the (N-1)th scan signal Scan[n-1] applied through the (N-1)th scan line SCAN[n-1].

[0095] The sixth transistor T6 may have a gate connected to the Nth scan line SCAN[n], a first electrode connected to the second electrode of the fourth transistor T4 and the anode of the organic light emitting diode OLED, and a second electrode connected to the initialization voltage line VINI. The sixth transistor T6 may be configured to transmit an initialization voltage transmitted through the initialization voltage line VINI to the anode of the organic light emitting diode OLED in response to an Nth scan signal Scan[n] applied through the Nth scan line SCAN[n].

[0096] One end of the capacitor CST may be connected to the gate electrode of the driving transistor DT, the second electrode of the first transistor T1, and the second electrode of the fifth transistor T5, and the other end of the capacitor CST may be connected to the first power line EVDD and the second electrode of the third transistor T3. The capacitor CST may be used to store a data voltage and transmit the stored data voltage to the gate electrode of the driving transistor.

[0097] The gate of the driving transistor DT may be connected to one end of the capacitor CST and the second electrode of the first transistor T1, the first electrode of the driving transistor DT may be connected to the second electrode of the second transistor T2 and the first electrode of the third transistor T3, and the second electrode of the driving transistor DT may be connected to the first electrode of the first transistor T1 and the first electrode of the fourth transistor T4. The driving transistor DT may be used to generate a driving current in response to a data voltage stored in the capacitor CST.

[0098] The anode of the organic light emitting diode OLED may be connected to the second electrode of the fourth transistor T4 and the first electrode of the sixth transistor T6, and the cathode of the organic light emitting diode OLED may be connected to the input terminal of the selector SEL. The organic light emitting diode OLED may be used to emit light based on the driving current from the driving transistor DT.

[0099] The selector SEL may be included in the sub-pixel or disposed outside the sub-pixel. The outside of the sub-pixel may represent a non-luminous area included in the display area of ​​the display panel and a non-display area outside the display area. The selector SEL may connect the cathode of the organic light emitting diode OLED to the second power line EVSS, or electrically suspend the cathode of the organic light emitting diode OLED in response to a selection signal Mux applied through the selection signal line MUX.

[0100] The touch driver 145 may include a preamplifier AMP, a feedback capacitor Cfb, and a sensing channel SCH. The touch driver 145 may be electrically connected to an anode electrode of the organic light emitting diode OLED through a touch sensing line SL connected to the sensing channel SCH.

[0101] A single sub-pixel may operate in the initialization period INIT, the sampling period SAM, the holding period HOL, and the light emitting period EMP.

[0102] The fifth transistor T5 may be turned on by the (N-1)th scan signal Scan[n-1] in the initialization period INIT. One end of the capacitor CST and the gate (gate node) of the driving transistor DT may be initialized according to the turned-on fifth transistor T5. The first transistor T1 and the second transistor T2 may be turned on by the Nth scan signal Scan[n] in the sampling period SAM. The operation of sampling the threshold voltage of the driving transistor DT may be performed according to the turned-on first transistor T1 and the second transistor T2. The capacitor CST may store the data voltage whose threshold voltage of the driving transistor DT has been compensated. All transistors may be turned off in the holding period HOL. The holding period HOL is a period (voltage holding period) for stabilizing the sampling operation and data voltage storage operation performed in the sampling period SAM. The holding period HOL may be omitted according to the driving method.

[0103] The third transistor T3 and the fourth transistor T4 may be turned on by the Nth emission control signal Em[n] in the emission period EMP. The driving transistor DT may generate a driving current according to the turned-on third transistor T3 and the fourth transistor T4. In addition, the organic light emitting diode OLED may emit light based on the driving current Ioled.

[0104] like Fig.13 and Fig.14 As shown, the third transistor T3, the driving transistor DT and the fourth transistor T4 can be turned on in the display working period Display. The selector SEL can connect the cathode of the organic light emitting diode OLED to the second power line EVSS in the display working period Display in response to the selection signal Mux. Therefore, the organic light emitting diode OLED can emit light in the display working period Display based on the driving current Ioled transmitted by the turned-on fourth transistor T4.

[0105] like Fig.13 and Fig.15 As shown, the driving transistor DT and the fourth transistor T4 can be turned off in the touch working period Touch. The selector SEL can electrically suspend the cathode of the organic light emitting diode OLED in response to the selection signal Mux in the touch working period. Therefore, the touch driver 145 can obtain the touch sensing value Tsen through the anode of the organic light emitting diode OLED in the touch working period Touch.

[0106] Since the anode of the organic light emitting diode OLED acts as a touch electrode during the touch operation period, as described above, the anode of the organic light emitting diode OLED can receive and sense a user input in the form of a touch.

[0107] The light emission period EMP of the organic light emitting diode OLED may start (light emission on) when the Nth light emission control signal Em[n] changes from a logic high level H to a logic low level L, and may end (light emission off) when it changes from a logic low level L to a logic high level H. Therefore, the touch operation period Touch may correspond to a period in which the Nth light emission control signal Em[n] maintains a logic high level H.

[0108] Thus, an example has been described in which the cathode of the organic light emitting diode OLED is electrically suspended during the period in which the selection signal Mux or the Nth light emitting control signal Em[n] maintains the logic high level H. However, the cathode of the organic light emitting diode OLED may be configured so that it is electrically suspended when the selection signal Mux is at a logic low level instead of a logic high level H. Fig.16 2 is a diagram showing a touch electrode and a touch driver according to a third embodiment of the present invention, Fig.17 3 is a waveform diagram for describing a driving method according to a third embodiment of the present invention. Hereinafter, a third embodiment of the present invention modified from the second embodiment will be described with portions modified from the second embodiment as the example.

[0109] like Fig.16 and Fig.17 As shown, a single sub-pixel may further include a first n-type control transistor TR1 and a second n-type control transistor TR2. The first control transistor TR1 may be disposed between the fourth transistor T4 and the anode of the organic light emitting diode OLED. The second control transistor TR2 may be disposed between the anode of the organic light emitting diode OLED and the sensing channel SCH of the touch driver 145.

[0110] The first control transistor TR1 may have a gate connected to the first node control signal line CS1, a first electrode connected to the second electrode of the fourth transistor T4, and a second electrode connected to the anode of the organic light emitting diode OLED, the first electrode of the sixth transistor T6, and the second electrode of the second control transistor TR2.

[0111] The first control transistor TR1 can be turned on in the display operation period Display and turned off in the touch operation period Touch. To this end, the first node control signal Cs1 sent through the first node control signal line CS1 can be applied at a logic high level H in the display operation period Display and applied at a logic low level L in the touch operation period Touch.

[0112] The second control transistor TR2 may have a gate connected to the second node control signal line CS2, a first electrode connected to the touch sensing line SL, and a second electrode connected to the anode of the organic light emitting diode OLED, the first electrode of the sixth transistor T6, and the second electrode of the first control transistor TR1.

[0113] The second control transistor TR2 can be turned off in the display working period Display, and turned on in the touch working period Touch. To this end, the second node control signal Cs2 sent through the second node control signal line CS2 can be applied at a logic low level L in the display working period Display, and applied at a logic high level H in the touch working period Touch.

[0114] Therefore, the first control transistor TR1 can improve the electrical independence of the anode of the organic light emitting diode OLED used as the touch electrode by being turned off in the touch working period. That is, the first control transistor TR1 and the second control transistor TR2 can improve the working independence of the display device in the working period (display operation and touch operation) in the display working period Display and the touch working period Touch.

[0115] Fig.18 4 is a diagram showing a touch electrode and a touch driver according to a fourth embodiment of the present invention, Fig.19 : is a waveform diagram for describing a driving method according to a fourth embodiment of the present invention. Hereinafter, a fourth embodiment of the present invention modified from the third embodiment will be described focusing on portions modified from the third embodiment.

[0116] like Fig.18 and Fig.19 As shown, a single sub-pixel may further include a first p-type control transistor TR1 and a second n-type control transistor TR2. The first control transistor TR1 may be disposed between the fourth transistor T4 and the anode of the organic light emitting diode OLED. The second control transistor TR2 may be disposed between the anode of the organic light emitting diode OLED and the sensing channel SCH of the touch driver 145.

[0117] The first control transistor TR1 may have a gate connected to the node control signal line CS, a first electrode connected to the second electrode of the fourth transistor T4, and a second electrode connected to the anode of the organic light emitting diode OLED, the first electrode of the sixth transistor T6, and the second electrode of the second control transistor TR2.

[0118] The second control transistor TR2 may have a gate connected to the node control signal line CS, a first electrode connected to the touch sensing line SL, and a second electrode connected to the anode of the organic light emitting diode OLED, the first electrode of the sixth transistor T6, and the second electrode of the first control transistor TR1.

[0119] The first control transistor TR1 may be turned on in the display operation period Display, and turned off in the touch operation period Touch. The second control transistor TR2 may be turned off in the display operation period Display, and turned on in the touch operation period Touch.

[0120] The node control signal Cs transmitted through the node control signal line CS may be applied at a logic low level L in the display operation period Display, and applied at a logic high level H in the touch operation period Touch. Therefore, when the first control transistor TR1 is configured as a p-type transistor and the second control transistor TR2 is configured as an n-type transistor, the two transistors TR1 and TR2 may share a single node control signal line CS, and thus may overcome disadvantages due to an increase in the number of signal lines and design difficulties due to the setting of the signal lines.

[0121] Fig. 20 is a diagram showing a touch electrode and a touch driver according to a fifth embodiment of the present invention, Fig.21 and Fig. 22 is a diagram for briefly describing the structure of a touch electrode.

[0122] like Fig. 20 As shown, the touch electrode TE may be formed based on the cathode CAT of the organic light emitting diode OLED included in the sub-pixel SP. The cathode CAT of the organic light emitting diode OLED may be used as the touch electrode TE during the off period of the light emission control transistor. The touch sensing line SL may electrically connect the cathode CAT of the organic light emitting diode OLED and the sensing channel SCH of the touch driver 145.

[0123] When a touch according to a user's finger is applied within the touch operating period, the touch driver 145 may obtain a touch sensing value Tsen regarding a change in the feedback capacitor Cfb from the cathode CAT of the organic light emitting diode OLED.

[0124] like Fig.21 As shown, the cathode CAT is formed to cover the entire display area AA of the display panel (PNL) 150 having the touch sensor TSP, but the cathode CAT may be separated in the touch electrode TE according to the cathode separation. By being connected to the first sensing line SL1 through the third contact hole CH3, the separated touch electrode TE may be electrically connected to the sensing channel of the touch driver.

[0125] Referring to the above description, the sub-pixels of the display panel have separated cathodes, and the touch driver can obtain touch sensing values ​​through the sensing lines connected to the separated cathodes during a touch operation period.

[0126] like Fig. 22 As shown in (a), the touch electrode TE may be included in the first sub-pixel SP1 and formed based on the cathode CAT separated from other cathodes. The separated cathode CAT may be connected to a single sensing line SL. That is, the touch electrode TE may correspond to the size (area) of the first sub-pixel SP1.

[0127] like Fig. 22 As shown in (b), the touch electrode TE may be included in the first to fourth sub-pixels SP1 to SP4 and formed based on the cathode CAT separated from other cathodes. The separated cathode CAT may be connected to a single sensing line SL. That is, the touch electrode TE may correspond to the size (area) of the first to fourth sub-pixels SP1 to SP4.

[0128] As described above, when a touch sensor is configured based on the cathode of an organic light emitting diode included in a sub-pixel as in the fifth embodiment of the present invention, the thickness of the touch display device can be reduced, and the number of manufacturing processes and manufacturing costs of a display panel with a touch sensor can be reduced.

[0129] Hereinafter, an additional embodiment for implementing a touch sensor based on a cathode of an OLED included in a sub-pixel as in the first embodiment of the present invention will be described. Although an example in which a single sub-pixel is composed of seven p-type transistors, a single capacitor, and a single OLED will be described below, the present invention is not limited thereto.

[0130] Fig.23 is a diagram showing a touch electrode and a touch driver according to a sixth embodiment of the present invention, Fig.24 is a waveform diagram for describing a driving method according to a sixth embodiment of the present invention, Fig.25 and Fig.26 2 is a diagram illustrating operations of a touch electrode and a touch driver according to a sixth embodiment of the present invention.

[0131] like Fig.23 and Fig.24 As shown, a single sub-pixel may include a first transistor T1, a second transistor T2, a third transistor T3, a fourth transistor T4, a fifth transistor T5, a sixth transistor T6, a capacitor CST, a driving transistor DT, a first control transistor TR1 and an organic light emitting diode OLED.

[0132] The first control transistor TR1 may be configured as an n-type transistor different from other transistors. The components and their connection relationships in the sub-pixel according to the sixth embodiment are different from those in the second embodiment described above in that the first control transistor TR1 is additionally disposed between the fourth transistor T4 and the organic light emitting diode OLED. Therefore, only the portion regarding the fourth transistor T4, the first control transistor TR1, and the organic light emitting diode OLED will be additionally described.

[0133] The fourth transistor T4 may have a gate connected to the Nth light emission control line EM[n], a first electrode connected to the second electrode of the driving transistor DT, and a second electrode connected to the first electrode of the first control transistor TR1. The fourth transistor T4 may be used to transmit a driving current generated from the driving transistor DT to the first electrode of the fourth transistor T4 in response to the Nth light emission control signal Em[n] applied through the Nth light emission control line EM[n]. That is, the fourth transistor T4 is a light emission control transistor that controls light emission of the organic light emitting diode OLED.

[0134] The first control transistor TR1 may have a gate connected to the node control signal line CS, a first electrode connected to the second electrode of the fourth transistor T4, and a second electrode connected to the anode of the organic light emitting diode OLED and the first electrode of the sixth transistor T6. The first control transistor TR1 may be used to transmit the driving current transmitted from the fourth transistor T4 to the anode of the organic light emitting diode OLED during the display operation period. To this end, the first control transistor TR1 may be turned on during the display operation period and turned off during the touch operation period.

[0135] The anode of the organic light emitting diode OLED may be connected to the second electrode of the first control transistor TR1 and the first electrode of the sixth transistor T6, and the cathode of the organic light emitting diode OLED may be connected to the input terminal of the selector SEL. The organic light emitting diode OLED may be used to emit light based on the driving current from the driving transistor DT.

[0136] The selector SEL may be included in the sub-pixel or disposed outside the sub-pixel. The outside of the sub-pixel may represent a non-luminous area included in the display area of ​​the display panel and a non-display area outside the display area. The selector SEL may connect the cathode of the organic light emitting diode OLED to the second power line EVSS or the touch sensing line SL in response to a selection signal Mux applied through the selection signal line MUX.

[0137] The touch driver 145 may include a preamplifier AMP, a feedback capacitor Cfb, and a sensing channel SCH. The touch driver 145 may be electrically connected to a cathode of the organic light emitting diode OLED through a touch sensing line SL connected to the sensing channel SCH.

[0138] A single sub-pixel may operate in the initialization period INIT, the sampling period SAM, the holding period HOL, and the light emitting period EMP.

[0139] The operations of the transistors included in the subpixels in the initialization period INIT, the sampling period SAM, the holding period HOL, and the light emission period EMP are similar to those in the second embodiment. Therefore, the modified parts in the display operation period Display and the touch operation period Touch will be described emphatically.

[0140] like Fig.24 and Fig.25 As shown, the third transistor T3, the driving transistor DT, the fourth transistor T4 and the first control transistor TR1 can be turned on in the display operation period Display. The selector SEL can connect the cathode of the organic light emitting diode OLED to the second power line EVSS in the display operation period Display in response to the selection signal Mux. Therefore, the organic light emitting diode OLED can emit light based on the driving current Ioled transmitted by the turned-on first control transistor TR1 in the display operation period.

[0141] like Fig.24 and Fig.26 As shown, the driving transistor DT, the fourth transistor T4 and the first control transistor TR1 can be turned off in the touch working period Touch. The selector SEL can connect the cathode of the organic light emitting diode OLED to the touch sensing line SL in response to the selection signal Mux in the touch working period. Therefore, the touch driver 145 can obtain the touch sensing value Tsen through the cathode of the organic light emitting diode OLED in the touch working period Touch.

[0142] As described above, the cathode of the organic light emitting diode OLED serves as a touch electrode during the touch operating period Touch, and thus may receive and sense a user input in the form of a touch.

[0143] The light emission period EMP of the organic light emitting diode OLED may start (light emission on) when the Nth light emission control signal Em[n] is converted from a logic high level H to a logic low level L, and may end (light emission off) when it is converted from a logic low level L to a logic high level H. Therefore, the touch operation period Touch may correspond to a period in which the Nth light emission control signal Em[n] maintains a logic high level H.

[0144] Therefore, an example has been described in which the cathode of the organic light emitting diode OLED is electrically suspended during the period in which the selection signal Mux or the Nth light emitting control signal Em[n] maintains the logic high level H. However, the cathode of the organic light emitting diode OLED may be configured so that when the selection signal Mux is at a logic low level instead of a logic high level H, the cathode of the organic light emitting diode OLED is electrically suspended.

[0145] In addition, although an example has been described in which the node control signal Cs is generated at a logic high level H in the display operation period Display and is generated at a logic low level L in the touch operation period Touch, the present invention is not limited thereto. That is, an example has been described in which the node control signal Cs has a phase opposite to that of the Nth light emitting control signal Em[n], but the present invention is not limited thereto.

[0146] Fig. 27 2 is a diagram showing a touch electrode and a touch driver according to a seventh embodiment of the present invention, Fig.28 2 is a waveform diagram for describing a driving method according to a seventh embodiment of the present invention.

[0147] Hereinafter, a seventh embodiment of the present invention modified from the sixth embodiment will be described focusing on portions modified from the sixth embodiment.

[0148] like Fig. 27 and Fig.28 As shown, a single sub-pixel may further include a first n-type control transistor TR1 and a second n-type control transistor TR2. The first control transistor TR1 may be disposed between the fourth transistor T4 and the anode of the organic light emitting diode OLED. The second control transistor TR2 may be disposed between the cathode of the organic light emitting diode OLED and the sensing channel SCH of the touch driver 145.

[0149] The first control transistor TR1 may have a gate connected to the first node control signal line CS1 , a first electrode connected to the second electrode of the fourth transistor T4 , and a second electrode connected to the anode of the organic light emitting diode OLED and the first electrode of the sixth transistor T6 .

[0150] The first control transistor TR1 can be turned on in the display working period Display and turned off in the touch working period Touch. To this end, the first node control signal Cs1 sent through the first node control signal line CS1 can be applied at a logic high level H in the display working period Display and applied at a logic low level L in the touch working period Touch.

[0151] The second control transistor TR2 may have a gate connected to the second node control signal line CS2 , a first electrode connected to the touch sensing line SL, and a second electrode connected to the cathode of the organic light emitting diode OLED.

[0152] The second control transistor TR2 can be turned off in the display working period Display and turned on in the touch working period Touch. To this end, the second node control signal Cs2 sent through the second node control signal line CS2 can be applied at a logic low level L in the display working period Display and applied at a logic high level H in the touch working period Touch.

[0153] Fig.29 is a diagram showing a touch electrode and a touch driver according to an eighth embodiment of the present invention, Fig.30 0 is a waveform diagram for describing a driving method according to an eighth embodiment of the present invention. Hereinafter, an eighth embodiment of the present invention modified from the seventh embodiment will be described focusing on portions modified from the seventh embodiment.

[0154] like Fig.29 and Fig.30 As shown, a single sub-pixel may further include a first p-type control transistor TR1 and a second n-type control transistor TR2. The first control transistor TR1 may be disposed between the fourth transistor T4 and the anode of the organic light emitting diode OLED. The second control transistor TR2 may be disposed between the cathode of the organic light emitting diode OLED and the sensing channel SCH of the touch driver 145.

[0155] The first control transistor TR1 may have a gate connected to the node control signal line CS, a first electrode connected to the second electrode of the fourth transistor T4 , and a second electrode connected to the anode of the organic light emitting diode OLED and the first electrode of the sixth transistor T6 .

[0156] The second control transistor TR2 may have a gate connected to the node control signal line CS, a first electrode connected to the touch sensing line SL, and a second electrode connected to the cathode of the organic light emitting diode OLED.

[0157] The first control transistor TR1 may be turned on in the display operation period Display, and turned off in the touch operation period Touch. The second control transistor TR2 may be turned off in the display operation period Display, and turned on in the touch operation period Touch.

[0158] The node control signal Cs transmitted through the node control signal line CS may be applied at a logic low level L in the display operation period Display, and applied at a logic high level H in the touch operation period Touch. Therefore, when the first control transistor TR1 is configured as a p-type transistor and the second control transistor TR2 is configured as an n-type transistor, the two transistors TR1 and TR2 may share a single node control signal line CS, and thus may overcome disadvantages due to an increase in the number of signal lines and design difficulties due to the setting of the signal lines.

[0159] Fig.31 1 is a diagram showing a touch electrode and a touch driver according to a ninth embodiment of the present invention. Hereinafter, for convenience of explanation, the ninth embodiment of the present invention will be described centering on a portion modified from the fourth embodiment, which is a modified embodiment mentioned when implementing the first to fourth embodiments.

[0160] like Fig.31 As shown, in the ninth embodiment, the anode of the organic light emitting diode OLED can be used as a touch electrode in the touch operation period Touch. To this end, the first control transistor TR1 can be turned off in the touch operation period Touch. However, even in the touch operation period Touch for initializing the anode of the organic light emitting diode OLED, the first control transistor TR1 can be turned on only in the same period as the period in which the sixth transistor T6 is turned on.

[0161] The first control transistor TR1 may be configured as a p-type transistor. The first control transistor TR1 may have a gate connected to the node control signal line CS, a first gate connected to the second electrode of the fourth transistor T4 and the first electrode of the sixth transistor T6, and a second electrode connected to the anode of the organic light emitting diode OLED and the touch sensing line SL.

[0162] Similar to the fourth transistor T4 connected to the light emitting control signal line EM[n], the first control transistor TR1 can be turned on in the display working period Display and turned off in the touch working period Touch. Therefore, the first control transistor TR1 can be connected to the light emitting control signal line EM[n] like the fourth transistor T4. That is, the ninth embodiment can overcome the disadvantages caused by the increase in the number of signal lines and the design difficulties caused by the setting of the signal lines.

[0163] In addition, based on the first control transistor TR1 that is turned off in the touch operation period Touch, the ninth embodiment can improve the electrical independence of the anode of the organic light emitting diode OLED used as the touch electrode. In other words, when the anode of the organic light emitting diode OLED is used as the touch electrode, the blocking of electrical interference that may be caused by the operation of the transistors (e.g., T4 and T6) can be enhanced. Therefore, the ninth embodiment can improve the operating independence of the device for emitting light of the sub-pixel (display operation) and the operating independence of the device for touch sensing (touch operation).

[0164] Meanwhile, unlike the fourth embodiment, the second control transistor is not provided in the ninth embodiment. However, the second control transistor may depend on the sensing method of the touch driver 145, and thus the second control transistor may be added as in the fourth embodiment or may be omitted.

[0165] Fig.32 1 is a diagram showing a touch electrode and a touch driver according to a tenth embodiment of the present invention. Hereinafter, for the sake of convenience of explanation, the tenth embodiment of the present invention will be described centering on a portion modified from the eighth embodiment, which is a modified embodiment mentioned when implementing the fifth to eighth embodiments.

[0166] like Fig.32 As shown, in the tenth embodiment, the cathode of the organic light emitting diode OLED can be used as a touch electrode in the touch operation period Touch. To this end, the first control transistor TR1 can be turned off in the touch operation period Touch. However, even in the touch operation period Touch for initializing the anode of the organic light emitting diode OLED, the first control transistor TR1 can be turned on only in the same period as the period in which the sixth transistor T6 is turned on.

[0167] The first control transistor TR1 may be configured as a p-type transistor and may have a gate connected to the node control signal line CS, a first gate connected to the second electrode of the fourth transistor T4 and the first electrode of the sixth transistor T6, and a second electrode connected to the anode of the organic light emitting diode OLED.

[0168] Similar to the fourth transistor T4 connected to the light emitting control signal line EM[n], the first control transistor TR1 can be turned on in the display working period Display and turned off in the touch working period Touch. Therefore, the first control transistor TR1 can be connected to the light emitting control signal line EM[n] like the fourth transistor T4. That is, the tenth embodiment can overcome the disadvantages caused by the increase in the number of signal lines and the design difficulties caused by the setting of the signal lines.

[0169] The tenth embodiment can improve the electrical independence of the cathode of the organic light emitting diode OLED serving as a touch electrode based on the operation of the first control transistor TR1 turned off in the touch operating period and the operation of the selector SEL connecting the cathode of the organic light emitting diode OLED to the touch sensing line SL.

[0170] In other words, when the cathode of the organic light emitting diode OLED is used as a touch electrode, the blocking of electrical interference that may be caused by the operation of the transistors (e.g., T4 and T6) can be enhanced. Therefore, the tenth embodiment can improve the operation independence of the device for light emission of the sub-pixel (display operation) and the operation independence of the device for touch sensing (touch operation).

[0171] Meanwhile, unlike the eighth embodiment, the second control transistor is not provided in the tenth embodiment. However, the second control transistor may depend on the sensing method of the touch driver 145, and thus the second control transistor may be added as in the eighth embodiment or may be omitted.

[0172] The present invention can realize a touch sensor based on an anode or cathode included in a light-emitting diode to reduce the thickness of a touch display device and reduce the number and manufacturing cost of a display panel including a touch sensor. In addition, when a touch sensor is realized based on an anode or cathode included in a light-emitting diode, the present invention can overcome the disadvantages caused by an increase in the number of signal lines and the design difficulties caused by the setting of the signal lines. In addition, when a touch sensor is realized based on an anode or cathode included in a light-emitting diode, the present invention can improve the blocking of electrical interference between devices.

[0173] CROSS-REFERENCE TO RELATED APPLICATIONS

[0174] This application claims the benefit of Korean Patent Application No. 10-2020-0189501, filed on Dec. 31, 2020, which is hereby incorporated by reference as if fully set forth herein.

Claims

1. A touch display device, comprising: A display panel, the display panel comprising sub-pixels; a touch sensor including a touch electrode formed based on an electrode of a light emitting diode included in a sub-pixel; as well as a touch driver configured to sense the touch sensor, wherein the electrode of the light emitting diode is used as the touch electrode during a cut-off period of a light emitting control transistor for controlling light emission of the light emitting diode, Wherein, the electrode of the light emitting diode is an anode or a cathode, The touch display device further includes a first control transistor, which is arranged between the second electrode of the light emitting control transistor and the anode of the light emitting diode, and The first control transistor is turned on during a display operation period for displaying an image on the display panel.

2. The touch display device according to claim 1, wherein: The cathode of the light emitting diode is connected to a low voltage power line during a display operation period for displaying an image on the display panel.

3. The touch display device according to claim 1, wherein: The cathode of the light emitting diode is electrically suspended or electrically connected to the touch driver during a touch operation period for touch sensing of the touch sensor.

4. The touch display device according to claim 1, further comprising a second control transistor, wherein the second control transistor is arranged between the anode of the light emitting diode and the sensing channel of the touch driver, in, The second control transistor is turned on in a touch operation period for touch sensing of the touch sensor.

5. The touch display device according to claim 4, wherein: Each of the first control transistor and the second control transistor is configured as an n-type transistor or a p-type transistor.

6. The touch display device according to claim 1, wherein: The touch driver performs a sensing operation through the electrode of the light emitting diode during a cut-off period of the light emitting control transistor.

7. The touch display device according to claim 1, further comprising: a selector configured to connect the cathode of the light emitting diode to a low voltage power line during a display operation period for displaying an image on the display panel, and to electrically suspend the cathode of the light emitting diode during a touch operation period for touch sensing of the touch sensor; as well as a second control transistor, the second control transistor being disposed between the anode of the light emitting diode and the sensing channel of the touch driver and being turned on during the touch working period, Wherein, the electrode of the light emitting diode is an anode.

8. The touch display device according to claim 1, further comprising: a selector configured to connect the cathode of the light emitting diode to the low voltage power line during a display operation period for displaying an image on the display panel, and to electrically connect the cathode of the light emitting diode to the touch driver during a touch operation period for touch sensing of the touch sensor, Wherein, the electrode of the light emitting diode is a cathode.

9. The touch display device according to claim 1, further comprising: a second control transistor, which is disposed between a cathode of the light emitting diode and a sensing channel of the touch driver and is turned on during a touch operation period for touch sensing of the touch sensor, Wherein, the electrode of the light emitting diode is a cathode.

10. A method for driving a touch display device, the touch display device comprising: A display panel including sub-pixels; a touch sensor including a touch electrode formed based on an electrode of a light emitting diode included in the sub-pixel; and a touch driver configured to sense the touch sensor, the method comprising the following steps: causing the sub-pixel to emit light during a display operation period for displaying an image on the display panel; and sensing one of the electrodes of the light emitting diode during a touch operation period for touch sensing of the touch sensor, wherein the one electrode of the light emitting diode is used as the touch electrode during a cut-off period of a light emitting control transistor for controlling light emission of the light emitting diode, wherein the one electrode of the light emitting diode is an anode or a cathode, and The step of sensing the one electrode of the electrodes of the light emitting diode comprises the following steps: The first control transistor is turned off in the touch operation period, and the first control transistor is arranged between the second electrode of the light emitting control transistor and the anode of the light emitting diode.

11. The method according to claim 10, wherein: The step of sensing one of the electrodes of the light emitting diode further comprises the following steps: causing the cathode of the light emitting diode to be electrically suspended during the touch operation period; Turning on a second control transistor, the second control transistor being disposed between an anode of the light emitting diode and a sensing channel of the touch driver; and An anode of the light emitting diode is sensed.

12. The method according to claim 10, wherein: The step of sensing one of the electrodes of the light emitting diode further comprises the following steps: electrically connecting the cathode of the light emitting diode to the touch driver during a touch operation period; and A cathode of the light emitting diode is sensed.

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