Touch display device

Abstract

Disclosed is a touch display device that detects multiple touches in a touch sensing mechanism for sensing surface capacitance changes of touch electrodes. The touch display device includes: a display panel including a touch electrode having a plurality of measurement positions; a switching circuit connected to each measurement position of the touch electrode; and a touch driving circuit connected to each measurement position of the touch electrode via the switching circuit, where the touch driving circuit is configured to apply a touch driving signal to the touch electrode, receive a sensing value from the measurement position based on an operation of the switching circuit, and calculating coordinates of a plurality of touch points on the touch electrode based on the sensing value.

Description

Technical Field

[0001] The present invention relates to a touch display device. Background Art

[0002] Display devices used in computer monitors, TVs, mobile phones, and the like include organic light-emitting display devices (OLEDs) that emit light by themselves, liquid crystal display devices (LCDs) that require a separate light source, and the like.

[0003] The application range of display devices is becoming more and more diverse, including not only computer monitors and TVs but also personal portable devices. Research is being conducted on display devices having a large display area size and reduced volume and weight.

[0004] Furthermore, development of touch technology is ongoing to apply a touch-based input mechanism that allows a user to easily, intuitively, and conveniently input information or commands to a display device. Summary of the Invention

[0005] In order to apply a touch-based input mechanism to a display device, a mechanism is adopted in which a touch panel including a touch sensor is combined with a display panel or a touch sensor is built into the display panel. In this mechanism, the touch sensor detects a touch based on the sensing result of the capacitance change of the touch electrode surface.

[0006] However, the mechanism used to sense changes in the surface capacitance of a single monolithic touch electrode can only detect a single touch and may not be able to detect multiple touches.

[0007] Therefore, an object of the present invention is to provide a touch display device that can detect multi-touch in a touch sensing mechanism for sensing capacitance changes of touch electrode surfaces to improve touch performance.

[0008] The objectives of the present invention are not limited to the above-mentioned objectives. Other objectives and advantages of the present invention that are not mentioned hereunder can be understood based on the following description and can be more clearly understood based on the embodiments of the present invention. In addition, it will be readily understood that the objectives and advantages of the present invention can be achieved by the methods shown in the claims and their combinations.

[0009] One aspect of the present invention provides a touch display device, comprising: a display panel, the display panel including touch electrodes having multiple measurement positions; a switching circuit connected to each measurement position of the touch electrodes; and a touch drive circuit connected to each measurement position of the touch electrodes via the switching circuit, wherein the touch drive circuit is configured to apply a touch drive signal to the touch electrodes, receive a sensing value from the measurement position based on the operation of the switching circuit, and calculate the coordinates of multiple touch points on the touch electrodes based on the sensing values.

[0010] Another aspect of the present invention provides a touch display device, comprising: a display panel including touch electrodes and configured to operate in a time-division manner in a display period for displaying an image and a touch period for detecting a touch; first, second, third, and fourth switching circuits connected to first, second, third, and fourth measurement positions corresponding to four corners of the touch electrodes, respectively; and a touch drive circuit connected to each of the first, second, third, and fourth measurement positions of the touch electrodes via each of the first, second, third, and fourth switching circuits, wherein during the touch period, the touch drive circuit is configured to apply a touch drive signal to the touch electrodes, receive sensed values from the first, second, third, and fourth measurement positions based on the operation of the first, second, third, and fourth switching circuits, and calculate coordinates of multiple touch points on the touch electrodes based on the sensed values.

[0011] Yet another aspect of the present invention provides a touch display device, comprising: a display panel, the display panel including a touch electrode having multiple measurement positions; a switching circuit connected to each measurement position of the touch electrode; and a touch drive circuit connected to each measurement position of the touch electrode via the switching circuit, wherein the touch drive circuit is configured to apply a touch drive signal to the touch electrode, receive a sensing value from the measurement position based on the operation of the switching circuit, and calculate the coordinates of multiple touch points on the touch electrode based on the sensing value, wherein the touch electrode includes four corners and four middle points of the corresponding four sides, and wherein the measurement positions include first to eighth measurement positions corresponding to the four corners and the four middle points.

[0012] According to aspects of a touch display device, touch performance may be improved by detecting multi-touch in a touch sensing mechanism for sensing a change in capacitance of a touch electrode.

[0013] Furthermore, the touch sensor can detect multiple touches on a single electrode, thereby reducing the manufacturing cost of the touch panel.

[0014] Furthermore, when the touch panel is combined with the display panel, the brightness and clarity of the displayed image can be maintained.

[0015] In addition, the production energy of the touch panel can be reduced and the touch panel process can be optimized.

[0016] The effects of the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

[0017] In addition to the above-described effects, specific effects of the present invention will be described together with specific details for implementing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a block diagram of a touch display device according to an embodiment of the present invention.

[0019] Figure 2 is a diagram illustrating a specific configuration of a touch display device according to an embodiment of the present invention.

[0020] Figure 3 is a diagram illustrating multi-touch sensing in a touch display device according to an embodiment of the present invention.

[0021] Figure 4 It is illustrated in Figure 3 Block diagram of the touch drive circuit in .

[0022] Figure 5 is a graph showing measurement positions and the number of measurement values in the on and off states of a switch circuit in a touch display device according to an embodiment of the present invention.

[0023] Figure 6 An equivalent circuit based on the sheet resistance at the coordinates of each of all positions on the touch electrodes in the touch display device according to the embodiment of the present invention is shown.

[0024] Figure 7 Shows when the object only touches Figure 6 The measurement result of the first touch point P1 in .

[0025] Figure 8 Shows when the object only touches Figure 6 The measurement result of the second touch point P2 in .

[0026] Figure 9 Shows when objects touch simultaneously Figure 6The measurement results of the first touch point P1 and the second touch point P2.

[0027] Figure 10 is a diagram illustrating multi-touch sensing in a touch display device according to another embodiment of the present invention. DETAILED DESCRIPTION

[0028] The advantages and features of the present invention and the methods for achieving these advantages and features are described in detail below and in the accompanying drawings. Figure 1 The following detailed description of the embodiments will become clear. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in a variety of different forms. Therefore, these embodiments are set forth only to complete the disclosure of the present invention and fully convey the scope of the present invention to those skilled in the art. The present invention is limited only by the scope of the claims.

[0029] For the sake of simplicity and clarity of illustration, the elements in the accompanying drawings are not necessarily drawn to scale. The same reference numerals in different figures represent the same or similar elements and thus perform similar functions. In addition, for the sake of simplicity of description, descriptions and details of well-known steps and elements are omitted. In addition, in the following detailed description of the present invention, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be understood that the present invention can be practiced without these specific details. In other cases, well-known methods, processes, components and circuits are not described in detail to avoid unnecessarily obscuring aspects of the present invention. Examples of various embodiments are further illustrated and described below. It will be understood that the description herein is not intended to limit the claims to the specific embodiments described. On the contrary, it is intended to cover alternatives, modifications and equivalents that may be included in the spirit and scope of the present invention as defined in the appended claims.

[0030] The shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for illustrating the embodiments of the present invention are merely exemplary, and the present invention is not limited thereto.

[0031] The terms used herein are intended to describe only the purpose of specific embodiments and are not intended to limit the present invention. As used herein, singular compositions are intended to also include plural compositions, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "having," "containing" used in this specification indicate the presence of the features, integers, operations, elements and / or components mentioned, but do not exclude the presence or addition of one or more other features, integers, operations, elements, components and / or parts thereof. As used herein, the term "and / or" includes any and all combinations of one or more relevant listed items. Expressions such as "at least one of" before a list of elements can modify the entire list of elements, rather than modifying the individual elements of the list. When interpreting numerical values, even if not explicitly described, errors or tolerances may also exist therein.

[0032] Furthermore, it will be understood that when a first element or layer is referred to as being present on a second element or layer, the first element can be directly disposed on the second element or layer, or can be indirectly disposed on the second element or layer with a third element or layer disposed therebetween. It will be understood that when an element or layer is referred to as being connected to or joined to another element or layer, it can be directly on or directly connected to or directly joined to the other element or layer, or one or more intervening elements or layers can be present. It will be understood that when an element or layer is referred to as being between two elements or layers, it can be the only element or layer between the two elements or layers, or one or more intervening elements or layers can also be present.

[0033] Furthermore, as used herein, when a layer, film, region, plate, etc. is disposed on or on top of another layer, film, region, plate, etc., the former may be in direct contact with the latter, or another layer, film, region, plate, etc. may be disposed between the former and the latter. As used herein, when a layer, film, region, plate, etc. is disposed directly on or on top of another layer, film, region, plate, etc., the former is in direct contact with the latter, without another layer, film, region, plate, etc. disposed between the former and the latter. Furthermore, as used herein, when a layer, film, region, plate, etc. is disposed under or below another layer, film, region, plate, etc., the former may be in direct contact with the latter, or another layer, film, region, plate, etc. may be disposed between the former and the latter. As used herein, when a layer, film, region, plate, etc. is disposed directly under or below another layer, film, region, plate, etc., the former is in direct contact with the latter, without another layer, film, region, plate, etc. disposed between the former and the latter.

[0034] When using terms such as “after”, “subsequently”, “before”, etc. to describe a temporal relationship, for example, the temporal sequence between two events, other events may occur in between unless it is indicated as “directly after”, “directly after” or “directly before”.

[0035] When a certain embodiment can be implemented differently, the functions or operations specified in a specific block may occur in an order different from the order indicated in the flow chart. For example, two consecutive blocks may actually be executed substantially simultaneously, or the two blocks may be executed in reverse order depending on the functions or operations involved.

[0036] It will be understood that although the text may use the terms "first," "second," "third," etc. to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section described below could be referred to as a second element, component, region, layer, or section without departing from the spirit and scope of the present invention.

[0037] When an embodiment can be implemented differently, the functions or operations specified in a specific block can be performed in an order different from the order specified in the flow chart. For example, two consecutive blocks can actually be performed substantially simultaneously, or the blocks can be performed in reverse order according to the related functions or operations.

[0038] The features of each embodiment of the present invention may be combined with each other in part or in whole, may be technically related to each other or operate with each other, and the embodiments may be implemented independently of each other or may be implemented together in an associated relationship.

[0039] When interpreting numerical values, even if there is no explicit description thereof separately, the values are interpreted as including the error range.

[0040] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this inventive concept belongs. It will be further understood that terms, such as those defined in common dictionaries, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or exaggerated sense unless expressly defined herein.

[0041] As used herein, "embodiment," "example," "aspect," etc. should not be construed to imply that any aspect or design described is superior or advantageous over other aspects or designs.

[0042] Furthermore, the term "or" means an inclusive or rather than an exclusive or. That is, unless specified otherwise or clear from the context, the expression "x employs a or b" means any of the natural inclusive permutations.

[0043] The terms used in the following description are selected to be common and general terms in the relevant technical fields. However, other terms may exist depending on the development and / or changes of technology, protocols, preferences of technicians, etc. Therefore, the terms used in the following description should not be understood as limiting the technical concepts, but should be understood as examples of terms used to illustrate the embodiments.

[0044] In addition, in specific cases, the applicant may arbitrarily select terms, in which case their detailed meanings will be described in the corresponding description section. Therefore, the terms used in the following description should not be simply understood based on the names of the terms, but also based on the meaning and content of the terms throughout the detailed description.

[0045] When describing a signal flow, for example, when a signal is transmitted from node A to node B, it may include a case where the signal is transmitted from node A to node B via another node unless the phrase "immediately transmitted" or "directly transmitted" is used.

[0046] Throughout the present invention, “A and / or B” means A, B, or A and B, unless otherwise specified; “C to D” means C to D inclusive, unless otherwise specified.

[0047] "At least one of" should be understood to include any combination of one or more of the listed components. For example, at least one of the first, second, and third components refers not only to the first, second, or third component, but also to all combinations of two or more of the first, second, and third components.

[0048] Hereinafter, embodiments of the present invention will be described using the accompanying drawings. For the sake of illustration, the proportion of each component shown in the accompanying drawings is different from its actual proportion, and therefore, the present invention is not limited to the proportions shown in the accompanying drawings.

[0049] Hereinafter, a touch display device according to some embodiments will be described.

[0050] As used herein, multi-touch may be defined as touching at least two points on touch electrodes used in a touch sensor of a display panel.

[0051] Figure 1 is a block diagram of a touch display device according to an embodiment of the present invention.

[0052] The touch display device may include a display panel 100 , a data driving circuit 230 , a gate driving circuit 240 , a power supply circuit 250 , and a touch driving circuit 300 .

[0053] The display panel 100 may include a touch panel in which touch electrodes and / or touch wiring for touch sensing are provided. In this regard, the touch panel may refer to a portion of the display panel 100 including components required for touch sensing, or may refer to a collection of touch electrodes and / or touch wiring provided in the display panel 100.

[0054] The display panel 100 can operate in a time-division manner in a display period for image display and a touch period for touch sensing. During the display period, data of an input image can be written to the pixel array. During the touch period, a touch drive signal can be applied to the touch electrodes, thereby detecting a touch input to the display panel.

[0055] The data driving circuit 230 may drive the data lines S1 to Sm provided in the display panel 100. For example, during a display period, the data driving circuit 230 may apply data voltages to the data lines S1 to Sm to drive the plurality of sub-pixels sp.

[0056] The gate driving circuit 240 may drive the gate lines G1 to Gn provided in the display panel 100. For example, during a display period, the gate driving circuit 240 may apply scan signals to the gate lines G1 to Gn to drive the plurality of sub-pixels sp.

[0057] The power circuit 250 may apply a high potential power voltage and a low potential power voltage to the high potential power terminal and the low potential power terminal of each sub-pixel sp via the power line, respectively, during a display period.

[0058] Furthermore, during the touch period, the power supply circuit 250 may apply a modulated high-potential power supply voltage and a modulated low-potential power supply voltage having the same period and amplitude as the touch drive signal applied to the touch electrode to the high-potential power supply terminal and the low-potential power supply terminal of each sub-pixel sp, respectively. This can minimize parasitic capacitance between the touch electrode and the power line.

[0059] The touch driving circuit 300 may sense capacitance changes due to single touch and multi-touch on the display panel 100 using touch electrodes and / or touch wiring provided in the display panel 100. The touch driving circuit 300 may then calculate the presence or absence of a touch and coordinates corresponding to the touch based on the sensing result.

[0060] The timing controller 220 can receive timing signals such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a data enable signal DE, and a main clock MCLK from the host system 210, and synchronize the operation timings of the data driving circuit 230 and the gate driving circuit 240 with each other based on the received timing signals.

[0061] The host system 210 may convert the image data RGB into a format suitable for the resolution of the display panel 100. The host system 210 may transmit the timing signals Vsync, Hsync, DE, and MCLK together with the image data RGB to the timing controller 220. In addition, the host system 210 may execute an application program related to the coordinate data TDATA of the touch input received from the touch driving circuit 300.

[0062] The timing controller 220 or the host system 210 may generate a synchronization signal Tsync to synchronize the operation timing of each of the data driving circuit 230 , the gate driving circuit 240 , the power supply circuit 250 , and the timing controller 200 with the operation timing of the touch driving circuit 300 .

[0063] The synchronization signal Tsync can be created as follows: a first period having a first signal level and a second period having a second signal level can repeat. In this regard, the first signal level can be higher than the second signal level. In the synchronization signal Tsync, the first period can correspond to the display period (Td), and the second period can correspond to the touch period (Tt).

[0064] In addition, the synchronization signal Tsync may correspond to the vertical synchronization signal Vsync used for display operation. In this case, the display period (Td) may correspond to the active period in the vertical synchronization signal Vsync, and the touch period (Tt) may correspond to the blank period in the vertical synchronization signal Vsync.

[0065] Figure 2 is a diagram illustrating a specific configuration of a touch display device according to an embodiment of the present invention.

[0066] Reference Figure 2 , the touch display device may include: a display panel layer DPL, in which a plurality of sub-pixels are formed in a display area AA; and a touch panel layer TPL disposed on the display panel layer DPL.

[0067] The data driving circuit 230 and the gate driving circuit 240 may be disposed in a non-display area of the display panel layer DPL.

[0068] The touch panel layer TPL may include a shielding electrode layer 110 formed on top of the display panel layer DPL; an overlay layer 120 formed on top of the shielding electrode layer 110; an optically transparent adhesive layer 130 formed on top of the overlay layer 120; and touch electrodes 140 formed on top of the optically transparent adhesive layer 130. The shielding electrode layer 110 may be made of a conductive material. Each of the overlay layer 120 and the optically transparent adhesive layer 130 may be made of a transparent material.

[0069] The touch electrode 140 may be formed as a single-piece electrode covering the touch area of the display panel. A finger capacitor Cf may be generated between an object and the touch electrode 140. A finger capacitor may be defined as a capacitor generated between the object and the touch electrode 140 when the object, such as a finger or a stylus, touches the touch electrode 140.

[0070] During the touch period, a modulated signal having the same period and amplitude as the touch drive signal may be applied to the shielding electrode layer 110. The shielding electrode layer 110 may be provided between the touch electrode 140 and the display electrode to minimize generation of parasitic capacitors therebetween.

[0071] In this regard, a display electrode can be defined as an electrode required for display operation of a display device. For example, a display electrode can be a high-potential power supply terminal of a drive transistor of a sub-pixel, a cathode of an organic light-emitting element, a data line to which a data voltage is applied, a scan line to which a scan signal is applied, and at least one of a high-potential power supply terminal and a low-potential power supply terminal for generating the applied scan signal.

[0072] The touch display device may further include a shielding electrode driver 260. The shielding electrode driver 260 may apply a modulated signal having the same period and amplitude as the touch driving signal to the shielding electrode layer.

[0073] The first switch sw1 , the second switch sw2 , the third switch sw3 , and the fourth switch sw4 may be respectively connected to a first measurement position, a second measurement position, a third measurement position, and a fourth measurement position which are four corners of the touch electrode, respectively.

[0074] The first switch sw1 , the second switch sw2 , the third switch sw3 , and the fourth switch sw4 may be connected to the touch driving circuit 300 , and may transmit a signal corresponding to a change in capacitance of the touch electrode 140 to the touch driving circuit 300 .

[0075] The touch drive circuit 300 can sense a signal corresponding to a change in capacitance of the touch electrode 140 via the first switch sw1, the second switch sw2, the third switch sw3, and the fourth switch sw4. The touch drive circuit 300 can calculate touch coordinates based on the sensed values. The touch drive circuit 300 may include a touch signal supply circuit 310 that provides a touch drive signal to the touch electrode 140 and a sensing circuit 320 that senses a signal corresponding to a change in capacitance of the touch electrode 140.

[0076] The sensing circuit 320 may include a first sensing circuit, a second sensing circuit, a third sensing circuit, and a fourth sensing circuit. The first sensing circuit may detect a change in capacitance of the touch electrode 140 at a first corner of the touch electrode via a first switch sw1. The second sensing circuit may detect a change in capacitance of the touch electrode at a second corner of the touch electrode via a second switch sw2. The third sensing circuit may detect a change in capacitance of the touch electrode at a third corner of the touch electrode via a third switch sw3. The fourth sensing circuit may detect a change in capacitance of the touch electrode at a fourth corner of the touch electrode via a fourth switch sw4. In this regard, the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position may correspond to the first corner, the second corner, the third corner, and the fourth corner of the touch electrode, respectively.

[0077] exist Figure 2 , the first current signal i1 represents the signal detected by the first sensing circuit, the second current signal i2 represents the signal detected by the second sensing circuit, the third current signal i3 represents the signal detected by the third sensing circuit, and the fourth current signal i4 represents the signal detected by the fourth sensing circuit.

[0078] In addition, the common terminal COM represents a terminal to which a DC voltage is applied. When any one of the first to fourth switches is turned off, a DC voltage may be applied to the touch electrode. For example, when the first to fourth switches are turned off, a DC voltage may be applied via the first to fourth corners of the touch electrode. When the first and second switches are turned off, a DC voltage may be applied via the first and second corners of the touch electrode. In other words, depending on whether the switch is on, a touch drive signal or a DC voltage may be applied to the touch electrode via each corner.

[0079] Figure 3 is a diagram illustrating multi-touch sensing in a touch display device according to an embodiment of the present invention. Figure 4 It is illustrated in Figure 3 Block diagram of the touch drive circuit in .

[0080] Reference Figure 3 and Figure 4The touch display device includes: a touch electrode 140 included in a display panel; switch circuits sw1, sw2, sw3, and sw4 connected to first to fourth measurement positions of the touch electrode 140, respectively; and first to fourth touch drive circuits 300a, 300b, 300c, and 300d, which respectively sense changes in capacitance at four measurement positions based on a single or multiple touch points P1 and P2 via the four switch circuits sw1, sw2, sw3, and sw4. As used herein, depending on the context, the touch drive circuit 300 may refer to each of the first to fourth touch drive circuits 300a, 300b, 300c, and 300d, or may refer to the first to fourth touch drive circuits 300a, 300b, 300c, and 300d as a whole.

[0081] The touch electrode 140 may be formed as a single-piece electrode covering a touch area of the display panel 100. The touch area may correspond to the display area AA of the display panel 100.

[0082] The first to fourth switching circuits sw1, sw2, sw3, and sw4 may be connected to the first to fourth measurement positions of the touch electrode 140, respectively. In this regard, the four measurement positions may correspond to the four corners of the touch electrode 140. Alternatively, in another example, the measurement positions may be set to the corners of the touch electrode and the midpoints between adjacent corners.

[0083] The switching circuits sw1, sw2, sw3 and sw4 may include first, second, third and fourth switches sw1, sw2, sw3 and sw4 respectively connected to first, second, third and fourth measurement positions a, b, c and d as four corners of the touch electrodes.

[0084] Each of the touch drive circuits 300a, 300b, 300c, and 300d can apply a drive signal to the touch electrode 140 and receive a sensed value at each measurement position in response to the conduction of each switch circuit. The touch drive circuit 300 can be configured to calculate the coordinates of multiple touch points on the touch electrode (e.g., the coordinates of the first touch point P1 and the second touch point P2) based on the sensed values at the measurement positions.

[0085] Each of the touch drive circuits 300a, 300b, 300c, and 300d can receive a sensed value at each of the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d in response to each of the first switch sw1, the second switch sw2, the third switch sw3, and the fourth switch sw4 being turned on. Furthermore, the touch drive circuit 300 can be configured to calculate the coordinates of multiple touch points on the touch electrode (e.g., the coordinates of the first touch point P1 and the second touch point P2) based on the sensed values at each of the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d.

[0086] In this regard, the touch drive circuit 300 may be configured to calculate the coordinates of multiple touch points on the touch electrode (e.g., the coordinates of the first touch point P1 and the second touch point P2) based on the corresponding sensed values at the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d, the sensed values at one or more of the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d, the corresponding resistance values R11, R12, R13, and R14 of the corresponding paths from the first touch point P1 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d, and the corresponding resistance values R21, R22, R23, and R24 of the corresponding paths from the second touch point P2 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d. During a touch period, one of the touch drive circuits 300a, 300b, 300c, and 300d may be configured to turn on a corresponding one of the first switch sw1, the second switch sw2, the third switch sw3, and the fourth switch sw4, and obtain a sensed value sensed at a measurement position connected to the turned-on switch. During the touch period, each of the remaining touch drive circuits 300a, 300b, 300c, and 300d may be configured to turn off (or disconnect) each of the remaining switches among the first switch sw1, the second switch sw2, the third switch sw3, and the fourth switch sw4.

[0087] In the touch electrode 140, each of the corresponding resistance values r11, r12, r13, and r14 of the corresponding paths from the first touch point P1 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d, and the corresponding resistance values r21, r22, r23, and r24 of the corresponding paths from the second touch point P2 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d may be preset based on the sheet resistance of the touch electrode 140. That is, all of the corresponding resistance values of the corresponding paths from each coordinate of all positions on the touch electrode 140 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d may be preset based on the sheet resistance or sheet resistance value of the touch electrode 140.

[0088] To recognize the coordinates of the multi-touch points P1 and P2, the touch driving circuits 300a, 300b, 300c, and 300d may operate as follows.

[0089] First, each of all the touch driving circuits 300a, 300b, 300c, and 300d may turn on each of all the first switches sw1, second switches sw2, third switches sw3, and fourth switches sw4 during a touch period, and may obtain each of all the sensing values sensed at all the first measurement positions a, second measurement positions b, third measurement positions c, and fourth measurement positions d, respectively.

[0090] Next, while the third touch driving circuit 300c and the fourth touch driving circuit 300d can respectively turn off the third switch sw3 and the fourth switch sw4, the first touch driving circuit 300a and the second touch driving circuit 300b can respectively turn on the first switch sw1 and the second switch sw2. Thus, the first touch driving circuit 300a and the second touch driving circuit 300b can respectively obtain sensing values at the first measurement position a and the second measurement position b.

[0091] Next, the third touch driving circuit 300c and the fourth touch driving circuit 300d can respectively turn on the third switch sw3 and the fourth switch sw4, while the first touch driving circuit 300a and the second touch driving circuit 300b can respectively turn off the first switch sw1 and the second switch sw2. Thus, the third touch driving circuit 300c and the fourth touch driving circuit 300d can respectively obtain sensing values at the third measurement position c and the fourth measurement position d.

[0092] Thus, the touch drive circuit 300 can be configured to calculate the coordinates of the multiple touch points on the touch electrode (for example, the coordinates of the first touch point P1 and the second touch point P2) based on all of the corresponding sensed values at the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d, the sensed values sensed at the first measurement position a and the second measurement position b when the first switch sw1 and the second switch sw2 are turned on and the third switch sw3 and the fourth switch sw4 are turned off, the sensed values sensed at the third measurement position c and the fourth measurement position d when the first switch sw1 and the second switch sw2 are turned off and the third switch sw3 and the fourth switch sw4 are turned on, the corresponding resistance values R11, R12, R13, and R14 of the corresponding paths from the first touch point P1 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d, and the corresponding resistance values R21, R22, R23, and R24 of the corresponding paths from the second touch point P2 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d.

[0093] Reference Figure 4 The touch driving circuit 300 may include a touch signal supply circuit 310, a sensing circuit 320, and a touch calculator 330. That is, each of the first to fourth touch driving circuits 300a, 300b, 300c, and 300d may include a touch signal supply circuit 310, a sensing circuit 320, and a touch calculator 330.

[0094] The touch signal supply circuit 310 may provide a touch driving voltage Vd as a touch driving signal to the touch electrodes 140 of the display panel 100 in response to the synchronization signal Tsync.

[0095] The sensing circuit 320 may sense a current signal Isen corresponding to a change in capacitance of the touch electrode 140 of the display panel 100 and may provide a voltage signal Vsen corresponding to the current signal Isen to the touch calculator 330. For example, the sensing circuit 320 may include at least one integrator.

[0096] The touch calculator 330 may convert the voltage signal Vsen, which is analog data, into a voltage signal Vsen, which is a digital signal. The touch calculator 330 may calculate coordinate data TDATA based on the voltage signal Vsen, which is a digital signal. In this regard, the coordinate data TDATA may include the coordinates of each of the first touch point P1 and the second touch point P2, and the touch intensity at each of the first touch point P1 and the second touch point P2.

[0097] The touch driving circuit 300 may provide the calculated coordinate data TDATA to the host system 210. The host system 210 may execute an application program related to the coordinate data TDATA.

[0098] A more detailed description of the multi-touch coordinate calculations performed by the touch drive circuit 300 follows.

[0099] like Figure 3 As shown, the first to fourth switches sw1, sw2, sw3, and sw4 may be connected to the four corners of the touch electrode 140 having a sheet resistance, respectively. The first to fourth touch driving circuits 300a, 300b, 300c, and 300d having touch driving signal supply and touch sensing functions may be connected to the first to fourth switches sw1, sw2, sw3, and sw4, respectively.

[0100] Assuming that an object such as a finger or a touch pen touches the first touch point P1 and the second touch point P2, the corresponding resistance values of the corresponding paths from the first touch point P1 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d can be expressed as r11, r12, r13, and r14, respectively. The corresponding resistance values of the corresponding paths from the second touch point P2 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d can be expressed as r21, r22, r23, and r24, respectively.

[0101] In this regard, as described above, in a touch electrode 140 having a specific sheet resistance, each of the corresponding resistance values r11, r12, r13, and r14 of the corresponding paths from the first touch point P1 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d, and the corresponding resistance values r21, r22, r23, and r24 of the corresponding paths from the second touch point P2 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d can be pre-set based on the sheet resistance of the touch electrode 140. That is, all of the corresponding resistance values of the corresponding paths from each coordinate of all positions on the touch electrode 140 to the first measurement position a, the second measurement position b, the third measurement position c, and the fourth measurement position d can be pre-set based on the sheet resistance of the touch electrode 140. That is, all of the resistance values can be pre-stored in a mapping table between resistance and position in the touch drive circuit 300.

[0102] Thus, when the first coordinates (x1, y1) of the first touch point P1 and the second coordinates (x2, y2) of the second touch point P2 are known to the touch driving circuit, the corresponding resistance values r11, r12, r13, and r14 and the corresponding resistance values r21, r22, r23, and r24 can be obtained from the mapping table by the touch driving circuit 300.

[0103] When the object touches the first touch point P1 , the value of the first finger capacitor Cf1 based on the touch on the first touch point P1 may be calculated according to the sum of current values at four corners of the touch electrode.

[0104] When the object touches the second touch point P2 , the value of the second finger capacitor Cf2 based on the touch on the second touch point P2 may be calculated according to the sum of current values at the four corners of the touch electrode.

[0105] When an object simultaneously touches a first touch point P1 and a second touch point P2, the value Cf1-Cf2 of the finger capacitors based on a multi-touch on the first and second touch points P1 and P2 can be calculated by subtracting the value of the second finger capacitor Cf2 from the value of the first finger capacitor Cf1. In this regard, the first coordinates (x1, y1) of the first touch point P1 and the second coordinates (x2, y2) of the second touch point P2 can be calculated based on five variables.

[0106] Generally speaking, the coordinates of n multi-touch points can be calculated based on 3n-1 independent variables.

[0107] When the object touches the first touch point P1 and the second touch point P2 at the same time, each of the corresponding resistance values r11, r12, r13 and r14 of the corresponding paths from the first touch point P1 to the first measurement position a, the second measurement position b, the third measurement position c and the fourth measurement position d, and the corresponding resistance values r21, r22, r23 and r24 of the corresponding paths from the second touch point P2 to the first measurement position a, the second measurement position b, the third measurement position c and the fourth measurement position d can be obtained from the mapping table by the touch drive circuit 300 as described above.

[0108] Reference Figure 3 , when the object touches the first touch point P1, the sum Q1 of the sensing values sensed at the four corners of the touch electrode can be calculated based on Equation 1:

[0109] Equation 1

[0110] Q1 = Cf1*Vd = Q1a + Q1b + Q1c+ Q1d

[0111] Wherein, Q1 represents the sum of the sensed values sensed at the four corners of the touch electrode based on the touch on the first touch point P1; Vd is the touch drive voltage; Cf1 represents the capacitance value of the finger capacitor based on the touch on the first touch point P1; Q1a, Q1b, Q1c and Q1d represent the values sensed at the first measurement position a, the second measurement position b, the third measurement position c and the fourth measurement position d, respectively, based on the touch on the first touch point P1.

[0112] Since the value sensed at each corner of the touch electrode is inversely proportional to each corresponding resistance (Q=I*t=Vd / r*t), Q1a, Q1b, Q1c, and Q1d can be calculated as follows:

[0113] Equation 2

[0114] Q1a=Q1*(1 / r11) / (1 / r11+1 / r12+1 / r13+1 / r14)

[0115] Q1b=Q1*(1 / r12) / (1 / r11+1 / r12+1 / r13+1 / r14)

[0116] Q1c=Q1*(1 / r13) / (1 / r11+1 / r12+1 / r13+1 / r14)

[0117] Q1d=Q1*(1 / r14) / (1 / r11+1 / r12+1 / r13+1 / r14)

[0118] When the object touches the second touch point P2, the sum Q2 of the sensing values sensed at the four corners of the touch electrode can be calculated based on Equation 3:

[0119] Equation 3

[0120] Q2 = Cf2*Vd = Q2a + Q2b + Q2c+ Q2d

[0121] Wherein, Q2 represents the sum of the sensed values sensed at the four corners of the touch electrode based on the touch on the second touch point P2; Vd is the touch drive voltage; Cf2 represents the capacitance value of the finger capacitor based on the touch on the second touch point P2; Q2a, Q2b, Q2c and Q2d respectively represent the values sensed at the first measurement position a, the second measurement position b, the third measurement position c and the fourth measurement position d based on the touch on the second touch point P2.

[0122] Since the value sensed at each corner of the touch electrode is inversely proportional to each corresponding resistance (Q=I*t=Vd / r*t), Q2a, Q2b, Q2c, and Q2d can be calculated as follows:

[0123] Equation 4

[0124] Q2a=Q2*(1 / r21) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0125] Q2b=Q2*(1 / r22) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0126] Q2c=Q2*(1 / r23) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0127] Q2d=Q2*(1 / r24) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0128] When an object touches the first touch point P1 and the second touch point P2 simultaneously, the sensed value sensed at each of the four corners of the touch electrode can be calculated as the sum of the sensed value sensed at each of the four corners of the touch electrode based on the touch on the first touch point P1 and the sensed value sensed at each of the four corners of the touch electrode based on the touch on the second touch point P2. Thus, when the object touches the first touch point P1 and the second touch point P2 simultaneously, the sensed values Qa, Qb, Qc, and Qd sensed at each of the four corners of the touch electrode can be calculated based on Equation 5:

[0129] Equation 5

[0130] Qa=Q1a+Q2a=Q1(1 / r11) / (1 / r11+1 / r12+1 / r13+1 / r14)+Q2(1 / r21) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0131] Qb=Q1b+Q2b=Q1(1 / r12) / (1 / r11+1 / r12+1 / r13+1 / r14)+Q2(1 / r22) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0132] Qc=Q1c+Q2c=Q1(1 / r13) / (1 / r11+1 / r12+1 / r13+1 / r14)+Q2(1 / r23) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0133] Qd=Q1d+Q2d=Q1(1 / r14) / (1 / r11+1 / r12+1 / r13+1 / r14)+Q2(1 / r24) / (1 / r21+1 / r22+1 / r23+1 / r24)

[0134] Next, when the third switch sw3 and the fourth switch sw4 are turned off and the object touches the first touch point P1, sensing is performed only at the first measurement position a and the second measurement position b. Thus, the sum Q1 of the sensing values measured at the first measurement position a and the second measurement position b based on the touch on the first touch point P1 can be calculated as follows:

[0135] Equation 6

[0136] Q1 = Cf1*Vd = Q1a + Q1b

[0137] Q1a = Q1*(1 / r11) / (1 / r11+1 / r12)

[0138] Q1b = Q1*(1 / r12) / (1 / r11+1 / r12)

[0139] Next, when the third switch sw3 and the fourth switch sw4 are turned off and the object touches the first touch point P1 and the second touch point P2 at the same time, the sum Q of the sensed values sensed at the first measurement position a and the second measurement position b based on the touches on the first touch point P1 and the second touch point P2, respectively, can be calculated as follows:

[0140] Equation 7

[0141] Q = Q1 + Q2 = Cf1*Vd + Cf2*Vd

[0142] Qa = Q1a + Q1b = Q1*(1 / r11) / (1 / r11+1 / r12) + Q2*(1 / r21) / (1 / r21+1 / r22)

[0143] Qb = Q1b + Q2b = Q1*(1 / r12) / (1 / r11+1 / r12) + Q2*(1 / r22) / (1 / r21+1 / r22)

[0144] Therefore, based on the above equations 5 and 7, when the object touches the first touch point P1 and the second touch point P2 at the same time, the first coordinate value (x1, y1) and the second coordinate value (x2, y2) as well as the capacitance value of the finger capacitor Cf can be calculated by the touch driving circuit 300.

[0145] Figure 5 is a graph showing measurement positions and the number of measurement values in the on and off states of a switch circuit in a touch display device according to an embodiment of the present invention.

[0146] like Figure 5 As shown in the figure, by measuring the sensed values at four measurement positions a, b, c, and d while changing the off switch, 28 sensed values can be obtained. Thus, coordinate data for up to nine simultaneous multi-touch points can be calculated based on these 28 sensed values. In other words, based on the 3n-1 law, when n = 9, at least 26 values are required. In this regard, 28 is greater than 26, allowing coordinate data for up to nine simultaneous multi-touch points to be obtained. However, when n = 10, at least 29 sensed values are required. However, 28 is less than 29.

[0147] Therefore, in order to improve the accuracy of coordinate calculation of touch points or increase the number of touch points whose coordinate data can be calculated simultaneously, four additional touch driving circuits may be further included, which may correspond to the four median points between the four corners of the touch electrode 140. Figure 10 Shown in.

[0148] In one example, the method of obtaining the coordinate values of the touch points from the above equation can be performed by numerical analysis. Alternatively, the accuracy of calculating the coordinate values of the touch points from the above equation can be improved by using machine learning techniques that have been widely adopted recently.

[0149] Figure 6 An equivalent circuit based on the sheet resistance at the coordinates of each of all positions on the touch electrodes in the touch display device according to the embodiment of the present invention is shown. Figure 7 Shows when the object only touches Figure 6 The measurement result of the first touch point P1 in . Figure 8 Shows when the object only touches Figure 6 The measurement result of the second touch point P2 in . Figure 9 Shows when objects touch simultaneously Figure 6 The measurement results of the first touch point P1 and the second touch point P2.

[0150] The touch electrode has a sheet resistance. The finger capacitance of the touch on the first touch point P1 is 1.7 pF. The finger capacitance of the touch on the second touch point P2 is 1 pF. Therefore, when a driving voltage of 10 V is applied to the touch electrode, the values measured at the corners of the touch electrode are shown in FIG. Figure 9 Shown in.

[0151] It can be recognized that when the object touches the first touch point P1 and the second touch point P2 at the same time, each of the values measured at the corners a, b, c and d of the touch electrode is equivalent to the sum of the values measured at each of the corners a, b, c and d based on the touch on the first touch point P1 and the values measured at each of the corners a, b, c and d based on the touch on the second touch point P2.

[0152] In one example, coordinate calculation of multi-touch points as described above may be implemented using a touch driving power supply, an amplifier, and a switch connected to each corner of a touch electrode implemented as a cathode of an organic light emitting diode (OLED) panel via each touch wiring.

[0153] Alternatively, the coordinate calculation of multiple touch points as described above can be implemented using a configuration in which touch electrodes are provided on or below an organic light emitting diode panel, and a touch driving power supply, amplifier, and switch are connected to each corner of the touch electrodes via each wiring.

[0154] In addition, modulating the touch drive voltage may include a mechanism in which a dummy electrode (shielding electrode) may be formed between the touch electrode and the display electrode, and a voltage across the dummy electrode and the touch electrode may be modulated, or a voltage across the touch electrode and the display electrode may be modulated.

[0155] Figure 10 is a diagram illustrating multi-touch sensing in a touch display device according to another embodiment of the present invention.

[0156] Reference Figure 10 The touch display device includes first to eighth switching circuits sw1, sw2, sw3, sw4, sw5, sw6, sw7 and sw8 and first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g and 300h.

[0157] The first to eighth switches or switch circuits sw1, sw2, sw3, sw4, sw5, sw6, sw7, and sw8 may be respectively connected to eight measurement positions of the touch electrode 140 of the display panel 100. The touch electrode includes four corners, four sides, and four corresponding midpoints of the four sides, wherein the measurement positions include the first to eighth measurement positions corresponding to the four corners and the four midpoints.

[0158] Each of the first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g and 300h may apply a touch driving signal to the touch electrode 140 via each of the first to eighth switches sw1, sw2, sw3, sw4, sw5, sw6, sw7 and sw8, and may receive each of the sensing values sensed at the first to eighth measurement positions, respectively, in response to each of the first to eighth switches sw1, sw2, sw3, sw4, sw5, sw6, sw7 and sw8 being turned on.

[0159] Furthermore, the touch drive circuit 300 may be configured to calculate the coordinates of the multi-touch points on the touch electrodes (e.g., the coordinates of the first touch point P1 and the second touch point P2) based on the sensed values sensed at each of the first to eighth measurement positions a to h. For example, the first to eighth touch drive circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g, and 300h may apply touch drive signals to the first to eighth measurement positions a to h and sense the sensed currents at the first to eighth measurement positions a to h.

[0160] In one example, during a touch period, all of the first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g, and 300h are configured to: turn on all of the first to eighth switches sw1, sw2, sw3, sw4, sw5, sw6, sw7, and sw8, respectively, and obtain sensed values sensed at all of the corresponding first to eighth measurement locations a to h, respectively, connected thereto. For example, the first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g, and 300h may sense the sense currents at the first to fourth measurement locations a to d by turning on the first to fourth switches sw1, sw2, sw3, and sw4 and turning off the fifth to eighth switches sw5, sw6, sw7, and sw8.

[0161] In addition, the first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g, and 300h can sense the sense currents at the fifth to eighth measurement locations e to h by turning off the first to fourth switches sw1, sw2, sw3, and sw4 and turning on the fifth to eighth switches sw5, sw6, sw7, and sw8. In this manner, the first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g, and 300h can sense at least one sense current at the corresponding measurement location by turning on or off at least one of the first to eighth switches sw1, sw2, sw3, sw4, sw5, sw6, sw7, and sw8.

[0162] In another example, during a touch period, at least one of the first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g, and 300h is configured to: turn on corresponding at least one of the first to eighth switches sw1, sw2, sw3, sw4, sw5, sw6, sw7, and sw8 and obtain at least one sensing value sensed at corresponding at least one of the measurement positions a to h connected thereto, wherein during the touch period, each of the remaining touch driving circuits of the first to eighth touch driving circuits 300a, 300b, 300c, 300d, 300e, 300f, 300g, and 300h is configured to: turn off each of the remaining switches of the first to eighth switches sw1, sw2, sw3, sw4, sw5, sw6, sw7, and sw8.

[0163] In this regard, the touch drive circuit 300 may be configured to calculate coordinates of multiple touch points on the touch electrode (e.g., coordinates of the first touch point P1 and the second touch point P2) based on all of the corresponding sensed values at the first to eighth measurement positions a to h, the sensed values at one or more of the first to eighth measurement positions a to h, the corresponding resistance values R11, R12, R13, R14, R15, R16, R17, and R18 of the corresponding paths from the first touch point P1 to the first to eighth measurement positions a to h, and the corresponding resistance values R21, R22, R23, R24, R25, R26, R27, and R28 of the corresponding paths from the second touch point P2 to the first to eighth measurement positions a to h.

[0164] According to an embodiment of a touch display device, touch performance may be improved by detecting multi-touch in a touch sensing mechanism for sensing a change in capacitance of a touch electrode.

[0165] Furthermore, the touch sensor can detect multiple touches on a single electrode, thereby reducing the manufacturing cost of the touch panel.

[0166] Furthermore, when the touch panel is combined with the display panel, the brightness and clarity of the displayed image can be maintained.

[0167] In addition, the production energy of the touch panel can be reduced and the touch panel process can be optimized.

[0168] A touch display device according to various aspects and embodiments of the present invention can be described as follows.

[0169] A first aspect of the present invention provides a touch display device, comprising: a display panel, the display panel including touch electrodes having multiple measurement positions; a switching circuit connected to each measurement position of the touch electrodes; and a touch drive circuit connected to each measurement position of the touch electrodes via the switching circuit, wherein the touch drive circuit is configured to apply a touch drive signal to the touch electrodes, receive a sensing value from the measurement position based on the operation of the switching circuit, and calculate the coordinates of multiple touch points on the touch electrodes based on the sensing values.

[0170] According to some embodiments of the first aspect of the touch display device, the touch drive circuit is configured to calculate the coordinates of the multiple touch points on the touch electrode based on all of the sensed values sensed at the measurement positions, the sensed values sensed at at least one of the measurement positions, and the resistance values of the corresponding paths between the measurement positions and each of the multiple touch points.

[0171] According to some embodiments of the first aspect of the touch display device, a resistance value of a corresponding path between the measurement position and each of all touch positions on the touch electrode is pre-set in the touch drive circuit based on a sheet resistance value of the touch electrode.

[0172] According to some embodiments of the first aspect of the touch display device, the measurement position includes a corner of the touch electrode.

[0173] According to some embodiments of the first aspect of the touch display device, the touch electrode includes a first corner, a second corner, a third corner and a fourth corner, the measurement position includes a first measurement position as the first corner, a second measurement position as the second corner, a third measurement position as the third corner and a fourth measurement position as the fourth corner, wherein the switching circuit includes a first switch, a second switch, a third switch and a fourth switch respectively connected to the first measurement position, the second measurement position, the third measurement position and the fourth measurement position, wherein the touch drive circuit includes a first touch drive circuit, a second touch drive circuit, a third touch drive circuit and a fourth touch drive circuit respectively connected to the first measurement position, the second measurement position, the third measurement position and the fourth measurement position via the first switch, the second switch, the third switch and the fourth switch.

[0174] According to some embodiments of the first aspect of the touch display device, during a touch period, one of the first touch drive circuit, the second touch drive circuit, the third touch drive circuit and the fourth touch drive circuit is configured to: turn on a corresponding one of the first switch, the second switch, the third switch and the fourth switch, and obtain a sensing value sensed at a measurement position connected to the turned-on switch; wherein during the touch period, each of the remaining touch drive circuits of the first touch drive circuit, the second touch drive circuit, the third touch drive circuit and the fourth touch drive circuit is configured to: turn off each of the remaining switches of the first switch, the second switch, the third switch and the fourth switch.

[0175] According to some embodiments of the first aspect of the touch display device, during a touch period, two touch drive circuits among the first touch drive circuit, the second touch drive circuit, the third touch drive circuit, and the fourth touch drive circuit are configured to: respectively turn on corresponding two switches among the first switch, the second switch, the third switch, and the fourth switch, and obtain sensing values sensed at corresponding two measurement positions respectively connected to the turned-on switches; wherein during the touch period, each of the remaining two touch drive circuits among the first touch drive circuit, the second touch drive circuit, the third touch drive circuit, and the fourth touch drive circuit is configured to: respectively turn off each of the remaining two switches among the first switch, the second switch, the third switch, and the fourth switch.

[0176] According to some embodiments of the first aspect of the touch display device, during a touch period, all of the first touch drive circuit, the second touch drive circuit, the third touch drive circuit, and the fourth touch drive circuit are configured to: respectively turn on all of the first switch, the second switch, the third switch, and the fourth switch, and obtain sensing values sensed at all of the corresponding measurement positions respectively connected to the turned-on switches.

[0177] According to some embodiments of the first aspect of the touch display device, the touch drive circuit is configured to: calculate the coordinates of the multiple touch points on the touch electrode based on the corresponding sensed values at the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position; the sensed values sensed at the first measurement position and the second measurement position, respectively, when the first switch and the second switch are turned on and the third switch and the fourth switch are turned off; the sensed values sensed at the third measurement position and the fourth measurement position, respectively, when the first switch and the second switch are turned off and the third switch and the fourth switch are turned on; the corresponding resistance values of the corresponding paths from the first touch point to the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position; and all of the corresponding resistance values of the corresponding paths from the second touch point to the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position.

[0178] According to some embodiments of the first aspect of the touch display device, the measurement positions include a plurality of corners of the touch electrode and intermediate points between adjacent corners of the plurality of corners.

[0179] According to some embodiments of the first aspect of the touch display device, the display panel includes: a display panel layer, in which a plurality of sub-pixels are formed; and a touch panel layer arranged on the display panel layer, wherein the touch panel layer includes: a shielding electrode layer formed on top of the display panel layer; a covering layer formed on top of the shielding electrode layer; an optically transparent adhesive layer formed on top of the covering layer; and the touch electrode formed on top of the optically transparent adhesive layer.

[0180] According to some embodiments of the first aspect of the touch display device, the touch electrode is formed as a monolithic electrode covering a touch area of the display panel.

[0181] According to some embodiments of the first aspect of the touch display device, the touch display device further includes: a shielding electrode driver, which is configured to apply a modulated signal having the same period and amplitude as the touch drive signal to the shielding electrode layer during a touch period.

[0182] According to some embodiments of the first aspect of the touch display device, the touch display device also includes a power supply circuit, the display panel is configured to operate in a time-division manner in a display period for displaying an image and a touch period for detecting touch, and the power supply circuit is configured to apply a high potential power supply voltage and a low potential power supply voltage to the high potential power supply terminal and the low potential power supply terminal of each sub-pixel via a power line during the display period; and during the touch period, apply a modulated high potential power supply voltage and a modulated low potential power supply voltage having the same period and amplitude as the touch drive signal applied to the touch electrode to the high potential power terminal and the low potential power terminal respectively.

[0183] According to some embodiments of the first aspect of the touch display device, the touch drive circuit includes: a touch signal supply circuit, which provides a touch drive voltage as the touch drive signal to the touch electrode in response to a synchronization signal; a sensing circuit, which senses a current signal corresponding to a change in capacitance of the touch electrode and provides a voltage signal corresponding to the current signal to a touch calculator; and the touch calculator, which calculates coordinate data based on the voltage signal as a digital signal, the coordinate data including the coordinates of each of the multiple touch points and the touch intensity at each of the multiple touch points.

[0184] According to some embodiments of the first aspect of the touch display device, a mapping table between resistance and position is provided in the touch drive circuit, and the resistance value is pre-stored in the mapping table.

[0185] A second aspect of the present invention provides a touch display device, comprising: a display panel including touch electrodes and configured to operate in a time-division manner in a display period for displaying an image and a touch period for detecting a touch; a first switching circuit, a second switching circuit, a third switching circuit, and a fourth switching circuit, respectively connected to a first measurement position, a second measurement position, a third measurement position, and a fourth measurement position corresponding to four corners of the touch electrodes; and a touch drive circuit, the touch drive circuit connected to each of the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position of the touch electrodes via each of the first switching circuit, the second switching circuit, the third switching circuit, and the fourth switching circuit, wherein during the touch period, the touch drive circuit is configured to apply a touch drive signal to the touch electrodes, receive sensed values from the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position based on the operation of the first switching circuit, the second switching circuit, the third switching circuit, and the fourth switching circuit, and calculate coordinates of multiple touch points on the touch electrodes based on the sensed values.

[0186] According to some embodiments of the second aspect of the touch display device, the touch electrode is formed as a monolithic electrode covering a touch area of the display panel.

[0187] According to some embodiments of the second aspect of the touch display device, the display panel includes: a display panel layer, in which a plurality of sub-pixels are formed; and a touch panel layer arranged on the display panel layer, wherein the touch panel layer includes: a shielding electrode layer formed on top of the display panel layer; a covering layer formed on top of the shielding electrode layer; an optically transparent adhesive layer formed on top of the covering layer; and the touch electrode formed on top of the optically transparent adhesive layer.

[0188] According to some embodiments of the second aspect of the touch display device, the touch display device also includes a power supply circuit, which is configured to apply a high potential power supply voltage and a low potential power supply voltage to the high potential power supply terminal and the low potential power supply terminal of each sub-pixel via a power line during the display period; and during the touch period, apply a modulated high potential power supply voltage and a modulated low potential power supply voltage having the same period and amplitude as the touch drive signal applied to the touch electrode to the high potential power terminal and the low potential power terminal respectively.

[0189] A third aspect of the present invention provides a touch display device, comprising: a display panel, the display panel including a touch electrode having multiple measurement positions; a switching circuit connected to each measurement position of the touch electrode; and a touch drive circuit connected to each measurement position of the touch electrode via the switching circuit, wherein the touch drive circuit is configured to apply a touch drive signal to the touch electrode, receive a sensing value from the measurement position based on the operation of the switching circuit, and calculate the coordinates of multiple touch points on the touch electrode based on the sensing value, wherein the touch electrode includes four corners and four middle points of the corresponding four sides, and wherein the measurement positions include first to eighth measurement positions corresponding to the four corners and the four middle points.

[0190] According to some embodiments of the third aspect of the touch display device, the switching circuit includes first to eighth switches respectively connected to the first to eighth measurement positions, wherein the touch drive circuit includes first to eighth touch drive circuits respectively connected to the first to eighth measurement positions via the first to eighth switches.

[0191] According to some embodiments of the third aspect of the touch display device, during a touch period, all of the first to eighth touch drive circuits are configured to respectively turn on all of the first to eighth switches, and obtain sensing values sensed at all of the corresponding first to eighth measurement positions respectively connected to the turned-on switches.

[0192] According to some embodiments of the third aspect of the touch display device, during a touch period, at least one of the first to eighth touch drive circuits is configured to turn on a corresponding at least one of the first to eighth switches and obtain at least one sensing value sensed at a corresponding at least one measurement position connected to the turned-on switch; wherein during the touch period, each of the remaining touch drive circuits in the first to eighth touch drive circuits is configured to turn off each of the remaining switches in the first to eighth switches.

[0193] According to some embodiments of the third aspect of the touch display device, the display panel includes: a display panel layer, in which a plurality of sub-pixels are formed; and a touch panel layer arranged on the display panel layer, wherein the touch panel layer includes: a shielding electrode layer formed on top of the display panel layer; a covering layer formed on top of the shielding electrode layer; an optically transparent adhesive layer formed on top of the covering layer; and the touch electrode formed on top of the optically transparent adhesive layer.

[0194] According to some embodiments of the third aspect of the touch display device, the touch display device also includes a shielding electrode driver, which is configured to apply a modulated signal having the same period and amplitude as the touch drive signal to the shielding electrode layer during a touch period.

[0195] According to some embodiments of the third aspect of the touch display device, the touch electrode is formed as a monolithic electrode covering a touch area of the display panel.

[0196] According to some embodiments of the third aspect of the touch display device, the touch display device also includes a power supply circuit, the display panel is configured to operate in a time-division manner in a display period for displaying an image and a touch period for detecting touch, and the power supply circuit is configured to apply a high potential power supply voltage and a low potential power supply voltage to the high potential power supply terminal and the low potential power supply terminal of each sub-pixel via a power line during the display period; and during the touch period, apply a modulated high potential power supply voltage and a modulated low potential power supply voltage having the same period and amplitude as the touch drive signal applied to the touch electrode to the high potential power terminal and the low potential power terminal respectively.

[0197] Although the embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments, but can be implemented in various forms. Those skilled in the art will recognize that the present invention can be practiced in other specific forms without changing the technical spirit or essential characteristics of the present invention. Therefore, it should be understood that the above-described embodiments are not restrictive, but are illustrative in all aspects.

Claims

1. A touch display device, comprising: a display panel comprising a touch electrode having a plurality of measurement positions; a switch circuit connected to each measurement position of the touch electrode; as well as a touch drive circuit connected to each measurement position of the touch electrode via the switch circuit, The touch driving circuit is configured as follows: applying a touch drive signal to the touch electrode; receiving a sensed value from the measurement location based on operation of the switching circuit; and Coordinates of multiple touch points on the touch electrodes are calculated based on the sensing values.

2. The touch display device according to claim 1 , wherein the touch drive circuit is configured to calculate the coordinates of the multi-touch points on the touch electrode based on all of the sensed values sensed at the measurement positions, the sensed values sensed at at least one of the measurement positions, and the resistance values of the corresponding paths between the measurement positions and each of the multi-touch points.

3. The touch display device according to claim 2 , wherein a resistance value of a corresponding path between the measurement position and each of all touch positions on the touch electrode is preset in the touch drive circuit based on a sheet resistance value of the touch electrode. The touch display device according to claim 1 , wherein the measurement position includes a corner of the touch electrode.

5. The touch display device according to claim 4 , wherein the touch electrode includes a first corner, a second corner, a third corner, and a fourth corner, and the measurement position includes a first measurement position as the first corner, a second measurement position as the second corner, a third measurement position as the third corner, and a fourth measurement position as the fourth corner. wherein the switch circuit comprises a first switch, a second switch, a third switch and a fourth switch connected to the first measurement position, the second measurement position, the third measurement position and the fourth measurement position respectively; The touch drive circuit includes a first touch drive circuit, a second touch drive circuit, a third touch drive circuit and a fourth touch drive circuit respectively connected to the first measurement position, the second measurement position, the third measurement position and the fourth measurement position via the first switch, the second switch, the third switch and the fourth switch.

6. The touch display device according to claim 5 , wherein during a touch period, one of the first touch drive circuit, the second touch drive circuit, the third touch drive circuit, and the fourth touch drive circuit is configured to: turn on a corresponding one of the first switch, the second switch, the third switch, and the fourth switch, and obtain a sensed value sensed at a measurement position connected to the turned-on switch; During the touch period, each of the remaining touch drive circuits among the first touch drive circuit, the second touch drive circuit, the third touch drive circuit and the fourth touch drive circuit is configured to: turn off each of the remaining switches among the first switch, the second switch, the third switch and the fourth switch.

7. The touch display device according to claim 5 , wherein during a touch period, two of the first, second, third, and fourth touch drive circuits are configured to: turn on corresponding two of the first, second, third, and fourth switches, respectively, and obtain sensed values sensed at corresponding two measurement positions connected to the turned-on switches, respectively; During the touch period, each of the remaining two touch drive circuits among the first touch drive circuit, the second touch drive circuit, the third touch drive circuit and the fourth touch drive circuit is configured to: turn off each of the remaining two switches among the first switch, the second switch, the third switch and the fourth switch.

8. The touch display device according to claim 5, wherein during a touch period, all of the first touch drive circuit, the second touch drive circuit, the third touch drive circuit, and the fourth touch drive circuit are configured to: respectively turn on all of the first switches, the second switches, the third switches, and the fourth switches, and obtain sensing values sensed at all of the corresponding measurement positions respectively connected to the turned-on switches.

9. The touch display device according to claim 5, wherein the touch driving circuit is configured to: based on corresponding sensing values at the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position; sensing values sensed at the first measurement position and the second measurement position, respectively, when the first switch and the second switch are turned on and the third switch and the fourth switch are turned off; sensing values sensed at the third measurement position and the fourth measurement position, respectively, when the first switch and the second switch are turned off and the third switch and the fourth switch are turned on; respective resistance values of respective paths from the first touch point to the first measurement location, the second measurement location, the third measurement location, and the fourth measurement location; and all of the corresponding resistance values of the corresponding paths from the second touch point to the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position, and calculate the coordinates of the multi-touch points on the touch electrode. 10 . The touch display device according to claim 1 , wherein the measurement positions include a plurality of corners of the touch electrode and intermediate points between adjacent corners among the plurality of corners.

11. The touch display device according to claim 1 , wherein the display panel comprises: a display panel layer, wherein a plurality of sub-pixels are formed in the display panel layer; as well as A touch panel layer is provided on the display panel layer, The touch panel layer comprises: a shielding electrode layer formed on top of the display panel layer; forming a capping layer on top of the shield electrode layer; an optically clear adhesive layer formed on top of the cover layer; and The touch electrode is formed on top of the optically transparent adhesive layer. 12 . The touch display device according to claim 11 , wherein the touch electrode is formed as a single-piece electrode covering a touch area of the display panel.

13. The touch display device according to claim 11, further comprising: A shielding electrode driver is configured to apply a modulated signal having the same period and amplitude as those of the touch driving signal to the shielding electrode layer during a touch period.

14. A touch display device, comprising: a display panel including a touch electrode and configured to operate in a time-division manner in a display period for displaying an image and a touch period for detecting a touch; a first switch circuit, a second switch circuit, a third switch circuit, and a fourth switch circuit respectively connected to a first measurement position, a second measurement position, a third measurement position, and a fourth measurement position corresponding to four corners of the touch electrode; as well as a touch drive circuit connected to each of the first measurement position, the second measurement position, the third measurement position, and the fourth measurement position of the touch electrode via each of the first switch circuit, the second switch circuit, the third switch circuit, and the fourth switch circuit; During the touch period, the touch driving circuit is configured to: applying a touch drive signal to the touch electrode; receiving sensed values from the first, second, third, and fourth measurement locations based on operations of the first, second, third, and fourth switching circuits; and Coordinates of multiple touch points on the touch electrodes are calculated based on the sensing values.

15. A touch display device, comprising: a display panel comprising a touch electrode having a plurality of measurement positions; a switch circuit connected to each measurement position of the touch electrode; as well as a touch drive circuit connected to each measurement position of the touch electrode via the switch circuit, The touch driving circuit is configured as follows: applying a touch drive signal to the touch electrode; receiving a sensed value from the measurement location based on operation of the switching circuit; and Calculating the coordinates of multiple touch points on the touch electrodes based on the sensing values, The touch electrode includes four corners and four middle points of the corresponding four sides, The measurement positions include first to eighth measurement positions corresponding to the four corners and the four intermediate points.

16. The touch display device according to claim 15, wherein the switch circuit comprises first to eighth switches connected to the first to eighth measurement positions, respectively. The touch driving circuit includes first to eighth touch driving circuits connected to the first to eighth measuring positions via the first to eighth switches, respectively.

17. The touch display device according to claim 16 , wherein during a touch period, all of the first to eighth touch driving circuits are configured to respectively turn on all of the first to eighth switches, and obtain sensing values sensed at all of the corresponding first to eighth measurement positions respectively connected to the turned-on switches.

18. The touch display device according to claim 16 , wherein during a touch period, at least one of the first to eighth touch driving circuits is configured to turn on corresponding at least one of the first to eighth switches, and obtain at least one sensing value sensed at corresponding at least one measurement position connected to the turned-on switch, During the touch period, each of the remaining touch driving circuits among the first to eighth touch driving circuits is configured to turn off each of the remaining switches among the first to eighth switches.

19. The touch display device according to claim 15, wherein the display panel comprises: a display panel layer, wherein a plurality of sub-pixels are formed in the display panel layer; as well as A touch panel layer is provided on the display panel layer, The touch panel layer comprises: a shielding electrode layer formed on top of the display panel layer; forming a capping layer on top of the shield electrode layer; an optically clear adhesive layer formed on top of the cover layer; and The touch electrode is formed on top of the optically transparent adhesive layer.

20. The touch display device according to claim 19, wherein the touch display device further comprises a shielding electrode driver configured to apply a modulated signal having the same period and amplitude as those of the touch drive signal to the shielding electrode layer during a touch period.

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