Patent Publication Number: US-11640220-B2

Title: Touch sensing unit and display device including the same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/792,876, filed on Feb. 17, 2020, which claims priority from and the benefit of Korean Patent Application No. 10-2019-0029935, filed on Mar. 15, 2019, each of which is hereby incorporated by reference for all purposes as if fully set forth herein. 
    
    
     BACKGROUND 
     Field 
     Exemplary embodiments of the invention relate generally to a touch sensing unit and a display device including the same. 
     Discussion of the Background 
     An electronic device such as a smartphone, a tablet personal computer (PC), a digital camera, a notebook computer, a navigation device, or a television (TV) that provides images to a user includes a display device. The display device may include a display panel for generating and displaying an image and various input devices. 
     A touch sensing unit capable of recognizing touch input has been widely used as the input device of a display device, particularly in a smartphone or a tablet PC. The touch sensing unit detects the presence of touch input and calculates the location of touch input as touch input coordinates. 
     The above information disclosed in this Background section is only for understanding of the background of the inventive concepts, and, therefore, it may contain information that does not constitute prior art. 
     SUMMARY 
     A touch sensing unit constructed according to exemplary embodiments of the invention and a display device including the same have an improved touch sensitivity. 
     Additional features of the inventive concepts will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the inventive concepts. 
     A touch sensing unit according to an exemplary embodiment includes a touch sensing area having long sides and short sides, first touch electrodes arranged in the touch sensing area along the long sides of the touch sensing area, second touch electrodes arranged in the touch sensing area along the short sides of the touch sensing area, first connecting electrodes electrically connecting the first touch electrodes, and second connecting electrodes electrically connecting the second touch electrodes, in which a thickness of the second connecting electrodes is different from thicknesses of the first touch electrodes and the second touch electrodes, respectively. 
     A display unit according to another exemplary embodiment includes a display area, and a touch sensing unit including a touch sensing area overlapping the display area, the touch sensing area having long sides and short sides, in which the touch sensing unit includes first touch electrodes arranged along the long sides of the touch sensing area, second touch electrodes arranged along the short sides of the touch sensing area, first connecting electrodes electrically connecting the first touch electrodes, and second connecting electrodes electrically connecting the second touch electrodes, and a thickness of the second connecting electrodes is different from thicknesses of the first touch electrodes and the second touch electrodes, respectively. 
     A touch sensing unit according to an exemplary embodiment includes a touch sensing area having long sides and short sides, first touch electrodes arranged in the touch sensing area along the long sides of the touch sensing area, second touch electrodes arranged in the touch sensing area along the short sides of the touch sensing area, first connecting electrodes electrically connecting the first touch electrodes, and second connecting electrodes electrically connecting the second touch electrodes, in which a thickness of the second connecting electrodes is thinner than a thickness of the first connecting electrodes. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention, and together with the description serve to explain the inventive concepts. 
         FIG.  1    is a perspective view of a display device according to an exemplary embodiment. 
         FIG.  2    is a plan view of the display device of  FIG.  1   . 
         FIG.  3    is a cross-sectional view taken along line I-I′ of  FIG.  2   . 
         FIG.  4    is a layout view of a display unit of  FIG.  3    according to an exemplary embodiment. 
         FIG.  5    is a layout view of a touch sensing unit according to an exemplary embodiment. 
         FIG.  6    is a plan view illustrating the shapes and the arrangement of light-emitting areas and first touch electrodes in an area A of  FIG.  5    according to an exemplary embodiment. 
         FIG.  7    is a cross-sectional view taken along line II-IF of  FIG.  6   . 
         FIG.  8    is an enlarged layout view of an area B of  FIG.  5   . 
         FIG.  9    is an exemplary enlarged layout view of an area B_ 1  of  FIG.  8   . 
         FIG.  10    is another exemplary enlarged layout view of the area B_ 1  of  FIG.  8   . 
         FIG.  11    is a cross-sectional view taken along line of  FIG.  9   . 
         FIG.  12    is a cross-sectional view taken along line IV-IV′ of  FIG.  9   . 
         FIG.  13    is a cross-sectional view taken along line V-V′ of  FIG.  9   . 
         FIG.  14    is a cross-sectional view of an area C of  FIG.  5   . 
         FIG.  15    is a cross-sectional view taken along line VI-VI′ of  FIG.  14   . 
         FIG.  16    is a cross-sectional view taken along line VII-VII′ of  FIG.  14   . 
         FIG.  17    is a layout view of a touch sensing unit according to another exemplary embodiment. 
         FIG.  18    is a layout view of a touch sensing unit according to another exemplary embodiment. 
         FIG.  19    is an exemplary enlarged layout view of an area D of  FIG.  18   . 
         FIG.  20    is another exemplary enlarged layout view of the area D of  FIG.  18   . 
         FIG.  21    is another exemplary enlarged layout view of the area D of  FIG.  18   . 
         FIG.  22    is another exemplary enlarged layout view of the area D of  FIG.  18   . 
         FIG.  23    is another exemplary enlarged layout view of the area D of  FIG.  18   . 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various exemplary embodiments or implementations of the invention. As used herein “embodiments” and “implementations” are interchangeable words that are non-limiting examples of devices or methods employing one or more of the inventive concepts disclosed herein. It is apparent, however, that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various exemplary embodiments. Further, various exemplary embodiments may be different, but do not have to be exclusive. For example, specific shapes, configurations, and characteristics of an exemplary embodiment may be used or implemented in another exemplary embodiment without departing from the inventive concepts. 
     Unless otherwise specified, the illustrated exemplary embodiments are to be understood as providing exemplary features of varying detail of some ways in which the inventive concepts may be implemented in practice. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects, etc. (hereinafter individually or collectively referred to as “elements”), of the various embodiments may be otherwise combined, separated, interchanged, and/or rearranged without departing from the inventive concepts. 
     The use of cross-hatching and/or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, dimensions, proportions, commonalities between illustrated elements, and/or any other characteristic, attribute, property, etc., of the elements, unless specified. Further, in the accompanying drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. When an exemplary embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements. 
     When an element, such as a layer, is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer or intervening elements or layers may be present. When, however, an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. To this end, the term “connected” may refer to physical, electrical, and/or fluid connection, with or without intervening elements. Further, the D1-axis, the D2-axis, and the D3-axis are not limited to three axes of a rectangular coordinate system, such as the x, y, and z-axes, and may be interpreted in a broader sense. For example, the D1-axis, the D2-axis, and the D3-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Although the terms “first,” “second,” etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the disclosure. 
     Spatially relative terms, such as “beneath,” “below,” “under,” “lower,” “above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), and the like, may be used herein for descriptive purposes, and, thereby, to describe one elements relationship to another element(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms, “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is also noted that, as used herein, the terms “substantially,” “about,” and other similar terms, are used as terms of approximation and not as terms of degree, and, as such, are utilized to account for inherent deviations in measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art. 
     Various exemplary embodiments are described herein with reference to sectional and/or exploded illustrations that are schematic illustrations of idealized exemplary embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, exemplary embodiments disclosed herein should not necessarily be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. In this manner, regions illustrated in the drawings may be schematic in nature and the shapes of these regions may not reflect actual shapes of regions of a device and, as such, are not necessarily intended to be limiting. 
     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 disclosure is a part. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein. 
       FIG.  1    is a perspective view of a display device according to an exemplary embodiment.  FIG.  2    is a plan view of the display device of  FIG.  1   . 
     As used herein, the terms “above”, “top”, and “top surface” denote an upward direction with respect to a display panel  100 , i.e., a Z-axis direction, and the terms “below”, “bottom”, and “bottom surface” denote a downward direction with respect to the display panel  100 , i.e., the direction opposite to the Z-axis direction. Also, the terms “left”, “right”, “upper”, and “lower” denote directions as viewed from above the display panel  100 . For example, the term “left” denotes the direction opposite to an X-axis direction, the term “right” denotes the X-axis direction, the term “upper” denotes a Y-axis direction, and the term “lower” denotes the direction opposite to the Y-axis direction. 
     Referring to  FIGS.  1  and  2   , a display device  10 , which displays moving or still images, may be used as a display screen not only for a mobile electronic device (e.g., a mobile phone, a smartphone, a tablet personal computer (PC), a smartwatch, a watch phone, a mobile communication terminal, an electronic notebook, an electronic book, a portable multimedia player (PMP), a navigation device, or an ultra-mobile PC (UMPC)), but also for various other products, such as a television (TV), a notebook computer, a monitor, a billboard, and an Internet of Things (IoT) device. The display device  10  may be one of an organic light-emitting diode (OLED) display device, a liquid crystal display (LCD) device, a plasma display panel (PDP) device, a field emission display (FED) device, an electrophoretic display (EPD) device, an electrowetting display device, a quantum dot light-emitting diode (QLED) display device, and a micro light-emitting diode (mLED) display device. The display device  10  will hereinafter be described as being an OLED display device, but the inventive concepts are not limited thereto. 
     The display device  10  includes the display panel  100 , a display driving circuit  200 , a circuit board  300 , and a touch driving circuit  400 . 
     The display panel  100  may include a main area MA and a protruding area PA that protrudes from one side of the main area MA. 
     The main area MA may be formed as a rectangular plane having a pair of short sides that extend in a first direction (or the X-axis direction) and a pair of long sides that extend in a second direction (or the Y-axis direction) intersecting the first direction (or the X-axis direction. The corners at which the short sides and the long sides of the main area MA meet may be rounded to have a predetermined curvature or may be right-angled. The planar shape of the display device  10  is not particularly limited, and the display device  10  may be formed in various shapes such as a polygonal, circular, or elliptical shape. The main area MA may be formed to be generally flat, but the inventive concepts are not limited thereto. In some exemplary embodiments, the main area MA may have curved parts on both sides thereof, in which case, the curved parts may have a uniform or variable curvature. 
     The main area MA may include a display area DA, in which pixels are formed to display an image, and a non-display area NDA, which is peripheral to the display area DA. 
     In the display area DA, not only the pixels, but also scan lines, data lines, and a power line connected to the pixels, may be disposed. When the main area MA includes curved parts, the display area DA may also be disposed in the curved parts, and in this case, an image displayed by the display panel  100  can be viewed even in the curved parts. 
     The non-display area NDA may be defined as an area ranging from the outer sides of the display area DA to the edges of the display panel  100 . In the non-display area NDA, a scan driver  110  (see  FIG.  4   ) for applying scan signals to the scan lines, and link lines for connecting the data lines and the display driving circuit  200  may be disposed. 
     The protruding area PA may protrude from one side of the main area MA. For example, as illustrated in  FIG.  2   , the protruding area PA may protrude from the lower side of the main area MA. The length, in the first direction (or the X-axis direction), of the protruding area PA may be smaller than the length, in the first direction (or the X-axis direction), of the main area MA. 
     The protruding area PA may include a bending area BA and a pad area PDA. The pad area PDA may be disposed on one side of the bending area BA, and the main area MA may be disposed on the other side of the bending area BA. For example, the pad area PDA may be disposed on the lower side of the bending area BA, and the main area MA may be disposed on the upper side of the bending area BA. 
     The display panel  100  may be formed to be flexible, and may thus be bendable, rollable, or foldable. Accordingly, the display panel  100  can be bent in the bending area BA in the opposite direction of a third direction (or the opposite direction of the Z-axis direction). The pad area PDA of the display panel  100  may face upward when the display panel  100  is yet to be bent, and may face upward or downward when the display panel  100  is bent. When the display panel  100  is bent, the pad area PDA may be placed below the main area MA and may overlap with the main area MA. 
     In the pad area PDA of the display panel  100 , pads that are electrically connected to the display driving circuit  200  and the circuit board  300  may be disposed. 
     The display driving circuit  200  may output signals and voltages for driving the display panel  100 . For example, the display driving circuit  200  may provide data voltages to the data lines. Also, the display driving circuit  200  may provide a power voltage to the power line, and may provide scan control signals to the scan driver  110 . The display driving circuit  200  may be formed as an integrated circuit (IC), and may then be mounted on the display panel  100 , particularly, in the pad area PDA, in a chip-on-glass (COG) or chip-on-plastic (COP) manner or through ultrasonic bonding, without being limited thereto. In some exemplary embodiments, the display driving circuit  200  may be mounted on the circuit board  300 . 
     The pads may include display pads that are electrically connected to the display driving circuit  200  and touch pads that are electrically connected to touch lines. 
     The circuit board  300  may be attached to the pads via an anisotropic conductive film. As such, the lead lines of the circuit board  300  can be electrically connected to the pads. The circuit board  300  may be a flexible film, such as a flexible printed circuit board (FPCB), a printed circuit board (PCB), or a chip-on-film (COF). 
     The touch driving circuit  400  may be connected to touch electrodes of a touch sensor layer TSL of the display panel  100 . The touch driving circuit  400  applies driving signals to the touch electrodes of the touch sensor layer TSL and measures the capacitances of the touch electrodes. The driving signals may be signals having multiple driving pulses. The touch driving circuit  400  not only can determine the presence of touch input, but also can calculate the touch coordinates of touch input, based on the capacitances of the touch electrodes. 
     The touch driving circuit  400  may be disposed on the circuit board  300 . The touch driving circuit  400  may be formed as an IC, and may then be mounted on the circuit board  300 . 
       FIG.  3    is a cross-sectional view taken along line I-I′ of  FIG.  2   . 
     Referring to  FIG.  3   , the display panel  100  may include a display unit DU and a touch sensing unit TDU, which is disposed on the display unit DU. The display unit DU may include a substrate SUB, a thin-film transistor (TFT) layer TFTL, a light-emitting element layer EML, and a thin-film encapsulation layer TFEL. 
     The substrate SUB may be formed of an insulating material, such as glass, quartz, or a polymer resin. For example, the substrate SUB may include polyethersulphone (PES), polyacrylate (PA), polyarylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), polyallylate, polyimide (PI), polycarbonate (PC), cellulose triacetate (CAT), cellulose acetate propionate (CAP), or a combination thereof. As another example, the substrate SUB may include metal. 
     The substrate SUB may be a rigid substrate or may be a flexible substrate that is bendable, foldable, or rollable. When the substrate SUB is a flexible substrate, the substrate SUB may include polyimide without being limited thereto. 
     The TFT layer TFTL may be disposed on the substrate SUB. In the TFT layer TFTL, not only the TFTs of the pixels, but also the scan lines, the data lines, the power line, scan control lines, and routing lines connecting the pads and the data lines, may be formed. Each of the TFTs may include a gate electrode, a semiconductor layer, a source electrode, and a drain electrode. When the scan driver  110  is formed in the non-display area NDA of the display panel  100 , as illustrated in  FIG.  4   , the scan driver  110  may include the TFTs. 
     The TFT layer TFTL may be disposed in the display area DA and in the non-display area NDA. Specifically, the TFTs of the pixels, the scan lines, the data lines, and the power line may be disposed in the display area DA. The scan control lines and the link lines may be disposed in the non-display area NDA. 
     The light-emitting element EML may be disposed on the TFT layer TFTL. The light-emitting element layer EML may include the pixels, each having a first electrode, a light-emitting layer, and a second electrode, and a pixel-defining film defining the pixels. The light-emitting layer may include an organic material. In this case, the light-emitting layer may include a hole transport layer, an organic light-emitting layer, and an electron transport layer. In response to a predetermined voltage applied to the first electrode and a cathode voltage applied to the second electrode, holes and electrons may move to the organic light-emitting layer through the hole transport layer and the electron transport layer, and may be combined together to emit light. The pixels of the light-emitting layer EML may be disposed in the display area DA. 
     The thin-film encapsulation layer TFEL may be disposed on the light-emitting element layer EML. The thin-film encapsulation layer TFEL prevents oxygen or moisture from infiltrating into the light-emitting element layer EML. To this end, the thin-film encapsulation layer TFEL may include at least one inorganic film. The inorganic film may be a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer, without being limited thereto. Also, the thin-film encapsulation layer TFEL protects the light-emitting element layer EML against foreign materials, such as dusts. To this end, the thin-film encapsulation layer TFEL may include at least one organic film. The organic film may include an acrylic resin, an epoxy resin, a phenolic resin, a polyamide (PA) resin, or a PI resin, without being limited thereto. 
     The thin-film encapsulation layer TFEL may be disposed in both the display area DA and the non-display area NDA. Specifically, the thin-film encapsulation layer TFEL may be disposed to cover the light-emitting element layer EML in both the display area DA and the non-display area NDA, and to cover the TFT layer TFTL in the non-display area NDA. 
     The touch sensing unit TDU may be disposed on the thin-film encapsulation layer TFEL. Since the touch sensing unit TDU according to an exemplary embodiment can be disposed directly on the thin-film encapsulation layer TFEL, the thickness of the display device  10  can be reduced as compared to a case where an additional touch panel including the touch sensor layer TSL is attached to the thin-film encapsulation layer TFEL. 
     The touch sensing unit TDU may include touch electrodes for detecting touch input from a user in a capacitive manner, and touch lines connecting the touch electrodes. For example, the touch sensing unit TDU may detect touch input from the user in a self-capacitance manner or in a mutual capacitance manner. 
     The touch electrodes of the touch sensing unit TDU may be disposed in a touch sensor area TSA, as illustrated in  FIG.  5   . The touch lines of the touch sensing unit TDU may be disposed in a touch peripheral area TPA which overlaps with the non-display area NDA, as illustrated in  FIG.  5   . 
     According to an exemplary embodiment, a passivation layer may be disposed on the touch sensing unit TDU. The passivation layer may include, for example, a window member. The passivation layer may be attached on the touch sensing unit TDU via an optically clear adhesive (OCA). In some exemplary embodiments, the display device  10  may further include an optical member. For example, an optical member, such as a polarizing film, may be interposed between the touch sensing unit TDU and the passivation layer. 
       FIG.  4    is a layout view of the display unit of  FIG.  3   . 
       FIG.  4    exemplarily illustrates only pixels P, scan lines SL, data lines DL, a power line PL, scan control lines SCL, the scan driver  110 , the display driving circuit  200 , and display pads DP. 
     Referring to  FIG.  4   , the display unit DU may include the display area DA and the non-display area NDA. The display area DA may include first and second display short sides DSS 1  and DSS 2  which extend in the first direction (or the X-axis direction) and are opposite to each other in the second direction (or the Y-axis direction), and first and second display long sides DLS 1  and DLS 2  which extend in the second direction (or the Y-axis direction) and are opposite to each other in the first direction (or the X-axis direction). The corners at which the first and second display long sides DLS 1  and DLS 2  and the first and second display short sides DSS 1  and DSS 2  meet may be rounded to have a predetermined curvature, but the inventive concepts are not limited thereto. For example, in some exemplary embodiments, the corners at which the first and second display long sides DLS 1  and DLS 2  and the first and second display short sides DSS 1  and DSS 2  meet may be cut off. 
     The scan lines SL, the data lines DL, the power line PL, and the pixels P are disposed in the display area DA. The scan lines SL may be formed to be substantially parallel to one another in the first direction (or the X-axis direction), and the data lines DL may be formed to be substantially parallel to one another in the second direction (or the Y-axis direction), which intersects the first direction (or the X-axis direction). The power line PL may include at least one line extending substantially in parallel to the data lines DL in the second direction (or the Y-axis direction) and a plurality of lines branched off from the at least one line in the first direction (or the X-axis direction). 
     Each of the pixels P may be connected to one of the scan lines SL, one of the data lines DL, and the power line PL. Each of the pixels P may include TFTs, an OLED, and a capacitor, and the TFTs may include a driving transistor and at least one switching transistor. In response to a scan signal applied from the scan lines SL, the pixels P may receive data voltages from the data lines DL, and may emit light by applying driving currents to the OLEDs thereof in accordance with the data voltages applied to the gate electrodes thereof. 
     The scan driver  110  may be connected to the display driving circuit  200  via at least one scan control line SCL. Accordingly, the scan driver  110  can receive scan control signals from the display driving circuit  200 . The scan driver  110  may generate scan signals in accordance with the scan control signals, and may provide the scan signals to the scan lines SL. 
       FIG.  4    illustrates that the scan driver  110  is disposed in a part of the non-display area NDA on the left side the display area DA, but the inventive concepts are not limited thereto. For example, in some exemplary embodiments, the scan driver  110  may be disposed not only in the part of the non-display area NDA on the left side the display area DA, but also in a part of the non-display area NDA on the right side of the display area DA. 
     The display driving circuit  200  is connected to the display pads DP, which are disposed in the pad area PDA, and receives digital video data and timing signals. The display driving circuit  200  converts the digital video data into positive/negative analog data voltages, and provides the positive/negative analog data voltages to the data lines DL via the link lines LL. Also, the display driving circuit  200  generates scan control signals for controlling the scan driver  110 , and provides the scan control signals via the scan control lines SCL. Pixels P to which data voltages are to be provided are selected by scan signals from the scan driver  110 , and data voltages are provided to the selected pixels P. The display driving circuit  200  may be formed as an IC, and may be attached to the substrate SUB in a COG or COP manner or through ultrasonic bonding. 
       FIG.  5    is a layout view of a touch sensing unit according to an exemplary embodiment.  FIG.  5    exemplarily illustrates only first and second touch electrodes TE and RE (see  FIG.  19   ), first touch lines TL 1  through TL 16 , second touch lines RL 1  through RL 33 , first touch pad portions TP 1 , and second touch pad portions TP 2 . The first touch lines TL 1  through TL 16  will hereinafter be referred to as the first through sixteenth driving lines TL 1  through TL 16 , respectively, and the second touch lines RL 1  through RL 33  will hereinafter be referred to as the first through thirty-third sensing lines RL 1  through RL 33 , respectively. 
     Referring to  FIG.  5   , the touch sensing unit TDU includes the touch sensor area TSA, through which touch input from the user may be detected, and the touch peripheral area TPA disposed on the periphery of the touch sensor area TSA. The touch sensor area TSA may overlap with the display area DA of the display unit DU, and the touch peripheral area TPA may overlap with the non-display area NDA of the display unit DU. 
     The touch sensor area TSA may include first and second short sides SS 1  and SS 2  which extend in the first direction (or the X-axis direction) and are opposite to each other in the second direction (or the Y-axis direction), and first and second long sides LS 1  and LS 2  which extend in the second direction (or the Y-axis direction) and are opposite to each other in the first direction (or the X-axis direction). The corners at which the first and second short sides SS 1  and SS 2  and the first and second long sides LS 1  and LS 2  meet may be rounded to have a predetermined curvature, without being limited thereto. For example, in some exemplary embodiment embodiments, the corners at which the first and second short sides SS 1  and SS 2  and the first and second long sides LS 1  and LS 2  meet may be cut off. 
     The first short side SS 1  and the first display short side DSS 1  may overlap with each other, and may have substantially the same length. The second short side SS 2  and the second display short side DSS 2  may overlap with each other and may have substantially the same length. The first long side LS 1  and the first display long side LSS 1  may overlap with each other and may have substantially the same length, and the second long side LS 2  and the second display long side LSS 2  may overlap with each other and may have substantially the same length. However, the inventive concepts are not limited thereto. In some exemplary embodiments, the first and second short sides SS 1  and SS 2  and the first and second long sides LS 1  and LS 2  of the touch sensor area TSA may have different lengths from the first and second display short sides DSS 1  and DSS 2  and the first and second display long sides LSS 1  and LSS 2  of the display area DA, respectively, and the touch sensor area TSA may have a different shape from the display area DA. 
     In the touch sensor area TSA, touch electrodes (TE and RE) may be disposed. The touch electrodes (TE and RE) may include the first touch electrodes TE and the second touch electrodes RE. The first touch electrodes TE and the second touch electrodes RE may be driving electrodes and sensing electrodes, respectively, or vice versa. The first touch electrodes TE and the second touch electrodes RE will hereinafter be described as being driving electrodes and sensing electrodes, respectively. 
     In the touch sensor area TSA,  16  first touch electrodes TE may be arranged along the first direction (or the X-axis direction), and 33 second touch electrodes RE may be arranged along the second direction (or the Y-axis direction). More particularly, the touch electrodes (TE and RE) may be arranged in 33 rows (EC 1  through EC 33 ) and 16 columns (ER 1  through ER 16 ), the first touch electrode TE may be arranged in the 16 columns (ER 1  through ER 16 ), and the second touch electrodes RE may be arranged in the 33 rows (EC 1  through EC 33 ). However, the inventive concepts are not limited thereto, and the numbers and the arrangement of first touch electrodes TE and second touch electrodes RE disposed in the touch sensor area TSA may be variously modified. 
     The touch electrodes (TE and RE) may have a rhombic shape, without being limited thereto. In some exemplary embodiments, the touch electrodes (TE and RE) may have various other shapes, such as a triangular, rectangular, pentagonal, circular, or bar shape. The first touch electrodes TE and the second touch electrodes RE are illustrated as having the same shape, but the inventive concepts are not limited thereto. In some exemplary embodiments, the first touch electrodes TE may have a different shape, a different area, and/or a different thickness from the second touch electrodes RE. According to an exemplary embodiment, each of the touch electrodes (TE and RE) may have a mesh structure, in which a plurality of openings are formed. 
     The first touch electrode TE may be electrically connected in the second direction (or the Y-axis direction) via first connecting electrodes BE 1  (see  FIG.  19   ), and the second touch electrode RE may be electrically connected in the first direction (or the X-axis direction), which intersects the second direction (or the Y-axis direction), via second connecting electrodes BE 2  (see  FIG.  19   ). The touch sensing unit TDU, which has a major axis and a minor axis, may have larger sensitivity deviations in the major axis direction than in the minor axis direction, and the touch sensitivity of the entire touch sensing unit TDU may decrease depending on the sensitivity deviations in the major axis direction. Accordingly, the second connecting electrodes BE 2  may connect the second touch electrodes RE, which are arranged in the minor axis direction of the touch sensing unit TDU, in the first direction (or the X-axis direction), to reduce the resistance of the first touch electrodes TE, which are arranged in the major axis direction of the touch sensing unit TDU, to effectively reduce the sensitivity deviations in the first touch electrodes TE. In this manner, the touch sensitivity of the entire touch sensing unit TDU can be improved. 
     In order to prevent the first touch electrodes TE and the second touch electrodes RE from being short-circuited at the intersections therebetween, the first connecting electrodes BE 1  and the second connecting electrodes BE 2  may be disposed in different layers. The lamination structure of the first touch electrodes TE, the second touch electrodes RE, the first connecting electrodes BE 1 , and the second connecting electrodes BE 2  will be described later. 
     The first through sixteenth driving lines TL 1  through TL 16  and the first through thirty-third sensing lines RL 1  through RL 33  may be disposed in the touch peripheral area TPA. The first through sixteenth driving lines TL 1  through TL 16  may be electrically connected to the first touch electrodes TE, and the first through thirty-third sensing lines RL 1  through RL 33  may be electrically connected to the second touch electrodes RE. Specifically, the first touch electrodes TE may be electrically connected in the second direction (or the Y-axis direction). The first through sixteenth driving lines TL 1  through TL 16  may be connected to first touch electrodes TE disposed at one end, in the second direction (or the Y-axis direction), of the touch sensor area TSA. 
     For example, as illustrated in  FIG.  5   , the first through sixteenth driving lines TL 1  through TL 16  may be connected to first touch electrodes TE in one-on-one arrangement, at the lower end of the touch sensor area TSA that correspond to the first through sixteenth columns ER 1  through ER 16 . The first driving line TL 1  may be connected to the closest first touch electrode TE to the second short side SS 2  among the first touch electrodes TE in the first column ER 1 , which is disposed on the far right side of the touch sensor area TSA. The sixteenth driving line TL 16  may be connected to the closest first touch electrode TE to the second short side SS 2  among the first touch electrodes TE in the sixteenth column ER 16 , which is disposed on the far left side of the touch sensor area TSA. Referring to  FIG.  5   , the first column ER 1  is the far right column in the touch sensor area TSA, the sixteenth column ER 16  is the far left column in the touch sensor area TSA, and the second through fifteenth columns ER 2  through ER 15  are sequentially arranged between the first and sixteenth columns ER 1  and ER 16 . 
     The second touch electrodes RE are electrically connected in the first direction (or the X-axis direction). The first through thirty-third sensing lines RL 1  through RL 33  are electrically connected to second touch electrodes RE disposed on one or the other side of the touch sensor area TSA. The first through thirty-third sensing lines RL 1  through RL 33  may be divided between the left and right sides of the touch sensor area TSA. 
     For example, as illustrated in  FIG.  5   , the first through twentieth sensing lines RL 1  through RL 20  may be disposed on the left side of the touch sensor area TSA. The first through twentieth sensing lines RL 1  through RL 20  may be connected in one-on-one arrangement to second touch electrodes RE on the left side of the touch sensor area TSA that correspond to the first through twentieth rows EC 1  through EC 20 . The first sensing line RL 1  may be connected to the closest second touch electrode RE to the first long side LS 2  among the second touch electrodes RE in the first row EC 1 , which is the lowermost column in the touch sensor area TSA. The twentieth sensing line RL 20  may be connected to the closest second touch electrode RE to the first long side LS 1  among the second touch electrodes RE in the twentieth row EC 20 . Referring to  FIG.  5   , the first row EC 1  is the lowermost row in the touch sensor area TSA, and the second through twentieth rows EC 2  through EC 20  are sequentially arranged next to the first row EC 1  along the second direction (or the Y-axis direction). 
     The twenty-first through thirty-third sensing lines RL 21  through RL 33  may be disposed on the right side of the touch sensor area TSA. The twenty-first through thirty-third sensing lines RL 21  through RL 33  may be connected in one-on-one arrangement to second touch electrodes RE on the right side of the touch sensor area TSA that correspond to the twenty-first through thirty-third rows EC 21  through EC 33 . The twenty-first sensing line RL 21  may be connected to the closest second touch electrode RE to the second long side LS 2  among the second touch electrodes RE in the twenty-first row EC 21 . The thirty-third sensing line RL 33  may be connected to the closest second touch electrode RE to the second long side LS 2  among the second touch electrodes RE in the thirty-third row EC 33 . Referring to  FIG.  5   , the twenty-second through thirty-second rows EC 22  through EC 32  are sequentially arranged next to the twenty-second row EC 21  along the second direction (or the Y-axis direction). 
     The first through twentieth sensing lines RL 1  through RL 20  may be defined as a first sensing line group or a first second-touch line group, and the twenty-first through thirty-third sensing lines RL 21  through RL 33  may be defined as a second sensing line group or a second second-touch line group. In this case, the sensing lines included in the first sensing line group may be disposed on the left side of the touch sensor area TSA, and the sensing lines included in the second sensing line group may be disposed on the right side of the touch sensor area TSA. In this manner, sensitivity deviations can be more effectively reduced than a configuration where sensing lines are alternately arranged in odd- and even-numbered rows, thereby improving the touch sensitivity of the touch sensing unit TDU. 
     The first sensing line group may include 20 sensing lines, and the second sensing line group may include 13 sensing lines. That is, the number of sensing lines included in the first sensing line group may be different from the number of sensing lines included in the second sensing line group. Since the sensing lines included in the second sensing line group are longer than the sensing lines included in the first sensing line group, any resistance deviations between the first sensing line group and the second sensing line group can be minimized by forming the sensing lines included in the second sensing line group to be wider than the sensing lines included in the first sensing line group. 
     A first guard line GL 1  may be disposed between a first ground line GRL 1  and the twentieth sensing line RL 20  to surround part of the lower side of the touch sensor area TSA, the left side of the touch sensor area TSA, and part of the upper side of the touch sensor area TSA. A second guard line GL 2  may be disposed between a second ground line GRL 2  and the thirty-third sensing line RL 33  to surround part of the lower side of the touch sensor area TSA, the right side of the touch sensor area TSA, and part of the upper side of the touch sensor area TSA. The ends of the first and second guard lines GL 1  and GL 2  may face each other on the upper side of the touch sensor area TSA, and may be spaced apart from each other in the first direction (or the X-axis direction). 
     A third guard line GL 3  may be disposed between a third ground line GRL 3  and the ninth driving line TL 9  to face part of the lower side of the touch sensor area TSA. A fourth guard line GL 4  may be disposed between a fourth ground line GRL 4  and the eighth driving line TL 8  to face part of the lower side of the touch sensor area TSA. A fifth guard line GL 5  may be disposed between the first sensing line RL 1  and the sixteenth driving line TL 16 , and a sixth guard line GL 6  may be disposed between the twenty-first sensing line RL 21  and the first driving line TL 1 . 
     The first ground line GRL 1  may be disposed on the left side of the first guard line GL 1  to surround the first guard line GL 1 . The second ground line GRL 2  may be disposed on the right side of the second guard line GL 2  to surround the second guard line GL 2 . The third ground line GRL 3  may be connected to the far right first touch pad portion TP 1 . The fourth ground line GRL 4  may be connected to the far left second touch pad portion TP 2 . 
     The first and second ground lines GRL 1  and GRL 2  may be disposed along the outermost part of the touch sensing unit TDU on the left side, the upper side, and the right side of the touch sensing unit TDU. The third and fourth ground lines GRL 3  and GRL 4  may be disposed on the lower side of the touch sensing unit TDU. Accordingly, the touch sensor area TSA, the first through sixteenth driving lines TL 1  through TL 16 , and the first through thirty-third sensing lines RL 1  through RL 33  may be surrounded by the first, second, third, and fourth ground lines GRL 1 , GRL 2 , GRL 3 , and GRL 4 . In this manner, any static electricity applied from the outside can be discharged to the first, second, third, and fourth ground lines GRL 1 , GRL 2 , GRL 3 , and GRL 4 . As such, the touch sensor area TSA, the first through sixteenth driving lines TL 1  through TL 16 , and the first through thirty-third sensing lines RL 1  through RL 33  can be protected from static electricity. 
     The first guard line GL 1  may minimize the influence of voltage variations in the first ground line GRL 1  on the first through twentieth sensing lines RL 1  through RL 20 . The second guard line GL 2  may minimize the influence of voltage variations in the second ground line GRL 2  on the twenty-first through thirty-third sensing lines RL 21  through RL 33 . The third guard line GL 3  may minimize the influence of voltage variations in the third ground line GRL 3  on the ninth through sixteenth driving lines TL 9  through TL 16 . The fourth guard line GL 4  may minimize the influence of voltage variations in the fourth ground line GRL 4  on the first through eighth driving lines TL 1  through TL 8 . The fifth guard line GL 5  may minimize the influence between the first sensing line RL 1  and the sixteenth driving line TL 1 . The sixth guard line GL 6  may minimize the influence between the twenty-first sensing line RL 21  and the first driving line TL 1 . 
     To this end, when the first touch electrodes TE and the second touch electrodes RE are driven in a mutual capacitance manner, a ground voltage may be applied to the first, second, third, fourth, fifth, and sixth guard lines GL 1 , GL 2 , GL 3 , GL 4 , GL 5 , and GL 6 . On the other hand, when the first touch electrodes TE and the second touch electrodes RE are driven in a self-capacitance manner, the same driving signals as those applied to the first through sixteenth driving lines TL 1  through TL 16  and the first through thirty-third sensing lines RL 1  through RL 33  may be applied to the first, second, third, fourth, fifth, and sixth guard lines GL 1 , GL 2 , GL 3 , GL 4 , GL 5 , and GL 6 . 
     The ninth through sixteenth driving lines TL 9  through TL 16 , the first through twentieth sensing lines RL 1  through RL 20 , the first, third, and fifth guard lines GL 1 , GL 3 , and GL 5 , and the first and third ground lines GRL 1  and GRL 3  may be connected to the first touch pad portions TP 1 . The first through eighth driving lines TL 1  through TL 8 , the twenty-first through thirty-third sensing lines RL 21  through RL 33 , the second, fourth, and sixth guard lines GL 2 , GL 4 , and GL 6 , and the second and fourth ground lines GRL 2  and GRL 4  may be connected to the second touch pad portions TP 2 .  FIG.  4    exemplarily shows only the display pads DP, and  FIG.  5    exemplarily shows only the first touch pad portions TP 1  and the second touch pad portions TP 2 . However, the display pads DP, the first touch pad portions TP 1 , and the second touch pad portions TP 2  may all be disposed together at the end of the protruding area PA of the display panel  100 , in which case, the display pads DP may be disposed between the first touch pad portions TP 1  and the second touch pad portions TP 2 . For example, the first touch pad portions TP 1  may be disposed on the left side of the array of the display pads DP, and the second touch pad portions TP 2  may be disposed on the right side of the array of the display pads DP. 
     The ninth through sixteenth driving lines TL 9  through TL 16  may be disposed in the area where the first touch pad portions TP 1  are disposed, and the first through eighth driving lines TL 1  through TL 8  may be disposed in the area where the second touch pad portions TP 2  are disposed. As such, the uniformity of the arrangement of wiring can be improved, as well as providing an area to which the display pads DP are formed. Also, since the first through sixteenth driving lines TL 1  through TL 16  are connected only to the first touch electrodes TE at the lower end of the touch sensor area TSA that correspond to the first through sixteenth columns ER 1  through ER 16 , i.e., the first through sixteenth driving lines TL 1  through TL 16  have a single routing structure, the size of the touch peripheral area TPA can be reduced. 
       FIG.  6    is a plan view illustrating the shapes and the arrangement of light-emitting areas and first touch electrodes in an area A of  FIG.  5   . Although  FIG.  6    shows the shapes and the arrangement the light-emitting areas (EMA 1 , EMA 2 , and EMA 3 ) and the first touch electrodes TE, according to an exemplary embodiment, the shapes and the arrangement of the light-emitting areas (EMA 1 , EMA 2 , and EMA 3 ) and the second touch electrodes RE may be the same as those shown in  FIG.  6   . 
     Referring to  FIG.  6   , the first touch electrodes TE may include a plurality of openings OP. The openings OP may include first openings OP 1 , second openings OP 2 , and third openings OP 3 . The first openings OP 1 , the second openings OP 2 , and the third openings OP 3  may have different sizes. For example, the third openings OP 3  may have a smaller size than the first openings OP 1 , and the second openings OP 2  may be smaller than the third openings OP 3 . However, the inventive concepts are not limited thereto. In some exemplary embodiments, the first openings OP 1 , the second openings OP 2 , and/or the third openings OP 3  may have different sizes. 
     First light-emitting areas EMA 1 , second light-emitting areas EMA 2 , and third light-emitting areas EMA 3  may have different sizes from each other. For example, the third light-emitting areas EMA 3  may have a smaller size than the first light-emitting areas EMA 1 , and the second light-emitting areas EMA 2  may have a smaller size than the third light-emitting areas EMA 3 . The first light-emitting areas EMA 1 , the second light-emitting areas EMA 2 , and the third light-emitting areas EMA 3  may be defined by a pixel-defining film, which will be described later. Here, the light-emitting areas (EMA 1 , EMA 2 , and EMA 3 ) may be defined as areas that release, to the outside of the display unit DU, light generated by light-emitting elements that will be described later with reference to  FIG.  7   . 
     In the display unit DU, the number of first light-emitting areas EMA 1  may be the same as the number of third light-emitting areas EMA 3 . The number of second light-emitting areas EMA 2  may be twice the number of first light-emitting areas EMA 1  and twice the number of third light-emitting areas EMA 3 . Also, the number of second light-emitting areas EMA 2  may be the same as the sum of the number of first light-emitting areas EMA 1  and the number of third light-emitting areas EMA 3 . 
     The first light-emitting areas EMA 1  may emit blue light, the second light-emitting areas EMA 2  may emit green light, and the third light-emitting areas EMA 3  may emit red light. However, the inventive concepts are not limited thereto. In some exemplary embodiments, fourth light-emitting areas may be further provided. In some exemplary embodiments, the first light-emitting areas EMA 1 , the second light-emitting areas EMA 2 , and the third light-emitting areas EMA 3  may emit white light. 
       FIG.  6    illustrates that the light-emitting areas (EMA 1 , EMA 2 , and EMA 3 ) have a rectangular shape with rounded corners, but the inventive concepts are not limited thereto. In some exemplary embodiments, the light-emitting areas (EMA 1 , EMA 2 , and EMA 3 ) may have an octagonal shape, a circular shape, or another polygonal shape. 
     The first openings OP 1 , the second openings OP 2 , and the third openings OP 3  correspond to the first light-emitting areas EMA 1 , the second light-emitting areas EMA 2 , and the third light-emitting areas EMA 3 , respectively. For example, the first openings OP 1  of the first touch electrodes TE may overlap with the first light-emitting areas EMA 1  of the display unit DU in a thickness direction, i.e., in the third direction (or the Z-axis direction), the second openings OP 2  of the first touch electrodes TE may overlap with the second light-emitting areas EMA 2  of the display unit DU in the thickness direction, i.e., in the third direction (or the Z-axis direction), and the third openings OP 3  of the first touch electrodes TE may overlap with the third light-emitting areas EMA 3  of the display unit DU in the thickness direction, i.e., in the third direction (or the Z-axis direction). Since the first openings OP 1 , the second openings OP 2 , and the third openings OP 3  overlap with the first light-emitting areas EMA 1 , the second light-emitting areas EMA 2 , and the third light-emitting areas EMA 3 , respectively, in the third direction (or the Z-axis direction), light output from the display unit DU can effectively pass through the touch sensing unit TDU to be released to the outside of the display device  10 . Accordingly, light loss can be minimized. Also, since the overlapping areas of the first touch electrodes TE and a second electrode  173  of  FIG.  7    can be reduced, the parasitic capacitance between the first touch electrodes TE and the second electrode  173  can be reduced. The second touch electrodes RE according to an exemplary embodiment may be formed in substantially the same manner as the first touch electrodes TE, and thus, detailed descriptions of the second touch electrodes RE will be omitted to avoid redundancy. 
       FIG.  7    is a cross-sectional view taken along line II-IF of  FIG.  6   .  FIG.  7    exemplarily shows a region where a second light-emitting area EMA 2  and a second opening OP 2  are formed, however, regions where a first light-emitting area EMA 1  and a first opening OP 1  are formed and where a third light-emitting area EMA 3  and a third opening OP 3  are formed may have substantially the same structure as shown in  FIG.  7    except different sizes thereof. 
     Referring to  FIGS.  6  and  7   , the TFT layer TFTL is formed on the substrate SUB. The TFT layer TFTL includes TFTs  120 , a gate insulating film  130 , an interlayer insulating film  140 , a passivation film  150 , and a planarization film  160 . 
     A first buffer layer BF 1  may be formed on the substrate SUB. The first buffer layer BF 1  may be formed on the substrate SUB to protect the TFTs  120  and an organic light-emitting layer  172  of the light-emitting element layer EML against moisture that may penetrate through the substrate SUB. The first buffer layer BF 1  may include a plurality of inorganic films that are alternately stacked. For example, the first buffer layer BF 1  may be formed as a multilayer film, in which at least one of a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, and an aluminum oxide layer is alternately stacked. In some exemplary embodiments, the first buffer layer BF 1  may be omitted. 
     The TFTs  120  may be formed on the first buffer layer BF 1 . Each of the TFTs  120  includes an active layer  121 , a gate electrode  122 , a source electrode  123 , and a drain electrode  124 .  FIG.  9    illustrates that the TFTs  120  have a top gate structure, in which the gate electrode  122  is disposed above the active layer  121 , but the inventive concepts are not limited thereto. For example, in some exemplary embodiments, the TFTs  120  may have a bottom gate structure, in which the gate electrode  122  is disposed below the active layer  121  or a double gate structure, in which the gate electrode  122  is disposed both above and below the active layer  121 . 
     The active layer  121  is formed on the first buffer layer BF 1 . The active layer  121  may include polycrystalline silicon, monocrystalline silicon, low-temperature polycrystalline silicon, amorphous silicon, or an oxide semiconductor. For example, the oxide semiconductor may be a binary compound (ABx), a ternary compound (ABxCy), or a quaternary compound (ABxCyDz) including indium (In), zinc (Zn), gallium (Ga), tin (Sb), titanium (Ti), aluminum (Al), hafnium (Hf), zirconium (Zr), or magnesium (Mg). For example, the active layer  121  may include indium tin zinc oxide (ITZO) or indium gallium zinc oxide (IGZO). In some exemplary embodiments, a light-shielding layer for blocking external light incident upon the active layer  121  may be formed between the first buffer layer BF 1  and the active layer  121 . 
     The gate insulating film  130  may be formed on the active layer  121 . The gate insulating film  130  may include an inorganic film, such as, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. 
     The gate electrode  122  and a gate line may be formed on the gate insulating film  130 . The gate electrode  122  and the gate line may be formed as single- or multilayer films using molybdenum (Mo), Al, chromium (Cr), gold (Au), Ti, nickel (Ni), neodymium (Nd), copper (Cu), or an alloy thereof. 
     The interlayer insulating film  140  may be formed on the gate electrode  122  and the gate line. The interlayer insulating film  140  may include an inorganic film, such as, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. 
     The source electrode  123  and the drain electrode  124  may be formed on the interlayer insulating film  140 . The source electrode  123  and the drain electrode  124  may be connected to the active layer  121  through insulating film contact holes that penetrate the gate insulating film  130  and the interlayer insulating film  140 . The source electrode  123  and the drain electrode  124  may be formed as single- or multilayer films using Mo, Al, Cr, Au, Ti, Ni, Nd, Cu, or an alloy thereof. 
     The passivation film  150  insulating the TFTs  120  may be formed on the source electrode  123  and the drain electrode  124 . The passivation film  150  may include an inorganic film, such as, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. 
     The planarization film  160 , which planarizes height differences generated by the TFTs  120 , may be formed on the passivation film  150 . The planarization film  160  may include an organic film using an acrylic resin, an epoxy resin, a phenolic resin, a PA resin, or a PI resin. 
     The light-emitting element layer EML is formed on the TFT layer TFTL. The light-emitting element layer EML includes light-emitting elements  170  and a pixel-defining film  180 . 
     The light-emitting elements  170  and the pixel-defining film  180  are formed on the planarization film  160 . Each of the light-emitting elements  170  may include a first electrode  171 , the organic light-emitting layer  172 , and the second electrode  173 . 
     The first electrode  171  may be formed on the planarization film  160 . The first electrode  171  may be connected to the source electrode  123  of each of the TFTs  120  through a contact hole that penetrates the passivation film  150  and the planarization film  160 . 
     When the light-emitting element layer EML is formed as a top emission-type light-emitting element layer that emits light in a direction toward the second electrode  173  with respect to the organic light-emitting layer  172 , the first electrode  171  may include metal having high reflectance, such as a stack of Al and Ti (e.g., Ti/Al/Ti), a stack of Al and ITO (e.g., ITO/Al/ITO), a silver (Ag)-palladium (Pd)-copper (Cu) (APC) alloy, or a stack of an APC alloy and ITO (e.g., ITO/APC/ITO). 
     When the light-emitting element layer EML is formed as a bottom emission-type light-emitting element layer that emits light in a direction toward the first electrode  171  with respect to the organic light-emitting layer  172 , the first electrode  171  may be formed of a transparent conductive oxide (TCO) material, such as ITO or IZO, or a semi-transmissive conductive material, such as Mg, Ag, or an alloy thereof. When the first electrode  171  is formed of a semi-transmissive conductive material, emission efficiency can be improved due to micro-cavities. 
     The pixel-defining film  180  may be formed on the planarization film  160  to define the first electrode  171 , and thus, defining subpixels (RP, GP, and BP). For example, the pixel-defining film  180  may be formed to cover the edges of the first electrode  171 . The pixel-defining film  180  may be formed as an organic film using an acrylic resin, an epoxy resin, a phenolic resin, a PA resin, or a PI resin. 
     Each of the second light-emitting areas EMA 2  may refer to a region in which the first electrode  171 , the organic light-emitting layer  172 , and the second electrode  173  are sequentially stacked, and holes from the first electrode  171  and electrons from the second electrode  173  are combined together in the organic light-emitting layer  172  to emit light. The light-emitting areas (EMA 1 , EMA 2 , and EMA 3 ) may include the light-emitting elements  170 . 
     The organic light-emitting layer  172  is formed on the first electrode  171  and on the pixel-defining film  180 . The organic light-emitting layer  172  may include an organic material and may emit light of a predetermined color. For example, the organic light-emitting layer  172  may include a hole transport layer, an organic material layer, and an electron transport layer. 
     The second electrode  173  is formed on the organic light-emitting layer  172 . The second electrode  173  may be formed to cover the organic light-emitting layer  172 . The second electrode  173  may be a common layer formed in common for all the light-emitting areas (EMA 1 , EMA 2 , and EMA 3 ). In some exemplary embodiments, a capping layer may be formed on the second electrode  173 . 
     In a top emission structure, the second electrode  173  may be formed of a TCO material, such as ITO or IZO, or a semi-transmissive conductive material, such as Mg, Ag, or an alloy thereof. When the second electrode  173  is formed of a semi-transmissive conductive material, emission efficiency can be improved due to micro-cavities. 
     In a bottom emission structure, the second electrode  173  may include metal having high reflectance, such as a stack of Al and Ti (e.g., Ti/Al/Ti), a stack of Al and ITO (e.g., ITO/Al/ITO), an APC alloy, or a stack of an APC alloy and ITO (e.g., ITO/APC/ITO). 
     The thin-film encapsulation layer TFEL is formed on the light-emitting element layer EML. The thin-film encapsulation layer TFEL includes an encapsulation film  190 . 
     The encapsulation film  190  is disposed on the second electrode  173 . The encapsulation film  190  may include at least one inorganic film to prevent oxygen or moisture from infiltrating into the organic light-emitting layer  172  and the second electrode  173 . Also, the encapsulation film  190  may include at least one organic film to protect the light-emitting element layer EML against foreign materials, such as dusts. For example, the encapsulation film  190  may include a first inorganic film disposed on the second electrode  173 , an organic film disposed on the first inorganic film, and a second inorganic film disposed on the organic film. The first and second inorganic films may be formed as silicon nitride layers, silicon oxynitride layers, silicon oxide layers, titanium oxide layers, or aluminum oxide layers, without being limited thereto. The organic film may be formed of an acrylic resin, an epoxy resin, a phenolic resin, a PA resin, or a polyimide resin, without being limited thereto. 
     A second buffer layer BF 2  is formed on the thin-film encapsulation layer TFEL. The second buffer layer BF 2  may include a plurality of inorganic films that are alternately stacked. For example, the second buffer layer BF 2  may be formed as a multilayer film, in which at least one of a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, and an aluminum oxide layer is alternately stacked. In some exemplary embodiments, the second buffer layer BF 2  may be omitted. 
     The touch sensing unit TDU is disposed on the second buffer layer BF 2 . As illustrated in  FIG.  5   , the touch sensing unit TDU may include the first touch electrodes TE, the second touch electrodes RE, the first connecting electrodes BE 1 , the second connecting electrodes BE 2 , the first through sixteenth driving lines TL 1  through TL 16 , the first through thirty-third sensing lines RL 1  through RL 33 , the first through sixth guard lines GL 1  through GL 6 , and the first through fourth ground lines GRL 1  through GRL 4 .  FIG.  7    exemplarily illustrates only the first touch electrodes TE of the touch sensing unit TDU. 
     First and second insulating layers IL 1  and IL 2  are disposed on the second buffer layer BF 2 . 
     The first insulating layer IL 1  may include an inorganic material. For example, the first insulating layer IL 1  may include a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. 
     The second insulating layer IL 2  may include an organic material. For example, the second insulating layer IL 2  may include at least one of an acrylic resin, a methacrylic resin, polyisoprene, a vinyl resin, an epoxy resin, a urethane resin, a cellulose resin, a siloxane resin, a PI resin, a PA resin, and a perylene resin. 
     The second connecting electrodes BE 2  may be disposed between the first insulating layer IL 1  and the second buffer layer BF 2 . The first touch electrodes TE, the second touch electrodes RE, and the first connecting electrodes BE 1  may be disposed between the first and second insulating layers IL 1  and IL 2 . Also, the first through sixteenth driving lines TL 1  through TL 16 , the first through thirty-third sensing lines RL 1  through RL 33 , the first through sixth guard lines GL 1  through GL 6 , and the first through fourth ground lines GRL 1  through GR 4  may be disposed between the first and second insulating layers IL 1  and IL 2 . The arrangement of the first touch electrodes TE, the second touch electrodes RE, the first connecting electrodes BE 1 , and the second connecting electrodes BE 2  will be described later. 
     According to an exemplary embodiment, the first touch electrodes TE, the second touch electrodes RE, the first connecting electrodes BE 1 , the second connecting electrodes BE 2 , the first through sixteenth driving lines TL 1  through TL 16 , the first through thirty-third sensing lines RL 1  through  8133 , the first through sixth guard lines GL 1  through GL 6 , and the first through fourth ground lines GRL 1  through GR 4  may include a conductive material. For example, the conductive material may include metal or an alloy thereof. The metal may include Au, Ag, Al, Mo, Cr, Ti, Ni, Nd, Cu, or platinum (Pt). According to another exemplary embodiment, the first touch electrodes TE, the second touch electrodes RE, the first connecting electrodes BE 1 , the second connecting electrodes BE 2 , the first through sixteenth driving lines TL 1  through TL 16 , the first through thirty-third sensing lines RL 1  through  8133 , the first through sixth guard lines GL 1  through GL 6 , and the first through fourth ground lines GRL 1  through GR 4  may be formed of a transparent conductive material. The transparent conductive material may be silver nanowire (AgNW), indium tin oxide (ITO), indium zinc oxide (IZO), antimony zinc oxide (AZO), indium tin zinc oxide (ITZO), zinc oxide (ZnO), tin oxide (SnO 2 ), carbon nanotube (CNT), or graphene. 
     In some exemplary embodiments, the first touch electrodes TE, the second touch electrodes RE, the first connecting electrodes BE 1 , the second connecting electrodes BE 2 , the first through sixteenth driving lines TL 1  through TL 16 , the first through thirty-third sensing lines RL 1  through  8133 , the first through sixth guard lines GL 1  through GL 6 , and the first through fourth ground lines GRL 1  through GR 4  may have a single- or multilayer structure. When the first touch electrodes TE, the second touch electrodes RE, the first connecting electrodes BE 1 , the second connecting electrodes BE 2 , the first through sixteenth driving lines TL 1  through TL 16 , the first through thirty-third sensing lines RL 1  through  8133 , the first through sixth guard lines GL 1  through GL 6 , and the first through fourth ground lines GRL 1  through GR 4  have a multilayer structure, the first touch electrodes TE may include multiple metal layers. For example, the first touch electrodes TE may have a triple-layer structure of Ti/Al/Ti. 
       FIG.  8    is an enlarged layout view of an area B of  FIG.  5   ,  FIG.  9    is an exemplary enlarged layout view of an area B_ 1  of  FIG.  8   , and  FIG.  10    is another exemplary enlarged layout view of the area B_ 1  of  FIG.  8   . 
     Referring to  FIG.  8   , the first touch electrodes TE may be spaced apart from one another in the second direction (or the Y-axis direction), and pairs of adjacent first touch electrodes TE in the second direction (or the Y-axis direction) may be electrically connected via the first connecting electrodes BE 1 . The first connecting electrodes BE 1  may be disposed on the same layer as the first touch electrodes TE, and may be formed during the formation of the first touch electrodes TE. In an exemplary embodiment, the first touch electrodes TE and the first connecting electrodes BE 1  may be integrally formed. 
     The second touch electrodes RE may be spaced apart from one another in the first direction (or the X-axis direction), and pairs of adjacent second touch electrodes RE in the first direction (or the X-axis direction) may be electrically connected via the second connecting electrodes BE 2 . The second connecting electrodes BE 2  may be disposed on a different layer from the second touch electrodes RE, and may be in contact with the second touch electrodes TE through contact holes CTH. The second connecting electrodes BE 2  may be bent at least once and have the shape of the symbol “&lt;” or “&gt;” in a plan view, however, the inventive concepts are not limited to a particular planar shape of the second connecting electrodes BE 2 . The second connecting electrodes BE 2  may overlap with the first touch electrodes TE and the second touch electrodes RE in the thickness direction, i.e., the third direction (or the Z-axis direction). The contact holes CTH are disposed in regions where the second connecting electrodes BE 2  and the second touch electrodes RE overlap each other, and the pairs of adjacent second touch electrodes RE in the first direction (or the Z-axis direction) are in contact with the second connecting electrodes BE 2  through the contact holes CTH and are electrically connected via the second connecting electrodes BE 2 . 
     Referring to  FIG.  9   , according to an exemplary embodiment, the second connecting electrodes BE 2  may include first connecting portions BE 2   a , which are bent in the second direction (or the Y-axis direction), and second connecting portions BE 2   b , which are bent in the opposite direction of the second direction (or the opposite direction of the Y-axis direction). The first connecting portions BE 2   a  and the second connecting portions BE 2   b  are electrically connected to the pairs of adjacent second touch electrodes RE. However, the inventive concepts are not limited thereto. In some exemplary embodiments, the second connecting electrodes RE may include only the first connecting portions BE 2   a  or the second connecting portions BE 2   b , or may further include additional connecting portions in addition to the first connecting portions BE 2   a  and the second connecting portions BE 2   b.    
     Parts of the first connecting portions BE 2   a , which are bent in the second direction (or the Y-axis direction), may overlap with first touch electrodes TE disposed above the first connecting portions BE 2   a  in the third direction (or the Z-axis direction), and parts of the second connecting portions BE 2   b , which are bent in the opposite direction of the second direction (or the opposite direction of the Y-axis direction), may overlap with first touch electrodes TE disposed below the second connecting portions BE 2   b  in the third direction (or the Z-axis direction). However, the inventive concepts are not limited thereto. In some exemplary embodiments, the first connecting portions BE 2   a  and the second connecting portions BE 2   b  may be formed as bars extending in the first direction (or the X-axis direction), in which case, the first connecting portions BE 2   a  and the second connecting portions BE 2   b  may not overlap with the first touch electrodes TE in the third direction (or the Z-axis direction). In another exemplary embodiment, the first connecting portions BE 2   a  and the second connecting portions BE 2   b  may have different shapes. For example, the first connecting portions BE 2   a  may be bent in the second direction (or the Y-axis direction), and the second connecting portions BE 2   b  may be formed as bars extending in the first direction (or the X-axis direction). In this case, parts of the first connecting portions BE 2   a  may overlap with the first touch electrodes TE disposed above the first connecting portions BE 2   a  in the third direction (or the Z-axis direction), but not with the first touch electrodes TE disposed below the second connecting portions BE 2   b  in the third direction (or the Z-axis direction), and may overlap with the first connecting electrodes BE 1  in the third direction (or the Z-axis direction). 
     Each of the first connecting portions BE 2   a  may include a first connecting line BEL 1 , a second connecting line BEL 2 , and a connecting pattern BEP. Each of the second connecting portions BE 2   b  may also include a first connecting line BEL 1 , a second connecting line BEL 2 , and a connecting pattern BEP. 
     Specifically, each of the first connecting portions BE 2   a  may include first and second connecting lines BEL 1  and BEL 2 , which are bent in the second direction (or the Y-axis direction) at centers thereof. The first and second connecting lines BEL 1  and BEL 2  may be spaced apart from each other in the second direction (or the Y-axis direction), contact holes CTH may be disposed on both sides of each of the first and second connecting lines BEL 1  and BEL 2 , and both ends of each of the first and second connecting lines BEL 1  and BEL 2  may be in contact with different second touch electrodes RE through the contact holes CTH. The connecting pattern BEP may electrically connect the first and second connecting lines BEL 1  and BEL 2 , which are spaced apart from each other. Multiple connecting patterns BEP may be provided. However, the inventive concepts are not limited thereto, and in some exemplary embodiments, the first connecting portions BE 2   a  and the second connecting portions BE 2   b  may be implemented as single connecting lines. 
     Referring to  FIG.  10   , according to another exemplary embodiment, each first connecting portion BE 2   a _ 1  may include a first connecting line BEL 1 , a second connecting line BEL 2 , and a connecting pattern BEP, and each second connecting portion BE 2   b _ 1  may include a first connecting line BEL 1 , a second connecting line BEL 2 , and a connecting pattern BEP. According to the illustrated exemplary embodiment, the second connecting line BEL 2  may further include a disconnected portion CTH, in which case, a pair of adjacent second touch electrodes RE may be connected only via the first connecting line BEL 1 . 
       FIG.  11    is a cross-sectional view taken along line of  FIG.  9   ,  FIG.  12    is a cross-sectional view taken along line IV-IV′ of  FIG.  9   , and  FIG.  13    is a cross-sectional view taken along line V-V′ of  FIG.  9   . The elements of the touch sensing unit TDU have already been described above with reference to  FIGS.  5  through  10   , and thus, the lamination structure of the elements of the touch sensing unit TDU will hereinafter be described with reference to  FIGS.  11  through  13   . 
     Referring to  FIGS.  11  through  13   , the touch sensing unit TDU may include contact areas CTA where the second touch electrodes RE are in contact with the second connecting electrodes BE 2 , first touch electrode areas TEA where the first touch electrodes TE are disposed, and second touch electrode areas REA where the second touch electrodes RE are disposed. 
     The second connecting electrodes BE 2  may be disposed on the second buffer layer BF 2 , and the first insulating layer IL 1  may be disposed on the second connecting electrodes BE 2 . The first insulating layer IL 1  may include the contact holes CTH, which expose parts of the second connecting electrodes BE 2 . 
     The first touch electrodes TE, the second touch electrodes RE, and the first connecting electrodes BE 1  may be disposed on the first insulating layer IL 1 , and the second touch electrodes RE may be in contact with the second connecting electrodes BE 2  through the contact holes CTH, which are disposed in the first insulating layer IL 1 . 
     The second insulating layer IL 2  may be disposed on the first insulating layer the first touch electrodes TE, the second touch electrodes RE, and the first connecting electrodes BE 1 . 
     The second connecting electrodes BE 2 , which are disposed on the first insulating layer IL 1 , may have a first thickness D1, and the second touch electrodes RE, which are disposed on the second insulating layer IL 2  and are electrically connected to the second connecting electrodes BE through the contact holes CTH, may have a second thickness D2. The first and second thicknesses D1 and D2 may be different from each other. For example, the first thickness D1 may be less than the second thickness D2. More particularly, according to an exemplary embodiment, the first thickness D1 may be in a range of about 500 Å to about 2300 Å, and the second thickness D2 may be in a range of about 2300 Å to about 4000 Å, without being limited thereto. 
     The first touch electrodes TE and the first connecting electrodes BE 1 , which are disposed on the second insulating layer IL 2 , may have a third thickness D3. The third thickness D3 may be greater than the first thickness D1. Alternatively, in some exemplary embodiments, the third thickness D3 may be the same as the second thickness D2. For example, the first touch electrodes TE, the second touch electrodes RE, and the first connecting electrodes BE 1  may be formed by the same process, and thus, the second and third thicknesses D2 and D3 may be substantially the same, but the inventive concepts are not limited thereto. In some exemplary embodiments, the first touch electrodes TE, the second touch electrodes RE, and the first connecting electrodes BE 1  may be formed by different processes, and in this case, the second and third thicknesses D2 and D3 may be different from each other. 
     Since the first insulating layer IL 1  includes an inorganic material, the first insulating layer IL 1  has a height difference in areas where the second connecting electrodes BE 2  are disposed. Thus, if the first touch electrodes TE are disposed on the first insulating layer IL 1  having a height difference, the first touch electrodes TE have stepped areas RIA and overlapping areas OVA, in which the first touch electrodes TE overlap with the second connecting electrodes BE 2  in the thickness direction BE 2 . In this case, short circuits may be caused in weak parts WP, which are defined as regions between the stepped areas RIA and the edges of the second connecting electrode BE 2 , and as a result, defects may occur in the touch sensing unit TDU. According to an exemplary embodiment, by reducing the thickness of the second connecting electrodes BE 2 , i.e., the first thickness D1, as shown in  FIG.  13   , the height difference in the first insulating layer IL 1  can be alleviated, and as a result, the weak parts WP can be reinforced. In this manner, the second connecting electrodes BE 2  and the first touch electrodes TE can be prevented in advance or be suppressed from being short-circuited in the weak parts WP. 
       FIG.  14    is a cross-sectional view of an area C of  FIG.  5   ,  FIG.  15    is a cross-sectional view taken along line VI-VI′ of  FIG.  14   , and  FIG.  16    is a cross-sectional view taken along line VII-VII′ of  FIG.  14   .  FIGS.  14  through  16    exemplarily illustrate the structure of the first through sixteenth driving lines TL 1  through TL 16  and the first through thirty-third sensing lines RL 1  through RL 33 . The structure of the first through sixteenth driving lines TL 1  through TL 16  and the first through thirty-third sensing lines RL 1  through RL 33  will hereinafter be described with reference to the twentieth sensing line RL 20  shown in  FIGS.  14  through  16   . It is noted that the first through sixteenth driving lines TL 1  through TL 16 , the first through nineteenth sensing lines RL 1  through RL 19 , and the twenty-first through thirty-third sensing lines RL 21  through RL 33  may have the same structure as the twentieth sensing line RL 20 . 
     Referring to  FIGS.  14  through  16   , the twentieth sensing line RL 20  may include a 20a-th sensing line RL 20   a  and a 20b-th sensing line RL 20   b.    
     The 20a-th sensing line RL 20   a  may have a fourth thickness D4, which is substantially the same as the first thickness D1, and may be disposed on the second buffer layer BF 2 . The first insulating layer IL 1  may include wire contact holes CTRL, which expose parts of the second connecting electrodes BE 2 . 
     The 20b-th sensing line RL 20   b , which has a fifth thickness D5 that is substantially the same as the second and third thicknesses D2 and D3, may be disposed on the first insulating layer ILL and may be in contact with the 20a-th sensing line RL 20   a  through the wire contact holes CTRL, which are disposed in the first insulating layer IL 1 . The second insulating layer IL 2  may be disposed on the first insulating layer IL 1  and the 20b-th sensing line RL 20   b.    
     The twentieth sensing line RL 20  may include a wire contact area CTHLA, in which the 20a- and 20b-th sensing lines RL 20   a  and RL 20   b  are in contact with each other, and an overlapping area OVA, in which the 20a- and 20b-th sensing lines RL 20   a  and RL 20   b  overlap with each other in the thickness direction, and the wire contact area CTHLA may be included in the overlapping area OVA. 
     According to an exemplary embodiment, each of the 20a- and 20b-th sensing lines RL 20   a  and RL 20   b  may have a mesh structure. Since the twentieth sensing line RL 20  includes the 20a- and 20b-th sensing lines RL 20   a  and RL 20   b , which overlap with each other in the thickness direction with the first insulating layer IL 1  interposed therebetween and are electrically connected via the wire contact holes CTRL, the resistance of the twentieth sensing line RL 20  can be reduced due to the resistances of the 20a- and 20b-th sensing lines RL 20   a  and RL 20   b  being connected in parallel. Accordingly, the touch sensitivity of the touch sensing unit TDU can be improved. 
       FIG.  17    is a layout view of a touch sensing unit according to another exemplary embodiment. The touch sensing unit of  FIG.  17    differs from that shown in  FIG.  5   , in that a touch sensing unit TDU_ 1  according to the illustrated exemplary embodiment has a major axis in the first direction (or the X-axis direction) and a minor axis in the second direction (or the Y-axis direction), and that first touch electrodes TE are connected, through contact holes CTH, to first connecting electrodes BE 1 , which are arranged in the first direction (or the X-axis direction). The touch sensing unit TDU_ 1  of  FIG.  17    will hereinafter be described, focusing mainly on the differences with the touch sensing unit TDU of  FIG.  5   . 
     Referring to  FIG.  17   , a touch sensor area TSA of the touch sensing unit TDU_ 1  may include first and second long sides LS 1  and LS 2  which extend in the first direction (or the X-axis direction) and are opposite to each other in the second direction (or the Y-axis direction), and first and second short sides SS 1  and SS 2  which extend in the second direction (or the Y-axis direction) and are opposite to each other in the first direction (or the X-axis direction). 
     In the touch sensor area TSA,  33  first touch electrodes TE may be arranged in the first direction (or the X-axis direction), and 16 second touch electrodes RE may be arranged in the second direction (or the Y-axis direction). More particularly, touch electrodes (TE and RE) may be arranged in 16 rows (EC 1  through EC 16 ) and 33 columns (ER 1  through ER 33 ), the first touch electrode TE may be arranged in the 33 columns (ER 1  through ER 33 ), and the second touch electrodes RE may be arranged in the 16 rows (EC 1  through EC 16 ). However, the inventive concepts are not limited thereto, and the numbers and the arrangement of first touch electrodes TE and second touch electrodes RE disposed in the touch sensor area TSA may be variously modified. 
     The first touch electrodes TE, the second touch electrodes RE, and second connecting electrodes BE 2  may be disposed on the same layer, and the first connecting electrodes BE 1  may be disposed on a different layer from the first touch electrodes TE, the second touch electrodes RE, and second connecting electrodes BE 2 . For example, the first connecting electrodes BE 1  may be disposed below the first touch electrodes TE, the second touch electrodes RE, and second connecting electrodes BE 2 , while the first touch electrodes TE may be in contact with the first connecting electrodes BE 1  through contact holes. However, the inventive concepts are not limited thereto. For example, in some exemplary embodiments, the first connecting electrodes BE 1  may be disposed above the first touch electrodes TE, the second touch electrodes RE, and second connecting electrodes BE 2 . 
     The first touch electrode TE may be electrically connected in the second direction (or the Y-axis direction) via the first connecting electrodes BE 1 , and the second touch electrode RE may be electrically connected in the first direction (or the X-axis direction), which intersects the second direction (or the Y-axis direction), via the second connecting electrodes BE 2 . The touch sensing unit TDU_ 1 , which has a major axis and a minor axis, may have larger sensitivity deviations in the major axis direction than in the minor axis direction, and the touch sensitivity of the entire touch sensing unit TDU_ 1  may decrease depending on the sensitivity deviations in the major axis direction. Accordingly, the first connecting electrodes BE 1  may connect the first touch electrodes RE 1 , which are arranged in the minor axis direction of the of the touch sensing unit TDU_ 1 , in the first direction (or the X-axis direction) to reduce the resistance of the second touch electrodes RE, which are arranged in the major axis direction of the touch sensing unit TDU_ 1 , to effectively reduce the sensitivity deviations in the second touch electrodes RE. In this manner, the touch sensitivity of the entire touch sensing unit TDU_ 1  can be improved. 
     First through thirty-third driving lines TL 1  through TL 33  and first through sixteenth sensing lines RL 1  through RL 16  may be disposed in a touch peripheral area TPA. The first through thirty-third driving lines TL 1  through TL 33  may be electrically connected to the first touch electrodes TE, and the first through sixteenth sensing lines RL 1  through RL 16  may be electrically connected to the second touch electrodes RE. Specifically, the first touch electrodes TE may be electrically connected in the second direction (or the Y-axis direction). The first through thirty-third driving lines TL 1  through TL 33  may be connected to first touch electrodes TE disposed at one end, in the second direction (or the Y-axis direction), of the touch sensor area TSA. 
     For example, the first through thirty-third driving lines TL 1  through TL 33  may be connected to first touch electrodes TE in one-on-one arrangement at the lower end of the touch sensor area TSA that correspond to the first through thirty-third columns ER 1  through ER 33 . The first driving line TL 1  may be connected to the closest first touch electrode TE to the second long side LS 2  among the first touch electrodes TE in the first column ER 1 , which is disposed on the far right side of the touch sensor area TSA. The thirty-third driving line TL 33  may be connected to the closest first touch electrode TE to the second long side LS 2  among the first touch electrodes TE in the thirty-third column ER 33 , which is disposed on the far left side of the touch sensor area TSA. Referring to  FIG.  17   , the first column ER 1  is the far right column in the touch sensor area TSA, the thirty-third column ER 33  is the far left column in the touch sensor area TSA, and the second through thirty-second columns ER 2  through ER 32  are sequentially arranged between the first and thirty-third columns ER 1  and ER 33 . 
     The second touch electrodes RE are electrically connected in the first direction (or the X-axis direction). The first through sixteenth sensing lines RL 1  through RL 16  are electrically connected to second touch electrodes RE disposed on one or the other side of the touch sensor area TSA. The first through sixteenth sensing lines RL 1  through RL 16  may be divided between the left and right sides of the touch sensor area TSA. 
     For example, as illustrated in  FIG.  17   , the first through tenth sensing lines RL 1  through RL 10  may be disposed on the left side of the touch sensor area TSA. The first through tenth sensing lines RL 1  through RL 10  may be connected to second touch electrodes RE in one-on-one arrangement on the left side of the touch sensor area TSA that correspond to the first through tenth rows EC 1  through EC 10 . The first sensing line RL 1  may be connected to the closest second touch electrode RE to the first short side SS 1  among the second touch electrodes RE in the first row EC 1 , which is the lowest column in the touch sensor area TSA. The tenth sensing line RL 10  may be connected to the closest second touch electrode RE to the first short side SS 1  among the second touch electrodes RE in the tenth row EC 10 . Referring to  FIG.  17   , the first row EC 1  is the lowermost row in the touch sensor area TSA, and the second through tenth rows EC 2  through EC 10  are sequentially arranged next to the first row EC 1  along the second direction (or the Y-axis direction). 
     The eleventh through sixteenth sensing lines RL 11  through RL 16  may be disposed on the right side of the touch sensor area TSA. The eleventh through sixteenth sensing lines RL 11  through RL 16  may be connected to second touch electrodes RE in one-on-one arrangement on the right side of the touch sensor area TSA that correspond to the eleventh through sixteenth rows EC 11  through EC 16 . The eleventh sensing line RL 11  may be connected to the closest second touch electrode RE to the second short side SS 2  among the second touch electrodes RE in the eleventh row EC 11 . The sixteenth sensing line RL 16  may be connected to the closest second touch electrode RE to the second short side SS 2  among the second touch electrodes RE in the sixteenth row EC 16 . Referring to  FIG.  17   , the twelfth through sixteenth rows EC 12  through EC 16  are sequentially arranged next to the eleventh row EC 11  along the second direction (or the Y-axis direction). 
     The first through tenth sensing lines RL 1  through RL 10  may be defined as a first sensing line group or a first second-touch line group, and the eleventh through sixteenth sensing lines RL 11  through RL 16  may be defined as a second sensing line group or a second second-touch line group. In this case, the first sensing line group may be disposed on the left side of the touch sensor area TSA, and the second sensing line group may be disposed on the right side of the touch sensor area TSA. In this manner, sensitivity deviations can more effectively be reduced than a configuration where sensing lines are alternately arranged in odd- and even-numbered rows, thereby improving touch sensitivity. 
     The first sensing line group may include 10 sensing lines, and the second sensing line group may include 6 sensing lines. That is, the number of sensing lines included in the first sensing line group may be different from the number of sensing lines included in the second sensing line group. Since the sensing lines included in the second sensing line group are longer than the sensing lines included in the first sensing line group, any resistance deviations between the first sensing line group and the second sensing line group can be minimized by forming the sensing lines included in the second sensing line group to be wider than the sensing lines included in the first sensing line group. 
     A first guard line GL 1  may be disposed between a first ground line GRL 1  and the tenth sensing line RL 10  to surround part of the lower side of the touch sensor area TSA, the left side of the touch sensor area TSA, and part of the upper side of the touch sensor area TSA. A second guard line GL 2  may be disposed between a second ground line GRL 2  and the sixteenth sensing line RL 16  to surround part of the lower side of the touch sensor area TSA, the right side of the touch sensor area TSA, and part of the upper side of the touch sensor area TSA. The ends of the first and second guard lines GL 1  and GL 2  may face each other on the upper side of the touch sensor area TSA, and may be spaced apart from each other in the first direction (or the X-axis direction). 
     A third guard line GL 3  may be disposed between a third ground line GRL 3  and the seventeenth driving line TL 17  to face part of the lower side of the touch sensor area TSA. A fourth guard line GL 4  may be disposed between a fourth ground line GRL 4  and the sixteenth driving line TL 16  to face part of the lower side of the touch sensor area TSA. A fifth guard line GL 5  may be disposed between the first sensing line RL 1  and the thirty-third driving line TL 33 , and a sixth guard line GL 6  may be disposed between the eleventh sensing line RL 11  and the first driving line TL 1 . 
     The seventeenth through thirty-third driving lines TL 17  through TL 33 , the first through tenth sensing lines RL 1  through RL 10 , the first, third, and fifth guard lines GL 1 , GL 3 , and GL 5 , and the first and third ground lines GRL 1  and GRL 3  may be connected to first touch pad portions TP 1 . The first through sixteenth driving lines TL 1  through TL 16 , the eleventh through sixteenth sensing lines RL 11  through RL 16 , the second, fourth, and sixth guard lines GL 2 , GL 4 , and GL 6 , and the second and fourth ground lines GRL 2  and GRL 4  may be connected to second touch pad portions TP 2 . Since the seventeenth through thirty-third driving lines TL 17  through TL 33  are disposed in an area where the first touch pad portions TP 1  are disposed, and the first through sixteenth driving lines TL 1  through TL 16  are disposed in an area where the second touch pad portions TP 2  are disposed, the uniformity of the arrangement of wiring can be improved, as well as providing an area on which display pads DP can be provided. Also, since the first through thirty-third driving lines TL 1  through TL 33  are connected only to the first touch electrodes TE at the lower end of the touch sensor area TSA that correspond to the first through thirty-third columns ER 1  through ER 33 , i.e., the first through thirty-third driving lines TL 1  through TL 33  have a single routing structure, the size of the touch peripheral area TPA can be reduced. 
       FIG.  18    is a layout view of a touch sensing unit according to another exemplary embodiment,  FIG.  19    is an exemplary enlarged layout view of an area D of  FIG.  18   ,  FIG.  20    is another exemplary enlarged layout view of the area D of  FIG.  18   ,  FIG.  21    is still another exemplary enlarged layout view of the area D of  FIG.  18   ,  FIG.  22    is yet another exemplary enlarged layout view of the area D of  FIG.  18   , and  FIG.  23    is still yet another exemplary enlarged layout view of the area D of  FIG.  18   . The touch sensing units of  FIGS.  18  through  23    are different from the touch sensing unit of  FIG.  5   , in that dummy patterns DMP are formed in touch electrodes (TE and RE). The touch sensing units of  FIGS.  18  through  23    will hereinafter be described, focusing mainly on the differences with the touch sensing unit of  FIG.  5   . 
     Referring to  FIGS.  18  through  23   , a touch sensing unit TDU_ 2  may include the dummy patterns DMP. The dummy patterns DMP may be disposed on the same layer as the touch electrodes (TE and RE), and may include substantially the same material as the touch electrodes (TE and RE), without being limited thereto. For example, in some exemplary embodiments, the dummy patterns DMP may be disposed on a layer above or below the touch electrodes (TE and RE), and may include a different material from the touch electrodes (TE and RE). According to an exemplary embodiment, when the touch electrodes (TE and RE) have a mesh structure, the dummy patterns DMP may also have a mesh structure. 
     Pattern holes PH may be formed in the touch electrodes (TE and RE) to which the dummy patterns DMP may be arranged. For example, the touch electrodes (TE and RE) may have at least their centers opened to expose the layer disposed therebelow. For example, if a first insulating layer IL 1  is disposed below the touch electrodes (TE and RE), part of the first insulating layer IL may be exposed through the pattern holes PH. 
     The pattern holes PH, to which the dummy patterns DMP may be arranged, may have a larger area than the dummy patterns DMP. As such, the dummy patterns DMP in the pattern holes PH may be spaced apart from the touch electrodes (TE and RE). More particularly, the dummy patterns DMP may be arranged in the pattern holes PH in the form of islands and may be floated, but the inventive concepts are not limited thereto. For example, in some exemplary embodiments, a ground voltage may be applied to the dummy patterns DMP. By providing the dummy patterns DMP in the touch electrodes (TE and RE) of the touch sensing unit TDU_ 2 , the parasitic capacitance of the touch electrodes (TE and RE) can be reduced. 
     In some exemplary embodiments, as illustrated in  FIGS.  18  and  19   , the dummy patterns DMP may have a rhombic shape, and may be disposed in the pattern holes PH of first touch electrodes TE. For example, the first touch electrodes TE may be spaced apart from one another in the second direction (or the Y-axis direction), and pairs of adjacent first touch electrodes TE in the second direction (or the Y-axis direction) may be electrically connected via first connecting electrodes BE 1 , and second touch electrodes RE may be spaced apart from one another in the first direction (or the X-axis direction), and pairs of adjacent second touch electrodes RE in the first direction (or the X-axis direction) may be electrically connected via second connecting electrodes BE 2 . The first touch electrodes TE may have rhombic pattern holes PH, and dummy patterns DMP having the same shape as, but a smaller in size than, the pattern holes PH may be disposed in the pattern holes PH. 
     In some exemplary embodiments, as illustrated in  FIG.  20   , each dummy pattern DMP_ 1  may include first and second dummy pattern units DMP 1  and DMP 2 . The first and second dummy pattern units DMP 1  and DMP 2  may have a triangular shape. A pattern hole PH_ 1  including first and second pattern hole units PH 1  and PH 2 , which are spaced apart from each other and have a triangular shape, may be disposed in each first touch electrode TE. The first and second dummy pattern units DMP 1  and DMP 2  may be disposed in the first and second pattern hole units PH 1  and PH 2 , respectively. 
     In some exemplary embodiments, as illustrated in  FIG.  21   , dummy patterns DMP_ 2  may have a rhombic shape and may be disposed in pattern holes PH_ 2  of each first touch electrode TE. For example, a plurality of pattern holes PH 2  may be disposed in each first touch electrode TE, and may be spaced apart from one another, and the dummy patterns DMP_ 2  may be disposed in the plurality of pattern holes PH_ 2 . 
     In some exemplary embodiments, as illustrated in  FIG.  22   , dummy patterns DMP_ 3  may be disposed in pattern holes PH_ 3  of touch electrodes (TE and RE). 
     First touch electrodes TE may include first pattern holes PHa, and second touch electrodes RE may include second pattern holes PHb. The first pattern holes PHa may have a different area from the second pattern holes PHb. For example, the first pattern holes PHa may have a larger area than the second pattern holes PHb. 
     The dummy patterns DMP_ 3  may include first dummy patterns DMPa and second dummy patterns DMPb. For example, the first dummy patterns DMPa may have a larger area than the second dummy patterns DMPb. 
     The first dummy patterns DMPa may be disposed in the first pattern holes PHa of the first touch electrodes TE, and the second dummy patterns DMPb may be disposed in the second pattern holes PHb of the second touch electrodes RE. The first dummy patterns DMPa, which have a relatively large area, may be disposed in the first touch electrodes TE, which have a relatively large parasitic capacitance. 
     In some exemplary embodiments, as illustrated in  FIG.  23   , touch electrodes (TE_ 1  and RE_ 1 ) may have sides that are in zigzags.  FIG.  23    illustrates that each of the sides of each of the touch electrodes (TE_ 1  and RE_ 1 ) is in zigzags, but the inventive concepts are not limited thereto. For example, in another exemplary embodiment, at least one side of each first touch electrodes TE 1  and/or at least one side of each second touch electrode RE_ 1  may be in zigzags. When the sides of each of the touch electrodes (TE_ 1  and RE_ 1 ) are in zigzags, moiré can be prevented from being visible to a user, and as a result, any display defects that may be caused by moiré interference can be suppressed. 
     Although certain exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concepts are not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements as would be apparent to a person of ordinary skill in the art.