Touch display device, touch driving circuit and display panel

Abstract

Embodiments of the present disclosure relate to a touch display device, a touch driving circuit, and a display panel. The touch display device of the present disclosure includes: a display panel having a plurality of touch electrodes electrically connected to a plurality of touch lines; a gate driving circuit configured to provide a scanning signal to the display panel through a plurality of gate lines; a touch driving circuit configured to sense a touch by detecting touch signals from the plurality of touch electrodes and provide a common voltage to the touch electrodes through the touch lines; a common voltage feedback line electrically connected to the plurality of touch lines or disposed to overlap the plurality of gate lines in a non-display area of the display panel; and a common voltage compensation circuit configured to provide a compensated common voltage based on distortion of the common voltage.

Description

[0001] Cross-reference to Related Applications

[0002] This application claims priority to Korean Patent Application No. 10-2020-0184904, filed on Dec. 28, 2020, which is hereby incorporated by reference in its entirety for all purposes. Technical Field

[0003] Embodiments herein relate to a touch display device, a touch driving circuit, and a display panel. Background Art

[0004] With the development of multimedia, the importance of flat panel display devices has been increasing. In response, flat panel display devices such as liquid crystal displays, plasma display panels, and organic light emitting displays have been commercialized.

[0005] In addition, by utilizing the characteristic that the electrical characteristics (such as resistance or capacitance) of a touch point change when a hand or a stylus touches, a touch display device in which a touch panel is stacked on such a flat panel display device has been widely used, where the touch panel generates information corresponding to the touch point from the sensing of the touch point or performs calculations related to the touch operation.

[0006] Such touch display devices are a type of user interface, and their applications are expanding to small portable terminals, office equipment, mobile devices, and so on.

[0007] However, when the touch panel is separately stacked on the flat panel display device, the touch display device becomes thicker. Therefore, there are limitations in manufacturing thin touch display devices, and passing through the stacked touch panel reduces the light transmittance efficiency and also increases the manufacturing cost. To solve such problems, an advanced in-cell touch (AIT) type display device in which touch electrodes are embedded in the pixel region of the display panel has been recently proposed.

[0008] Meanwhile, the load of the touch electrodes provided in the display panel increases as the size and resolution of the touch display device increase. Accordingly, there is a possibility that an image displayed on the display panel may be distorted due to the distortion of the common voltage supplied to the touch electrodes. Summary of the Invention

[0009] Embodiments may provide a touch display device, a touch driving circuit, and a display panel capable of reducing a distortion phenomenon of a common voltage caused by a touch electrode load.

[0010] In addition, an embodiment can provide a touch display device, a touch driving circuit, and a display panel that can effectively reduce the common voltage distortion phenomenon through a feedback structure of a common voltage supplied to a touch electrode.

[0011] In addition, an embodiment can provide a touch display device, a touch driving circuit, and a display panel that can change the structure of a common voltage feedback line according to the structure of a touch electrode, thereby effectively detecting and compensating for common voltage distortion.

[0012] According to one aspect, an embodiment can provide a touch display device including: a display panel including a plurality of touch electrodes disposed in a display area for displaying an image, the plurality of touch electrodes being electrically connected to a plurality of touch lines extending in a first direction; a gate driving circuit for providing a scanning signal to the display panel through a plurality of gate lines extending in a second direction different from the first direction; a touch driving circuit for detecting a touch signal from the plurality of touch electrodes during a touch driving period to sense a touch, and supplying a common voltage to the plurality of touch electrodes through the plurality of touch lines to display an image during a display driving period; a common voltage feedback line disposed in a non-display area of the display panel, electrically connected to the plurality of touch lines or overlapping with the plurality of gate lines in the non-display area of the display panel; and a common voltage compensation circuit for detecting distortion of the common voltage and providing a compensation common voltage based on the distortion of the common voltage through the plurality of touch lines.

[0013] According to one aspect, the plurality of touch electrodes are split-type touch electrodes, and at least two of the plurality of touch electrodes have the same size.

[0014] According to one aspect, the plurality of touch electrodes are woven-type touch electrodes, wherein a plurality of first touch electrodes having a first length in the second direction and a plurality of second touch electrodes having a second length in the second direction are alternately arranged along the first direction, the second length being shorter than the first length, and at least a part of the plurality of second touch electrodes arranged along the first direction is connected to one of the plurality of touch lines.

[0015] According to one aspect, the common voltage feedback line electrically connected to the plurality of touch lines is arranged such that the display area is located between the common voltage feedback line and the touch driving circuit.

[0016] According to one aspect, an embodiment can provide a touch display device further including a noise isolation circuit disposed between the common voltage feedback line and the plurality of touch lines.

[0017] According to one aspect, the noise isolation circuit includes a resistor and a capacitor, and the resistor and the capacitor are connected in parallel.

[0018] According to one aspect, the common voltage feedback line overlapping the plurality of gate lines is arranged along the first direction such that the display area is located between the gate driving circuit and the common voltage feedback line.

[0019] According to one aspect, the width of the common voltage feedback line corresponds to the length of the touch electrodes among the plurality of touch electrodes that overlap the plurality of gate lines in the second direction.

[0020] According to one aspect, the ratio of the width of the overlap between the common voltage feedback line and the first gate line among the plurality of gate lines to the width of the overlap between the common voltage feedback line and the second gate line among the plurality of gate lines is equal to the ratio of the length of the overlap between the first gate line and the first touch electrode among the plurality of touch electrodes to the length of the overlap between the second gate line and the second touch electrode among the plurality of touch electrodes.

[0021] According to one aspect, the compensated common voltage is a signal for canceling the distortion of the common voltage caused by the parasitic capacitance generated due to the overlap of the scan signals supplied through adjacent gate lines among the plurality of gate lines.

[0022] According to one aspect, the common voltage compensation circuit includes an operational amplifier, the operational amplifier includes an inverting input terminal and a non-inverting input terminal, the inverting input terminal receives the common voltage fed back through the common voltage feedback line via a first resistor, and the non-inverting input terminal receives a reference voltage.

[0023] According to another aspect, an embodiment may provide a touch driving circuit, including: a plurality of touch lines extending in one direction for transmitting touch signals to a display panel including a plurality of touch electrodes; a touch sensing circuit for providing a touch driving signal to the plurality of touch electrodes through the plurality of touch lines and receiving a touch sensing signal from the plurality of touch electrodes during a touch driving period, and providing a common voltage to the plurality of touch electrodes through the plurality of touch lines during a display driving period; a touch controller for detecting the presence of a touch in response to the touch sensing signal and calculating a touch coordinate based on the touch sensing signal; a common voltage feedback line electrically connected to the plurality of touch lines or overlapping the plurality of gate lines; and a common voltage compensation circuit for detecting the distortion of the common voltage and providing a compensated common voltage generated based on the distortion of the common voltage through the plurality of touch lines.

[0024] According to another aspect, an embodiment may provide a display panel including: a plurality of touch electrodes, each of the plurality of touch electrodes corresponding to a plurality of sub-pixels respectively; a plurality of touch lines extending in a first direction, the plurality of touch lines being configured to transmit touch signals to the plurality of touch electrodes; a plurality of gate lines extending in a second direction different from the first direction, the plurality of gate lines being configured to transmit scan signals to the plurality of sub-pixels; and a common voltage feedback line electrically connected to the plurality of touch lines or overlapping with the plurality of gate lines in a non-display area.

[0025] According to an exemplary embodiment, a touch display device, a touch driving circuit, and a display panel capable of reducing a common voltage distortion phenomenon caused by a touch electrode load may be provided.

[0026] According to an exemplary embodiment, a touch display device, a touch driving circuit, and a display panel capable of effectively reducing a common voltage distortion phenomenon through a feedback structure of a common voltage supplied to a touch electrode may be provided.

[0027] According to an exemplary embodiment, a touch display device, a touch driving circuit, and a display panel capable of changing a structure of a common voltage feedback line according to a structure of a touch electrode, thereby effectively detecting and compensating for a common voltage distortion, may be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other objects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description in conjunction with the accompanying drawings, in which:

[0029] Figure 1 A block diagram of a touch display device according to an embodiment of the present disclosure is shown;

[0030] Figure 2 A structure of a touch electrode in a touch display device according to an embodiment of the present disclosure is shown;

[0031] Figure 3 A timing for configuring a display driving period and a touch driving period in a touch display device according to an embodiment of the present disclosure is shown;

[0032] Figure 4 A part of a touch electrode in a touch display device according to an embodiment of the present disclosure is shown;

[0033] Figure 5 A schematic diagram for showing a common voltage distortion phenomenon caused by scan signal overlap in a touch display device according to an embodiment of the present disclosure is shown;

[0034] Figure 6Shows a structure in a touch display device according to an embodiment of the present disclosure, where a common voltage feedback line is set to be connected to a touch line;

[0035] Figure 7 Shows an exemplary common voltage compensation circuit for generating a compensated common voltage to compensate for common voltage distortion in a touch display device according to an embodiment of the present disclosure;

[0036] Figure 8 Shows an exemplary diagram of a structure in a touch display device according to an embodiment of the present disclosure, where a common voltage feedback line is set to form a capacitor with a gate line;

[0037] Figure 9 Shows a display panel with a braided touch electrode in a touch display device according to an embodiment of the present disclosure;

[0038] Figure 10 Shows an exemplary structure of a common voltage feedback line formed by reflecting a touch electrode overlapping a gate line in a touch display device according to an embodiment of the present disclosure. Detailed Description of the Invention

[0039] In the following description of examples or embodiments of the present invention, reference will be made to the accompanying drawings, which illustrate by way of example the examples or embodiments that can be implemented. In the drawings, the same reference numerals and symbols may be used to represent the same or similar components, even if they are shown in different drawings. Further, in the following description of examples or embodiments of the present invention, if it is determined that a detailed description of well-known functions or components introduced herein may obscure the subject matter of some embodiments of the present invention, then such description will be omitted. Unless used in conjunction with the term "only", terms such as "including", "having", "containing", "comprising", "consisting of", and "formed of" as used herein are generally intended to allow the addition of other components. Unless otherwise clearly indicated in the context, the singular forms used herein are intended to include the plural forms.

[0040] Terms such as "first", "second", "A", "B", "(A)", or "(B)" may be used herein to describe elements of the present invention. None of these terms is used to define the essence, order, sequence, or quantity, etc. of the elements, but is merely used to distinguish the corresponding elements from other elements.

[0041] When referring to the first component being "connected or coupled", "contacting or overlapping", etc. with the second component, it should be understood that the first component can not only be "directly connected or coupled" or "directly contacting or overlapping" with the second component, but also a third component can be "inserted" between the first component and the second component, or the first and second components can be "connected or coupled", "contacting or overlapping", etc. with each other through a fourth component. Here, the second component can include at least one of two or more components that are "connected or coupled", "contacting or overlapping", etc. with each other.

[0042] When using time-related terms such as "after", "subsequently", "next", and "before" to describe the processing or operation of components or configurations or the flow or steps in an operation, process, or manufacturing method, these terms can be used to describe non-consecutive or non-sequential processing or operations unless used together with the terms "directly" or "immediately".

[0043] Furthermore, when referring to any dimensions, relative dimensions, etc., even if no relevant description is specified, the numerical values or corresponding information (such as grades, ranges, etc.) of elements or features should be considered to include the tolerance or error range that may be caused by different factors (such as processing factors, internal or external influences, noise, etc.). Further still, the term "can" fully encompasses all the meanings of the term "may".

[0044] Figure 1 A block diagram of a touch display device according to an embodiment of the present disclosure is shown.

[0045] Reference Figure 1 , the touch display device according to the embodiment may include a display panel 110, a gate driving circuit 120, a data driving circuit 130, a touch driving circuit 160, a timing controller (T-CON) 140, and a micro control unit (microcontroller) 150.

[0046] The display panel 110 displays an image based on a scan signal transmitted from the gate driving circuit 120 through a gate line GL and digital image data DATA transmitted from the data driving circuit 130 through a data line DL.

[0047] For a liquid crystal display device, the display panel 110 can operate in any known mode, such as a twisted nematic (TN) mode, a vertical alignment (VA) mode, an in-plane switching (IPS) mode, or an fringe field switching (FFS) mode. On the other hand, for an organic light emitting display device, the display panel 110 can be implemented as a top emission structure, a bottom emission structure, or a double emission structure.

[0048] Multiple sub-pixels SP of the display panel 110 may be defined by a plurality of data lines DL and a plurality of gate lines GL. A single sub-pixel SP may include a thin film transistor (TFT) disposed in an area where a single data line DL intersects with a single gate line GL, a light emitting component (e.g., an organic light emitting diode) charged with a data voltage Vdata, and a storage capacitor Cst electrically connected to the light emitting component to hold a voltage, and so on.

[0049] A black matrix, a color filter, and so on may be provided on the upper substrate of the display panel 110, while the thin film transistor, the sub-pixel SP, the common electrode CE, and so on may be provided on the lower substrate of the display panel 110. A color filter on TFT (COT) structure may be used to provide the display panel 110. In this case, the black matrix and the color filter may be provided on the lower substrate of the display panel 110.

[0050] A common electrode supplied with a common voltage may be provided on the upper substrate or the lower substrate of the display panel 110. Polarizers may be attached to the upper substrate and the lower substrate of the display panel 110, and an alignment film for setting the tilt angle of liquid crystal molecules may be provided on the inner surface of the upper substrate or the lower substrate in contact with the liquid crystal layer.

[0051] Column spacers for maintaining a cell gap for holding liquid crystal cells are provided between the upper substrate and the lower substrate of the display panel 110. In the liquid crystal display device, a backlight unit is disposed below the bottom surface of the lower polarizer of the display panel 110. The backlight unit may be implemented as an edge type backlight unit or a direct type backlight unit to illuminate the display panel 110.

[0052] Here, a touch panel having an in-cell touch structure may be embedded in the pixel array region of the display panel 110. The in-cell touch panel uses, for example, block (or dot) electrodes provided inside the display panel 110 as touch electrodes.

[0053] The timing controller 140 controls the gate driving circuit 120 and the data driving circuit 130. The timing controller 140 receives timing signals, such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a data enable signal DE, and a main clock signal MCLK, from a host system (not shown), and also receives digital image data DATA of an image signal.

[0054] The timing controller 140 controls the gate driving circuit 120 based on scan timing control signals (such as a gate start pulse signal GSP, a gate shift clock signal GSC, and a gate output enable signal GOE). In addition, the timing controller 140 also controls the data driving circuit 130 based on data timing control signals (such as a source sampling clock signal SSC, a source start pulse SSP, and a source output enable signal SOE).

[0055] The gate driving circuit 120 sequentially drives a plurality of gate lines GL by sequentially providing scan signals to the display panel 110 via the plurality of gate lines GL. Here, the gate driving circuit 120 may also be referred to as a scan driving circuit or a gate driving integrated circuit (GDIC).

[0056] The gate driving circuit 120 may include one or more gate driving integrated circuits (GDICs), and may be located on one or both sides of the display panel 110 or adjacent thereto according to the driving method. Alternatively, the gate driving circuit 120 may also be implemented using an in-panel gate structure in which the gate driving circuit 120 is embedded in the border area of the display panel 110.

[0057] Under the control of the timing controller 140, the gate driving circuit 120 sequentially provides scan signals having an on or off voltage to the plurality of gate lines GL. In this regard, the gate driving circuit 120 may include a shift register, a level shifter, and the like.

[0058] The data driving circuit 130 drives the plurality of data lines DL by providing digital image data DATA received from the timing controller 140 to the plurality of data lines DL. Here, the data driving circuit 130 may also be referred to as a source driving circuit or a source driving integrated circuit (SDIC).

[0059] The data driving circuit 130 may include one or more source driving integrated circuits (SDICs). The source driving integrated circuit (SDIC) may be connected to the pads of the display panel 110 by a tape automated bonding (TAB) method or a chip on glass (COG) method, may be directly mounted on the display panel 110, or in some cases may be provided as an integral part of the display panel 110. In addition, the source driving integrated circuit (SDIC) may be implemented using a chip on film (COF) structure. In this case, the source driving integrated circuit may be mounted on a circuit film and may be electrically connected to the data lines DL of the display panel 110 via the circuit film.

[0060] When a specific gate line GL is turned on by the gate driving circuit 120, the data driving circuit 130 converts the digital image data DATA received from the timing controller 140 into an analog data voltage and provides the analog data voltage to the plurality of data lines DL.

[0061] Depending on the driving method, design, etc., the data driving circuit 130 may be located above or below (or on the upper or lower side) of the display panel 110, or may be located above and below (or on the upper and lower sides) of the display panel 110 at the same time.

[0062] The data driving circuit 130 may include a shift register, a latch circuit, a digital-to-analog converter (DAC), an output buffer, and the like. The digital-to-analog converter is a component for converting the digital image data received from the timing controller 140 into an analog data voltage provided to the data line DL.

[0063] The touch driving circuit 160 detects a touch on the display panel 110 and determines the touch position on the display panel 110. The touch driving circuit 160 may include a touch sensing circuit that generates a touch driving signal to drive the touch electrodes and receives the touch sensing signal generated in the touch electrodes, and a touch controller that processes the touch sensing signal to detect the presence of a touch and the touch coordinates. The touch sensing circuit and the touch controller of the touch driving circuit 160 may be implemented as a single integrated circuit called a readout integrated circuit (ROIC), or provided as separate circuits divided according to functions.

[0064] In addition, the source driver integrated circuit (SDIC) of the data driving circuit 130 and the readout integrated circuit (ROIC) of the touch driving circuit 160 may be combined into a combined integrated circuit (SRIC).

[0065] The touch driving circuit 160 may be provided on an external substrate connected to the display panel 110. The touch driving circuit 160 is connected to the display panel 110 via a plurality of touch lines TL. The touch driving circuit 160 may detect the presence of a touch and determine the touch position based on the capacitance difference between the touch electrodes in the display panel 110. That is, a capacitance difference occurs between the position where the user's finger is placed and the position where the finger is not placed, and the touch driving circuit 160 determines the presence and position of the touch by detecting this capacitance difference. The touch driving circuit 160 generates a touch sensing voltage regarding the presence and position of the touch, and transmits the touch sensing voltage to the micro control unit 150.

[0066] The micro control unit 150 controls the touch driving circuit 160. The micro control unit 150 may receive a control synchronization signal Csync from the timing controller 140, and generate a touch synchronization signal Tsync according to the control synchronization signal Csync to control the touch driving circuit 160. The micro control unit 150 transmits and receives touch sensing signals and the like to and from the touch driving circuit 160 based on the interface IF defined between it and the touch driving circuit 160.

[0067] Here, the micro control unit 150 may be combined with the touch driving circuit 160 into a touch control circuit composed of a single IC, or may be combined with the timing controller 140 into a control circuit composed of a single integrated circuit.

[0068] In addition, the touch display device may further include a memory. The memory may temporarily store digital image data DATA transmitted from the timing controller 140, and may provide the digital image data DATA to the data driving circuit 130 at a predetermined time. The memory may be disposed inside or outside the data driving circuit 130. If the memory is disposed outside the data driving circuit 130, the memory may be disposed between the timing controller 140 and the data driving circuit 130. In addition, the memory may include a buffer memory for storing digital image data DATA received from an external source and providing the stored digital image data DATA to the timing controller 140.

[0069] In addition, the touch display device may further include an interface capable of outputting and inputting signals to and from other external electronic devices or electronic components or capable of communicating therewith. As an example, the interface may include at least one of a serial peripheral interface (SPI), a low voltage differential signaling (LVDS) interface, or a mobile industry processor interface (MIPI).

[0070] Meanwhile, the touch display device 100 may sense the presence of a touch or touch coordinates based on the capacitance formed by the touch electrodes TE.

[0071] The touch display device 100 may sense a touch through a mutual capacitance scheme or a self-capacitance scheme, which are capacitance-based touch sensing schemes.

[0072] For the mutual capacitance-based touch sensing scheme, a plurality of touch electrodes may be classified into touch driving electrodes provided with touch driving signals through touch driving lines, and touch sensing electrodes that form a capacitance with the touch driving electrodes and provide touch sensing signals through touch sensing lines. Here, the touch driving lines and the touch sensing lines may be referred to as touch lines.

[0073] For the mutual capacitance-based touch sensing scheme, the presence of a touch and touch coordinates may be detected based on changes in the mutual capacitance formed between the touch driving electrodes and the touch sensing electrodes in accordance with the presence of an indicator (such as a finger or a pen, etc.).

[0074] For the self-capacitance-based touch sensing scheme, each touch electrode serves as both a touch driving electrode and a touch sensing electrode at the same time. That is, a touch driving signal is provided to the touch electrode through a touch line, and the touch sensing signal generated in the touch electrode provided with the touch driving signal is transmitted through the same touch line. Therefore, for the self-capacitance-based touch sensing scheme, there is no distinction between the touch driving electrode and the touch sensing electrode, and there is also no distinction between the touch driving line and the touch sensing line.

[0075] For a self - capacitance - based touch sensing scheme, the presence of a touch and the touch coordinates can be detected based on changes in the capacitance formed between an indicator (such as a finger or a pen, etc.) and a touch electrode TE.

[0076] Therefore, the touch display device 100 can sense touches through a mutual - capacitance - based touch sensing scheme or a self - capacitance - based touch sensing scheme.

[0077] Furthermore, such a touch display device 100 can be various types of display devices, such as a liquid crystal display device, an organic light - emitting display device, a plasma display panel, and a quantum dot display device, etc.

[0078] In the touch display device 100 according to an embodiment of the present disclosure, a plurality of touch electrodes can be arranged on the display panel 110, and these touch electrodes can be common electrodes provided with a common voltage for displaying an image.

[0079] When the touch display device 100 is an organic light - emitting display device, the touch display device 100 can include an organic light - emitting diode composed of a first electrode (anode), an organic light - emitting layer, and a second electrode (cathode), a packaging layer located above the second electrode and having a packaging function, and a touch sensor metal layer located on the packaging layer. Here, a plurality of touch electrodes TE can be formed on the touch sensor metal layer, or the touch electrode TE can be formed on the second electrode layer constituting the cathode of the organic light - emitting diode.

[0080] Meanwhile, the common voltage provided to the common electrode or the touch electrode can be a DC voltage, which has a specific voltage level during a predetermined time while the data voltage level provided to the display panel 110 changes during the display driving period. In addition, depending on the type of the liquid crystal display device or the organic light - emitting display device, the common voltage provided to the common electrode or the touch electrode can be used as a display voltage or other names.

[0081] Figure 2 The structure of the touch electrodes in the touch display device according to an embodiment of the present disclosure is shown.

[0082] Reference Figure 2 , in the touch panel of the touch display device 100 according to an embodiment of the present disclosure, it can be embedded in the pixel array region of the display panel 110 of the in - cell touch structure. In this case, the display panel 110 of the in - cell touch structure can use a common electrode CE configured in a block or dot pattern as the touch electrode TE.

[0083] In the display panel 110 of the embedded touch structure, a common electrode CE corresponding to a plurality of sub-pixels SP in the display panel 110 forms a touch electrode TE. The touch electrode TE can be defined by a common electrode CE formed separately from the display panel 110.

[0084] A plurality of touch electrodes TE can be arranged in rows in the display area of the display panel 110. Each touch electrode TE can be connected to a touch line TL to transmit a touch driving signal TDS and receive a touch sensing signal.

[0085] The touch electrode TE can be implemented as a touch sensor metal that senses a touch input using a capacitance-based touch sensing method. In this case, the touch electrode TE can receive a common voltage Vcom during a display driving period and receive a touch driving signal TDS during a touch driving period.

[0086] Figure 3 A timing for configuring a display driving period and a touch driving period in a touch display device according to an embodiment of the present disclosure is shown.

[0087] Reference Figure 3 , within a display frame period, the touch display device 100 according to an embodiment of the present disclosure performs a display driving process for displaying an image during a predefined display driving period DP and performs a touch driving process for sensing a touch input from a finger or a stylus during a predefined touch driving period TP.

[0088] The touch display device 100 uses a common electrode CE for driving each pixel as an electrode for sensing a touch. Accordingly, during the display driving period DP, a common voltage Vcom is supplied to a thin film transistor connected to the common electrode CE, and during the touch driving period TP, a touch driving signal TDS is supplied to the common electrode CE serving as the touch electrode TE.

[0089] The display driving period DP and the touch driving period TP can be equal in time, can overlap with each other in whole or in part in time, or can be separated from each other in time.

[0090] A driving method in which the display driving period DP and the touch driving period TP are separated from each other in time can be referred to as a time-division driving operation.

[0091] When the display driving period DP and the touch driving period TP are equal in time, the display driving operation and the touch driving operation can be performed simultaneously. This driving method can be referred to as a time-free driving operation.

[0092] In the time-division driving operation, the display driving period DP and the touch driving period TP can be arranged alternately.

[0093] Therefore, when the display driving period DP and the touch driving period TP are alternately arranged while being separated in time, the touch driving period TP can correspond to a blank period Blank during which the display driving operation is not performed.

[0094] The touch display device 100 can generate a touch synchronization signal Tsync that swings between a high level and a low level, and can thereby identify or control the display driving period DP and the touch driving period TP. That is to say, the touch synchronization signal Tsync can be a driving timing control signal for defining the touch driving period TP.

[0095] For example, the high-level period (or low-level period) of the touch synchronization signal Tsync can correspond to the display driving period DP, and the low-level period (or high-level period) of the touch synchronization signal Tsync can correspond to the touch driving period TP.

[0096] In this case, the touch driving circuit 160 can supply a touch driving signal TDS to the touch electrode TE during the touch driving period TP when the touch synchronization Tsync is at a low level, and can sense the touch presence and touch position of a passive stylus or an active stylus using the touch sensing signal received from the touch electrode TE.

[0097] Meanwhile, for a method of allocating the display driving period DP and the touch driving period TP in one display frame period, as an example, one display frame period can be divided into a display driving period DP and a touch driving period TP, and a display driving operation can be performed during a display driving period DP, and a touch driving operation for sensing touch inputs from a finger and a stylus can be performed during a touch driving period TP corresponding to the blank period Blank.

[0098] The touch display device 100 performs the display driving operation at the screen refresh rate or performs the display driving operation once in one display frame period corresponding to the frame frequency.

[0099] For example, when the frame frequency is 60 Hz, the display driving operation is performed to turn on or off pixels through N gate lines constituting the display panel 110 within a horizontal period of 1 / 60 second. Thereafter, the touch sensing operation is performed at a predetermined interval as the touch driving period TP. In this case, the touch reporting rate is 60 Hz.

[0100] In another example, a display frame period may be divided into two or more display driving periods DP and two or more touch driving periods TP, and a display driving operation may be performed during two or more display driving periods DP in a display frame period, and a touch driving operation may be performed during two or more touch driving periods TP in a display frame period to sense touch input from a finger and a stylus on the entire display screen or at least a part of the display screen one time or two or more times.

[0101] Thus, when a display frame period is divided into two or more display driving periods DP and two or more touch driving periods TP, and then the display driving operation and the touch driving operation are performed, each of the two or more blank periods corresponding to the two or more touch driving periods TP in a display frame period is sometimes referred to as a long horizontal blank (“LHB”).

[0102] Accordingly, the two or more periods for sensing touch from a stylus or a finger in a display frame period may be referred to as LHBs or touch driving periods TP, and the touch driving operation performed during the two or more LHBs in a touch frame period is referred to as an “LHB driving operation”.

[0103] Figure 4 A part of a touch electrode area in a touch display device according to an embodiment of the present disclosure is shown.

[0104] Reference Figure 4 , a touch display device 100 according to an embodiment of the present disclosure includes a plurality of thin film transistors TFT formed on a substrate, a plurality of pixel electrodes P11 - P44 connected to drain nodes or source nodes of the plurality of thin film transistors, and a touch electrode TE provided to overlap with the plurality of pixel electrodes P11 - P44 to form an electric field.

[0105] A gate node of the thin film transistor TFT is connected to a gate line controlled to be turned on and off according to a scan signal, and a source node or a drain node is connected to a data line DL provided with a data voltage.

[0106] At this time, when a passive stylus (e.g., a finger) or an active stylus touches the display panel 110, the touch display device 100 may recognize a capacitance change of the touch electrode TE near the touch pen contact position, and may detect the touch position. That is, the touch display device 100 may provide a touch driving signal to the touch electrode TE formed on the display panel 110, and then may sense the touch position by detecting the touch sensing signal received from the touch electrode TE and detecting the capacitance change of each touch electrode TE.

[0107] At this time, a common voltage Vcom or a touch driving signal TDS is supplied to a touch electrode TE of the touch display device 100, and thus a parasitic capacitance coupled to the touch electrode TE may be generated.

[0108] As an example, a scan signal supplied to the display panel 110 through a gate line may generate a parasitic capacitance between the gate line and the touch electrode TE. Due to this parasitic capacitance, the load on the touch electrode TE will increase, the common voltage supplied to the touch electrode TE will be distorted, and there may be defective lines on the display panel 110.

[0109] Figure 5 Shown is a schematic diagram for showing a phenomenon of common voltage distortion caused by scan signal overlap in a touch display device according to an embodiment of the present disclosure.

[0110] Refer to Figure 5 , the gate driving circuit 120 in the touch display device 100 according to an embodiment of the present disclosure may sequentially supply a scan signal SCAN to the display panel 110 through the gate lines at intervals of one horizontal period 1H.

[0111] In this case, the gate driving circuit 120 may maintain the scan signal SCAN at a high level for a certain period. Here, as an example, the shown case is that the high-level period of the scan signal SCAN is 5 horizontal periods 5H.

[0112] As described above, when supplying a scan signal SCAN having a predetermined high-level period transmitted to the display panel 110 through the gate line GL at intervals of one horizontal period 1H, an overlapping period is generated between adjacent scan signals SCAN.

[0113] Due to the overlapping period of the scan signal SCAN, a parasitic capacitance Cgc accumulates between the gate node of the thin film transistor TFT and the touch electrode TE supplied with the common voltage Vcom, and an increase in the load on the touch electrode TE may distort the common voltage Vcom.

[0114] In particular, in the touch display device 100 provided with a plurality of touch electrodes TE, since the distortion of the common voltage Vcom affects the touch sensitivity, it is difficult to form a feedback line for detecting the distortion of the common voltage Vcom supplied to the touch electrode TE.

[0115] Accordingly, the present disclosure may provide a common voltage feedback line for the touch display device 100, which can detect the distortion of the common voltage Vcom so as to minimize the influence on the touch electrode TE.

[0116] Figure 6Shows a structure in a touch display device according to an embodiment of the present disclosure where a common voltage feedback line is set to be connected to a touch line.

[0117] Referring Figure 6 , in the display panel 110 of the touch display device 100 according to an embodiment of the present disclosure, a common electrode CE configured in a block or dot pattern can be used as a touch electrode TE.

[0118] In the display panel 110, common electrodes CE corresponding to a plurality of sub-pixels SP formed in the display area AA constitute touch electrodes TE.

[0119] A plurality of touch electrodes TE can be arranged in a row in the display area AA of the display panel 110. Each touch electrode TE can be connected to a touch line TL, which is used to provide a touch drive signal TDS during a touch drive period TP and to receive a touch sensing signal. Here, as an example, the case where four (2X2) touch electrodes TE1 - TE4 are arranged in a matrix is shown.

[0120] At this time, the touch drive circuit 160 provides a common voltage Vcom to the sub-pixels SP during a display drive period DP, and provides a touch drive signal TDS through the touch line TL during the touch drive period TP.

[0121] In this case, due to the overlap of the scan signals provided by the gate lines GL1, GL2, parasitic capacitances Cgc1 - Cgc4 are generated between the gate lines GL1, GL2 and the touch electrodes TE1 - TE4, and the common voltage Vcom provided through the touch line TL during the display drive period DP may be distorted due to this parasitic capacitance.

[0122] The touch display device 100 of the present disclosure may include a common voltage feedback line FL for detecting distortion of the common voltage Vcom, which extends from the touch line TL along a non-display area positioned opposite to the touch drive circuit 160 based on the display area AA.

[0123] Specifically, the common voltage feedback line FL extending along the non-display area opposite to the touch drive circuit 160 can be electrically connected to a plurality of touch lines TL1 - TL4 in contact with the plurality of touch electrodes TE1 - TE4.

[0124] For the above purpose, the common voltage feedback line FL can be set along a direction perpendicular to the direction in which the plurality of touch lines TL1 - TL4 extend from the touch electrodes TE1 - TE4. Accordingly, when the gate lines GL1, GL2 are orthogonal to the touch lines TL1 - TL4, the common voltage feedback line FL can be set to be parallel to the gate lines GL1, GL2 in the non-display area and can be electrically connected to the touch lines TL1 - TL4.

[0125] In this case, the common voltage feedback line FL can extend along the non-display area and can be connected to a common voltage compensation circuit. The common voltage compensation circuit can detect the distortion of the common voltage and generate a compensated common voltage capable of canceling the distorted waveform of the common voltage Vcom from the common voltage feedback line FL, and can provide the compensated common voltage through the touch line TL.

[0126] The common voltage compensation circuit can be located inside the touch driving circuit 160 or can be located outside the touch driving circuit 160.

[0127] Meanwhile, a noise isolation circuit 170 can be provided between the touch line TL and the common voltage feedback line FL extending to the non-display area so as to minimize the influence of the common voltage feedback line FL on the touch electrode TE. As Figure 6 shown, each touch line TL is connected to the common voltage feedback line FL via the noise isolation circuit 170. Accordingly, a plurality of noise isolation circuits 170 are provided in the touch display device.

[0128] Each noise isolation circuit 170 can include a resistor R and a capacitor C connected in parallel between the touch line TL and the common voltage feedback line FL.

[0129] At this time, it is more preferable that the resistor R and the capacitor C constituting the noise blocking circuit 170 have a very high resistance and a very high capacitance so that the influence of the common voltage feedback line FL can be prevented from being transmitted to the touch electrode TE.

[0130] Accordingly, when the common voltage Vcom is distorted due to the parasitic capacitances Cgc1-Cgc4 formed between the gate lines GL1, GL2 and the touch electrodes TE1-TE4 by the scan signals SCAN provided through the gate lines GL1, GL2, the common voltage compensation circuit can detect the distortion of the common voltage Vcom through the common voltage feedback line FL and provide a compensated common voltage capable of compensating the distorted common voltage Vcom, thereby preventing image errors caused by the distortion of the common voltage Vcom.

[0131] Figure 7 An exemplary common voltage compensation circuit for generating a compensated common voltage to compensate for common voltage distortion in a touch display device according to an embodiment of the present disclosure is shown.

[0132] Reference Figure 7, the common voltage compensation circuit 162 in the touch display device 100 according to an embodiment of the present disclosure may include an operational amplifier OP. The operational amplifier receives, through a first resistor R1, the common voltage Vcom fed back through a common voltage feedback line FL extending from a touch electrode TE at an inverting input terminal (−), and receives a reference voltage Vref at a non-inverting input terminal (+). The common voltage compensation circuit 162 detects distortion of the common voltage Vcom fed back through the common voltage feedback line FL based on a comparison between the common voltage and the reference voltage Vref. The comparison between the common voltage and the reference voltage Vref yields a difference between signals representative of the distortion of the common voltage.

[0133] At this time, the reference voltage Vref provided to the non-inverting input terminal (+) may be a signal that is the same as or different from the common voltage Vcom provided through a touch line TL.

[0134] Since a second resistor R2 is connected between the inverting input terminal (−) and the output terminal of the operational amplifier OP, the operational amplifier OP generates a compensated common voltage Vcom_comp by inverting and amplifying the fed-back common voltage Vcom according to the ratio of the first resistor R1 to the second resistor R2.

[0135] Accordingly, the common voltage compensation circuit 162 provides the compensated common voltage Vcom_comp to the touch electrode TE through the touch line TL, thereby compensating for the distortion component of the compensated common voltage Vcom. The compensation operation for the common voltage Vcom may be performed by the common voltage compensation circuit 162 in each frame.

[0136] Meanwhile, in the touch display device 100 of the present disclosure, the common voltage feedback line FL may be disposed on an extension of the gate line GL to form a capacitor with the gate line GL, thereby detecting distortion of the common voltage Vcom caused by a parasitic capacitor Cgc formed between the gate line GL and the touch electrode TE.

[0137] Figure 8 FIG. shows an example diagram of a structure in which a common voltage feedback line is set to form a capacitor with a gate line in a touch display device according to an embodiment of the present disclosure.

[0138] Reference Figure 8 , the display panel 110 of the touch display device according to an embodiment of the present disclosure may use a common electrode CE configured in a block or dot pattern as the touch electrode TE.

[0139] A plurality of touch electrodes TE may be arranged in a row in the display area AA of the display panel 110. Each touch electrode TE may be connected to a touch line TL, which is used to provide a touch driving signal TDS during a touch driving period TP and to receive a touch sensing signal. Here, as an example, a case where four (2X2) touch electrodes TE1-TE4 are arranged in a matrix is shown.

[0140] At this time, the touch driving circuit 160 provides a common voltage Vcom to the sub-pixels SP during a display driving period DP, and provides a touch driving signal TDS through the touch line TL during a touch driving period TP.

[0141] As described above, since the overlap of the scan signals SCAN provided through the gate lines GL1, GL2 generates parasitic capacitances Cgc1-Cgc4 between the gate lines GL1, GL2 and the touch electrodes TE1-TE4, the common voltage Vcom provided through the touch line TL during the display driving period DP may be distorted.

[0142] To detect the distortion of the common voltage Vcom, the touch display device 100 of the present disclosure may include a common voltage feedback line FL provided in a non-display area in a direction intersecting the gate lines GL1, GL2, where the gate lines GL1, GL2 extend in the non-display area.

[0143] In this case, the non-display area provided with the common voltage feedback line FL may be an area opposite to the gate driving circuit 120 based on the display area AA, and the common voltage feedback line FL may extend along a direction intersecting the gate lines GL1, GL2.

[0144] When the gate lines GL1, GL2 are orthogonal to the touch lines TL1-TL4, the common voltage feedback line FL may be provided parallel to the touch lines TL1-TL4 in the non-display area.

[0145] As described above, when the common voltage feedback line FL is provided in the non-display area opposite to the gate driving circuit 120 in a direction intersecting the gate lines GL1, GL2, the common voltage feedback line FL may respectively form feedback capacitances Cfb1, Cfb2 in the area intersecting the gate lines GL1, GL2.

[0146] Accordingly, when the scan signals provided through the gate lines GL1, GL2 form parasitic capacitances Cgc1-Cgc4 between the gate lines GL1, GL2 and the touch electrodes TE1-TE4, feedback capacitances Cfb1, Cfb2 corresponding to the parasitic capacitances Cgc1-Cgc4 are formed in the common voltage feedback line FL.

[0147] Since the parasitic capacitances Cgc1-Cgc4 between the gate lines GL1, GL2 and the touch electrodes TE1-TE4 can be calculated by the feedback capacitances Cfb1, Cfb2 formed in the common voltage feedback line FL, the feedback capacitances Cfb1, Cfb2 can be detected and a compensation common voltage Vcom_comp capable of canceling the distorted waveform of the common voltage Vcom can be generated based on the feedback capacitances Cfb1, Cfb2.

[0148] For the above purpose, the common voltage feedback line FL extending along the non-display area can be connected to the common voltage compensation circuit 162. The common voltage compensation circuit 162 can generate a compensation common voltage Vcom_comp capable of canceling the distorted waveform of the common voltage Vcom detected through the common voltage feedback line FL, and can provide the compensation common voltage Vcom_comp through the touch line TL.

[0149] The common voltage compensation circuit 162 can be located inside the touch driving circuit 160, or can be located outside the touch driving circuit 160.

[0150] As described above, when the distortion of the common voltage Vcom occurs due to the parasitic capacitances Cgc1-Cgc4 formed between the gate lines GL1, GL2 and the touch electrodes TE1-TE4 by the scan signals SCAN provided through the gate lines GL1, GL2, the common voltage compensation circuit 162 can detect the distortion of the common voltage Vcom through the common voltage feedback line FL and provide a compensation common voltage capable of compensating the distorted common voltage Vcom, thereby preventing image errors caused by the distortion of the common voltage Vcom.

[0151] On the other hand, the distortion of the common voltage Vcom caused by the parasitic capacitance Cgc formed between the gate line GL and the touch electrode TE changes according to the shape of the touch electrode to which the touch signal is provided.

[0152] In this case, the size of the touch electrode TE provided on the display panel 110 can correspond to the size of one sub-pixel or the size of two or more sub-pixels. In addition, each touch electrode TE can be of a flat type without an opening, or can be of a mesh type having one or more openings.

[0153] If a touch electrode TE is of a mesh type and its size corresponds to the size of two or more sub-pixels, then a touch electrode TE has two or more openings, and the position and size of each of the two or more openings respectively correspond to the position and size of the light-emitting area of the sub-pixel.

[0154] In this case, the display panel 110 may be a split-type display panel in which each of a plurality of touch electrodes TE of the same size is separated from each other; or may be a woven-type display panel in which touch electrodes TE of different sizes are arranged in adjacent rows or columns.

[0155] The touch display device 100 of the present disclosure may have common voltage feedback lines FL of different shapes for detecting distortion of the common voltage Vcom according to the structure of the touch electrodes TE.

[0156] Since the structure of the touch electrode TE illustrated above corresponds to the split-type touch electrode TE, the structure of the woven-type touch electrode will be further described below.

[0157] Figure 9 A display panel having a woven-type touch electrode in a touch display device according to an embodiment of the present disclosure is shown.

[0158] Reference Figure 9 , the woven-type display panel 110 of the touch display device 100 according to an embodiment of the present disclosure may include a plurality of touch electrode groups TEG, each touch electrode group including four long touch electrodes TE1_L - TE4_L and four groups of short touch electrodes.

[0159] In other words, each of the long touch electrodes TE1_L, TE2_L, TE3_L, TE4_L having a longer length in the row direction may correspond to the total length of four short touch electrodes TE(1)1_S, TE(1)2_S, TE(1)3_S, TE(1)4_S. In this case, four short touch electrodes (for example, TE(1)1_S, TE(2)1_S, TE(3)1_S, TE(4)1_S) in the column direction may be connected to one short touch line (for example, TL1_S). Therefore, four short touch electrodes arranged in the column direction may form a short touch electrode block connected by the same line. And, the four long touch electrodes and the short touch electrode block connected by the same line corresponding thereto may form a touch electrode group TEG.

[0160] For the woven-type 4X4 touch electrode structure, the number of short touch electrodes in the row in which short touch electrodes are arranged among two adjacent rows is 1 / 4 of the number of long touch electrodes in the row in which long touch electrodes are arranged. Accordingly, each length of the long touch electrodes TE1_L, TE2_L, TE3_L, TE4_L is approximately four times that of the short touch electrodes.

[0161] In this case, the woven 4X4 touch electrode structure includes four long touch electrodes TE1_L, TE2_L, TE3_L, TE4_L and sixteen short touch electrodes TE(1)1_S, TE(1)2_S, TE(1)3_S, TE(1)4_S ~ TE(4)1_S, TE(4)2_S, TE(4)3_S, TE(4)4_S. However, four short touch electrodes (such as TE(1)1_S, TE(2)1_S, TE(3)1_S, TE(4)1_S) in the column direction are connected to a short touch line (such as TL1_S).

[0162] Therefore, the four short touch electrodes (such as TE(1)1_S, TE(2)1_S, TE(3)1_S, TE(4)1_S) connected to the short touch line (such as TL1_S) form a short touch electrode block connected by the same line, and the sixteen short touch electrodes TE(1)1_S, TE(1)2_S, TE(1)3_S, TE(1)4_S ~ TE(4)1_S, TE(4)2_S, TE(4)3_S, TE(4)4_S form four short touch electrode blocks respectively connected by the same line.

[0163] As a result, each of the long touch lines TL1_L, TL2_L, TL3_L, TL4L is connected to four long touch electrodes TE1_L, TE2_L, TE3_L, TE4_L respectively, and each of the four short touch electrode blocks is connected to the short touch lines TL1_S, TL2_S, TL3_S, TL4_S respectively. Therefore, for the woven 4X4 touch electrode structure, eight touch lines TL1_L, TL2_L, TL3_L, TL4L, TL1_S, TL2_S, TL3_S, TL4_S and eight touch channels are required.

[0164] Accordingly, compared with the split touch electrode structure, the woven touch electrode structure has the effect of reducing the number of touch lines and touch channels.

[0165] On the other hand, the size of the touch electrode group TEG may vary, but the size of the touch electrode group TEG can be determined considering the distance between fingers or a stylus, thereby effectively arranging the touch electrodes TE on the display panel 110 and improving the multi-touch detection accuracy.

[0166] On the other hand, in the display panel 110, a plurality of woven-type touch electrode groups TEG can be provided in the horizontal and vertical directions. In this case, the active regions of the display images in the display panel 110 for each touch electrode group TEG are electrically separated, but in the non-active regions where no image is displayed in the display panel 110, they can be connected to the touch driving circuit 160 through the touch lines TL.

[0167] As described above, for the woven type in which touch electrodes of different sizes are provided in adjacent rows (or columns), the distortion of the common voltage Vcom in the gate line GL extending along the long touch electrode may be different from the distortion of the common voltage Vcom in the gate line GL extending along the short touch electrode.

[0168] Therefore, for the woven type in which touch electrodes TE of different sizes are arranged in adjacent rows (or columns), the structure of the common voltage feedback line FL for detecting the distorted common voltage Vcom can be changed by mirroring the structure of the touch electrode TE overlapping with the gate line GL.

[0169] Figure 10 An exemplary structure of the common voltage feedback line formed by mirroring the structure of the touch electrode overlapping with the gate line in the touch display device according to an embodiment of the present disclosure is shown.

[0170] Reference Figure 10 , the touch electrodes TE of the display panel 110 in the touch display device 100 according to an embodiment of the present disclosure can be of the woven type in which touch electrodes of different sizes are arranged in adjacent rows (or columns).

[0171] As an example, long touch electrodes TE1_L, TE2_L, TE3_L, TE4_L having a longer length in the row direction can correspond to the total length of four short touch electrodes TE(1)1_S, TE(1)2_S, TE(1)3_S, TE(1)4_S.

[0172] In this case, the number of short touch electrodes (e.g., TE(1)1_S, TE(1)2_S, TE(1)3_S, TE(1)4_S) in one row is 1 / 4 of the number of adjacent long touch electrodes (e.g., TE1_L). Correspondingly, the length L2 of the long touch electrode TE1_L is approximately four times the length L1 of each short touch electrode TE(1)1_S - TE(1)4_S.

[0173] As an example, for the parasitic capacitance Cgc formed between the gate line GL2 and the first short touch electrode TE(1)1_S in the region where the first short touch electrode TE(1)1_S overlaps with the adjacent gate line GL2, the parasitic capacitance Cgc formed between the gate line GL1 and the first long touch electrode TE1_L in the region where the first long touch electrode TE1_L overlaps is approximately four times that value.

[0174] At this time, the common voltage feedback line FL can have the following structure: the width W2 of the common voltage feedback line FL for detecting the common voltage Vcom overlapping with the first gate line GL1 can be set to be approximately four times the width W1 of the common voltage feedback line FL overlapping with the second gate line GL2.

[0175] That is to say, in the non-display area, the width ratio of the common voltage feedback line FL overlapping with the gate line GL can be changed according to the length ratio (e.g., 1:4) of the adjacent long touch electrode (e.g., TE1_L) and the short touch electrode (e.g., TE(1)1_S) in a touch electrode group (TEG).

[0176] In other words, the widths (W1 and W2) of the common voltage feedback line FL overlapping with the gate line GL can be proportional to the lengths (L1 or L2) of the gate line GL overlapping with the touch electrode TE.

[0177] For example, the ratio L1 / L2 of the length L2 of the first gate line GL1 overlapping with the long touch electrode TE1_L and the length L1 of the second gate line GL2 overlapping with the short touch electrodes TE(1)1_S - TE(1)4_S can be equal to the ratio W1 / W2 of the width W2 of the common voltage feedback line FL overlapping with the first gate line GL1 and the width W1 of the common voltage feedback line FL overlapping with the second gate line GL2.

[0178] However, even if the design structure is the same, the length ratio L1 / L2 of the gate line GL overlapping with the touch electrode TE and the width ratio W1 / W2 of the gate line GL overlapping with the common voltage feedback line FL may deviate due to errors or offsets within a certain percentage error range in the manufacturing process.

[0179] At the same time, one or more gate lines GL may overlap with the long touch electrodes TE1_L - TE4_L or the short touch electrodes TE(1)1_S - TE(3)4_S. Accordingly, the value of the width (e.g., W1 or W2) of the common voltage feedback line FL can correspond to the thickness of the long touch electrodes TE1_L - TE4_L or the short touch electrodes TE(1)1_S - TE(3)4_S overlapping with the gate line GL and overlap with all corresponding gate lines GL simultaneously.

[0180] As described above, the touch display device 100 can change the width of the overlap between the common voltage feedback line GL and the gate line GL according to the length of the overlap between the touch electrode and the gate line GL, thereby detecting a feedback capacitance proportional to the parasitic capacitance formed between the gate line GL and the touch electrode TE.

[0181] Here, for convenience, as an example, a case is shown in which each of the gate lines GL1 - GL6 is disposed on each of the long touch electrodes TE1_L - TE3_L and the short touch electrodes TE(1)1_S - TE(3)4_S in the row direction. However, multiple gate lines GL can also be disposed on each of the long touch electrodes TE1_L - TE3_L and the short touch electrodes TE(1)1_S - TE(3)4_S.

[0182] At this time, in the non - display area where the gate line GL extends, a common voltage feedback line FL can be disposed along a direction intersecting the gate line GL, and the width (W1 or W2) of the overlap of the common voltage feedback line with the gate line GL is proportional to the length (L1 or L2) of the overlap between the gate line GL and the touch electrode TE.

[0183] When the gate line GL1 is orthogonal to the touch line TL, the common voltage feedback line FL can be disposed parallel to the touch line TL in the non - display area.

[0184] In this case, the non - display area where the common voltage feedback line FL is disposed can be an area opposite to the gate driving circuit 120 based on the display area AA.

[0185] Accordingly, by detecting the parasitic capacitance Cgc between the gate line GL and the touch electrode TE by means of the feedback capacitance Cfb formed in the common voltage feedback line FL, a compensation common voltage Vcom_comp capable of canceling the distorted waveform of the common voltage Vcom can be generated.

[0186] For the above - mentioned purpose, the common voltage feedback line FL can be connected to the common voltage compensation circuit 162 by extending along the non - display area. The common voltage compensation circuit 162 can generate a compensation common voltage Vcom_comp capable of canceling the distorted waveform of the common voltage Vcom detected through the common voltage feedback line FL, and can provide the compensation common voltage Vcom_comp through the touch line TL.

[0187] The common voltage compensation circuit 162 can be located inside the touch driving circuit 160, or can be located outside the touch driving circuit 160.

[0188] As described above, when a parasitic capacitance Cgc is formed between the gate line GL and the touch electrode TE due to the scan signal SCAN provided through the gate line GL, resulting in distortion of the common voltage Vcom, the touch display device 100 of the present disclosure detects the distortion of the common voltage Vcom through the common voltage feedback line FL and provides a compensated common voltage capable of compensating for the distorted common voltage Vcom, thereby preventing image errors caused by the distortion of the common voltage Vcom.

[0189] The above description has been presented for the purpose of enabling those skilled in the art to implement and use the technical idea of the present invention, and has been provided in the context of a specific application and its requirements. Various modifications, supplements, and substitutions to the described embodiments will be apparent to those skilled in the art without departing from the essence and scope of the present invention, and the general principles defined herein can also be applied to other embodiments and applications. The above description and drawings have provided examples of the technical idea of the present invention for illustrative purposes only. That is, the disclosed embodiments are intended to illustrate the scope of the technical idea of the present invention. Therefore, the scope of the present invention is not limited to the disclosed embodiments, but rather conforms to the broadest scope consistent with the claims. The scope of protection of the present invention should be interpreted based on the appended claims, and all technical ideas within the equivalent scope thereof should be interpreted as being included within the scope of the present invention.

Claims

1. A touch display device, comprising: a display panel including a plurality of touch electrodes disposed in a display area for displaying an image, the plurality of touch electrodes being electrically connected to a plurality of touch lines, the plurality of touch lines extending in a first direction; a gate driving circuit for providing a scanning signal to the display panel through a plurality of gate lines extending in a second direction, the second direction being different from the first direction; a touch driving circuit for sensing a touch by detecting a touch signal from the plurality of touch electrodes during a touch driving period, and for displaying an image by providing a common voltage to the plurality of touch electrodes through the plurality of touch lines during a display driving period; a common voltage feedback line disposed in a non-display area of the display panel along a direction intersecting the plurality of gate lines and overlapping with the plurality of gate lines in the non-display area of the display panel; and a common voltage compensation circuit for detecting a feedback capacitance formed in the common voltage feedback line and providing a compensation common voltage generated based on the feedback capacitance through the plurality of touch lines, wherein the plurality of touch electrodes include a first touch electrode having a first length in the second direction and a second touch electrode having a second length greater than the first length in the second direction, the plurality of gate lines include a first gate line overlapping with the first touch electrode and a second gate line overlapping with the second touch electrode, a first portion of the common voltage feedback line overlaps with the first gate line and has a first width, and a second portion of the common voltage feedback line overlaps with the second gate line and has a second width greater than the first width.

2. The touch display device according to claim 1, wherein the plurality of touch electrodes are split-type touch electrodes, and at least two of the plurality of touch electrodes have the same size.

3. The touch display device according to claim 1, wherein the plurality of touch electrodes are braided-type touch electrodes, wherein a plurality of first touch electrodes having the first length in the second direction and a plurality of second touch electrodes having the second length in the second direction are alternately arranged along the first direction, and at least a part of the plurality of first touch electrodes arranged along the first direction is connected to one of the plurality of touch lines.

4. The touch display device according to claim 1, wherein the common voltage feedback line overlapping with the plurality of gate lines is arranged along the first direction such that the display area is located between the gate driving circuit and the common voltage feedback line.

5. The touch display device according to claim 1, wherein a ratio of the first width to the second width is equal to a ratio of the first length to the second length.

6. The touch display device according to claim 1, wherein the compensation common voltage is a signal for canceling a common voltage distortion caused by a parasitic capacitance generated due to an overlap of the scanning signals supplied through adjacent gate lines among the plurality of gate lines.

7. A touch driving circuit, comprising: A plurality of touch lines extending in one direction and configured to transmit touch signals to a display panel including a plurality of touch electrodes and a plurality of gate lines; A touch sensing circuit that, during a touch driving period, provides touch driving signals to the plurality of touch electrodes via the plurality of touch lines and receives touch sensing signals from the plurality of touch electrodes, and during a display driving period, supplies a common voltage to the plurality of touch electrodes via the plurality of touch lines; A touch controller that detects the presence of a touch in response to the touch sensing signals and calculates touch coordinates based on the touch sensing signals; A common voltage feedback line disposed to overlap the plurality of gate lines along a direction intersecting the plurality of gate lines; And A common voltage compensation circuit configured to detect a feedback capacitance formed in the common voltage feedback line and provide a compensated common voltage generated based on the feedback capacitance via the plurality of touch lines, wherein the plurality of touch electrodes include a first touch electrode having a first length and a second touch electrode having a second length greater than the first length, the plurality of gate lines include a first gate line overlapping the first touch electrode and a second gate line overlapping the second touch electrode, a first portion of the common voltage feedback line overlaps the first gate line and has a first width, and a second portion of the common voltage feedback line overlaps the second gate line and has a second width greater than the first width.

8. The touch driving circuit according to claim 7, wherein the compensated common voltage is a signal for canceling a common voltage distortion caused by a parasitic capacitance generated due to overlapping of scan signals supplied through adjacent gate lines among the plurality of gate lines.

9. A display panel, comprising: A plurality of touch electrodes, each of the plurality of touch electrodes corresponding to a plurality of sub-pixels respectively; A plurality of touch lines extending in a first direction and configured to transmit touch signals to the plurality of touch electrodes; A plurality of gate lines extending in a second direction different from the first direction and configured to transmit scan signals to the plurality of sub-pixels; And A common voltage feedback line disposed to overlap the plurality of gate lines along a direction intersecting the plurality of gate lines in a non-display area, wherein the plurality of touch electrodes include a first touch electrode having a first length in the second direction and a second touch electrode having a second length greater than the first length in the second direction, the plurality of gate lines include a first gate line overlapping the first touch electrode and a second gate line overlapping the second touch electrode, a first portion of the common voltage feedback line overlaps the first gate line and has a first width, and a second portion of the common voltage feedback line overlaps the second gate line and has a second width greater than the first width.

10. The display panel according to claim 9, wherein the common voltage feedback line overlapping the plurality of gate lines is arranged along the first direction such that the display area is located between the common voltage feedback line and the gate driving circuit for providing the scan signal.

Images