Touch display device, touch driving circuit thereof, and touch driving method

Abstract

Embodiments of the present disclosure relate to a touch display device, a touch drive circuit and a touch drive method thereof, and more specifically to a touch display device, a touch drive circuit and a touch drive method thereof that can reduce the distortion phenomenon of a common voltage caused by a load of a touch electrode. In addition, embodiments of the present disclosure relate to a touch display device, a touch drive circuit and a touch drive method thereof that can effectively reduce the distortion phenomenon of a common voltage according to the structure of a touch electrode. In addition, embodiments of the present disclosure relate to a touch display device, a touch drive circuit and a touch drive method thereof that can reduce the distortion phenomenon of a common voltage generated during a driving process in which a display drive operation and a touch drive operation are alternately driven.

Description

[0001] Cross - reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10 - 2020 - 0182548, filed on December 23, 2020, which is incorporated herein by reference for all purposes as if fully set forth herein. Technical field

[0003] An embodiment relates to a touch display device, a touch driving circuit thereof, and a touch driving method. Background art

[0004] With the development of multimedia, the importance of flat - panel display devices is constantly increasing. In response, flat - panel display devices such as liquid crystal displays (LCDs), plasma display panels (PDPs), and organic light - emitting displays (OLEDs) have been commercialized.

[0005] In addition, touch display devices are widely used, in which a touch panel is stacked on such a display device. By utilizing the characteristic that the electrical properties (e.g., resistance or capacitance) at the touch point where a hand or a stylus touches change, the touch panel generates information corresponding to the touch point through sensing of the touch point or performs calculations regarding touch operations.

[0006] Such a touch display device is one of user interfaces, and its applications are extended to small portable terminals, office devices, mobile devices, and so on.

[0007] However, when a touch panel is separately stacked on a touch display device, the display device becomes thick. Therefore, there are limitations in making the display device thin, the light - transmission efficiency is reduced due to passing through the stacked touch panel, and the manufacturing cost increases. To solve these problems, recently, an advanced in - cell touch (AIT) type display device has been proposed, in which touch electrodes are embedded in the pixel regions of a display panel.

[0008] Meanwhile, as the size and resolution of a touch display device increase, the load of the touch electrodes provided in the display panel increases. Therefore, due to the distortion phenomenon of the common voltage supplied to the touch electrodes, errors may occur in the image displayed on the display panel. Summary of the invention

[0009] An embodiment can provide a touch display device, a touch driving circuit thereof, and a touch driving method capable of reducing the distortion phenomenon of a common voltage caused by the load of touch electrodes.

[0010] In addition, embodiments may provide a touch display device, a touch driving circuit thereof, and a touch driving method that can effectively reduce the distortion phenomenon of a common voltage according to the structure of touch electrodes.

[0011] In addition, embodiments may provide a touch display device, a touch driving circuit thereof, and a touch driving method that can reduce the distortion phenomenon of a common voltage generated during an alternating driving process of a display driving operation and a touch driving operation.

[0012] According to one aspect, embodiments may provide a touch display device including: a display panel including a plurality of touch electrodes; a display driving circuit that provides a scanning signal to the display panel through a plurality of gate lines; and a touch driving circuit that performs a touch sensing operation according to capacitance changes of the plurality of touch electrodes and provides at least one of compensated common voltages based on the structure and shape of the plurality of touch electrodes to the display panel to cancel the distortion of the common voltage during an overlapping period of the scanning signal and / or during a transition period between a display driving period and a touch driving period.

[0013] According to one aspect, the plurality of touch electrodes are split type touch electrodes spaced apart from each other at equal intervals.

[0014] According to one aspect, the plurality of touch electrodes are woven type touch electrodes, in which a plurality of long touch electrodes having a longer length in a first direction and a plurality of short touch electrodes having a shorter length are alternately arranged in a second direction, and the plurality of short touch electrodes arranged in the second direction are connected to the same touch line.

[0015] According to one aspect, at least one of the compensated common voltages has different waveforms provided to the long touch electrodes and the short touch electrodes.

[0016] According to one aspect, in a case of canceling the distortion of the common voltage during an overlapping period of the scanning signal, at least one of the compensated common voltages is a pulse signal having a first level selected in a high level portion higher than an average level of the distorted common voltage, a second level corresponding to the average level of the distorted common voltage, and a third level selected in a low level portion lower than the average level of the distorted common voltage.

[0017] According to one aspect, in a case of canceling the distortion of the common voltage during a transition period, at least one of the compensated common voltages is a single-level signal having a constant level.

[0018] According to one aspect, at least one of the compensated common voltages is provided during a display driving period before entering a touch driving period and during a display driving period after the touch driving period ends.

[0019] According to one aspect, an embodiment may provide a touch display device, which further includes a compensated common voltage generation circuit. The compensated common voltage generation circuit includes: a first multiplexer that receives a first-level voltage and a second-level voltage as input signals and selects an output signal according to a first control signal; a second multiplexer that receives the output signal of the first multiplexer and a third-level voltage as input signals and selects an output signal according to a second control signal; and a buffer circuit that receives the output signal of the second multiplexer and transmits at least one of the compensated common voltages.

[0020] According to one aspect, an embodiment may provide a touch display device, which further includes a compensated common voltage generation circuit. The compensated common voltage generation circuit includes: a multiplexer that receives a first-level voltage, a second-level voltage, and a third-level voltage as input signals and selects an output signal according to a first control signal and a second control signal; and a buffer circuit that receives the output signal of the multiplexer and transmits at least one of the compensated common voltages.

[0021] According to one aspect, an embodiment may provide a touch display device, which further includes a plurality of common voltage compensation lines. The plurality of common voltage compensation lines are arranged in parallel with a plurality of touch lines that transmit touch signals to the plurality of touch electrodes, and are configured to provide at least one of the compensated common voltages to the plurality of touch electrodes.

[0022] According to another aspect, an embodiment may provide a touch driving circuit, including: a plurality of touch lines that transmit touch signals to a display panel including a plurality of touch electrodes; a touch sensing circuit that provides touch driving signals to the plurality of touch electrodes through the plurality of touch lines and receives touch sensing signals from the plurality of touch electrodes; a touch controller that detects the presence of a touch and calculates a touch coordinate according to the touch sensing signals; and a compensated common voltage generation circuit that is configured to generate at least one of the compensated common voltages to be provided to the display panel according to the structure and shape of the plurality of touch electrodes, so as to offset the distortion of the common voltage during an overlapping period of the scan signals provided to the display panel and / or during a transition period between a display driving period and a touch driving period.

[0023] According to another aspect, an embodiment may provide a touch driving method for a touch display device, the touch display device including: a display driving circuit that provides a scanning signal to a display panel having a plurality of touch electrodes; and a touch driving circuit that provides a touch driving signal to the display panel and senses a touch based on a touch sensing signal received in response to the touch driving signal, the touch driving method including: detecting an overlapping distortion of a common voltage during an overlapping period of the scanning signal; detecting a transition distortion of the common voltage during a transition period between a display driving period and a touch driving period; generating at least one compensated common voltage according to the structure and shape of the plurality of touch electrodes to offset the overlapping distortion of the common voltage and / or the transition distortion of the common voltage; and providing at least one of the compensated common voltages to corresponding touch electrodes during the overlapping period of the scanning signal and / or during the transition period between the display driving period and the touch driving period.

[0024] According to an exemplary embodiment, a touch display device, a touch driving circuit thereof, and a touch driving method capable of reducing a distortion phenomenon of a common voltage caused by a load of a touch electrode may be provided.

[0025] According to an exemplary embodiment, a touch display device, a touch driving circuit thereof, and a touch driving method capable of effectively reducing a distortion phenomenon of a common voltage according to a structure of a touch electrode may be provided.

[0026] According to an exemplary embodiment, a touch display device, a touch driving circuit thereof, and a touch driving method capable of reducing a distortion phenomenon of a common voltage generated during a driving process in which a display driving operation and a touch driving operation alternate may be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] According to the following detailed description in conjunction with the accompanying drawings, the above and other objects, features, and advantages of the present disclosure will be more clearly understood. In the drawings:

[0028] Figure 1 A diagram schematically showing a touch display device according to an embodiment;

[0029] Figure 2 A timing chart showing timings for configuring a display driving period and a touch driving period in a touch display device according to an embodiment of the present disclosure;

[0030] Figure 3 A timing signal showing an LHB (long horizontal blank) driving operation in a touch display device according to an embodiment of the present disclosure;

[0031] Figure 4Shows a part of a touch electrode region in a touch display device according to an embodiment of the present invention;

[0032] Figure 5 Shows a graph of the distortion of the common voltage that occurs between the gate line and the touch electrode according to the driving period in a touch display device according to an embodiment of the present disclosure;

[0033] Figure 6 Shows a schematic diagram showing an overlap distortion phenomenon caused by the overlap of scan signals during the display driving period in a touch display device according to an embodiment of the present disclosure;

[0034] Figure 7 Shows a display panel including a split-type touch electrode in a touch display device according to an embodiment of the present disclosure;

[0035] Figure 8 Shows the signal waveform of the distortion of the common voltage generated in the split-type touch electrode and the signal waveform of the compensated common voltage in a touch display device according to an embodiment of the present disclosure;

[0036] Figure 9 Shows a display panel having a woven-type touch electrode in a touch display device according to an embodiment of the present disclosure;

[0037] Figure 10 Shows a signal waveform showing an example of the distortion of the common voltage generated in the woven-type long touch electrode and the compensated common voltage in a touch display device according to an embodiment of the present disclosure;

[0038] Figure 11 Shows a signal waveform showing an example of the distortion of the common voltage generated in the woven-type short touch electrode and the compensated common voltage in a touch display device according to an embodiment of the present disclosure;

[0039] Figure 12 Shows a signal waveform showing an example of the compensated common voltage provided during the transition period between the display driving period and the touch driving period in a touch display device according to an embodiment of the present disclosure;

[0040] Figure 13 Shows an exemplary structure of a touch electrode including a common voltage compensation line in a touch display device according to an embodiment of the present disclosure;

[0041] Figure 14 Shows an exemplary block diagram of a circuit for generating a compensated common voltage in a touch display device according to an embodiment of the present disclosure;

[0042] Figure 15Another exemplary block diagram of a circuit for generating a compensated common voltage in a touch display device according to an embodiment of the present disclosure is shown. Detailed implementation

[0043] In the following description of examples or embodiments of the present invention, reference will be made to the accompanying drawings, in which specific examples or embodiments that can be implemented are shown by way of illustration, and in the drawings, the same reference numerals and symbols may be used to represent the same or similar components, even when they are shown in different drawings from each other. In addition, in the following description of examples or embodiments of the present invention, when it is determined that a detailed description of well-known functions and components included herein may make the subject matter in some embodiments of the present invention unclear, the detailed description will be omitted. Terms such as "including", "having", "containing", "constituting", "consisting of", and "formed of" used herein generally intend to allow the addition of other components, unless these terms are used together with the term "only". As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form.

[0044] Terms such as "first", "second", "A", "B", "(A)", or "(B)" may be used herein to describe elements of the present invention. Each of these terms is not used to define the essence, order, sequence, quantity, etc. of the element, but is only used to distinguish the corresponding element from other elements.

[0045] When it is mentioned that a first element is "connected or coupled" to a second element, "in contact or overlaps" with the second element, etc., it should be interpreted that the first element can not only be "directly connected or coupled" to the second element or "directly in contact or overlap" with the second element, but also a third element can be "inserted" between the first element and the second element, or the first element and the second element can be "connected or coupled", "in contact or overlap" with each other through a fourth element, etc. Here, the second element may be included in at least one of two or more elements that are "connected or coupled", "in contact or overlap" with each other, etc.

[0046] When using time-related terms such as "after", "subsequently", "then", "before", etc. to describe a process or operation for an element or structure, or a flow or step in an operation method, a processing method, or a manufacturing method, these terms may be used to describe a non-continuous or non-sequential process or operation, unless the terms "directly" or "immediately" are also used together.

[0047] In addition, when referring to any dimensions, relative sizes, etc., numerical values or corresponding information of components or features (e.g., levels, ranges, etc.) should be considered, including tolerances or error ranges that may be caused by various factors (e.g., process factors, internal or external influences, noise, etc.), even when the relevant description is not specified. In addition, the term "may" fully encompasses all the meanings of the term "can".

[0048] Figure 1 A diagram schematically showing a touch display device according to an embodiment.

[0049] Referring to Figure 1 , the touch display device 100 according to an embodiment may have a function of displaying an image and a function of sensing a touch from a user.

[0050] In order to implement the function of displaying an image and the function of sensing a touch simultaneously, the touch display device 100 may include a display panel 110 in which a plurality of data lines and a plurality of gate lines are arranged, a display driving circuit 120 for driving the display panel 110, and so on.

[0051] Functionally speaking, the display driving circuit 120 may include a data driving circuit for driving the data lines, a gate driving circuit for driving the gate lines, and a controller for controlling the data driving circuit and the gate driving circuit. The display driving circuit 120 may be implemented as one or more integrated circuits.

[0052] The touch display device 100 may include a touch screen panel TSP in which a plurality of touch electrodes TE for sensing a touch are arranged, and a touch driving circuit 130 for driving the touch screen panel TSP and processing signals related to the touch.

[0053] The touch screen panel TSP in the touch display device 100 may be an external type, in which the touch screen panel TSP is manufactured separately from the display panel 110 and then bonded to the display panel 110, or the touch screen panel TSP in the touch display device 100 may be an embedded type, in which the touch screen panel TSP is manufactured together with the display panel 110 and the touch screen panel TSP is located inside the display panel 110.

[0054] Therefore, the touch screen panel TSP in the touch display device 100 according to an embodiment may be an independent panel having a function of sensing a touch, or a display panel 110 having a display function and a function of sensing a touch. Hereinafter, for ease of description, it is assumed that the display panel 110 includes the touch screen panel TSP.

[0055] The touch driving circuit 130 can provide a touch driving signal to the display panel 110 to drive the display panel 110, receive a touch sensing signal from the display panel 110, and detect the presence of a touch or the touch coordinates based on the touch sensing signal.

[0056] The touch driving circuit 130 can include a touch sensing circuit for providing the touch driving signal and receiving the touch sensing signal, and a touch controller for detecting the presence of a touch or calculating the touch coordinates.

[0057] The touch driving circuit 130 can be implemented as one or more components, such as an integrated circuit, or implemented separately from the display driving circuit 120.

[0058] In addition, all or at least a part of the touch driving circuit 130 can be implemented by integrating with the display driving circuit 120 or the internal circuit of the display driving circuit 120. For example, the touch sensing circuit of the touch driving circuit 130 can be implemented as a circuit integrated with the data driving circuit of the display driving circuit 120.

[0059] In addition, the touch display device 100 can include a micro control unit 150 for controlling the touch driving circuit 130.

[0060] The micro control unit 150 can generate a touch synchronization signal Tsync for controlling the touch driving circuit 130 based on a control synchronization signal Csync received from a timing controller (TCON) 140. The micro control unit 150 provides and receives touch signals based on an interface defined with the touch driving circuit 130.

[0061] Here, the micro control unit 150 can be formed in an integrated circuit together with the touch controller in the touch driving circuit 130, or can be formed in an integrated circuit together with the timing controller 140.

[0062] In addition, the touch display device 100 can include a timing controller 140 for controlling the display driving circuit 120 and the micro control unit 150.

[0063] The timing controller 140 receives timing signals from a host system (not shown), such as a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, a main clock, and digital image data DATA.

[0064] The timing controller 140 controls the scanning timing of the display driving circuit 120 based on scanning timing control signals including a gate start pulse, a gate shift clock, and a gate output enable signal. In addition, the timing controller 140 controls the data timing of the display driving circuit 120 based on data timing control signals including a source sampling clock and a source output enable signal.

[0065] Meanwhile, the touch display device 100 can sense the presence of a touch or touch coordinates based on the capacitance formed by the touch electrodes TE.

[0066] The touch display device 100 can sense a touch through a mutual-capacitance scheme or a self-capacitance scheme, which are capacitance-based touch sensing schemes.

[0067] In the case of a mutual-capacitance-based touch sensing scheme, a plurality of touch electrodes TE can be classified into touch driving electrodes that are provided with a touch driving signal through a touch driving line, and touch sensing electrodes that form a capacitance with the touch driving electrodes and provide a touch sensing signal through a touch sensing line. Here, the touch driving line and the touch sensing line can be referred to as touch lines.

[0068] In the case of a mutual-capacitance-based touch sensing scheme, the presence of a touch and touch coordinates can be detected based on a change in the mutual capacitance formed between the touch driving electrode and the touch sensing electrode according to the presence of an indicator (e.g., a finger, a pen, etc.).

[0069] In the case of a self-capacitance-based touch sensing scheme, each touch electrode TE serves as both a touch driving electrode and a touch sensing electrode. That is, a touch driving signal is provided to the touch electrode TE through a touch line, and the touch sensing signal generated in the touch electrode TE provided with the touch driving signal is transmitted through the same touch line. Therefore, in the case of a self-capacitance-based touch sensing scheme, there is no distinction between the touch driving electrode and the touch sensing electrode, and there is no distinction between the touch driving line and the touch sensing line.

[0070] In the case of a self-capacitance-based touch sensing scheme, the presence of a touch and touch coordinates can be detected based on a change in the capacitance formed between an indicator such as a finger or a pen and the touch electrode TE.

[0071] Therefore, the touch display device 100 can sense a touch through a mutual-capacitance-based touch sensing scheme or a self-capacitance-based touch sensing scheme.

[0072] In addition, 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, a quantum dot display device, etc.

[0073] For example, when the touch display device 100 according to an embodiment is a liquid crystal display device, a plurality of touch electrodes TE can be arranged on the display panel 110, and the plurality of touch electrodes TE can be common electrodes to which a common voltage for displaying an image is applied.

[0074] In another example, when the touch display device 100 is an organic light-emitting display device, the touch display device 100 may include an organic light-emitting diode composed of a first electrode (anode electrode), an organic light-emitting layer, and a second electrode (cathode electrode), a packaging layer located on 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 may be formed on the touch sensor metal layer, or may be formed on the second electrode constituting the cathode electrode of the organic light-emitting diode.

[0075] Meanwhile, when changing the level of the data voltage supplied to the display panel 110 during the display driving period, the common voltage supplied to the common electrode or the touch electrode TE may be a DC voltage having a specific voltage level during a predetermined time.

[0076] Figure 2 The timing for configuring the display driving period and the touch driving period in the touch display device according to an embodiment of the present disclosure is shown.

[0077] Referring to Figure 2 According to an embodiment of the present disclosure, the touch display device 100 performs display driving for displaying an image during a predetermined display driving period DP within the display frame period, and performs touch driving for sensing a touch input from a finger or a stylus during a predetermined touch driving period TP within the display frame period.

[0078] The touch display device 100 uses the common electrode for driving each pixel as the electrode for sensing touch. Therefore, during the display driving period DP, a common voltage is supplied to the thin film transistor connected to the common electrode, and during the touch driving period TP, a touch driving signal is supplied to the common electrode serving as the touch electrode.

[0079] The display driving period DP and the touch driving period TP may be equal in time, may overlap with each other entirely or partially in time, or may be separated from each other in time.

[0080] The driving method in which the display driving period DP and the touch driving period TP are separated from each other in time may be referred to as time-division driving.

[0081] 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 may be performed simultaneously. This driving method may be referred to as a time-free driving operation.

[0082] In time-division driving, the display driving period DP and the touch driving period TP may be arranged alternately.

[0083] Therefore, when the display driving period DP and the touch driving period TP are separated in time and alternately arranged simultaneously, the touch driving period TP can correspond to a blank period Blank during which the display driving operation is not performed.

[0084] The touch display device 100 can generate a touch synchronization signal Tsync that swings between a high level and a low level, and the display driving period DP and the touch driving period TP can be identified or controlled through the touch synchronization signal Tsync. That is, the touch synchronization signal Tsync can be a driving timing control signal for defining the touch driving period TP.

[0085] 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.

[0086] In this case, the touch driving circuit 130 can provide a touch driving signal to the touch electrode TE during the touch driving period TP when the touch synchronization signal 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.

[0087] Meanwhile, regarding the method of allocating the display driving period DP and the touch driving period TP in one display frame period, for example, one display frame period can be divided into a display driving period DP and a touch driving period TP, and the display driving operation can be performed during one display driving period DP, and the touch driving operation for sensing touch inputs from a finger and a stylus can be performed during one touch driving period TP corresponding to the blank period Blank.

[0088] The touch display device 100 performs the touch driving operation once during a screen refresh period or a display frame period corresponding to the frame frequency.

[0089] For example, when the frame frequency is 60 Hz, the display driving operation is performed to turn on or off the pixels constituting the display panel 110 through N gate lines within a horizontal period of 1 / 60 s. After that, the touch driving period TP for the touch sensing operation is performed at a predetermined interval. In this case, the touch reporting rate will be 60 Hz.

[0090] In another example, a display frame period can be divided into two or more display driving periods DP and two or more touch driving periods TP, and a display driving operation can be performed during two or more display driving periods DP in one display frame period, and a touch driving operation for sensing touch input from a finger and a stylus on all or at least a part of a display screen once or twice or more times can be performed during two or more touch driving periods TP in one display frame period.

[0091] As described above, 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 a display driving operation and a touch driving operation are performed, each of the two or more blank periods corresponding to the two or more touch driving periods TP in one display frame period is sometimes referred to as a long horizontal blank ("LHB").

[0092] Accordingly, two or more periods for sensing a touch from a stylus or a finger in a display frame period can be referred to as LHBs or touch driving periods TP, and a touch driving operation performed during two or more LHBs in one touch frame period is referred to as an "LHB driving operation".

[0093] Figure 3 A timing signal of an LHB driving operation in a touch display device according to an embodiment of the present disclosure is shown.

[0094] Referring to Figure 3 , in a touch display device 100 according to an embodiment of the present disclosure, one display frame period can be temporally divided into 16 display driving periods DP1 - DP16 and 16 touch driving periods TP1 - TP16.

[0095] In this case, the 16 touch driving periods TP1 - TP16 can correspond to 16 long horizontal blanks LHB1 - LHB16.

[0096] In this case, the touch display device 100 divides one display frame period into a plurality of display driving periods DP1 - DP16 and a plurality of touch driving periods TP1 - TP16, and alternately performs a display driving operation and a touch driving operation.

[0097] Alternatively, the touch driving periods TP1 - TP16 can be performed independently of the display driving periods DP1 - DP16.

[0098] Figure 4 A part of a touch electrode area in a touch display device according to an embodiment of the present disclosure is shown.

[0099] Referring to Figure 4 , according to an embodiment of the present disclosure, the touch display device 100 includes a plurality of thin film transistors (TFTs) formed on a substrate, a plurality of pixel electrodes P11-P44 connected to drain nodes or source nodes of the plurality of TFTs, and a touch electrode TE formed to overlap with the plurality of pixel electrodes P11-P44 to form an electric field.

[0100] The gate node of the TFT is connected to a gate line to control the on-off of the TFT according to a scan signal, and the source node or the drain node is connected to a data line DL supplied with a data voltage.

[0101] At this time, when a passive stylus or an active stylus such as a finger touches the display panel 110, the touch display device 100 can recognize a change in capacitance of the touch electrode TE near the contact position of the stylus and detect the touch position. That is, the touch display device 100 can supply a touch driving signal to the touch electrode TE formed on the display panel 110, and then can sense the touch position by detecting a touch sensing signal received from the touch electrode TE and detecting a change in capacitance of each touch electrode TE.

[0102] At this time, a common voltage or a touch driving signal is supplied to the touch electrode TE of the touch display device 100, and thus a parasitic capacitance coupled to the touch electrode TE can be generated. For example, a scan signal supplied to the display panel 110 through a gate line can 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 increases, distortion occurs in the common voltage supplied to the touch electrode TE, and defective lines may appear on the display panel 110.

[0103] Figure 5 A diagram showing distortion of a common voltage occurring between a gate line and a touch electrode according to a driving period in a touch display device according to an embodiment of the present disclosure.

[0104] Referring to Figure 5 , according to an embodiment of the present disclosure, the touch display device 100 can perform a display driving operation for displaying an image during a display driving period DP determined within one display frame period, and perform a touch driving operation for sensing a touch input of a finger or a stylus during a predetermined touch driving period TP.

[0105] In this case, the touch electrode TE for detecting touch can be used as a common electrode for driving each pixel. Therefore, during the display driving period DP, a common voltage can be supplied to the touch electrode (common electrode), and during the touch driving period TP, a touch driving signal can be supplied to the touch electrode (common electrode).

[0106] In this case, the scan signals supplied through the gate lines can overlap within a predetermined period during the display driving period DP. It can accumulate the parasitic capacitance formed between the gate node of the thin film transistor and the touch electrode (common electrode). This parasitic capacitance can increase the load on the touch electrode (common electrode), and may cause defects such as horizontal lines due to the luminance difference caused by the distortion of the common voltage. As described above, the defect caused by the overlap of the scan signals can be referred to as overlap distortion.

[0107] On the other hand, such overlap distortion may occur during the display driving period DP. However, in the case of time free driving in which the display driving operation and the touch driving operation are performed simultaneously, since the scan signal is supplied during the touch driving period TP, it may occur during the touch driving period TP. However, since a DC level common voltage is supplied during the display driving period DP and a pulse-type common voltage (touch driving signal) is supplied during the touch driving period TP, the distortion of the common voltage may be changed.

[0108] Figure 6 The schematic diagram shows the overlap distortion phenomenon caused by the overlap of the scan signals during the display driving period in the touch display device according to an embodiment of the present disclosure.

[0109] Referring to Figure 6 , the touch display device 100 according to an embodiment of the present disclosure can sequentially supply the scan signal SCAN to the display panel 110 through the gate lines at intervals of one horizontal period 1H.

[0110] In this case, the scan signal SCAN can be maintained at a high level during a specific period. Here, as an example, Figure 6 the case where the scan signal SCAN has a high level period of 5 horizontal periods 5H is shown.

[0111] As described above, when the scan signal SCAN (the scan signal SCAN is transmitted to the display panel 110 through the gate line GL) having a predetermined high level period is provided at intervals of a horizontal time period 1H, an overlapping period is generated between adjacent scan signals SCAN. Due to the overlapping period of the scan signal SCAN, a parasitic capacitance Cgc can be generated between the gate line GL and the touch electrode TE. In other words, the parasitic capacitance Cgc may accumulate between the gate node of the thin film transistor TFT and the touch electrode TE supplied with the common voltage Vcom, and the common voltage Vcom may be distorted due to an increase in the load on the touch electrode TE.

[0112] In addition, during the process of entering the touch driving period TP from the display driving period DP, the operation of the gate driving circuit can be temporarily stopped. The operation of the gate driving circuit can be restarted at the start point of the display driving period DP after the touch driving period TP ends. As described above, during the period when the gate driving circuit does not operate continuously, distortion of the common voltage may occur in some gate lines. Therefore, this distortion may cause defects such as horizontal lines due to a difference in brightness. As described above, the defects generated during the transition process between the display driving period and the touch driving period can be referred to as transition distortion.

[0113] The distortion of the common voltage Vcom can vary according to the shape of the touch electrode TE supplied with the touch signal.

[0114] 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. Additionally, each touch electrode TE can be a plate type without an opening or a mesh type having one or more openings.

[0115] If a touch electrode TE is a mesh type and has a size corresponding to the size of two or more sub-pixels, then one touch electrode TE has two or more openings, and the position and size of each of the two or more openings can correspond to the position and size of the light emitting region of the sub-pixel.

[0116] In this case, the display panel 110 can be a split type, in which each of the plurality of touch electrodes TE having the same size is separated from each other, or the display panel 110 can be a woven type, in which touch electrodes TE having different sizes are arranged in adjacent rows or columns.

[0117] By generating a compensated common voltage capable of canceling the distortion of the common voltage Vcom according to the structure of the touch electrode TE and supplying the compensated common voltage to the corresponding touch electrode TE, the touch display device 100 of the present disclosure can reduce the defects caused by the distortion of the common voltage Vcom and improve the image quality.

[0118] Figure 7 A display panel including a split-type touch electrode in a touch display device according to an embodiment of the present disclosure is shown.

[0119] Referring to Figure 7 , when a plurality of split-type touch electrodes TE are provided in the display panel 110 of the touch display device 100 according to an embodiment of the present disclosure, each touch electrode TE among the plurality of touch electrodes TE can be electrically connected to the touch line TL through one or more contact holes CNT.

[0120] The plurality of touch electrodes TE can be located in the active area. Depending on the situation, some of the plurality of touch electrodes TE (for example, the outermost touch electrodes) can be located in the outer area (border area) of the active area, or can extend to the outer area (border area) of the active area. The active area can be an area for displaying an image or performing a touch sensing process.

[0121] The plurality of touch lines TL electrically connected to the plurality of touch electrodes TE can be located in the active area. Depending on the situation, all or some of the plurality of touch lines TL can be located in the outer area of the active area. When the plurality of touch lines TL electrically connected to the plurality of touch electrodes TE are located in the active area, by placing the plurality of touch lines TL in a layer different from the plurality of touch electrodes TE, the plurality of touch lines TL can overlap with the plurality of touch electrodes TE.

[0122] All of the plurality of touch lines TL can have the same or similar length, and can be set from a point connected to the touch driving circuit 130 to an opposite point. The plurality of touch lines TL can be different only at the positions where they are respectively connected to the corresponding touch electrodes TE (i.e., the positions of the contact holes CNT).

[0123] In the case of the split-type display panel 110, if one touch electrode TE is electrically connected to one touch line TL, there should be as many touch lines TL as the number of the plurality of touch electrodes TE. The number of the plurality of touch lines TL can be consistent with the number of touch channels for signal input and output of the touch driving circuit 130.

[0124] Therefore, in the case of the split-type display panel 110 composed of 4×4 touch electrodes TE (wherein 16 touch electrodes TE are arranged in four rows and four columns), there can be 16 touch lines TL and 16 touch channels.

[0125] Figure 8 Shows the signal waveform of the distortion of the common voltage generated in the split-type touch electrodes and the signal waveform of the compensated common voltage in the touch display device according to an embodiment of the present disclosure.

[0126] Referring to Figure 7 , in the touch display device 100 according to an embodiment of the present disclosure, the split-type touch electrodes TE may have the same horizontal length and the same vertical length, and each touch electrode TE may be arranged at equal intervals.

[0127] In this case, even if the distortion of the common voltage Vcom due to the parasitic capacitance Cgc formed between the gate node of the thin film transistor TFT (the gate node is provided with a scan signal) and the touch electrode TE (the touch electrode TE is provided with the common voltage Vcom) may occur due to the overlapping time period between adjacent scan signals SCAN, but since the split-type touch electrodes TE are arranged in the same size, it can also appear in a regular shape.

[0128] Therefore, based on the distortion waveform of the common voltage Vcom generated by the structure of the split-type touch electrodes TE, a compensated common voltage Vcom_comp capable of canceling the distortion can be generated, and the compensated common voltage Vcom_comp is provided to the touch electrode TE. As a result, image defects caused by brightness deviation can be reduced.

[0129] In this case, the compensated common voltage Vcom_comp capable of canceling the distortion of the common voltage Vcom can be formed in the form of pulses having multiple levels. For example, the compensated common voltage Vcom_comp may have a first level voltage V1_comp as a high level composed of a pulse waveform, a second level voltage V2_comp as a reference level, and a third level voltage V3_comp as a low level.

[0130] Here, the first level voltage V1_comp may be one of the multiple voltage levels in the high level part higher than the average level of the distorted common voltage Vcom. The second level voltage V2_comp may be the average level of the distorted common voltage Vcom. The third level voltage V3_comp may be one of the multiple voltage levels in the low level part lower than the average level of the distorted common voltage Vcom.

[0131] At this time, the compensated common voltage Vcom_comp may include the first level voltage V1_comp and the third level voltage V3_comp, without the second level voltage V2_comp.

[0132] Therefore, by determining the size of the split-type touch electrode TE and the driving method for providing the scan signal SCAN, the distorted waveform of the common voltage Vcom can be calculated or detected. Therefore, by providing a compensated common voltage Vcom_comp corresponding to the distorted waveform of the common voltage Vcom according to the supply time of the common voltage Vcom, the distortion of the common voltage Vcom can be cancelled out.

[0133] The touch display device 100 of the present disclosure can be applied not only to the split type in which a plurality of touch electrodes TE are separated from each other, but also to the woven type in which touch electrodes TE of different sizes are provided in adjacent rows or columns.

[0134] 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.

[0135] Referring to 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, and the touch electrode group TEG includes four long touch electrodes TE1_L-TE4_L and four short touch electrode blocks, and each short touch electrode block includes four short touch electrodes connected by the same line.

[0136] In other words, in the row direction, the length of each long touch electrode TE1_L, TE2_L, TE3_L, TE4_L may correspond to the total length of four short touch electrodes (for example, 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 a short touch line (for example, TL1_S). Therefore, four short touch electrodes arranged in the column direction may constitute one short touch electrode block connected by the same line. In addition, the four long touch electrodes and the four short touch electrode blocks connected by four lines corresponding to the four short touch electrode blocks may constitute one touch electrode group TEG.

[0137] In the case of a 4×4 woven-type touch electrode structure, among two adjacent rows, the number of long touch electrodes in the row where the long touch electrodes are arranged is 1 / 4 of the number of short touch electrodes in the row where the short touch electrodes are arranged. Therefore, the length of each long touch electrode among the long touch electrodes TE1_L, TE2_L, TE3_L, TE4_L is approximately four times the length of the short touch electrode.

[0138] In this case, the woven 4×4 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 in the column direction (e.g., TE(1)1_S, TE(2)1_S, TE(3)1_S, TE(4)1_S) are connected to a short touch line (e.g., TL1_S).

[0139] Therefore, the four short touch electrodes (e.g., TE(1)1_S, TE(2)1_S, TE(3)1_S, TE(4)1_S) connected to the short touch line (e.g., 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 each connected by the same line.

[0140] As a result, each of the four long touch lines TL1_L, TL2_L, TL3_L, TL4L is connected to each of the four long touch electrodes TE1_L, TE2_L, TE3_L, TE4_L, and each of the short touch electrode blocks connected by the same line among the four short touch electrode blocks is connected to each of the short touch lines TL1_S, TL2_S, TL3_S, TL4_S. Therefore, in the case of the woven 4×4 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.

[0141] Therefore, compared with the split-type touch electrode structure, the woven touch electrode structure has the effect of reducing the number of touch lines and touch channels.

[0142] On the other hand, although the size of the touch electrode group TEG can be changed differently, the size of the touch electrode group TEG can be determined according to the distance between the finger positions or stylus positions for detecting multi-touch, so as to effectively arrange the touch electrodes TE on the display panel 110 and increase the detection accuracy of multi-touch.

[0143] On the other hand, a plurality of woven touch electrode groups TEG can be arranged in the display panel 110 in the horizontal and vertical directions. In this case, each touch electrode group TEG is electrically separated in the active area of the display panel 110 where an image is displayed, but in the non-active area of the display panel 110 where no image is displayed, it can be connected to the touch driving circuit 130 through the touch line TL.

[0144] Figure 10 A signal waveform is shown, which shows an example of the distortion of the common voltage generated in the woven long touch electrode and the compensated common voltage, and Figure 11 A signal waveform is shown, which shows an example of the distortion of the common voltage generated in the woven short touch electrode and the compensated common voltage in the touch display device according to an embodiment of the present disclosure.

[0145] Referring to Figure 10 and Figure 11 , the woven touch electrode TE in the touch display device 100 according to an embodiment of the present disclosure can be formed of a long touch electrode and a short touch electrode having different lengths.

[0146] In this case, since the loads transmitted to the long touch electrode and the short touch electrode are different, in the long touch electrode and the short touch electrode, the distortion of the common voltage Vcom caused by the parasitic capacitance Cgc formed between the gate node where the thin film transistor TFT is provided with the scan signal and the touch electrode TE provided with the common voltage Vcom may be different.

[0147] For example, since the length of the long touch electrode in the woven 4×4 touch electrode structure is about 4 times the length of the short touch electrode, the distortion waveform of the common voltage Vcom can be larger and wider compared with the short touch electrode.

[0148] On the other hand, since the length of the short touch electrode in the woven 4×4 touch electrode structure is about 1 / 4 of the length of the long touch electrode, the distortion waveform of the common voltage Vcom can be lower and narrower compared with the long touch electrode. However, since the four short touch electrodes arranged in the column direction form a short touch electrode block connected by the same line, the distortion waveform of the common voltage Vcom can be different compared with the split touch electrode structure.

[0149] Therefore, by independently considering the distortion waveforms of the common voltage Vcom in the long touch electrode and the short touch electrode of the woven structure, a compensated common voltage Vcom_comp capable of canceling the distortion can be generated. As a result, by independently supplying the compensated common voltage Vcom_comp to the long touch electrode and the short touch electrode, display defects due to brightness deviation in the woven touch electrode structure can be reduced.

[0150] In this case, similar to the split-type touch electrode structure, a compensated common voltage Vcom_comp capable of canceling the distortion of the common voltage Vcom can be formed in the form of a pulse signal having multiple levels. For example, the compensated common voltage Vcom_comp can be composed of a pulse waveform having a first-level voltage V1_comp as a high level, a second-level voltage V2_comp as a reference level, and a third-level voltage V3_comp as a low level.

[0151] The first-level voltage V1_comp can be one of multiple voltage levels in the high-level part higher than the average level of the distorted common voltage Vcom. The second-level voltage V2_comp can be the average level of the distorted common voltage Vcom. The third-level voltage V3_comp can be one of multiple voltage levels in the low-level part lower than the average level of the distorted common voltage Vcom.

[0152] At this time, the compensated common voltage Vcom_comp can include the first-level voltage V1_comp and the third-level voltage V3_comp, without the second-level voltage V2_comp.

[0153] Accordingly, by determining the sizes of the woven long touch electrode and the woven short touch electrode and the driving method for providing the scan signal SCAN, the distorted waveform of the common voltage Vcom can be calculated or detected. Therefore, by providing the compensated common voltage Vcom_comp corresponding to the distorted waveform of the common voltage Vcom according to the supply time of the common voltage Vcom, the distortion of the common voltage Vcom can be canceled.

[0154] In addition, the touch display device 100 of the present disclosure can provide a compensated common voltage to cancel the distortion of the common voltage during the transition period between the display driving period and the touch driving period.

[0155] Figure 12 A signal waveform is shown, which shows an example of the compensated common voltage provided during the transition period between the display driving period and the touch driving period in the touch display device according to an embodiment of the present disclosure.

[0156] Refer to Figure 12 , the operation of the gate driving circuit in the touch display device 100 according to an embodiment of the present disclosure can be temporarily stopped during the process of entering the touch driving period TP from the display driving period DP. Then, the operation of the gate driving circuit can be restarted at the start point of the display driving period DP after the touch driving period TP ends.

[0157] Accordingly, during a period when the gate driving circuit operates discontinuously, distortion of the common voltage Vcom may occur in some gate lines. Therefore, such distortion can cause defects, such as horizontal lines due to luminance differences.

[0158] To cancel the distortion of the common voltage Vcom, a compensated common voltage Vcom_comp corresponding to the distortion waveform of the common voltage Vcom can be provided according to the supply time of the common voltage Vcom.

[0159] In this case, the compensated common voltage Vcom_comp provided during the transition period between the display driving period DP and the touch driving period TP can be a pulse signal with multiple levels in the case of overlapping distortion, but can be a single-level signal with a constant level in the case of transition distortion.

[0160] This is because: The transition distortion caused by the transition operation between the display driving period DP and the touch driving period TP may cause a simple distortion of the common voltage Vcom, which is different from the overlapping distortion that occurs during the period when multiple scan signals SCAN overlap.

[0161] However, the pulse width and level of the compensated common voltage Vcom_comp provided during the transition period between the display driving period DP and the touch driving period TP can be changed according to the shape of the touch electrode TE.

[0162] For example, in the case of a split-type touch electrode TE, since multiple gate lines are provided on one touch electrode TE, the transition period between the display driving period DP and the touch driving period TP may occur in the central part of the touch electrode TE, or may occur in the edge part of the touch electrode TE. However, since the split-type touch electrodes have the same size, the waveform of the compensated common voltage Vcom_comp to be provided to the touch electrode TE can be determined according to the average value of the distorted common voltage.

[0163] On the other hand, as described above, since the lengths of the long touch electrodes and the short touch electrodes in the braided touch electrode TE are different, the distortion waveforms of the common voltage Vcom in the long touch electrodes and the short touch electrodes may be different. Therefore, the compensated common voltages Vcom_comp provided to the long touch electrodes and the short touch electrodes during the transition period can have different widths and magnitudes.

[0164] Here, an exemplary case is shown in which a compensated common voltage Vcom_comp is provided during a display driving period DP before entering a touch driving period TP and during a display driving period DP after the touch driving period TP ends. However, the compensated common voltage Vcom_comp may be provided during the touch driving period TP after entering the touch driving period TP, or during a transition period between the display driving period DP and the touch driving period TP.

[0165] In addition, the touch display device 100 of the present disclosure may include a common voltage compensation line for supplying the compensated common voltage Vcom_comp to the touch electrode TE to compensate for distortion of the common voltage Vcom.

[0166] Figure 13 An exemplary structure of a touch electrode including a common voltage compensation line in a touch display device according to an embodiment of the present disclosure is shown.

[0167] Referring to Figure 13 , the display panel 110 in the touch display device 100 according to an embodiment of the present disclosure may include an active area where an image is displayed and a non-active area where no image is displayed.

[0168] The touch electrode TE may be disposed on the active area. The touch driving circuit 130 and various signal lines may be disposed on the non-active area outside the active area.

[0169] The active area may include a plurality of touch lines TL11 - TL16, TL21 - TL26, TL31 - TL36, TL41 - TL46, TL51 - TL56 and a plurality of common voltage compensation lines CL11 - CL16, CL21 - CL26, CL31 - CL36. The plurality of touch lines TL11 - TL16, TL21 - TL26, TL31 - TL36, TL41 - TL46, TL51 - TL56 may be connected to each of the touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36, TE41 - TE46, TE51 - TE56 divided in a first direction (e.g., horizontal direction) and a second direction (e.g., vertical direction) that cross each other, and may be arranged parallel to each other in the second direction. The plurality of common voltage compensation lines CL11 - CL16, CL21 - CL26, CL31 - CL36 may be respectively connected to at least some of the touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36 among the touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36, TE41 - TE46, TE51 - TE56.

[0170] A plurality of common voltage compensation lines CL11 - CL16, CL21 - CL26, CL31 - CL36 may be arranged in parallel with touch lines TL11 - TL16, TL21 - TL26, TL31 - TL36, TL41 - TL46, TL51 - TL56 to which touch drive signals or touch sense signals are transmitted.

[0171] Here, the plurality of common voltage compensation lines CL11 - CL16, CL21 - CL26, CL31 - CL36 correspond to signal lines to which a compensated common voltage Vcom_comp is supplied to cancel common voltage distortion generated due to overlapping scan signals or common voltage distortion generated during a transition period. The plurality of common voltage compensation lines CL11 - CL16, CL21 - CL26, CL31 - CL36 may be connected to all touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36, TE41 - TE46, TE51 - TE56 in the display panel 110, or may be connected to some of the touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36 in the display panel 110.

[0172] When the plurality of common voltage compensation lines CL11 - CL16, CL21 - CL26, CL31 - CL36 are only connected to some of the touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36, TE41 - TE46, TE51 - TE56 provided on the display panel 110, they may be connected to some touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36 having a high load provided at a position far from the touch drive circuit 130.

[0173] Meanwhile, in the display panel 110 including a plurality of touch electrodes TE11 - TE16, TE21 - TE26, TE31 - TE36, TE41 - TE46, TE51 - TE56, in addition to the common voltage compensation lines CL11 - CL16, CL21 - CL26, CL31 - CL36, a plurality of dummy compensation lines and dummy contact holes electrically connecting the dummy compensation lines may be further provided to increase visibility.

[0174] Figure 14 An exemplary block diagram of a circuit for generating a compensated common voltage in a touch display device according to an embodiment of the present disclosure is shown.

[0175] Refer to Figure 14, in the touch display device 100 according to an embodiment of the present disclosure, the compensation common voltage generation circuit for generating the compensated common voltage Vcom_comp may be configured in a power management integrated circuit for power supply, or the compensation common voltage generation circuit may be configured as a separate circuit.

[0176] The compensation common voltage generation circuit may include a first multiplexer MUX1, a second multiplexer MUX2, and a buffer circuit BUF. The first multiplexer MUX1 may receive a first-level voltage V1_comp and a second-level voltage V2_comp as inputs, and may select the first-level voltage V1_comp or the second-level voltage V2_comp as a first output signal according to a first control signal CTR1. The second multiplexer MUX2 may receive the first output signal of the first multiplexer MUX1 and a third-level voltage V3_comp as inputs, and may select a second output signal according to a second control signal CTR2. The buffer circuit BUF transmits the second output signal of the second multiplexer MUX2.

[0177] The first-level voltage V1_comp may be the maximum level of the common voltage Vcom distorted during the overlapping period or the transition period of the scan signal. The second-level voltage V2_comp may be the average level of the distorted common voltage Vcom. The third-level voltage V3_comp may be the minimum level of the distorted common voltage Vcom.

[0178] At this time, by controlling the waveform of the first control signal CTR1 provided to the first multiplexer MUX1 and the waveform of the second control signal CTR2 provided to the second multiplexer MUX2, the waveform of the compensated common voltage Vcom_comp generated from the buffer circuit BUF can be changed in various ways.

[0179] In this case, the buffer circuit BUF may be omitted from the compensation common voltage generation circuit.

[0180] Figure 15 Another exemplary block diagram of a circuit for generating a compensated common voltage in a touch display device according to an embodiment of the present disclosure is shown.

[0181] Refer to Figure 15, in the touch display device 100 according to an embodiment of the present disclosure, the compensation common voltage generation circuit for generating the compensated common voltage Vcom_comp may include a multiplexer MUX and a buffer circuit BUF. The multiplexer MUX may receive the first-level voltage V1_comp, the second-level voltage V2_comp, and the third-level voltage V3_comp as inputs, and may select an output signal through the first control signal CTR1 and the second control signal CTR2. The buffer circuit BUF transmits the output signal of the multiplexer MUX.

[0182] The first-level voltage V1_comp may be one of a plurality of voltage levels in the high-level part that is higher than the average level of the distorted common voltage Vcom during the overlapping period or the transition period of the scan signal. The second-level voltage V2_comp may be the average level of the distorted common voltage Vcom. The third-level voltage V3_comp may be one of a plurality of voltage levels in the low-level part that is lower than the average level of the distorted common voltage Vcom.

[0183] Therefore, by controlling the waveforms of the first control signal CTR1 and the second control signal CTR2 provided to the multiplexer MUX, the waveform of the compensated common voltage Vcom_comp generated from the buffer circuit BUF can be changed in various ways.

[0184] In this case, the buffer circuit BUF may be omitted from the compensation common voltage generation circuit.

[0185] As described above, by generating a compensated common voltage with a different waveform according to the structure of the touch electrode and providing the compensated common voltage to the corresponding touch electrode through the common voltage compensation line to cancel the distortion of the common voltage during the overlapping period of the scan signal or the transition period between the display driving period and the touch driving period, the touch display device 100 of the present disclosure can cancel the distortion of the common voltage and improve the image quality.

[0186] The foregoing description has been presented to enable any person skilled in the art to make and use the inventive concept, and has been provided in the context of a particular application and its requirements. Various modifications, additions, and substitutions to the described embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the spirit and scope of the invention. The foregoing description and drawings have provided only examples of the inventive concept for purposes of illustration. That is, the disclosed embodiments are intended to illustrate the scope of the inventive concept of the invention. Therefore, the scope of the invention is not limited to the embodiments shown, but should be accorded the broadest scope consistent with the claims. The scope of protection of the invention should be construed based on the appended claims, and all inventive concepts within the scope of their equivalents should be construed as being included within the scope of the invention.

Claims

1. A touch display device, comprising: a display panel including a plurality of touch electrodes; a display driving circuit configured to provide a scan signal to the display panel through a plurality of gate lines; and a touch driving circuit configured to perform a touch sensing operation based on capacitance changes of the plurality of touch electrodes, and provide at least one compensated common voltage having a waveform for canceling at least one distorted common voltage based on the structure and shape of the plurality of touch electrodes to the plurality of touch electrodes according to the time of at least one distorted common voltage transmitted through a plurality of touch lines, so as to reduce distortion of the common voltage during an overlapping period in which adjacent scan signals overlap during a display driving period.

2. The touch display device according to claim 1, wherein the plurality of touch electrodes are split-type touch electrodes having the same horizontal length and the same vertical length.

3. The touch display device according to claim 1, wherein the plurality of touch electrodes are woven-type touch electrodes, wherein a plurality of first touch electrodes having a first length in a first direction and a plurality of second touch electrodes having a second length smaller than the first length are alternately arranged in a second direction, and the plurality of second touch electrodes arranged in the second direction are connected to the same touch line.

4. The touch display device according to claim 3, wherein each of the plurality of first touch electrodes is connected to a corresponding one of the touch lines.

5. The touch display device according to claim 3, wherein the at least one compensated common voltage has different waveforms provided to the plurality of first touch electrodes and the plurality of second touch electrodes.

6. The touch display device according to claim 1, wherein the at least one compensated common voltage includes a pulse signal having: a first level among a plurality of voltage levels in a high-level portion greater than an average level of the distorted common voltage, a second level corresponding to the average level of the distorted common voltage, and a third level among a plurality of voltage levels in a low-level portion less than the average level of the distorted common voltage, to cancel distortion of the common voltage during the overlapping period.

7. The touch display device according to claim 1, wherein the at least one compensated common voltage includes a single-level signal having a constant level to cancel distortion of the common voltage during a transition period between the display driving period and the touch driving period.

8. The touch display device according to claim 7, wherein the at least one compensated common voltage is provided during the display driving period before entering the touch driving period and during the display driving period after the touch driving period ends.

9. The touch display device according to claim 1, further comprising: a compensated common voltage generation circuit, including: A first multiplexer configured to receive a first-level voltage and a second-level voltage as input signals and select a first output signal according to a first control signal; A second multiplexer configured to receive a third-level voltage and the first output signal of the first multiplexer as input signals and select a second output signal according to a second control signal; and A buffer circuit configured to receive the second output signal of the second multiplexer and transmit the at least one compensated common voltage.

10. The touch display device according to claim 1, further comprising: A compensated common voltage generation circuit, comprising: A multiplexer configured to receive a first-level voltage, a second-level voltage, and a third-level voltage as input signals and select an output signal through a first control signal and a second control signal; and A buffer circuit configured to receive the output signal of the multiplexer and transmit the at least one compensated common voltage.

11. The touch display device according to claim 1, further comprising: A plurality of common voltage compensation lines arranged in parallel with a plurality of touch lines for transmitting touch signals to the plurality of touch electrodes, and the plurality of common voltage compensation lines are configured to provide the at least one compensated common voltage to the plurality of touch electrodes.

12. A touch driving circuit, comprising: A plurality of touch lines configured to transmit touch driving signals to a display panel including a plurality of touch electrodes; A touch sensing circuit configured to provide the touch driving signals to the plurality of touch electrodes through the plurality of touch lines and receive touch sensing signals from the plurality of touch electrodes; A touch controller configured to detect the presence of a touch and calculate touch coordinates according to the touch sensing signals; and A compensated common voltage generation circuit configured to generate at least one compensated common voltage having a waveform for canceling at least one distortion of the common voltage based on the structure and shape of the plurality of touch electrodes, and the at least one compensated common voltage will be provided to the plurality of touch electrodes according to the time of the at least one distorted common voltage transmitted through the plurality of touch lines so as to cancel the at least one distorted common voltage during an overlapping period when adjacent scan signals overlap during a display driving period.

13. The touch driving circuit according to claim 12, wherein the plurality of touch electrodes are woven touch electrodes, wherein a plurality of first touch electrodes having a first length in a first direction and a plurality of second touch electrodes having a second length less than the first length are alternately arranged in a second direction, and the plurality of second touch electrodes arranged in the second direction are connected to the same touch line; and Wherein, the at least one compensated common voltage has different waveforms provided to the plurality of first touch electrodes and the plurality of second touch electrodes.

14. The touch driving circuit according to claim 12, wherein, during the overlapping period, the at least one compensated common voltage includes a pulse signal having: a first level among a plurality of voltage levels in a high-level portion greater than an average level of the distorted common voltage, a second level corresponding to the average level of the distorted common voltage, and a third level among a plurality of voltage levels in a low-level portion less than the average level of the distorted common voltage.

15. The touch driving circuit according to claim 12, wherein, the at least one compensated common voltage includes a single-level signal having a constant level to cancel the at least one distorted common voltage during a transition period between the display driving period and the touch driving period.

16. The touch driving circuit according to claim 15, wherein, during the display driving period before entering the touch driving period and during the display driving period after the touch driving period ends, the at least one compensated common voltage is provided.

17. The touch driving circuit according to claim 12, wherein, the compensated common voltage generation circuit includes: a first multiplexer configured to receive a first-level voltage and a second-level voltage as input signals and select a first output signal according to a first control signal; a second multiplexer configured to receive a third-level voltage and the first output signal of the first multiplexer as input signals and select a second output signal according to a second control signal; and a buffer circuit configured to receive the second output signal of the second multiplexer and transmit the at least one compensated common voltage.

18. The touch driving circuit according to claim 12, wherein, the compensated common voltage generation circuit includes: a multiplexer configured to receive a first-level voltage, a second-level voltage, and a third-level voltage as input signals and select an output signal through a first control signal and a second control signal; and a buffer circuit configured to receive the output signal of the multiplexer and transmit the at least one compensated common voltage.

19. The touch driving circuit according to claim 12, further includes: a plurality of common voltage compensation lines arranged in parallel with the plurality of touch lines and configured to provide the at least one compensated common voltage to the plurality of touch electrodes.

20. A touch driving method for a touch display device, the touch display device includes: a display driving circuit configured to provide a scan signal to a display panel having a plurality of touch electrodes; and a touch driving circuit configured to provide a touch driving signal to the display panel and sense a touch based on a touch sensing signal received in response to the touch driving signal, the touch driving method comprising: detecting an overlapping distortion of a common voltage during an overlapping period in which adjacent scan signals overlap during a display driving period; generating at least one compensated common voltage according to the structure and shape of the plurality of touch electrodes to cancel at least one distorted common voltage; and during the overlapping period, providing the at least one compensated common voltage to the plurality of touch electrodes according to the time of the at least one distorted common voltage transmitted through a plurality of touch lines.

21. The touch driving method according to claim 20, wherein, the plurality of touch electrodes are woven touch electrodes, wherein a plurality of first touch electrodes having a first length in a first direction and a plurality of second touch electrodes having a second length smaller than the first length are alternately arranged in a second direction, and the plurality of second touch electrodes arranged in the second direction are connected to the same touch line; and wherein the at least one compensated common voltage has different waveforms provided to the plurality of first touch electrodes and the plurality of second touch electrodes.

22. The touch driving method according to claim 20, wherein, during the overlapping period, the at least one compensated common voltage includes a pulse signal having: a first level among a plurality of voltage levels in a high level portion greater than an average level of the distorted common voltage, a second level corresponding to the average level of the distorted common voltage, and a third level among a plurality of voltage levels in a low level portion smaller than the average level of the distorted common voltage.

23. The touch driving method according to claim 20, wherein, the at least one compensated common voltage includes a single-level signal having a constant level to cancel the at least one distorted common voltage during a transition period between the display driving period and the touch driving period.

24. The touch driving method according to claim 23, wherein, during the display driving period before entering the touch driving period and during the display driving period after the touch driving period ends, the at least one compensated common voltage is provided.

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