KR102122067B1 - Touch sensor module and display device including the same - Google Patents

Abstract

The touch sensor module of the embodiments of the present invention includes a base layer including an active region, a pad region, and a protrusion extending from the pad region, sensing electrodes disposed on the active region of the base layer, and branching from at least some of the sensing electrodes And a flexible circuit board connected to the extended traces, the pad portions connected to the distal ends of the traces and disposed on the pad region of the base layer, and the pad portions on the pad region and protrusions of the base layer. Through the protrusion, bonding reliability of the flexible circuit board can be improved.

Description

A touch sensor module and a display device including the same {TOUCH SENSOR MODULE AND DISPLAY DEVICE INCLUDING THE SAME}

The present invention relates to a touch sensor module and a display device including the same. More specifically, the present invention relates to a touch sensor module including sensing electrodes and wires, and a display device including the same.

The touch screen panel is an input device that allows a user's command to be input by selecting an instruction displayed on a screen such as an image display device with a human hand or an object. The touch screen panel is disposed on the front face of the image display device to convert a contact position directly contacting a human hand or object into an electrical signal. Accordingly, the instruction content selected at the contact position can be transmitted as an input signal.

The touch screen panel may include a touch sensor substrate and touch sensing electrodes arranged on the touch sensor substrate. In addition, a circuit member such as a flexible printed circuit board (FPCB) may be combined with the touch screen panel to connect the touch sensing electrodes to a driving integrated circuit (IC) chip.

Recently, in the case of an image display device such as a smart phone, an area (for example, a bezel part) in which circuit connection through the FPCB is implemented is reduced as the display area is increased within a limited area. Therefore, circuit connection reliability may not be easily secured in the fine region. In addition, when the FPCB is bonded to the pad of the touch screen panel, mechanical damage such as cracking of the pad may also occur.

For example, as in Korean Patent Publication No. 2014-0092366, a touch screen panel in which a touch sensor is combined with various image display devices has been developed, but it has not provided a sufficient circuit connection reliability implementation method.

Korean Patent Publication No. 2014-0092366

One object of the present invention is to provide a touch sensor module having improved mechanical, electrical, and operational reliability.

One object of the present invention is to provide a window stack having improved mechanical, electrical, and operational reliability.

One object of the present invention is to provide a display device including a touch sensor module having improved mechanical, electrical, and operational reliability.

1. a base layer comprising an active region, a pad region and a protrusion extending from the pad region; Sensing electrodes disposed on the active region of the base layer; Traces branching and extending from at least some of the sensing electrodes; Pad portions connected to the distal portions of the traces and disposed on the pad region of the base layer; And a flexible circuit board electrically connected to the pad portions on the pad region and the protrusion of the base layer.

2. In the above 1, the pad portion is disposed only on the pad area, does not extend to the protrusion, the touch sensor module.

3. In the above 2, further comprising a conductive intermediate structure disposed between the flexible circuit board and the pad portion, the touch sensor module

4. In the above 3, wherein the conductive intermediate structure comprises an anisotropic conductive film, a touch sensor module.

5. In the above 3, wherein the conductive intermediate structure is in contact with the pad portion and the upper surface of the protrusion, the touch sensor module.

6. The touch sensor module according to the above 1, wherein the flexible circuit board is bent under the substrate layer together with the protrusion.

7. In the above 6, only the protrusion of the base layer is bent, the pad area is not bent, the touch sensor module.

8. In the above 1, a plurality of sensing electrode columns and sensing electrode rows are defined by the sensing electrodes, the touch sensor module.

9. The touch sensor module of 8 above, wherein the traces include first traces each electrically connected to the sensing electrode columns, and second traces each electrically connected to the sensing electrode rows.

10. The touch sensor module according to the above 9, wherein the second traces are alternately arranged on both sides in the row direction of the base layer.

11. The touch sensor module according to the above 1, wherein the traces are electrically connected to each of the sensing electrodes.

12. window substrate; And a touch sensor module according to any one of 1 to 11 above.

13. In the above 12, further comprising an optical layer disposed between the window substrate and the touch sensor module, the window stack.

14. The touch sensor module according to any one of 1 to 11 above; A main board electrically connected to the touch sensor module; And a display panel disposed between the touch sensor module and the main board.

15. The image display device according to 14 above, wherein the flexible circuit board of the touch sensor module is bent and electrically connected to the main board.

16. The image display device according to 15 above, wherein the protrusion of the touch sensor module is bent together with the flexible circuit board.

According to embodiments of the present invention, the bonding area bonded to the flexible circuit board (FPCB) of the touch sensor module may include a pad area and a protrusion in which the base layer is partially expanded. Since the area to be bonded to the flexible circuit board is increased by the protrusion, circuit connection reliability may be improved.

In addition, since the stress is distributed in the protruding portion while the flexible circuit board is pressed and bonded on the pad region, it is possible to prevent damages such as cracks and peeling of pads arranged in the pad region.

In some embodiments, a conductive intermediary structure, such as an anisotropic conductive film (ACF), is disposed between the pad and the flexible circuit board, and air bubbles generated when the anisotropic conductive film is compressed through the protrusion may be discharged or removed. .

In some embodiments, the protrusion may be bent with the flexible circuit board, and an electrical connection with the main board of the image display device may be implemented through the protrusion without bending the pad or wiring. have.

1 is a schematic plan view showing a touch sensor module according to example embodiments.
Fig. 2 is a schematic plan view showing a touch sensor module according to example embodiments.
3 is a schematic partial plan view showing an arrangement of bonding regions according to example embodiments.
4 and 5 are schematic partial plan and partial cross-sectional views, respectively, showing bonding regions and connections of flexible circuit boards in accordance with example embodiments.
Fig. 6 is a schematic cross-sectional view showing a connection between a touch sensor module and a main board according to example embodiments.
7 is a schematic cross-sectional view illustrating a window stack and an image display device according to example embodiments.

Embodiments of the present invention are a plurality of sensing electrodes, traces electrically connected to the sensing electrodes, pads connected to the ends of the traces, and ductility electrically connected to the pads on a bonding area including a protrusion Provided is a touch sensor module including a circuit board. In addition, an image display device with improved electrical connection reliability and mechanical stability is provided through the touch sensor-antenna module.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the following drawings attached to the present specification are intended to illustrate preferred embodiments of the present invention, and serve to further understand the technical idea of the present invention together with the contents of the present invention, so the present invention is described in such drawings. It should not be interpreted as being limited to the matter.

In the following drawings, for example, two directions parallel to and intersecting with the upper surface of the base layer 100 are defined as a first direction and a second direction. The first direction and the second direction may intersect perpendicularly to each other. In addition, a direction perpendicular to the upper surface of the base layer 100 is defined as a third direction. The third direction may correspond to the thickness direction of the touch sensor module.

1 is a schematic plan view showing a touch sensor module according to example embodiments.

Referring to FIG. 1, the touch sensor module may include sensing electrodes 110 and 130, traces 117 and 137 and pad parts 150 disposed on the base layer 100.

The base layer 100 is used in a sense to encompass a film-type base material used as a base layer for forming the sensing electrodes 110 and 130 or an object on which the sensing electrodes 110 and 130 are formed.

According to exemplary embodiments, the base layer 100 may include a flexible material capable of folding or folding. For example, the base layer 100 is a cyclic olefin polymer (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 copolymer ( COC), polymethyl methacrylate (PMMA), and the like, and may include a resin material with improved flexible properties.

The sensing electrodes 110 and 130 may include first sensing electrodes 110 and second sensing electrodes 130. For example, the sensing electrodes 110 and 130 may be arranged to be driven in a mutual capacitance method.

The first sensing electrodes 110 may be arranged, for example, along the first direction (eg, Y direction). In some embodiments, the first sensing electrodes 110 may be physically separated into island type unit electrodes, respectively. In this case, the first sensing electrodes 110 neighboring in the first direction may be electrically connected to each other by the bridge electrode 115.

Accordingly, a first sensing electrode row extending in the first direction may be formed by the plurality of first sensing electrodes 110. Further, a plurality of the first sensing electrode rows may be arranged along the second direction.

The second sensing electrodes 130 may be arranged, for example, along a second direction (eg, X direction). Accordingly, a second sensing electrode row extending in the second direction may be formed by the second sensing electrodes 130. Also, a plurality of the rows of the second sensing electrodes may be arranged along the first direction.

In some embodiments, the second sensing electrodes 130 neighboring in the second direction may be physically or electrically connected to each other by a connection unit 135. For example, the connection part 135 is integrally formed at the same level as the second sensing electrodes 130 and may be provided as a substantially single member with the second sensing electrodes 130.

For example, an insulating layer (not shown) that at least partially covers the connection portion 135 is formed, and a bridge electrode 115 is formed on the insulating layer, so that adjacent first sensing electrodes 110 are second. The sensing electrodes 130 may be electrically connected to each other through the bridge electrode 115 while maintaining insulation.

In some embodiments, the first sensing electrodes 110 are integrally connected along the first direction by a connection unit, and the second sensing electrodes 130 may be electrically connected to each other through a bridge electrode.

The sensing electrodes 110 and 130 and/or the bridge electrode 115 are 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) ), tin (Sn) or alloys thereof (eg, silver-palladium-copper (APC)). These may be used alone or in combination of two or more.

The sensing electrodes 110 and 130 and/or the bridge electrode 115 are, for example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide (IZTO), cadmium It may also include a transparent conductive oxide such as tin oxide (CTO).

In some embodiments, sensing electrodes 110 and 130 and/or bridge electrode 115 may include a stacked structure of transparent conductive oxide and metal. For example, the sensing electrodes 110 and 130 and/or the bridge electrode 115 may have a three-layer structure of a transparent conductive oxide layer-metal layer-transparent conductive oxide layer. In this case, while the flexible properties are improved by the metal layer, the signal transmission speed can be improved by lowering the resistance, and the corrosion resistance and transparency can be improved by the transparent conductive oxide layer.

The active layer A is defined in the center region of the base layer 100, and the sensing electrodes 110 and 130 may be defined on the active region A, for example. The active area A may be a substantial sensing area in which a user's touch is sensed.

The peripheral region of the active region A of the base layer 100 may be provided as a trace region. The trace area may overlap the bezel portion of the image display device. The traces 117 and 137 may include first traces 117 and second traces 137.

For example, the first traces 117 may branch and extend from each of the first sensing electrode rows. The second traces 137 may branch and extend from each of the second sensing electrode rows.

In some embodiments, second traces 137 may be distributedly arranged on both sides of the trace area in the second direction. For example, the second traces 137 may be alternately arranged on both sides along the first direction. Accordingly, an alignment margin of the second traces 137 is secured, and the area of the trace area can be reduced.

The traces 117 and 137 extend toward one end of the base layer 100 and may be aggregated in the bonding region B. Each of the traces 117 and 137 in the bonding area B may be connected to the pad parts 150. In some embodiments, the pad portion 150 may be a terminal portion integrally connected with the distal portions of each trace 117 and 137.

The bonding region B may be provided as a bonding region for electrically connecting the sensing electrodes 110 and 130 and the driving integrated circuit IC through the pad portions 150. According to exemplary embodiments, a circuit connection structure such as a flexible printed circuit board (FPCB) may be bonded to the pad unit 150 in the bonding area B.

Accordingly, physical touch information input to the touch sensor module is converted into an electrical signal due to a difference in capacitance through the first sensing electrode 110 and the second sensing electrode 130, and the electrical signal is pad unit 150 ), for example, it can be transmitted to the driving IC to implement touch sensing.

According to exemplary embodiments, the bonding region B may include a pad region P and a protrusion 105 in which the base layer 100 is partially expanded. For example, the base layer 100 may be defined by protruding or extending in the first direction.

The pad portions 150 are selectively disposed only in the pad region P, and may not extend to the protrusion 105. Accordingly, a substantially total area of the upper surface of the protrusion 105 may be bonded to the flexible circuit board. Therefore, the flexible circuit board can be stably fixed on the bonding region B through the protrusion 105.

In addition, stress applied to the pad portion 150 may be distributed when the flexible circuit board is pressed through the entire area of the upper surface of the protruding portion 105. Therefore, mechanical damage such as cracking and peeling of the pad portion 150 can be effectively suppressed.

Fig. 2 is a schematic plan view showing a touch sensor module according to example embodiments.

Referring to FIG. 2, the sensing electrodes 120 may be provided as independent sensing domains within the active region A of the base layer 100. For example, the sensing electrodes 120 may be arranged to be driven in a self capacitance method.

The traces 125 may branch from each of the sensing electrodes 120 in the active region A and extend, for example, to a trace region allocated to one end of the base layer 100. The traces 125 are collected as a bonding area B among the trace areas, and may be electrically connected to the pad parts 150, respectively.

As described above, the bonding region B may include a pad region P and a protrusion 105 in which the base layer 100 is partially extended in the first direction. The pad portions 150 are selectively arranged in the pad region P, and may not extend to the protrusion 105.

3 is a schematic partial plan view showing an arrangement of bonding regions according to example embodiments.

Referring to FIG. 3, a plurality of bonding regions B may be defined at one end of the base layer 100. Accordingly, a plurality of protrusions 105 may be repeatedly formed at the one end of the base layer 100. For each bonding area B, the pad parts 150 may be connected to the traces 125 and disposed in the pad area P included in the bonding area B.

4 and 5 are schematic partial plan and partial cross-sectional views, respectively, showing bonding regions and connections of flexible circuit boards according to exemplary embodiments. For example, FIG. 5 is a cross-sectional view taken along the line I-I' of FIG. 4 in the third direction.

4 and 5, the flexible circuit board 170 may be electrically connected to the pads 150 on the bonding region B. In some embodiments, the conductive intermediary structure 160 may be disposed between the pad portions 150 and the flexible circuit board 170. The conductive intermediate structure 160 may be provided as a cushioning member for compressing the flexible circuit board 170 on the pad parts 150.

The flexible circuit board 170 may include a core layer (not shown) including a flexible resin and printed circuits disposed on upper and lower surfaces of the core layer. For example, a printed circuit disposed on the lower surface of the core layer may be electrically connected to the pads 150, and a printed circuit disposed on the upper surface of the core layer may be electrically connected to a driving IC. The printed circuits disposed on the upper and lower surfaces may be connected to each other through a via structure penetrating the core layer.

The conductive intermediate structure 160 may include, for example, an anisotropic conductive film (ACF). The anisotropic conductive film may include a resin layer and a conductive filler (eg, conductive balls) dispersed in the resin layer. Electrical connection of the pad parts 150 and the flexible circuit board 170 may be implemented through the conductive filler by compression of the flexible circuit board 170.

According to example embodiments, the bonding area of the conductive intermediate structure 160 and the flexible circuit board 170 may be extended through the protrusion 105 included in the bonding area B.

Therefore, the flexible circuit board 170 is stably fixed to the base layer 100, so that the bonding reliability can be improved. Also, while the conductive intermediary structure 160 covers the pad portion 150, it projects onto the protrusion 105. Since it is expanded, the pad portion 150 can be protected from peeling and damage.

The conductive intermediate structure 160 may directly contact the upper surface of the protrusion 105. Therefore, air bubbles can be suppressed when the conductive intermediate structure 160 is compressed.

Fig. 6 is a schematic cross-sectional view showing a connection between a touch sensor module and a main board according to example embodiments.

Referring to FIG. 6, the touch sensor module may include a conductive layer 140 disposed on the base layer 100 and a flexible circuit board 170 electrically connected to one end of the conductive layer 140. .

The conductive layer 140 may include sensing electrodes 110, 120, 130, traces 117, 125, 137 and pad parts 150, as described with reference to FIGS. 1 and 2. . The flexible circuit board 170 may be electrically connected to the pad parts 150 included in the conductive layer 140 through the conductive intermediate structure 160.

The base layer 100 includes a protrusion 105 formed at one end, and the conductive intermediary structure 160 may be bonded together with the pad parts 150 and the protrusion 105.

The display panel 200 and the main board 250 may be disposed under the touch sensor module. In one embodiment, the display panel 200 may be disposed between the touch sensor module and the main board 250. The configuration of the display panel 200 will be described later in more detail with reference to FIG. 7.

According to exemplary embodiments, the flexible circuit board 170 may be bent in the third direction together with the protrusion 105 to be electrically connected to the main board 250. For example, after the flexible circuit board 170 is bent in the third direction, an end portion thereof extends in the first direction and may be electrically connected to a driving circuit included in the main board 250 through a bonding pad 260. have.

As described above with reference to FIG. 1, the pad portions 150 are disposed only in the pad region P, and may not be disposed on the protrusion 105. Therefore, when the flexible circuit board 170 is bent, only the protrusion 105 is selectively bent, thereby preventing damage due to the bending stress of the pad parts 150 and the traces, and the pad parts 150 are the base layer 100 It can suppress peeling from.

In addition, since the protrusion 105 and the flexible circuit board 170 are bent, the flexible circuit board 170 is stably fixed on the base layer 100 even after bending, so that bonding reliability can be improved.

7 is a schematic cross-sectional view illustrating a window stack and an image display device according to example embodiments.

Referring to FIG. 7, the window stack 350 may include the above-described touch sensor module 300 and the window substrate 330. In FIG. 7, detailed configuration and/or structures of the touch sensor module described with reference to FIGS. 1 to 5 are omitted for convenience of description.

The window substrate 330 includes, for example, a hard coating film, and in one embodiment, a light blocking pattern 335 may be formed on a peripheral portion of one surface of the window substrate 330. The light blocking pattern 335 may include, for example, a color print pattern, and may have a single layer or multi-layer structure. The bezel area or the non-display area of the image display device may be defined by the light blocking pattern 335.

For example, traces and pad portions included in the touch sensor module 300 may be disposed in the bezel area defined by the light blocking pattern 335. Even when the bezel area is reduced according to the expansion of the display area of the image display device, it is possible to maintain or improve the bonding reliability of the flexible circuit board 170 through application of the above-described protrusion 105.

The window stack 350 may further include an optical layer 310. The optical layer 310 may include various optical films or optical structures included in the image display device, and may include a coated polarizer or polarizing plate in some embodiments. The coated polarizer may include a liquid crystal coating layer including a polymerizable liquid crystal compound and a dichroic dye. In this case, the optical layer 310 may further include an alignment layer for imparting alignment to the liquid crystal coating layer.

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

The optical layer 310 may be directly bonded to the one surface of the window substrate 330 or may be attached through the second point adhesive layer 320. In one embodiment, the optical layer 310 may be combined with the touch sensor module 300 through the first point adhesive layer 325.

As illustrated in FIG. 7, the window substrate 330, the optical layer 310, and the touch sensor module 300 may be arranged from the user's viewing side. In this case, since the sensing electrodes of the touch sensor module 300 are disposed under the optical layer 310 including the polarizer or the polarizing plate, the electrode visibility phenomenon can be more effectively prevented.

According to exemplary embodiments, since the flexible circuit board 170 is bonded through the protrusion 105, the flexible circuit board (even if the optical layer 310 including the polarizing plate is previously combined with the touch sensor module 300) 170) It is possible to reduce or prevent damage to the optical layer 310 by the bonding process (for example, burning of a polarizing plate).

The image display device according to example embodiments may include a display panel 460 and a window stack 350 stacked on the display panel 460.

The display panel 460 includes a pixel electrode 410, a pixel defining layer 420, a display layer 430, a counter electrode 440 and an encapsulation layer 450 disposed on the panel substrate 400. Can be.

The panel substrate 400 may include glass or a flexible resin material, and when the flexible resin material is included, the image display device may be provided as a flexible display.

A pixel circuit including a thin film transistor (TFT) is formed on the panel substrate 400, and an insulating film covering the pixel circuit may be formed. The pixel electrode 410 may be electrically connected to the drain electrode of the TFT, for example, on the insulating film.

The pixel defining layer 420 is formed on the insulating layer to expose the pixel electrode 410 to define a pixel area. The display layer 430 is formed on the pixel electrode 410, and the display layer 430 may include, for example, a liquid crystal layer of a liquid crystal display (LCD) device or an organic light emitting layer of an organic light emitting diode (OLED) device. .

The counter electrode 440 may be disposed on the pixel defining layer 420 and the display layer 430. The counter electrode 440 may be provided as, for example, a common electrode or a cathode of the image display device. An encapsulation layer 450 for protecting the display panel 460 may be stacked on the counter electrode 440.

In some embodiments, the display panel 460 and the window stack 350 may be combined through the point adhesive layer 360. For example, the thickness of the point adhesive layer 360 may be greater than the thickness of each of the first and second point adhesive layers 320 and 325, and the viscoelasticity at -20 to 80°C may be about 0.2 MPa or less. In this case, noise from the display panel 460 can be shielded, and interfacial stress can be relaxed during bending to suppress damage to the window stack 350. In one embodiment, the viscoelasticity may be about 0.01 to 0.15MPa.

100: base layer 105: protrusion
110: first sensing electrode 115: bridge electrode
117: first trace 120: sensing electrode
125: trace 130: second sensing electrode
135: connection 137: the second trace
150: pad portion 160: conductive intermediate structure
170: flexible circuit board

Claims (16)

A base layer comprising an active region, a pad region, and a protrusion extending from the pad region;
Sensing electrodes disposed on the active region of the base layer and arranged on the same layer;
Traces branching and extending from at least some of the sensing electrodes;
Pad portions connected to the distal portions of the traces and disposed on the pad region of the base layer; And
And a flexible circuit board electrically connected to the pad parts on the pad region and the protrusion of the substrate layer, wherein the flexible circuit board entirely covers the protrusion on the protrusion, and the flexible circuit board includes the protrusion together with the protrusion. A touch sensor module that is bent under the substrate layer.
The touch sensor module of claim 1, wherein the pad portions are disposed only on the pad area and do not extend to the protrusion.
The touch sensor module of claim 2, further comprising a conductive intermediary structure disposed between the flexible circuit board and the pad portions.
The touch sensor module of claim 3, wherein the conductive intermediate structure includes an anisotropic conductive film.
The touch sensor module according to claim 3, wherein the conductive intermediate structure is in contact with the pad portions and the upper surfaces of the protrusions.
delete The touch sensor module of claim 1, wherein only the protrusion of the base layer is bent, and the pad area is not bent.
The touch sensor module of claim 1, wherein a plurality of sensing electrode columns and sensing electrode rows are defined by the sensing electrodes.
The touch sensor module of claim 8, wherein the traces include first traces each electrically connected to the sensing electrode columns, and second traces each electrically connected to the sensing electrode rows.
The touch sensor module according to claim 9, wherein the second traces are alternately arranged on both sides in a row direction of the base layer.
The touch sensor module of claim 1, wherein the traces are electrically connected to each of the sensing electrodes.
Window substrates; And
A window stack comprising the touch sensor module according to any one of claims 1 to 5 and 7 to 11.
The window stack according to claim 12, further comprising an optical layer disposed between the window substrate and the touch sensor module.
The touch sensor module according to any one of claims 1 to 5 and 7 to 11;
A main board electrically connected to the touch sensor module; And
And a display panel disposed between the touch sensor module and the main board.
The image display device of claim 14, wherein the flexible circuit board of the touch sensor module is bent and electrically connected to the main board.
The image display device of claim 15, wherein the protrusion of the touch sensor module is bent together with the flexible circuit board.

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