Touch sensor, window stack structure including the same, and image display apparatus

Abstract

A touch sensor includes: a substrate layer; first sensing electrodes arranged in a row direction on the substrate layer, each of the first sensing electrodes including a protrusion at both ends; a second sensing electrode arranged in a column direction on the substrate layer, the second sensing electrode including a connection portion at both ends, the second sensing electrode being integrally connected to the connection portion in the column direction; and a bridging electrode electrically connected to adjacent protrusions in the row direction. The protrusions are spaced apart with respect to the connection portions to face each other, and the connection portions include recesses. A window stack structure including the touch sensor and an image display device are also provided.

Description

Technical Field

[0001] This invention relates to touch sensors, window stacking structures including the same, and image display devices. More specifically, this invention relates to touch sensors comprising multiple conductive layers, and window stacking structures and image display devices including the same. Background Technology

[0002] With the development of information technology, there is an increasing demand for display devices with thinner dimensions, lighter weight, and higher power efficiency. These display devices can include flat panel display devices, such as liquid crystal display (LCD) devices, plasma display panel (PDP) devices, electroluminescent display devices, organic light-emitting diode (OLED) display devices, etc.

[0003] Touch panels or touch sensors have also been developed that allow users to input instructions by selecting commands displayed on the screen using their fingers or input tools. These touch panels or touch sensors can be integrated with display devices to enable both display and information input functions within a single electronic device.

[0004] A touch sensor includes sensing electrodes that convert touch input from a user into an electrical signal through changes in capacitance. Since the sensing electrodes are positioned within the display area of ​​an image display device, the image quality displayed from the image display device may degrade when the user identifies the sensing electrodes.

[0005] For example, as disclosed in Korean Patent Application Publication No. 2014-0092366, various image display devices incorporating touchscreen panels including touch sensors have recently been developed. However, there is a need for a structure for the sensing electrodes that prevents identification of the sensing electrodes without reducing electrical performance and the sensitivity of the touch sensor. Summary of the Invention

[0006] According to one aspect of the present invention, a touch sensor with improved optical and electrical properties is provided.

[0007] According to one aspect of the present invention, an image display device is provided that includes a touch sensor having improved optical and electrical properties.

[0008] According to one aspect of the present invention, a window stack structure including a touch sensor having improved optical and electrical properties is provided.

[0009] The above aspects of the present invention will be achieved through the following features or constructions:

[0010] (1) A touch sensor, comprising: a substrate layer; first sensing electrodes arranged in a row direction on the substrate layer, each of the first sensing electrodes including a protrusion at both ends thereof; second sensing electrodes arranged in a column direction on the substrate layer, each of the second sensing electrodes including a connection portion at both ends thereof, the second sensing electrodes being integrally connected to the connection portion in the column direction; and a bridging electrode electrically connected to an adjacent protrusion in the row direction, wherein the protrusions are spaced apart from the connection portion to face each other, and the connection portion includes a recess.

[0011] (2) The touch sensor according to (1) above, wherein the protrusion is inserted into the recess.

[0012] (3) The touch sensor according to (2) above, wherein the connection portion includes: a first portion adjacent to both ends of the second sensing electrode; and a second portion having a width reduced relative to the width of the first portion due to the recess.

[0013] (4) The touch sensor according to (3) above, wherein the length of the recess in the column direction is in the range of 70 μm to 200 μm.

[0014] (5) The touch sensor according to (3) above, wherein the width of the second portion is in the range of 50 μm to 150 μm.

[0015] (6) The touch sensor according to (1) above further includes an insulating layer, the insulating layer at least partially covering the first sensing electrode and the second sensing electrode on the substrate layer.

[0016] (7) The touch sensor according to (6) above, wherein the bridging electrode intersects with the recess on the insulating layer.

[0017] (8) The touch sensor according to (7) above, wherein the bridging electrode is formed through the insulating layer to directly contact the protrusion of the first sensing electrode.

[0018] (9) The touch sensor according to (1) above, wherein the protruding corner and the connecting portion have rounded corners.

[0019] (10) The touch sensor according to (1) above, wherein the corners of the bridging electrode have a rounded shape.

[0020] (11) A window stack structure comprising: a window substrate; and a touch sensor according to any one of (1) to (10) above, the touch sensor being on the window substrate.

[0021] (12) The window stacking structure described in (11) above further includes a polarizing layer, which is located between the window substrate and the touch sensor or on the touch sensor.

[0022] (13) An image display device, comprising: a display panel; and a touch sensor according to any one of (1) to (10) above, the touch sensor being on the display panel.

[0023] In a touch sensor according to an exemplary embodiment of the present invention, the pattern shape in the intersection area of, for example, column-direction sensing electrodes and row-direction sensing electrodes can be changed to prevent electrode recognition or visibility at the intersection area due to the overlap of electrode patterns.

[0024] In some implementations, the pattern shape may include rounded corners to further prevent electrode identification. Attached Figure Description

[0025] Figure 1 This is a schematic top view showing an example of the electrode arrangement in a capacitive touch sensor.

[0026] Figure 2 and Figure 3 These are, respectively, a top plan view and a cross-sectional view showing the intersecting region of a touch sensor according to an exemplary embodiment.

[0027] Figure 4 This is a top plan view showing the intersecting areas of a touch sensor according to some exemplary embodiments.

[0028] Figure 5 This is a cross-sectional schematic diagram illustrating a window stacking structure and an image display device according to an exemplary embodiment.

[0029] Figure 6 and Figure 7 This is a coordinate graph showing the results of measuring the channel resistance based on the width of the connection portion.

[0030] Figure 8 This is a coordinate graph showing the results of measuring the channel resistance based on the length of the recess included in the connection portion. Detailed Implementation

[0031] According to an exemplary embodiment of the present invention, a touch sensor is provided, which includes a protrusion and a recess at the intersection region of sensing electrodes, thereby suppressing electrode visibility. Furthermore, an image display device including the touch sensor is provided.

[0032] The invention will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that such embodiments described with reference to the drawings are provided to further understand the spirit of the invention and do not limit the subject matter to be protected as disclosed in the detailed specification and appended claims.

[0033] The terms “row direction” and “column direction” used here are used to specify two directions that intersect each other, rather than to indicate absolute directions.

[0034] Figure 1 This is a schematic top view showing an example of the electrode arrangement in a capacitive touch sensor.

[0035] refer to Figure 1 The touch sensor includes, for example, a first sensing electrode 50 and a second sensing electrode 60 disposed on a substrate layer 100.

[0036] The substrate layer 100 may include a support layer, an insulating interlayer, and a film-type substrate for forming the sensing electrodes 50 and 60. For example, the substrate layer 100 may include a film material commonly used in touch sensors. For example, the substrate layer 100 may include glass, polymers, and / or inorganic insulating materials. Polymers may include, for example, cyclic olefin polymers (COP), polyethylene terephthalate (PET), polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate (PEN), polyphenylene sulfide (PPS), polyallylate, polyimide (PI), cellulose acetate propionate (CAP), polyethersulfone (PES), cellulose triacetate (TAC), polycarbonate (PC), cyclic olefin copolymers (COC), polymethyl methacrylate (PMMA), etc. Inorganic insulating materials may include, for example, silicon oxides, silicon nitrides, silicon oxynitrides, metal oxides, etc.

[0037] In some embodiments, a layer or film component in an image display device employing a touch sensor can also be used as substrate layer 100. For example, an encapsulation layer or passivation layer included in a display panel can be used as substrate layer 100.

[0038] The first sensing electrode 50 and the second sensing electrode 60 can be arranged along two different intersecting directions. For example, the first sensing electrode 50 can be arranged along the row direction (or X direction) of the upper surface of the substrate layer 100. The second sensing electrode 60 can be arranged along the column direction (or Y direction) of the upper surface of the substrate layer 100.

[0039] Adjacent second sensing electrodes 60 in the column direction can be connected to each other via a connecting portion 65. The connecting portion 65 can be integrally connected to the second sensing electrodes 60 and can be substantially configured as a single integral component.

[0040] Multiple second sensing electrodes 60 can be integrally connected to each other via connecting portions 65 to define a row of second sensing electrodes. The multiple rows of second sensing electrodes can be arranged along a row direction.

[0041] Each of the first sensing electrodes 50 may have an independent island pattern shape. Adjacent first sensing electrodes 50 in the row direction may be electrically connected to each other via bridging electrodes 55.

[0042] Therefore, a first sensing electrode row can be defined, comprising a plurality of first sensing electrodes 50 connected to each other via bridging electrodes 55. The plurality of first sensing electrode rows can be arranged along a column direction.

[0043] The first sensing electrode 50 and the second sensing electrode 60, and / or the bridging electrode 55 may include transparent conductive oxides, such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide (IZTO), cadmium tin oxide (CTO), etc., or transparent conductive materials, such as silver nanowires (AgNW), carbon nanotubes (CNT), graphene, metal mesh, conductive polymers, etc.

[0044] In some embodiments, the bridging electrode 55 may include metals such as silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), titanium (Ti), tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), molybdenum (Mo), calcium (Ca), or alloys thereof.

[0045] In some embodiments, the first sensing electrode 50 and the second sensing electrode 60 and / or the bridging electrode 55 may include a stacked structure of a transparent conductive oxide layer and a metal layer.

[0046] In some embodiments, the bridging electrode 55 may be formed comprising a low-resistance metal to reduce the channel resistance through the first sensing electrode row. In some embodiments, the first sensing electrode 50 and the second sensing electrode 60 may comprise a transparent conductive oxide as described above to improve the transmittance of the touch sensor.

[0047] The traces can extend from each of the first row of sensing electrodes and the second column of sensing electrodes. For example, the first trace 70 can extend from each of the first row of sensing electrodes, and the second trace 80 can extend from each of the second column of sensing electrodes.

[0048] The ends of the first trace 70 and the second trace 80 can be collected in a bonding region located at one end of the substrate layer 100. The ends can be bonded to a flexible printed circuit board (FPCB) via, for example, an anisotropic conductive film (ACF). The touch sensor driver IC chip can be electrically connected to the first trace 70 and the second trace 80 via the FPCB.

[0049] The first trace 70 and the second trace 80 may include silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), palladium (Pd), chromium (Cr), titanium (Ti), tungsten (W), niobium (Nb), tantalum (Ta), vanadium (V), iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), zinc (Zn), molybdenum (Mo), calcium (Ca), or alloys thereof (e.g., silver-palladium-copper (APC)). These may be used alone or in combination.

[0050] In the plan view, the bridging electrode 55 and the connecting portion 65 can be... Figure 1 The overlapping and intersecting areas at point C, indicated by the dashed circle, are as follows: (e.g., ...) Figure 3 As shown, the bridging electrode 55 and the connection portion 65 can face each other relative to the insulating layer 120 between them.

[0051] Therefore, for example, the increased interfacial reflection caused by the difference in refractive index between layers, and the possible color perception difference in the intersecting region C, may affect the user's electrode identification.

[0052] Figure 2 and Figure 3 These are, respectively, a top plan view and a cross-sectional view showing the intersecting region of a touch sensor according to an exemplary embodiment. Specifically, Figure 3 Along the thickness direction Figure 2 A cross-sectional view taken from line I-I'.

[0053] refer to Figure 2 and Figure 3 For reference Figure 1 As described, the first sensing electrode 110 may be physically spaced apart from each other relative to the connection portion 135 integrally connected to the second sensing electrode 130. In a plan view, the bridging electrode 115 may overlap and cross the connection portion 135 on the insulating layer 120.

[0054] In an exemplary embodiment, protrusions 112 may be formed at both ends of the first sensing electrode 110 in the row direction. The protrusions 112 of adjacent first sensing electrodes 110 may be spaced apart so that they face each other in the row direction.

[0055] The second sensing electrodes 130 can be integrally connected to each other via connecting portions 135 formed at both ends of the second sensing electrodes 130 in the column direction. In an exemplary embodiment, the connecting portions 135 may include recesses 132 that can be recessed in the row direction.

[0056] like Figure 2 As shown, a pair of recesses 132 facing each other in the row direction can be formed in a connecting portion 135. The connecting portion 135 may include a central portion whose width is reduced by the recesses 132.

[0057] For example, the connection portion 135 may include a first portion 135a and a second portion 135b. The first portion 135a may include both ends of the connection portion 135 directly connected to the second sensing electrode 130. The second portion 135b may include a portion narrowed by the recess 132. In an exemplary embodiment, a pair of first portions 135a may be connected to both ends of the second portion 135b.

[0058] In some embodiments, a protrusion 112 included in the first sensing electrode 110 may be inserted into a recess 132 included in the connection portion 135 of the second sensing electrode 130. A pair of protrusions 112 adjacent in the row direction may face each other with respect to the connection portion 135 or the second portion 135b.

[0059] The insulating layer 120 may at least partially cover the first sensing electrode 110 and the second sensing electrode 130. A bridging electrode 115 may be formed on the insulating layer 120 to electrically connect adjacent first sensing electrodes 110 in the row direction.

[0060] like Figure 3 As shown, the bridging electrode 115 may include a contact portion 115a that can be formed through the insulating layer 120 and can contact the first sensing electrode 110. In an exemplary embodiment, the contact portion 115a included in the bridging electrode 115 can directly contact the top surface of the protrusion 112 of the first sensing electrode 110.

[0061] A passivation layer 140 covering the bridging electrode 115 can be formed on the insulating layer 120. The insulating layer 120 and the passivation layer 140 may include organic insulating materials, such as siloxane resins, acrylic resins, etc., or inorganic insulating materials, such as silicon oxides, silicon nitrides, silicon oxynitrides, etc.

[0062] As mentioned above, in Figure 1 The electrode-occupied area at the intersection region C shown can be reduced by the protrusion 112 of the first sensing electrode 110 and the recess 132 or the second portion 135b of the second sensing electrode 130. Therefore, electrode visibility at the intersection region C can be reduced or avoided.

[0063] Additionally, the length of the bridging electrode 115 can be reduced by using the recess 132 to decrease the distance between the protrusions 112. Therefore, electrode visibility caused by the overlap of electrode layers can be suppressed or reduced.

[0064] The area of ​​the first portion 135a can be relatively increased in the connection portion 135 to prevent the channel resistance in the second sensing electrode array from being excessively increased by the second portion 135b.

[0065] Therefore, the area or size of the overlap of electrodes in the intersection region C can be reduced to suppress electrode visibility while preventing an increase in channel resistance to maintain an appropriate signal transmission rate.

[0066] Refer again Figure 2 The width (b) of the second portion 135b of the connecting portion 135 may be smaller than the width (a) of the first portion 135a of the connecting portion 135. In some embodiments, the width (width along the row direction) (b) of the second portion 135b of the connecting portion 135 may be from about 50 μm to 150 μm. For example, if the width of the second portion 135b is less than about 50 μm, the channel resistance of the second sensing electrode array may increase excessively. If the width of the second portion 135b exceeds about 150 μm, it may be difficult to achieve the above-mentioned effect of preventing electrode visibility, and the effect of reducing channel resistance may be weakened. In one embodiment, the width of the second portion 135b may be from about 50 μm to about 100 μm.

[0067] In some embodiments, the length (length along the column direction) of the recess 132 (c) can be from about 70 μm to about 200 μm. If the length of the recess 132 is less than about 70 μm, the width of the protrusion 112 can also be excessively reduced, thereby increasing the channel resistance of the first sensing electrode row. In addition, it may not be possible to obtain sufficient clearance between the protrusion 112 and the connecting portion 135, thereby causing mutual signal interference.

[0068] If the length of the recess 132 exceeds approximately 200 μm, the length of the second sensing electrode array may be excessively increased, resulting in an increase in channel resistance.

[0069] Preferably, the length of the recess 132 can be from about 100 μm to about 200 μm.

[0070] Figure 4 This is a top plan view showing the intersecting areas of a touch sensor according to some exemplary embodiments.

[0071] refer to Figure 4The corners of the protrusion 113 in the first sensing electrode 110 and the recess 132 formed in the connection portion 137 of the second sensing electrode 120 can have rounded corner shapes. Therefore, the corners of the first portion 137a and the second portion 137b in the connection portion 137 can also have rounded corner shapes.

[0072] The corners of the electrodes are rounded to further prevent electrode recognition or visibility issues caused by sudden changes in pattern contours. Additionally, the rounded contours reduce moiré patterns caused by overlap with electrodes and lines on the display panel where touch sensors are mounted.

[0073] In some implementations, the corners of the bridging electrode 117 may also be rounded, which makes it more effective to prevent electrode identification and moiré phenomena.

[0074] Figure 5 This is a cross-sectional schematic diagram illustrating a window stacking structure and an image display device according to an exemplary embodiment.

[0075] refer to Figure 5 According to the exemplary embodiment described above, the window stack structure 250 may include a window substrate 230, a polarizing layer 210, and a touch sensor 200.

[0076] The window substrate 230 may include, for example, a hard coating. In one embodiment, a light-shielding pattern 235 may be formed on a peripheral portion of the surface of the window substrate 230. The light-shielding pattern 235 may include a color-printed pattern and may have a single-layer or multi-layer structure. The bezel portion or non-display area of ​​the image display device may be defined by the light-shielding pattern 235.

[0077] The polarizing layer 210 may include a coated polarizer or a polarizing plate. The coated polarizer may include a liquid crystal coating, which may include a crosslinkable liquid crystal compound and a dichroic dye. In this case, the polarizing layer 210 may include an alignment layer for providing the alignment of the liquid crystal coating.

[0078] For example, a polarizing plate may include a polyvinyl alcohol polarizer and a protective film attached to at least one surface of the polyvinyl alcohol polarizer.

[0079] The polarizing layer 210 can be directly attached to the surface of the window substrate 230, or it can be attached via the first adhesive layer 220.

[0080] The touch sensor 200 may be included as a film or panel in the window stack structure 250. In one embodiment, the touch sensor 200 may be bonded to the polarizing layer 210 via a second adhesive layer 225.

[0081] like Figure 5As shown, the window substrate 230, polarizing layer 210, and touch sensor 200 can be sequentially positioned from the viewer's side. In this case, the electrode layer of the touch sensor 200 can be arranged below the polarizing layer 210, effectively preventing the viewer from recognizing the electrode pattern. As described above, electrode recognition can be further prevented by the electrode structure at the intersection region C.

[0082] In one embodiment, the touch sensor 200 can be directly transferred to the window substrate 230 or the polarizing layer 210. In another embodiment, the window substrate 230, the touch sensor 200, and the polarizing layer 210 can be sequentially positioned from the observer's side.

[0083] The image display device may include a display panel 360 and a window stacking structure 250 arranged on the display panel 360.

[0084] The display panel 360 may include a pixel electrode 310, a pixel limiting layer 320, a display layer 330, a counter electrode 340, and an encapsulation layer 350 disposed on the panel substrate 300.

[0085] Pixel circuits including thin-film transistors (TFTs) can be formed on the panel substrate 300, and an insulating layer covering the pixel circuits can be formed. Pixel electrodes 310 can be electrically connected to, for example, the drain of a TFT on the insulating layer.

[0086] The pixel defining layer 320 can be formed on the insulating layer, and the pixel electrode 310 can be exposed through the pixel defining layer 320, thereby defining a pixel area. The display layer 330 can be formed on the pixel electrode 310, and the display layer 330 may include, for example, a liquid crystal layer or an organic light-emitting layer.

[0087] A counter electrode 340 may be disposed on the pixel defining layer 320 and the display layer 330. The counter electrode 340 may be used as a common electrode or cathode, for example, in an image display device. An encapsulation layer 350 may be disposed on the counter electrode 340 to protect the display panel 360.

[0088] In some embodiments, the display panel 360 and the window stack structure 250 can be bonded to each other via an adhesive layer 260. For example, the thickness of the adhesive layer 260 can be greater than the thickness of each of the first adhesive layer 220 and the second adhesive layer 225. The viscoelasticity of the adhesive layer 260 can be about 0.2 MPa or less at temperatures ranging from -20°C to 80°C. In this case, noise from the display panel 360 can be blocked, and interface stress during bending can be reduced, thus preventing damage to the window stack structure 250. In one embodiment, the viscoelasticity of the adhesive layer 260 can be in the range of about 0.01 MPa to about 0.15 MPa.

[0089] Preferred embodiments are presented below to describe the invention in more detail. However, the following examples are given only to illustrate the invention, and those skilled in the art will clearly understand that these examples do not limit the appended claims, but rather that various changes and modifications can be made within the scope and spirit of the invention. Such changes and modifications are appropriately included in the appended claims.

[0090] Experiment Example 1: Measure the channel resistance based on the width of the connection part (second part).

[0091] A first sensing electrode and a second sensing electrode are formed on a COP substrate, each unit electrode having a size of 4mm × 4mm. The second sensing electrode is integrally connected via a connecting portion, and a recess is formed such that the connecting portion includes a second portion with a reduced width, such as... Figure 2 As shown in the diagram, the first sensing electrode is formed to include protrusions facing each other relative to the second portion. The sensing electrode is formed of ITO with a sheet resistance of 40 Ω / □.

[0092] An insulating layer is formed covering the first and second sensing electrodes, and a bridging electrode is formed on the insulating layer to connect adjacent first sensing electrodes. Specifically, a contact hole with a size of 30 μm × 30 μm is formed through the insulating layer. A conductive layer filling the contact hole is formed on the insulating layer, and then patterned to form the bridging electrode.

[0093] Measure the channel resistance of the first sensing electrode row and the second sensing electrode column of the touch sensor manufactured as described above.

[0094] Figure 6 and Figure 7 This is a coordinate graph showing the results of measuring the channel resistance based on the width of the connection portion.

[0095] Specifically, Figure 6 The channel resistance variation is shown when the bridging electrode is formed from ITO with a thin-film resistance of 40 μ / □ to a width of 60 μm (including the width (a) of the first portion in the connection portion of the second sensing electrode is fixed at 250 μm and the length (c) of the recess is fixed at 90 μm), depending on the width (b) of the second portion. Figure 7 This shows that, apart from the bridging electrode being formed of a metal sheet with a thin-film resistance of 0.2 Ω / □ and a width of 4 μm, it is also related to... Figure 6 Changes in channel resistance under the same conditions.

[0096] refer to Figure 6 and Figure 7 The channel resistance (x resistance) of the first sensing electrode row remains constant, while the channel resistance (y resistance) of the second sensing electrode row tends to decrease gradually.

[0097] Experiment Example 2: Measuring Channel Resistance Based on the Length of the Concave Part

[0098] Figure 8 It is a coordinate graph showing the results of measuring the channel resistance based on the length of the recess included in the connection portion.

[0099] Specifically, the sensing electrode and the ITO bridging electrode are formed with the same material and dimensions as the sensing electrode and ITO bridging electrode in Experimental Example 1. When the width (a) of the first portion is fixed at 250 μm and the width (b) of the second portion is fixed at 75 μm, the change in channel resistance is measured based on the change in the length (c) of the recess. The width of the protrusion included in the first sensing electrode increases at the same rate as the change in the length of the recess.

[0100] refer to Figure 8 When the length of the recess increases to more than approximately 70 μm, the decrease and increase in the resistance of the first and second sensing electrodes are balanced, thus suppressing the increase in the total resistance. When the length of the recess is more than approximately 100 μm, the total resistance remains approximately constant.

[0101] For reference Figures 6 to 8 As described, the increase in channel resistance is prevented by adjusting the dimensions of the connection portion and the recess, while also preventing the visibility of the electrodes.

Claims

1. A touch sensor, comprising: Substrate layer; First sensing electrodes are arranged in a row direction on the substrate layer, and each of the first sensing electrodes includes protrusions at both ends thereto. The second sensing electrode is arranged along the column direction on the substrate layer, and the second sensing electrode includes connecting portions at both ends thereto, and the second sensing electrode is integrally connected to the connecting portions in the column direction; An insulating layer that at least partially covers the first sensing electrode and the second sensing electrode on the substrate layer; and A bridging electrode is provided on the insulating layer, and the bridging electrode is electrically connected to an adjacent protrusion in the row direction. The protrusions are spaced apart from the connecting portions so that they face each other. The connecting portion includes: The first part is adjacent to both ends of the second sensing electrode; and The second part has a width that is reduced relative to the width of the first part due to the recess, and the width of the first part is completely greater than the width of the second part. The protrusion is inserted into the recess.

2. The touch sensor according to claim 1, wherein, The length of the recess in the column direction is in the range of 70 μm to 200 μm.

3. The touch sensor according to claim 1, wherein, The width of the second part is in the range of 50 μm to 150 μm.

4. The touch sensor according to claim 1, wherein, The bridging electrode intersects with the recess on the insulating layer.

5. The touch sensor according to claim 4, wherein, The bridging electrode is formed through the insulating layer to directly contact the protrusion of the first sensing electrode.

6. The touch sensor according to claim 1, wherein, The protruding corners and the connecting portion have rounded corners.

7. The touch sensor according to claim 1, wherein, The corners of the bridging electrode have a rounded shape.

8. A window stacking structure, comprising: Window substrate; and The touch sensor according to claim 1 is located on the window substrate.

9. The window stacking structure according to claim 8 further includes a polarizing layer, the polarizing layer being between the window substrate and the touch sensor or on the touch sensor.

10. An image display device, comprising: Display panel; and The touch sensor according to claim 1 is located on the display panel.

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