Display device with pressure sensor

Abstract

A display device having a pressure sensor is provided. The display device includes: a display panel; and a sensor disposed on one surface of the display panel to detect external pressure. The sensor includes: a first base substrate having a sensing area and a non-sensing area; a plurality of first conductive patterns extending in a first direction in the sensing area of ​​the first base substrate; a second base substrate facing the first base substrate; a plurality of second conductive patterns extending in a second direction intersecting the first conductive patterns disposed on the surface of the first base substrate; a pressure-sensitive material layer disposed between the first conductive patterns and the second conductive patterns, the pressure-sensitive material layer having a resistance that changes in response to pressure; and an adhesive layer connecting the first base substrate and the second base substrate, the adhesive layer and the pressure-sensitive material layer being disposed in the same layer.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2017-0170572, filed on Dec. 12, 2017, which is hereby incorporated by reference for all purposes as if fully set forth herein. Technical Field

[0002] Exemplary embodiments of the invention relate generally to a display device, and more particularly, to a display device having a pressure sensor. Background Art

[0003] As interest in information displays and demand for portable information media increase, research and commercialization have focused on display devices.

[0004] In addition to an image display function, recent display devices include a touch sensor for receiving a user's touch input. Therefore, the user can use the display device more conveniently through the touch sensor.

[0005] Recently, various functions of a display device or an application installed thereon have been provided to a user using pressure due to a touch as well as a touched position.

[0006] The above information disclosed in this Background section is only for understanding the background of the inventive concept and therefore it may contain information that does not constitute the prior art. Summary of the invention

[0007] A display device constructed according to inventive principles and exemplary embodiments includes a pressure sensor that facilitates functions requiring the location and / or intensity of a touch input and can reduce the thickness of the display device, which can contribute to the flexibility of a foldable device.

[0008] According to some embodiments, in a foldable display device constructed according to inventive principles and exemplary embodiments, the durability of a pressure sensor may be improved to reduce or eliminate failures due to bending stress or fatigue.

[0009] 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.

[0010] According to one aspect of the invention, a display device includes: a display panel; and a sensor disposed on one surface of the display panel to detect external pressure. The sensor includes: a first base substrate having a sensing area and a non-sensing area; a plurality of first conductive patterns extending in a first direction in the sensing area of ​​the first base substrate; a second base substrate facing the first base substrate; a plurality of second conductive patterns extending in a second direction intersecting the first conductive patterns disposed on the surface of the first base substrate; a pressure-sensitive material layer disposed between the first conductive patterns and the second conductive patterns, the pressure-sensitive material layer having a resistance that changes in response to pressure; and an adhesive layer connecting the first base substrate and the second base substrate, the adhesive layer and the pressure-sensitive material layer being disposed in the same layer.

[0011] When external pressure is applied to the sensor, the resistance of the pressure-sensitive material layer corresponding to the area where the pressure is applied may decrease.

[0012] The pressure sensitive material layer may include a polymer compound and conductive particles dispersed in the polymer compound.

[0013] The pressure-sensitive material layer may be disposed in the sensing region along an extension direction of the first conductive pattern. The pressure-sensitive material layer may overlap at least some of the plurality of first conductive patterns.

[0014] The adhesive layer may include a first adhesive pattern arranged in the sensing area and a second adhesive pattern arranged in the non-sensing area and contacting the first adhesive pattern, and the second adhesive pattern is connected to the first adhesive pattern. The first adhesive pattern may be arranged between adjacent first conductive patterns in the first conductive pattern or between adjacent second conductive patterns in the second conductive pattern. The first adhesive pattern may be arranged along the extension direction of the first conductive pattern or the second conductive pattern. The second adhesive pattern may be arranged along the edge of the sensing area in the non-sensing area. The width of the first adhesive pattern may be less than the distance between adjacent second conductive patterns. The width of the first adhesive pattern may be equal to the distance between adjacent second conductive patterns.

[0015] The thickness of the adhesive layer may be smaller than a value obtained by adding a thickness of the first conductive pattern and a thickness of the pressure-sensitive material layer. The adhesive layer may include a pressure-sensitive adhesive (PSA).

[0016] Each of the first base substrate and the second base substrate may be flexible and include a foldable flexible region.

[0017] The first base substrate may include a first flexibility enhancing portion formed in the flexible region, and the second base substrate may include a second flexibility enhancing portion formed in the flexible region.

[0018] The first flexibility enhancing portion may be formed on a surface of the first base substrate on which the first conductive pattern and the pressure sensitive material layer are not disposed. The second flexibility enhancing portion may be formed on a surface of the second base substrate on which the second conductive pattern is not disposed.

[0019] The first flexibility enhancing portion may include at least one first discontinuous portion, and the second flexibility enhancing portion may include at least one second discontinuous portion. The first discontinuous portion may include a first groove having a shape that is concave from one surface of the first base substrate toward another surface of the first base substrate on which the first conductive pattern is disposed. The second discontinuous portion may include a second groove having a shape that is concave from one surface of the second base substrate toward another surface of the second base substrate on which the second conductive pattern is disposed.

[0020] When the curvature of the corresponding curved area is nR (n is a natural number of 1 or more), each of the first groove and the second groove may have a width corresponding to about 2πn. Each of the first grooves and each of the second grooves may be alternately disposed.

[0021] The first groove may have a depth equal to or less than half the thickness of the first base substrate, and the second groove may have a depth equal to or less than half the thickness of the second base substrate.

[0022] The sensor may be disposed on a surface of the display panel opposite to a surface from which light is emitted.

[0023] The pressure-sensitive material layer may be disposed between the first conductive pattern and the second conductive pattern to fill a space between the first conductive pattern and the second conductive pattern.

[0024] According to another aspect of the invention, a display device includes: a display panel; a window disposed on a surface of the display panel from which light is emitted; a polarizing film disposed between the display panel and the window; and a sensor disposed on one surface of the display panel. The sensor includes: a first base substrate including a sensing area, a non-sensing area, and a foldable flexible area, the first base substrate including a first flexibility enhancement portion formed in the flexible area; a plurality of first conductive patterns extending in a first direction in the sensing area of ​​the first base substrate; a second base substrate facing the first base substrate; a plurality of second conductive patterns extending in a second direction intersecting the first conductive patterns disposed on the surface of the first base substrate; a pressure-sensitive material layer disposed between the first conductive pattern and the second conductive pattern, the pressure-sensitive material layer having a resistance that changes in response to pressure; and an adhesive layer connecting the first base substrate and the second base substrate, the adhesive layer and the pressure-sensitive material layer being disposed in the same layer.

[0025] When external pressure is applied to the sensor, the resistance of the pressure-sensitive material layer corresponding to the area to which the pressure has been applied decreases, and the pressure-sensitive material layer may include a polymer compound and conductive particles dispersed in the polymer compound.

[0026] The pressure-sensitive material layer may be disposed along an extension direction of the first conductive patterns in the sensing region, and the pressure-sensitive material layer may overlap each of the first conductive patterns.

[0027] The adhesive layer may include a first adhesive pattern disposed in the sensing region and a second adhesive pattern disposed in the non-sensing region, and the second adhesive pattern may be connected to the first adhesive pattern.

[0028] The first adhesive pattern may be disposed between the spaced-apart adjacent first conductive patterns or between the spaced-apart adjacent second conductive patterns.

[0029] The first adhesive pattern may be disposed along an extending direction of the first conductive pattern or the second conductive pattern, and the second adhesive pattern may be disposed along an edge of the sensing region in the non-sensing region.

[0030] The sensor may be disposed on a surface of the display panel from which light is not emitted.

[0031] The first flexibility enhancing portion may be disposed on a surface of the first base substrate on which the first conductive pattern and the pressure sensitive material layer are not disposed.

[0032] The second base substrate may further include a second flexibility enhancing portion formed in a region corresponding to the flexible region of the first base substrate, and the second flexibility enhancing portion may be formed on a surface of the second base substrate on which the second conductive pattern is not disposed.

[0033] The first flexibility-enhanced portion may include at least one first discontinuous portion, and the second flexibility-enhanced portion may include at least one second discontinuous portion.

[0034] The first discontinuous portion may include a first groove having a shape that is concave from one surface of the first base substrate toward another surface of the first base substrate on which the first conductive pattern is arranged, and the second discontinuous portion may include a second groove having a shape that is concave from one surface of the second base substrate toward another surface of the second base substrate on which the second conductive pattern is arranged.

[0035] The display device may further include a cushion layer disposed on a surface from which light from the display panel is not emitted, the cushion layer including an elastically deformable material.

[0036] The pad layer may include a first surface corresponding to a surface from which light from the display panel is not emitted and a second surface opposite to the first surface, and the sensor may be disposed on the second surface of the pad layer.

[0037] The sensor may be disposed between a surface from which light from the display panel is emitted and the polarizing film.

[0038] The polarizing film may include a first surface corresponding to a surface from which light from the display panel is emitted and a second surface opposite to the first surface, and the sensor may be disposed between the second surface of the polarizing film and the window.

[0039] The window may include a first surface corresponding to a surface from which light from the display panel is emitted and a second surface opposite to the first surface, and the sensor may be disposed on the second surface of the window.

[0040] The first flexibility enhancing portion may include at least one groove having a shape concave from one surface of the first base substrate corresponding to the second surface of the window toward another surface of the first base substrate on which the first conductive pattern is disposed.

[0041] 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

[0042] The accompanying drawings illustrate exemplary embodiments of the invention and together with the description serve to explain the inventive concept. The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification.

[0043] In the accompanying drawings, dimensions are exaggerated for clarity. It will be understood that when an element is referred to as being "between" two elements, the element may be the only element between the two elements, or one or more intermediate elements may also be present. The same reference numerals always represent the same elements.

[0044] Figure 1 is a perspective view of an exemplary embodiment of a display device including a pressure sensor constructed according to the principles of the invention.

[0045] Figure 2 is along Figure 1 A cross-sectional view taken along line II'.

[0046] Figure 3 When Figure 1 A cross-sectional view of the display device when the display device is folded.

[0047] Figure 4 It is schematically shown Figure 1 Plan view of the pressure sensor.

[0048] Figure 5 yes Figure 4 Schematic diagram of the pressure sensor.

[0049] Figure 6 is along Figure 4 A cross-sectional view taken along line II-II'.

[0050] Figure 7 When no pressure is applied to the pressure sensor Figure 6 The enlarged view of the area EA1 corresponds to.

[0051] Figure 8 When pressure is applied to the pressure sensor Figure 6 The enlarged view of the area EA1 corresponds to.

[0052] Fig.9A and Fig. 9B is a plan view illustrating a pressure sensor according to an exemplary embodiment.

[0053] Fig. 10A and Fig. 10B is a plan view showing a pressure sensor according to another exemplary embodiment.

[0054] Fig. 10C It is shown that Fig. 10A a first base substrate and Fig. 10B A plan view of the pressure sensor of the second base substrate.

[0055] Fig. 10D is along Fig. 10C A sectional view taken along line III-III'.

[0056] Fig.11 yes Figure 4 A perspective view of a first conductive pattern and a second conductive pattern shown in FIG.

[0057] Fig.12 yes Figure 4 0026] A perspective view of another exemplary embodiment of a first conductive pattern and a second conductive pattern shown in FIG.

[0058] Fig.13 is a perspective view of a pressure sensor constructed in accordance with another exemplary embodiment of the invention.

[0059] Fig.14 When Fig.13 A cross-sectional view of the pressure sensor when the pressure sensor is folded.

[0060] Fig.15 is along Fig.13 A cross-sectional view taken along line IV-IV'.

[0061] Fig.16A yes Fig.15 Magnified view of area EA2.

[0062] Fig. 16B yes Fig.15 Magnified view of area EA3.

[0063] Fig.17 yes Figure 1 A plan view of a display panel of a display device.

[0064] Fig.18 yes Fig.17 An equivalent circuit diagram of one of the pixels shown in FIG.

[0065] Fig.19 yes Fig.17 A cross-sectional view of a portion of a display panel.

[0066] Fig. 20 Is has Figure 4 0026 is a cross-sectional view of an exemplary embodiment of a display device of a pressure sensor shown in FIG.

[0067] Figure 21 to Figure 25 Is has Figures 13 to 15 A cross-sectional view of a display device of a pressure sensor is shown in FIG. DETAILED DESCRIPTION

[0068] In the following description, for the purpose of explanation, many specific details are set forth to provide a comprehensive understanding of various exemplary embodiments or implementations of the invention. As used herein, "embodiment" and "implementation" are interchangeable words and are non-limiting examples of devices or methods using one or more inventive concepts disclosed herein. However, it is apparent that various exemplary embodiments can be practiced without these specific details or with one or more equivalent arrangements. In other cases, in order to avoid unnecessarily obscuring various exemplary embodiments, known structures and devices are shown in block diagram form. In addition, various exemplary embodiments may be different, but not necessarily exclusive. For example, without departing from the inventive concept, the specific shape, configuration and characteristics of the exemplary embodiment may be used or implemented in another exemplary embodiment.

[0069] Unless otherwise stated, the exemplary embodiments shown will be understood as providing exemplary features of varying details of some ways in which the inventive concept can be actually implemented. Therefore, unless otherwise stated, the features, components, modules, layers, films, panels, regions and / or aspects, etc. (hereinafter, individually or collectively referred to as "elements / elements") of various embodiments can be further combined, separated, interchanged and / or rearranged without departing from the inventive concept.

[0070] Cross hatching and / or shading are generally provided in the drawings so that the boundaries between adjacent elements are clear. Thus, unless otherwise specified, the presence or absence of cross hatching or shading does not convey or indicate any preference or requirement for the specific material, material properties, size, ratio, commonality between the elements shown, and / or any other characteristics, attributes, properties, etc. of the elements. In addition, in the drawings, the size and relative size of the elements are exaggerated for the purpose of clarity and / or description. When the exemplary embodiments can be implemented differently, the specific process sequence can be performed in a different order than described. For example, two continuously described processes can be performed substantially simultaneously or in an order opposite to the described order. In addition, the same reference numerals represent the same elements.

[0071] When an element or layer is referred to as being "on" another element or layer, "connected to" or "bonded to" another element or layer, the element or layer may be directly on, directly connected to or directly bonded to the other element or layer, or there may be an intermediate element or layer. However, when an element or layer is referred to as being "directly on" another element or layer, "directly connected to" or "directly bonded to" another element or layer, there is no intermediate element or layer. For this reason, the term "connection" may represent a physical, electrical and / or fluid connection with or without an intermediate element. In addition, the D1 axis, the D2 axis, and the D3 axis are not limited to the three axes (e.g., the x-axis, the y-axis, and the z-axis) of a rectangular coordinate system, but may be interpreted in a broader sense. For example, the D1 axis, the D2 axis, and the D3 axis may be perpendicular to each other, or may represent different directions that are not perpendicular to each other. For the purpose 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 interpreted as only X, only Y, only Z, or any combination of two or more of X, Y, and Z, such as XYZ, XYY, YZ, and ZZ for example. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0072] 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. Therefore, the first element discussed below may be named as the second element without departing from the disclosed teachings.

[0073] For descriptive purposes, spatially relative terms such as "under," "below," "under," "below," "above," "upper," "above," "higher," and "side" (e.g., as in "sidewall") may be used herein to describe the relationship of one element to another element as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and / or manufacture in addition to the orientation depicted in the accompanying drawings. For example, if the device in the accompanying drawings is flipped, an element described as "under" or "below" other elements or features would subsequently be positioned as "above" the other elements or features. Thus, the exemplary term "under" can include both above and below orientations. In addition, the device can be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and as such, the spatially relative descriptors used herein are interpreted accordingly.

[0074] The terms used here are for the purpose of describing specific embodiments and are not intended to be limited. Unless the context clearly indicates otherwise, as used here, the singular forms "one", "a kind of" and "the (said)" are also intended to include plural forms. In addition, when the terms "include" and / or "comprise" and variations thereof are used in this specification, it is indicated that there are stated features, integral bodies, steps, operations, elements, components and / or their groups, but it is not excluded that there are or add one or more other features, integral bodies, steps, operations, elements, components and / or their groups. It is also noted that, as used here, the terms "substantially", "approximately" and other similar terms are used as approximate terms rather than as terms of degree, and are thus used to explain the inherent deviations in the measured values, calculated values ​​and / or provided values ​​that will be recognized by those of ordinary skill in the art.

[0075] Figure 1 is a perspective view of an exemplary embodiment of a display device including a pressure sensor constructed according to the principles of the invention. Figure 2 is along Figure 1 A cross-sectional view taken along line II'. Figure 3 When Figure 1 A cross-sectional view of the display device when the display device is folded.

[0076] Reference Figures 1 to 3 , the display device DD may include a pressure sensor PSR, a display panel PNL, and a window WD.

[0077] The display device DD may be configured in various shapes. For example, the display device DD may be configured in a rectangular plate shape having two pairs of sides substantially parallel to each other. When the display device DD is configured in a rectangular plate shape, any pair of the two pairs of sides may be longer than the other pair of sides.

[0078] In the exemplary embodiment, for the convenience of description, the display device DD is shown to have a pair of long sides and a pair of short sides. In this case, the extension direction of the long side is represented as a first direction DR1, the extension direction of the short side is represented as a second direction DR2, and the direction perpendicular to the extension direction of the long side and the extension direction of the short side is represented as a third direction DR3.

[0079] At least a portion of the display device DD of the illustrated embodiment may have flexibility, and the display device DD may be folded at the portion having flexibility. That is, the display device DD may include a curved area BA having flexibility and being bendable, and flat areas FA1 and FA2, which are disposed at at least one side of the curved area BA and are flat without being folded. The flat areas FA1 and FA2 may include a first flat area FA1 and a second flat area FA2 separated from each other, and the curved area BA is disposed between the first flat area FA1 and the second flat area FA2. The first flat area FA1 and the second flat area FA2 may have flexibility or may not have flexibility.

[0080] In the illustrated embodiment, the first flat area FA1 , the bent area BA, and the second flat area FA2 are sequentially arranged along the first direction DR1 , but the inventive concept is not limited thereto. The bent area BA may extend along the second direction DR2 .

[0081] When the center line about which the display device DD is folded is the folding line FL, the folding line FL may be provided in plurality and may be provided in the bending area BA. In the illustrated embodiment, if the folding line FL passes through the center of the bending area BA, the bending area BA is axisymmetric with respect to the folding line FL, but the inventive concept is not limited thereto. For example, the folding line FL may be provided asymmetrically in the bending area BA. The bending area BA and the folding line FL may overlap with a display area displaying an image in the display panel PNL. When the display device DD is folded, the display area may be folded.

[0082] The term "folding" as used herein does not mean a fixed shape but means a shape that can be deformed from an original shape to another shape, and includes a shape that is folded, bent, or rolled like a roller along one or more specific lines (i.e., one or more folding lines). Therefore, in an exemplary embodiment, the display device DD is shown to be folded so that one surface of the first flat area FA1 and one surface of the second flat area FA2 are positioned substantially parallel to each other and folded to face each other. However, the inventive concept is not limited thereto. For example, the display device DD can be folded so that the surface of the first flat area FA1 and the surface of the second flat area FA2 form a predetermined angle (e.g., an acute angle, a right angle, or an obtuse angle), and the curved area BA is placed between the first flat area FA1 and the second flat area FA2.

[0083] In addition, in the curved area BA and the first flat area FA1 and the second flat area FA2, the expression "having flexibility" or "having no flexibility" is a term indicating the properties of the display device DD, respectively. That is, the expression "having no flexibility" may include not only a case where it is hard and has no flexibility at all, but also a case where the flexibility is less than that of the curved area BA even if there is flexibility. Therefore, the first flat area FA1 and the second flat area FA2 may have flexibility relatively less than that of the curved area BA or may have no flexibility. Even under the condition that the curved area BA is folded, the first flat area FA1 and the second flat area FA2 may not be folded.

[0084] In the illustrated display device DD, since the folding line FL is provided in the bending area BA, the display device DD may be folded in the bending area BA.

[0085] For ease of description, the first flat area FA1 and the second flat area FA2 have similar areas, and the curved area BA is located between the first flat area FA1 and the second flat area FA2, but the inventive concept is not limited thereto. For example, the first flat area FA1 and the second flat area FA2 may have different areas from each other. In addition, two flat areas FA1 and FA2 each including the first flat area FA1 and the second flat area FA2 will not be provided. In some embodiments, one or three or more flat areas may be provided. In this case, a plurality of separated flat areas may be provided, and the curved area BA is placed between the plurality of separated flat areas.

[0086] The display panel PNL can display any visual information, such as text, video, picture, two-dimensional or three-dimensional image, etc. In the following, any visual information is referred to as "image". The type of display panel PNL is not specifically limited to the type of displayed image. For example, a self-luminous display panel such as an organic light-emitting display panel (OLED panel) can be used as the display panel PNL. In addition, a non-luminous display panel such as a liquid crystal display panel (LCD panel), an electrophoretic display panel (EPD panel) and an electrowetting display panel (EWD panel) can be used as the display panel PNL. When the non-luminous display panel is used as the display panel PNL, the display device DD may include a backlight unit that supplies light to the display panel PNL.

[0087] The display panel PNL may include a display area displaying an image and a non-display area provided at least one side of the display area. For example, the non-display area may be provided in a shape surrounding the display area.

[0088] The pressure sensor PSR may be disposed on the rear surface (i.e., the surface on which the image is not displayed) of the display panel PNL and recognize a touch event from the display device DD by a user's finger or a separate input tool. In an exemplary embodiment, the pressure sensor PSR may sense the position of the touch event and the intensity of the pressure at the position.

[0089] The pressure sensor PSR may include a sensing area SA where a user's touch occurs and a non-sensing area NSA provided at least on one side of the sensing area SA. The non-sensing area NSA may be provided in a shape surrounding the sensing area SA. Here, the sensing area SA may correspond to the display area of ​​the display panel PNL, and the non-sensing area NSA may correspond to the non-display area of ​​the display panel PNL.

[0090] The pressure sensor PSR may include a first conductive pattern and a second conductive pattern and a pressure-sensitive material layer disposed between the first conductive pattern and the second conductive pattern and has a resistance that changes according to a user's touch pressure. Figure 4 Description Pressure sensor PSR.

[0091] Each of the display panel PNL and the pressure sensor PSR in the display device DD may have flat areas FA1 and FA2 and a curved area BA. The curved area BA of the display panel PNL may correspond to the curved area BA of the pressure sensor PSR, and the flat areas FA1 and FA2 of the display panel PNL may correspond to the flat areas FA1 and FA2 of the pressure sensor PSR.

[0092] A window WD for protecting the exposed surface of the display panel PNL may be provided on the display panel PNL. The window WD allows an image from the display panel PNL to be transmitted therethrough while reducing an impact from the outside, so that the display panel PNL can be prevented from being damaged or erroneously operated due to external force.

[0093] Figure 4 It is schematically shown Figure 1 Plan view of the pressure sensor. Figure 5 yes Figure 4 Schematic diagram of the pressure sensor. Figure 6 is along Figure 4 A cross-sectional view taken along line II-II'. Figure 7 When no pressure is applied to the pressure sensor Figure 6 The enlarged view of the area EA1 corresponds to. Figure 8 When pressure is applied to the pressure sensor Figure 6 A magnified view of area EA1. Figure 5 In the present invention, for the convenience of description, the illustration of the adhesive layer included in the pressure sensor is omitted.

[0094] Reference Figures 1 to 8 The display device DD according to the illustrated embodiment may include a pressure sensor PSR, a driving unit DVR, a sensing unit DSR, and a controller COL. The display device DD may be deformed in various shapes so that at least a portion of the display device DD is bent, folded, or curled, etc. To this end, at least some of the components constituting the display device DD may have flexibility.

[0095] The pressure sensor PSR may include a first base substrate BS1, a plurality of first conductive patterns CP1, a second base substrate BS2, and a plurality of second conductive patterns CP2.

[0096] The first base substrate BS1 may include a sensing area SA and a non-sensing area NSA. For ease of description, the sensing area SA of the first base substrate BS1 is referred to as a first sensing area SA, and the non-sensing area NSA of the first base substrate BS1 is referred to as a first non-sensing area NSA.

[0097] In exemplary embodiments, the first base substrate BS1 may be made of a material having flexibility to be bendable or foldable, and have a single-layer structure or a multi-layer structure.

[0098] For example, the material having flexibility may include at least one of polystyrene, polyvinyl alcohol, polymethyl methacrylate, polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, cellulose triacetate, and cellulose acetate propionate. However, various changes may be made to the material constituting the first base substrate BS1, and the first base substrate BS1 may be made of fiber reinforced plastic (FRP) or the like.

[0099] The first conductive patterns CP1 may be disposed on the first base substrate BS1. Specifically, the first conductive patterns CP1 may be disposed in the first sensing area SA, extend along the second direction DR2, and may be repeatedly arranged substantially parallel to each other. In the first sensing area SA, each first conductive pattern CP1 may be separated from adjacent first conductive patterns CP1.

[0100] The first conductive pattern CP1 may include a conductive material. The conductive material may include a metal or an alloy thereof. The metal may include gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium (Nd), copper (Cu), platinum (Pt), etc. In addition, the first conductive pattern CP1 may include a transparent conductive material. The transparent conductive material may include silver nanowires (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 nanotubes and graphene, etc.

[0101] The second base substrate BS2 may include the same material as that of the first base substrate BS1. The second base substrate BS2 may include a sensing area SA and a non-sensing area NSA. The sensing area SA of the second base substrate BS2 may correspond to the first sensing area SA, and the non-sensing area NSA of the second base substrate BS2 may correspond to the first non-sensing area NSA. For ease of description, the sensing area SA included in the second base substrate BS2 is referred to as the second sensing area SA, and the non-sensing area NSA included in the second base substrate BS2 is referred to as the second non-sensing area NSA.

[0102] The second conductive pattern CP2 may be disposed on the second base substrate BS2. Specifically, the second conductive pattern CP2 may be disposed in the second sensing area SA, extending along the first direction DR1 intersecting the second direction DR2, and repeatedly arranged in parallel with each other. In the second sensing area SA, each second conductive pattern CP2 may be separated from an adjacent second conductive pattern CP2. The second conductive pattern CP2 may include a conductive material. The second conductive pattern CP2 may include the same material as the first conductive pattern CP1 or may include a material different from the material of the first conductive pattern CP1.

[0103] In an exemplary embodiment, one of the first conductive pattern CP1 and the second conductive pattern CP2 may be a driving electrode that receives a driving signal applied from the driving unit DVR through a corresponding connection line CL, and the other of the first conductive pattern CP1 and the second conductive pattern CP2 may be a receiving electrode that transmits a touch pressure sensing signal to the sensing unit DSR through a corresponding connection line CL. In an exemplary embodiment, the first conductive pattern CP1 may be a receiving electrode, and the second conductive pattern CP2 may be a driving electrode. Here, the driving signal may be a signal for sensing the touch pressure of the user.

[0104] The driving unit DVR may apply a driving signal to the second conductive pattern CP2. For example, the driving unit DVR may sequentially supply the driving signal to the second conductive pattern CP2. Furthermore, the driving unit DVR may simultaneously apply the driving signal to the second conductive pattern CP2.

[0105] The sensing unit DSR may receive a touch pressure sensing signal from the first conductive pattern CP1. The touch pressure sensing signal may include information about a location where pressure is applied and information about a voltage value or a current value output from the first conductive pattern CP1.

[0106] The controller COL may generate a driving control signal and then transmit the driving control signal to the driving unit DVR. The driving unit DVR receiving the driving control signal may convert the driving control signal into a driving signal of the second conductive pattern CP2 and transmit the driving signal to the second conductive pattern CP2.

[0107] In addition, the controller COL may generate a sensing control signal and then transmit the sensing control signal to the sensing unit DSR. The sensing unit DSR may receive the touch pressure sensing signal transmitted from the first conductive pattern CP1 in response to the sensing control signal.

[0108] Meanwhile, the pressure sensor PSR may further include a pressure-sensitive material layer PSL and an adhesive layer ADL disposed between the first base substrate BS1 and the second base substrate BS2 .

[0109] The pressure-sensitive material layer PSL is a component having electrical characteristics that change according to the degree of deformation of the pressure-sensitive material layer PSL, and the resistance of the pressure-sensitive material layer PSL may change according to the external pressure applied between the first conductive pattern CP1 and the second conductive pattern CP2. That is, the resistance of the pressure-sensitive material layer PSL may change according to the amount of external pressure applied to the pressure sensor PSR. For example, the resistance of the pressure-sensitive material layer PSL may decrease as the pressure increases. Specifically, when no pressure is applied to the display device DD, the resistance of the pressure-sensitive material layer PSL increases significantly, and therefore, the pressure-sensitive material layer PSL may be in an electrically open state.

[0110] In exemplary embodiments, the pressure sensitive material layer PSL may include a polymer material layer (or referred to as a polymer compound) PML and conductive particles CDP uniformly dispersed in the polymer material layer PML.

[0111] Conductive particles CDP may include particles of non-metal, metal, conductive oxide of non-metal or metal or conductive nitride of non-metal or metal, particles in a core-shell structure coated on insulating beads, or a combination thereof. Non-metal may include any one of antimony (Sb), germanium (Ge) and arsenic (As) or an alloy thereof. Metal may include zinc (Zn), aluminum (Al), scandium (Sc), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), indium (In), tin (Sn), yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), palladium (Pd), gold (Au), silver (Ag), platinum (Pt), strontium (Sr), tungsten (W), cadmium (Cd), tantalum (Ta), titanium (Ti) or an alloy thereof. Conductive oxide may include indium tin oxide (ITO), indium zinc oxide (IZO), aluminum-doped zinc oxide (AZO), gallium indium zinc oxide (GIZO), zinc oxide (ZnO) and a mixture thereof.

[0112] In an exemplary embodiment, the conductive particles CDP may include metal particles, but the inventive concept is not limited thereto. The conductive particles CDP may have a diameter of about 100 nm to about 1000 nm.

[0113] The polymer material layer PML may be a polymer resin including a material having elasticity to be elastically deformed according to a user's touch. In an exemplary embodiment, the material having elasticity may be deformed by external pressure (e.g., pressure applied by a user's finger, a stylus pen, etc.), and may have elasticity such that the material can return to an original state when the external pressure is removed. The polymer material layer PML may include any one selected from polycarbonate (PC), polymethyl methacrylate (PMMA), polyimide (PI), polyethylene terephthalate (PET), polypropylene terephthalate (PPT), amorphous polyethylene terephthalate (APET), polyethylene naphthalate (PEN), ethylene glycol-modified polyethylene terephthalate (PETG), triacetyl cellulose (TAC), cycloolefin polymer (COP), cycloolefin copolymer (COC), polydicyclopentadiene (DCPD), cyclopentadiene anion (CPD), polyarylate (PAR), polyethersulfone (PES), polyetherimide (PEI), modified epoxy resin and acrylic resin, or any combination of two or more thereof. In an exemplary embodiment, the polymer material layer PML may include polymethyl methacrylate (PMMA).

[0114] The pressure sensitive material layer PSL formed of a polymer material layer PML in which conductive particles CDP are uniformly dispersed may be applied on the first conductive pattern CP1 using a screen printing method or the like.

[0115] In an exemplary embodiment, the pressure-sensitive material layer PSL may be disposed between the first conductive pattern CP1 and the second conductive pattern CP2 to fill the space between the first conductive pattern CP1 and the second conductive pattern CP2. That is, the pressure-sensitive material layer PSL may fill the space between the first conductive pattern CP1 and the second conductive pattern CP2 to remove an air gap that may exist in the space.

[0116] like Figure 8 As shown in , if a touch occurs when the user's finger 10 contacts the pressure sensor PSR, pressure may be applied to the pressure sensor PSR. The substrate (e.g., the second base substrate BS2) may be deformed. If the second base substrate BS2 is deformed, the distance between the second conductive pattern CP2 and the first conductive pattern CP1 may be reduced.

[0117] In addition, if pressure is applied to the pressure sensor PSR, the electrical characteristics (i.e., resistance) of the pressure-sensitive material layer PSL corresponding to the area where the pressure is applied decreases. In addition, as the pressure-sensitive material layer PSL deforms, the distance between the second conductive pattern CP2 and the first conductive pattern CP1 decreases. Specifically, if the resistance of the pressure-sensitive material layer PSL decreases, current flows between the second conductive pattern CP2 and the first conductive pattern CP1, and the distance between the second conductive pattern CP2 and the first conductive pattern CP1 decreases. The pressure sensor PSR can use the current flowing between the first conductive pattern CP1 and the second conductive pattern CP2 to sense the intensity of the user's touch pressure applied to the pressure sensor PSR. At the same time, the pressure sensor PSR can sense the user's touch position.

[0118] The adhesive layer ADL may include a first adhesive pattern ADP1 and a second adhesive pattern ADP2.

[0119] The first adhesive pattern ADP1 may be disposed in the first sensing area SA and the second sensing area SA, and the second adhesive pattern ADP2 may be disposed in the first non-sensing area NSA and the second non-sensing area NSA. In an exemplary embodiment, the first adhesive pattern ADP1 and the second adhesive pattern ADP2 may contact each other to be connected to each other. For example, the first adhesive pattern ADP1 may be disposed in the first sensing area SA and the second sensing area SA in a shape extending from the second adhesive pattern ADP2. Figure 4 As shown in FIG. 1 , the first adhesive pattern ADP1 may be disposed in the first and second sensing areas SA to extend in the first direction DR1 and may be disposed between two adjacent second conductive patterns CP2 .

[0120] The first and second adhesive patterns ADP1 and ADP2 may be disposed between the first and second base substrates BS1 and BS2 to adhere the first and second base substrates BS1 and BS2 to each other. In addition, the first and second adhesive patterns ADP1 and ADP2 may additionally remove an air gap remaining in the space between the first and second base substrates BS1 and BS2.

[0121] In an exemplary embodiment, the first adhesive pattern ADP1 may have a thickness d3 that is smaller than a value obtained by adding the thickness d1 of the first conductive pattern CP1 and the thickness d2 of the pressure-sensitive material layer PSL. For example, when a value obtained by adding the thickness d1 of the first conductive pattern CP1 and the thickness d2 of the pressure-sensitive material layer PSL is 12 μm, the first adhesive pattern ADP1 may have a thickness d3 of about 10 μm.

[0122] When viewed in a plane, one first adhesive pattern ADP1 may be disposed between two adjacent second conductive patterns CP2. By considering adhesion tolerance, etc., the first adhesive pattern ADP1 may have a width smaller than the distance between two adjacent second conductive patterns CP2, but the inventive concept is not limited thereto. For example, the first adhesive pattern ADP1 may have a width equal to the distance between two adjacent second conductive patterns CP2. In this case, the first adhesive pattern ADP1 may fill between two adjacent second conductive patterns CP2.

[0123] When viewed in a plane, the second adhesive pattern ADP2 may have a shape extending along edges of the first and second sensing areas SA and SA.

[0124] In an exemplary embodiment, the adhesive layer ADL may include a pressure-sensitive adhesive (PSA) including an adhesive material that reacts when pressure is applied to allow the adhesive layer ADL to adhere to the adhesive surface. When the adhesive layer ADL includes the PSA, the adhesive layer ADL may be attached to the adhesive surface using only pressure without requiring a separate heat treatment or UV treatment at normal temperature.

[0125] Fig.9A and Fig. 9B is a plan view illustrating a pressure sensor according to an exemplary embodiment. Fig. 10A and Fig. 10B is a plan view showing a pressure sensor according to another exemplary embodiment. Fig. 10C It is shown that Fig. 10A a first base substrate and Fig. 10B A plan view of the pressure sensor of the second base substrate. Fig. 10D is along Fig. 10C A sectional view taken along line III-III'. Fig.11 yes Figure 4 A perspective view of a first conductive pattern and a second conductive pattern shown in FIG. Fig.12 yes Figure 4 0026] A perspective view of another exemplary embodiment of a first conductive pattern and a second conductive pattern shown in FIG.

[0126] Reference Figure 4 , Fig.9A , Fig. 9B , Fig. 10A , Fig. 10B , Fig. 10C , Fig. 10D , Fig.11 and Fig.12The pressure sensor PSR according to the illustrated embodiment may include a first base substrate BS1, a plurality of first conductive patterns CP1 and a pressure-sensitive material layer PSL disposed on the first base substrate BS1, a second base substrate BS2, and a plurality of second conductive patterns CP2 and an adhesive layer ADL disposed on the second base substrate BS2.

[0127] In an exemplary embodiment, the first conductive pattern CP1 may extend along the second direction DR2 and may be disposed on the first base substrate BS1 so that each of the first conductive patterns CP1 is separated from an adjacent first conductive pattern CP1 by a specific distance. As shown in the drawings, the first conductive pattern CP1 may have a bar (columnar) shape. However, the inventive concept is not limited thereto, and the first conductive pattern CP1 may have various shapes. For example, the first conductive pattern CP1 may have an irregular or regular shape such as a polygonal shape including a quadrilateral shape similar to a rhombus. Each of the first conductive patterns CP1 may be connected to a sensing unit (see Figure 5 of DSR).

[0128] The pressure-sensitive material layer PSL may be applied onto the corresponding first conductive patterns CP1 and cover the first conductive patterns CP1. When viewed in a plane, the pressure-sensitive material layer PSL may overlap the first conductive patterns CP1.

[0129] In an exemplary embodiment, the second conductive patterns CP2 may extend in the first direction DR1 crossing the second direction DR2 and may be disposed on the second base substrate BS2 such that each of the second conductive patterns CP2 is spaced apart from adjacent second conductive patterns CP2 by a certain distance.

[0130] As shown in the drawings, similar to the first conductive pattern CP1, the second conductive pattern CP2 may have a bar (columnar) shape. However, the inventive concept is not limited thereto, and the second conductive pattern CP2 may have various shapes. For example, the second conductive pattern CP2 may have an irregular or regular shape such as a polygonal shape including a quadrilateral similar to a rhombus. In some embodiments, as Fig.12 As shown in , the second conductive pattern CP2 may have a polygonal shape including a plurality of protrusions protruding in one direction. In this case, the second conductive pattern CP2 may have a shape more complex than that of the first conductive pattern CP1. If the second conductive pattern CP2 has a complex shape, the visibility from the outside of the first conductive pattern CP1 and the pressure-sensitive material layer PSL, etc., which are disposed under the second conductive pattern CP2, can be reduced, which is undesirable.

[0131] The adhesive layer ADL may include a first adhesive pattern ADP1 disposed in the sensing area SA of the second base substrate BS2 and a second adhesive pattern ADP2 disposed in the non-sensing area NSA of the second base substrate BS2. The first adhesive pattern ADP1 may extend in an extension direction of the second conductive pattern CP2 and may be separated from the adjacent second conductive pattern CP2 by a specific distance. The first adhesive pattern ADP1 may extend from the second adhesive pattern ADP2 to the sensing area SA.

[0132] like Fig. 9B As shown in , when viewed in a plane, the adhesive layer ADL does not overlap with the second conductive pattern CP2. When the first base substrate BS1 and the second base substrate BS2 are bonded together using the adhesive layer ADL, the first adhesive pattern ADP1 and the first conductive pattern CP1 may partially overlap each other in a region where they cross each other, and the first adhesive pattern ADP1 and the second conductive pattern CP2 may not overlap each other.

[0133] In the above-described embodiment, it is illustrated that the adhesive layer ADL is disposed on the second base substrate BS2 , but the inventive concept is not limited thereto.

[0134] In some embodiments, Fig. 10A , Fig. 10C and Fig. 10D As shown in , the adhesive layer ADL may be disposed on the first base substrate BS1. In this case, the first adhesive pattern ADP1 of the adhesive layer ADL may extend in the extension direction of the first conductive pattern CP1 and may be spaced apart from the adjacent first conductive pattern CP1 by a certain distance. Fig. 10A As shown in , the first adhesive pattern ADP1 may be disposed between adjacent first conductive patterns CP1 among the first conductive patterns CP1. Fig. 10B , Fig. 10C and Fig. 10D As shown in FIG. 1 , only the second conductive pattern CP2 may be disposed on the second base substrate BS2. Fig. 10C and Fig. 10DAs shown in, when the first base substrate BS1 and the second base substrate BS2 are bonded together using the adhesive layer ADL, the first adhesive pattern ADP1 and the second conductive pattern CP2 may partially overlap each other at the intersection of the first adhesive pattern ADP1 and the second conductive pattern CP2, and the first adhesive pattern ADP1 and the first conductive pattern CP1 may not overlap each other. In addition, the pressure-sensitive material layer PSL and the adhesive layer ADL may not overlap each other in the sensing area SA of the first base substrate BS1 and the second base substrate BS2. The pressure-sensitive material layer PSL may be disposed between the first conductive pattern CP1 and the second conductive pattern CP2 in the sensing area SA of the first base substrate BS1 and the second base substrate BS2. The pressure-sensitive material layer PSL may fill the space between the first conductive pattern CP1 and the second conductive pattern CP2 to remove the air gap that may exist in the space.

[0135] Fig.13 is a perspective view of a pressure sensor constructed in accordance with another exemplary embodiment of the invention. Fig.14 When Fig.13 A cross-sectional view of the pressure sensor when the pressure sensor is folded. Fig.15 is along Fig.13 A cross-sectional view taken along line IV-IV'. Fig.16A yes Fig.15 A magnified view of area EA2, Fig. 16B yes Fig.15 In another exemplary embodiment, only the difference from the above-described embodiment will be mainly described to avoid redundancy. In this embodiment, the parts not specifically described in this embodiment follow the parts of the above-described embodiment. In addition, the same reference numerals represent the same components, and similar reference numerals represent similar components.

[0136] Reference Figures 13 to 15 , Fig.16A and Fig. 16B , the pressure sensor PSR according to the illustrated embodiment may include a first base substrate BS1, a plurality of first conductive patterns CP1, a pressure-sensitive material layer PSL, a second base substrate BS2, a plurality of second conductive patterns CP2, and an adhesive layer ADL.

[0137] At least a portion of the pressure sensor PSR may have flexibility, and the pressure sensor PSR may be folded at the portion having flexibility. The pressure sensor PSR may include a bending area BA having flexibility and being bendable, and first and second flat areas FA1 and FA2, which are disposed at at least one side of the bending area BA and are not folded. The first and second flat areas FA1 and FA2 may have flexibility.

[0138] When a center line about which the pressure sensor PSR is folded is a folding line FL, the folding line FL may be provided in plural and may be provided in the bending area BA.

[0139] The first base substrate BS1 may be made of a material having flexibility so as to be foldable. The first base substrate BS1 may include a sensing area SA and a non-sensing area NSA. The first conductive pattern CP1 may be arranged in the sensing area SA of the first base substrate BS1. The first conductive pattern CP1 may be connected to the sensing unit (see FIG. 1 ) through a connecting line CL arranged in the non-sensing area NSA of the first base substrate BS1. Figure 5 of DSR).

[0140] The second base substrate BS2 may also be made of a material having flexibility so as to be foldable. The second base substrate BS2 may include a sensing area SA corresponding to the sensing area SA of the first base substrate BS1 and a non-sensing area NSA corresponding to the non-sensing area NSA of the first base substrate BS1. The second conductive pattern CP2 may be arranged in the sensing area SA of the second base substrate BS2. The second conductive pattern CP2 may be connected to the driving unit (see FIG. 1 ) through the connecting line CL arranged in the non-sensing area NSA of the second base substrate BS2. Figure 5 DVR).

[0141] The pressure-sensitive material layer PSL and the adhesive layer ADL may be disposed between the first base substrate BS1 and the second base substrate BS2 .

[0142] The pressure-sensitive material layer PSL is a component having electrical characteristics that change according to the degree of deformation of the pressure-sensitive material layer PSL, and the resistance of the pressure-sensitive material layer PSL may change according to the external pressure applied between the first conductive pattern CP1 and the second conductive pattern CP2. That is, the resistance of the pressure-sensitive material layer PSL may change according to the external pressure applied to the pressure sensor PSR. For example, the resistance of the pressure-sensitive material layer PSL may decrease as the pressure increases.

[0143] The pressure-sensitive material layer PSL may be disposed between the first conductive pattern CP1 and the second conductive pattern CP2 and fill the space between the first conductive pattern CP1 and the second conductive pattern CP2 to remove the air gap that may exist in the space. The air gap may keep the first conductive pattern CP1 and the second conductive pattern CP2 separated from each other by a specific distance and serve as a factor that prevents the space between the first conductive pattern CP1 and the second conductive pattern CP2 from narrowing. If the air gap is removed when the pressure-sensitive material layer PSL deformed by the pressure applied to the pressure-sensitive material layer PSL is disposed between the first conductive pattern CP1 and the second conductive pattern CP2, the distance between the first conductive pattern CP1 and the second conductive pattern CP2 may be easily reduced. Therefore, if external pressure is applied to the pressure sensor PSR, the distance between the first conductive pattern CP1 and the second conductive pattern CP2 is reduced by the applied pressure, so that current may flow between the first conductive pattern CP1 and the second conductive pattern CP2. The pressure sensor PSR may sense the user's touch pressure and the position of the touch pressure using the current flowing between the first conductive pattern CP1 and the second conductive pattern CP2.

[0144] The first base substrate BS1 may include a bending area BA and first and second flat areas FA1 and FA2. The first base substrate BS1 may be folded so that the first and second flat areas FA1 and FA2 face each other about a folding line FL.

[0145] The second base substrate BS2 may also include a bent area BA and first and second flat areas FA1 and FA2.

[0146] When the pressure sensor PSR is folded along the folding line FL, bending breakage may occur where the first and second base substrates BS1 and BS2 break due to stress applied to the pressure sensor PSR. To reduce bending breakage, it is advantageous to improve the impact resistance characteristics of the first and second base substrates BS1 and BS2.

[0147] To this end, the pressure sensor PSR according to an exemplary embodiment may include a first flexibility enhancing portion HP1 and a second flexibility enhancing portion HP2. As an example, the first flexibility enhancing portion HP1 and the second flexibility enhancing portion HP2 are described herein as a first groove portion and a second groove portion, but any shape, structure or material that enhances flexibility may be used.

[0148] The first groove portion HP1 may be disposed in the bending area BA of the first base substrate BS1. Specifically, the first groove portion HP1 may be disposed on a surface of the first base substrate BS1 corresponding to the bending area BA and where the first conductive pattern CP1 and the pressure-sensitive material layer PSL are not disposed. For example, the first groove portion HP1 may be disposed on the rear surface of the first base substrate BS1.

[0149] In an exemplary embodiment, the first groove portion HP1 may include one or more discontinuous portions such as grooves TRE1 that contribute to flexibility. The first grooves TRE1 may be regularly or irregularly disposed on the rear surface of the first base substrate BS1. However, from the perspective of ease of manufacturing the first base substrate BS1, the first grooves TRE1 may preferably be regularly disposed on the rear surface of the first base substrate BS1.

[0150] As shown in the drawings, each first groove TRE1 may have a semi-elliptical shape including a Gaussian shape, but the inventive concept is not limited thereto. For example, each first groove TRE1 may have various shapes including a semicircular shape, a conical shape, a trapezoidal shape, a circular shape, a polygonal shape, and a quadrilateral shape. The width W1 of each first groove TRE1 may be about 20 μm to about 30 μm, but the inventive concept is not limited thereto. In addition, the distance W2 between adjacent first grooves TRE1 may be about 100 μm to about 200 μm, but the inventive concept is not limited thereto.

[0151] Each first groove TRE1 may be dug from the rear surface of the first base substrate BS1 toward the top surface of the first base substrate BS1 on which the first conductive pattern CP1 is located. By considering the reliability of the first base substrate BS1, each first groove TRE1 may be dug from the rear surface of the first base substrate BS1 toward the top surface to have a depth d4 equal to or less than half the thickness of the first base substrate BS1.

[0152] Due to the first trench portion HP1 including the first groove TRE1 , the rear surface of the first base substrate BS1 may include a surface having unevenness.

[0153] The second groove portion HP2 may be disposed in the bending area BA of the second base substrate BS2. Specifically, the second groove portion HP2 may be disposed on a surface of the bending area BA of the second base substrate BS2 on which the second conductive pattern CP2 is not disposed. For example, the second groove portion HP2 may be disposed on the top surface of the second base substrate BS2.

[0154] In an exemplary embodiment, the second groove portion HP2 may include one or more discontinuous portions that contribute to flexibility, such as the second groove TRE2. The second groove TRE2 may be regularly or irregularly disposed on the top surface of the second base substrate BS2. From the perspective of easy manufacture of the second base substrate BS2, the second groove TRE2 may be regularly disposed on the top surface of the second base substrate BS2.

[0155] As shown in the drawings, each second groove TRE2 may have a semi-elliptical shape, but the inventive concept is not limited thereto. For example, each second groove TRE2 may have various shapes including a semicircular shape, a conical shape, a trapezoidal shape, a circular shape, a polygonal shape, and a quadrilateral shape. The width W3 of each second groove TRE2 may be about 20 μm to about 30 μm, but the inventive concept is not limited thereto. In addition, the distance W4 between adjacent second grooves TRE2 may be about 100 μm to about 200 μm, but the inventive concept is not limited thereto.

[0156] Each second groove TRE2 may be dug from the top surface of the second base substrate BS2 toward the rear surface of the second base substrate BS2 on which the second conductive pattern CP2 is positioned. At this time, by considering the reliability of the second base substrate BS2, each second groove TRE2 may be dug from the top surface of the second base substrate BS2 toward the rear surface to have a depth d5 ​​equal to or less than half the thickness of the second base substrate BS2.

[0157] Due to the second trench portion HP2 including the second groove TRE2 , the top surface of the second base substrate BS2 may include a surface having unevenness.

[0158] Each first groove TRE1 and each second groove TRE2 may be provided on the corresponding base substrate using a laser or the like, and may be provided to cross each other when viewed in a vertical direction. That is, each first groove TRE1 and each second groove TRE2 may be provided alternately when viewed in a vertical direction. However, the inventive concept is not limited thereto, and each first groove TRE1 and each second groove TRE2 may be provided to correspond to each other in a vertical direction.

[0159] When the pressure sensor PSR is folded along the folding line FL, Fig.14 As shown in , the bending area BA may be a circular shape having a predetermined radius R so as to be foldable with a predetermined radius of curvature.

[0160] In an exemplary embodiment, the width W1 of each first groove TRE1 may be determined according to the curvature of the bending area BA of the first base substrate BS1, and the width W3 of the second groove TRE2 may be determined according to the curvature of the bending area BA of the second base substrate BS2. For example, when the curvature of the bending area BA of the first base substrate BS1 is nR (n is a natural number of 1 or more), the width W1 of each first groove TRE1 may be about 2πn. In addition, when the curvature of the bending area BA of the second base substrate BS2 is nR (n is a natural number of 1 or more), the width W3 of each second groove TRE2 may be about 2πn.

[0161] When the pressure sensor PSR is folded along the folding line FL, the stress applied to the first base substrate BS1 and the second base substrate BS2 is not concentrated in the folding direction, but can be dispersed through the first groove portion HP1 and the second groove portion HP2. Therefore, it is possible to reduce the phenomenon that the pressure sensor PSR is broken due to fatigue due to the stress applied to the pressure sensor PSR when the pressure sensor PSR is folded. Therefore, the durability of the pressure sensor PSR can be improved.

[0162] According to an exemplary embodiment, when sensing pressure caused by a user's touch, the pressure sensor PSR senses the user's touch position and the intensity of the touch pressure, so that the reliability of the pressure sensor PSR may be improved.

[0163] Fig.17 yes Figure 1 A plan view of a display panel of a display device.

[0164] Reference Figure 1 and Fig.17 , the display panel PNL according to the exemplary embodiment may display an image. In the exemplary embodiment, the display panel PNL may be an organic light emitting display panel (OLED panel).

[0165] The display panel PNL may include a substrate SUB, pixels PXL, a driving unit, a power supply unit, a line unit, and the like.

[0166] The substrate SUB may include a display area DA and a non-display area NDA. The display area DA is an area where pixels PXL for displaying an image are provided, and may correspond to a sensing area SA of the pressure sensor PSR. The non-display area NDA is an area where pixels PXL are not provided, and an image is not displayed in the non-display area NDA. The non-display area NDA may be provided with a driving unit for driving the pixels PXL, a power supply unit for applying power to the pixels PXL, and some lines for connecting the pixels PXL and the driving unit. The non-display area NDA may correspond to a non-sensing area NSA of the pressure sensor PSR.

[0167] Each pixel PXL is a minimum unit for displaying an image, and a plurality of pixels PXL may be provided in the display area DA. In an exemplary embodiment, the pixel PXL may include an organic light emitting device. The pixel PXL may emit light of one color among red, green, blue, and white, but the inventive concept is not limited thereto. For example, the pixel PXL may emit light of one color among cyan, magenta, and yellow, etc.

[0168] The driving unit provides a signal to each pixel PXL through the line unit, and thus, driving of each pixel PXL may be controlled.

[0169] The driving unit may include a scan driver SDV, an emission driver EDV, a data driver DDV, and a timing controller. The scan driver SDV is used to provide a scan signal to each pixel PXL through a scan line, the emission driver EDV is used to provide an emission control signal to each pixel PXL through an emission control line, and the data driver DDV is used to provide a data signal to each pixel PXL through a data line. The timing controller may control the scan driver SDV, the emission driver EDV, and the data driver DDV.

[0170] The power supply unit may include at least one power line. For example, the power supply unit may include a first power line and a second power line (not shown). The power supply unit may supply power to each of the pixels PXL arranged in the display area DA.

[0171] Fig.18 yes Fig.17 0 is an equivalent circuit diagram of one of the pixels shown in 0. In order to facilitate description and avoid redundancy, the pixel and the lines connected to the pixel are mainly shown.

[0172] Reference Fig.17 and Fig.18 Each pixel PXL may include a transistor connected to the line, an organic light emitting element OLED connected to the transistor, and a capacitor Cst. The organic light emitting element OLED may be a top emission organic light emitting element or a bottom emission organic light emitting element. The organic light emitting element OLED may be an organic light emitting diode.

[0173] Each pixel PXL has a pixel driving circuit for driving the organic light emitting element OLED, and may include a first transistor (or switching transistor) T1, a second transistor (or driving transistor) T2, and a capacitor Cst. A first power source ELVDD may be provided to the second transistor T2 through a power line PL, and a second power source ELVSS may be provided to the organic light emitting element OLED. The second power source ELVSS may be set to a voltage lower than the voltage of the first power source ELVDD.

[0174] The first transistor T1 outputs a data signal applied to the data line DL in response to a scan signal applied to the gate line GL. The capacitor Cst charges a voltage corresponding to the data signal received from the first transistor T1. The second transistor T2 is connected to the organic light emitting element OLED. The second transistor T2 controls a driving current flowing through the organic light emitting element OLED corresponding to the amount of charge stored in the capacitor Cst.

[0175] In the exemplary embodiment, it is shown that one pixel PXL includes two transistors T1 and T2. However, the inventive concept is not limited thereto, and one pixel PXL may include one transistor and one capacitor, or three or more transistors and two or more capacitors. For example, one pixel PXL may include seven transistors, an organic light emitting element OLED, and a capacitor Cst.

[0176] Fig.19 yes Fig.17 A cross-sectional view of a portion of a display panel.

[0177] Reference Fig.17 and Fig.19 , the display panel PNL according to the illustrated embodiment may include a substrate SUB, a pixel circuit unit PCL, a display element layer DPL, and a thin film encapsulation layer TFE.

[0178] The substrate SUB may be made of a material having flexibility to be bendable or foldable, and have a single-layer structure or a multi-layer structure.

[0179] The pixel circuit unit PCL may include a buffer layer BFL disposed on a substrate SUB and a first transistor T1 and a second transistor T2 disposed on the buffer layer BFL.

[0180] The buffer layer BFL may prevent impurities from diffusing into the first transistor T1 and the second transistor T2. The buffer layer BFL may be provided as a single layer, but may also be provided as a multilayer including at least two layers. When the buffer layer BFL is provided as a multilayer, the multilayer may be formed of the same material or may be formed of different materials. The buffer layer BFL may be omitted according to the material of the substrate SUB and process conditions.

[0181] The first transistor T1 may be a switching transistor for switching the second transistor T2. The second transistor T2 may be a driving transistor electrically connected to the organic light emitting element OLED of the display element layer DPL to drive the organic light emitting element OLED.

[0182] The first transistor T1 may include a first semiconductor layer SCL1, a first gate electrode GE1, a first source electrode SE1, and a first drain electrode DE1. The second transistor T2 may include a second semiconductor layer SCL2, a second gate electrode GE2, a second source electrode SE2, and a second drain electrode DE2.

[0183] The first semiconductor layer SCL1 and the second semiconductor layer SCL2 may be disposed on the buffer layer BFL. The first semiconductor layer SCL1 and the second semiconductor layer SCL2 may include a source region and a drain region contacting the first source electrode SE1 and the second source electrode SE2 and the first drain electrode DE1 and the second drain electrode DE2, respectively. The region between the source region and the drain region may be a channel region. Each of the first semiconductor layer SCL1 and the second semiconductor layer SCL2 may be a semiconductor pattern made of polycrystalline silicon, amorphous silicon, an oxide semiconductor, or the like. The channel region is a semiconductor pattern not doped with impurities and may be an intrinsic semiconductor. The source region and the drain region are semiconductor patterns doped with impurities. The impurities may include impurities such as n-type impurities, p-type impurities, and other metals.

[0184] The first gate electrode GE1 may be disposed on the first semiconductor layer SCL1 with the gate insulating layer GI interposed therebetween. The second gate electrode GE2 may be disposed on the second semiconductor layer SCL2 with the gate insulating layer GI interposed therebetween.

[0185] The first source electrode SE1 and the first drain electrode DE1 may respectively contact the source region and the drain region of the first semiconductor layer SCL1 through contact holes passing through the interlayer insulating layer ILD and the gate insulating layer GI. The second source electrode SE2 and the second drain electrode DE2 may respectively contact the source region and the drain region of the second semiconductor layer SCL2 through contact holes passing through the interlayer insulating layer ILD and the gate insulating layer GI.

[0186] A protection layer PSV may be disposed on the first transistor T1 and the second transistor T2 .

[0187] The display element layer DPL may include an organic light emitting element OLED disposed on the protective layer PSV. The organic light emitting element OLED may include a first electrode AE, a second electrode CE, and an emission layer EML disposed between the two electrodes AE and CE. Here, any one of the first electrode AE ​​and the second electrode CE may be an anode electrode, and the other of the first electrode AE ​​and the second electrode CE may be a cathode electrode. For example, the first electrode AE ​​may be an anode electrode, and the second electrode CE may be a cathode electrode. When the organic light emitting element OLED is a top emission type organic light emitting element, the first electrode AE ​​may be a reflective electrode, and the second electrode CE may be a transmissive electrode. In an exemplary embodiment, a case where the organic light emitting element OLED is a top emission type organic light emitting element and the first electrode AE ​​is an anode electrode is described as an example.

[0188] The first electrode AE ​​may be connected to the second source electrode SE2 of the second transistor T2 through a contact hole passing through the protective layer PSV. The first electrode AE ​​may include a reflective layer capable of reflecting light and a transparent conductive layer disposed on the top or bottom of the reflective layer. At least one of the transparent conductive layer and the reflective layer may be connected to the second source electrode SE2.

[0189] The display element layer DPL may further include a pixel defining layer PDL having an opening OP allowing a portion of the first electrode AE ​​(eg, a top surface of the first electrode AE) to be exposed through the opening OP.

[0190] The pixel defining layer PDL may include an organic insulating material. For example, the pixel defining layer PDL may include at least one of polystyrene, polymethyl methacrylate (PMMA), polyacrylonitrile (PAN), polyamide (PA), polyimide (PI), polyarylether (PAE), heterocyclic polymer, polyparaxylene, epoxy resin, benzocyclobutene (BCB), siloxane resin, and silane resin.

[0191] The emission layer EML may be disposed on the exposed surface of the first electrode AE.

[0192] The emission layer EML may include a low molecular weight material or a high molecular weight material. In an exemplary embodiment, the low molecular weight material may include copper phthalocyanine (CuPc), N,N'-bis(1-naphthyl)-N,N'-diphenyl-benzidine (NPB), and tris-8-hydroxyquinoline aluminum (Alq 3 ) etc. The polymer material may include poly(3,4-ethylenedioxythiophene) (PEDOT), poly(phenylene-vinylene) (PPV), and poly(fluorine) materials.

[0193] The emission layer EML can be set as a single layer, or as a multilayer including various functional layers. When the emission layer EML is set as a multilayer, the emission layer EML can have a structure in which a hole injection layer, a hole transport layer, an emission layer, an electron transport layer, and an electron injection layer are stacked in a single structure or a composite structure. The inventive concept is not necessarily limited to this, and the emission layer EML can have various structures. In addition, at least a portion of the emission layer EML can be formed integrally throughout a plurality of first electrodes AE, or can be individually set to correspond to each of the plurality of first electrodes AE. The color of the light generated in the emission layer EML can be one of red, green, blue, and white, but the inventive concept is not limited thereto. For example, the color of the light generated in the light generating layer of the emission layer EML can be one of magenta, cyan, and yellow.

[0194] The second electrode CE may be disposed on the emission layer EML. The second electrode CE may be a semi-transmissive reflective layer. For example, the second electrode CE may be a thin metal layer having a thickness through which light emitted by the emission layer EML may be transmitted. The second electrode CE may transmit a portion of the light emitted from the emission layer EML, and may reflect the remaining portion of the light emitted from the emission layer EML.

[0195] The thin film encapsulation layer TFE may be disposed on the organic light emitting element OLED.

[0196] The thin film encapsulation layer TFE may be provided as a single layer, or may be provided as a multilayer. The thin film encapsulation layer TFE may include a plurality of insulating layers covering the organic light emitting element OLED. Specifically, the thin film encapsulation layer TFE may include a plurality of inorganic layers and a plurality of organic layers. For example, the thin film encapsulation layer TFE may have a structure in which inorganic layers and organic layers are alternately stacked. In addition, in some cases, the thin film encapsulation layer TFE may be an encapsulation substrate provided on the organic light emitting element OLED and bonded to the substrate SUB through a sealant.

[0197] Fig. 20 Is has Figure 4 0026 is a cross-sectional view of an exemplary embodiment of a display device of a pressure sensor shown in FIG.

[0198] Reference Figures 1 to 4 and Fig. 20 , the display device DD according to the illustrated embodiment may include a pressure sensor PSR, a display panel PNL, and a window WD.

[0199] The display panel PNL may include a substrate SUB, a pixel circuit unit PCL disposed on the substrate SUB, a display element layer DPL connected to the pixel circuit unit PCL, and a thin film encapsulation layer TFE disposed on the display element layer DPL.

[0200] The pixel circuit unit PCL may include at least one transistor T and a protection layer PSV covering the transistor T. The transistor T may include a semiconductor layer SCL, a gate electrode GE, a source electrode SE, and a drain electrode DE. The semiconductor layer SCL may include a source region and a drain region doped or injected with impurities and a channel region disposed between the two regions.

[0201] The display element layer DPL may include an organic light emitting element OLED disposed on the pixel circuit unit PCL. The organic light emitting element OLED may include a first electrode AE, a second electrode CE, and an emission layer EML disposed between the two electrodes AE and CE.

[0202] The thin film encapsulation layer TFE may be disposed on the organic light emitting element OLED to isolate the organic light emitting element OLED from the external environment. For example, the thin film encapsulation layer TFE may prevent external moisture and oxygen from penetrating into the organic light emitting element OLED.

[0203] The window WD may have a shape corresponding to the display panel PNL. In addition, the window WD may have a plate shape including two surfaces. The window WD may include a material that enables light to be transmitted therethrough. For example, the window WD may be made of a transparent polymer resin having flexibility, etc. The window WD may prevent the display panel PNL from being damaged due to external impact.

[0204] The polarizing film POL may be disposed between the display panel PNL and the window WD. The polarizing film POL may prevent external light from being reflected from the display panel PNL. For example, the polarizing film POL may include a linear polarizer and a retardation layer disposed on the linear polarizer.

[0205] In an exemplary embodiment, the pressure sensor PSR may be disposed on one of the surfaces of the display panel PNL (eg, a surface opposite to the surface in the light emitting direction). The pressure sensor PSR may include a first base substrate BS1, a plurality of first conductive patterns CP1, a second base substrate BS2, and a plurality of second conductive patterns CP2.

[0206] Each of the first base substrate BS1 and the second base substrate BS2 may be made of a material having flexibility to be bendable or foldable, and have a single-layer structure or a multi-layer structure.

[0207] The first conductive pattern CP1 may be disposed in the sensing area SA of the first base substrate BS1. The second conductive pattern CP2 may be disposed on one surface (eg, a surface facing the first conductive pattern CP1) of the second base substrate BS2. In addition, the second conductive pattern CP2 may be disposed in the sensing area SA of the second base substrate BS2.

[0208] The pressure sensor PSR may further include a pressure-sensitive material layer PSL and an adhesive layer ADL disposed between the first base substrate BS1 and the second base substrate BS2 .

[0209] The resistance of the pressure-sensitive material layer PSL may change according to the pressure applied to the pressure sensor PSR. For example, the resistance of the pressure-sensitive material layer PSL may decrease as the pressure increases.

[0210] The pressure sensitive material layer PSL may be disposed between the first conductive pattern CP1 and the second conductive pattern CP2 to fill the space therebetween. That is, the pressure sensitive material layer PSL may fill the space therebetween to remove air gaps that may exist therein.

[0211] The adhesive layer ADL may include a first adhesive pattern ADP1 and a second adhesive pattern ADP2. The first adhesive pattern ADP1 may be disposed in the sensing area SA, and the second adhesive pattern ADP2 may be disposed in the non-sensing area NSA. The first adhesive pattern ADP1 and the second adhesive pattern ADP2 may additionally remove an air gap remaining in a space between the first base substrate BS1 and the second base substrate BS2.

[0212] If pressure is applied to the pressure sensor PSR when a user touches, the resistance of the pressure-sensitive material layer PSL corresponding to the area where the pressure is applied decreases. The display device DD according to an exemplary embodiment can sense the user's touch pressure and the user's touch position at the same time by sensing a change in resistance.

[0213] In the following, reference will be made to Figure 21 to Figure 25 Description has Figures 13 to 15 An embodiment of a display device of a pressure sensor is shown in FIG.

[0214] Fig.21 and Fig. 22 Is has Figures 13 to 15 A cross-sectional view of a display device of a pressure sensor is shown in FIG. Fig.21 and Fig. 22 In the display device of the present invention, parts different from those of the display device according to the above-described embodiment will be mainly described to avoid redundancy.

[0215] First, refer to Figures 13 to 15 and Fig.21 , a display device according to an exemplary embodiment may include a pressure sensor PSR, a display panel PNL, a polarizing film POL, and a window WD.

[0216] The display panel PNL includes a plurality of pixels (see Fig.17 PXL) to provide a predetermined image.

[0217] The display panel PNL may display an image on at least one surface thereof. In an exemplary embodiment, for ease of description, a case where an image is displayed on the top surface of the display panel PNL is shown. The top surface on which the image is displayed may be a flat surface without curvature or a curved surface with a predetermined curvature. Alternatively, the top surface on which the image is displayed may be set to a temporarily flat but bendable or rollable shape. In an exemplary embodiment, the top surface of the display panel PNL may refer to a surface from which light is emitted.

[0218] The type of the display panel PNL for displaying an image is not particularly limited. For example, the display panel PNL may be an OLED panel.

[0219] The polarizing film POL may be disposed on the top surface of the display panel PNL. The polarizing film POL may prevent external light from being reflected by the display panel PNL.

[0220] The window WD may be disposed on the polarizing film POL. The window WD is disposed on the top surface of the display panel PNL (ie, the surface on which an image is displayed) and is located at the outermost side of the upper surface of the display device, thereby being able to protect the display device from external stress or impact.

[0221] The pressure sensor PSR may be disposed on the rear surface of the display panel PNL. The pressure sensor PSR may include a first base substrate BS1, a plurality of first conductive patterns CP1, a pressure sensitive material layer PSL, a second base substrate BS2, a plurality of second conductive patterns CP2, and an adhesive layer ADL.

[0222] The first base substrate BS1 and the second base substrate BS2 may be made of a material having flexibility so as to be foldable. The first conductive pattern CP1 may be arranged in the sensing area SA of the first base substrate BS1, and the second conductive pattern CP2 may be arranged in the sensing area SA of the second base substrate BS2. The pressure-sensitive material layer PSL is a component having electrical characteristics that change according to the degree of deformation of the pressure-sensitive material layer PSL, and the resistance of the pressure-sensitive material layer PSL may change according to the external pressure applied between the first conductive pattern CP1 and the second conductive pattern CP2. An adhesive layer ADL may be provided between the first base substrate BS1 and the second base substrate BS2 to allow the first base substrate BS1 and the second base substrate BS2 to adhere to each other.

[0223] The pressure sensor PSR may include a first flexibility reinforced portion such as the first groove portion HP1 and a second flexibility reinforced portion such as the second groove portion HP2 , the first flexibility reinforced portion and the second flexibility reinforced portion being used to improve anti-shock characteristics.

[0224] The first groove portion HP1 may be disposed in the bending area BA of the first base substrate BS1, and the second groove portion HP2 may be disposed in the bending area BA of the second base substrate BS2. In an exemplary embodiment, the first groove portion HP1 may be disposed on the rear surface of the first base substrate BS1, and the second groove portion HP2 may be disposed on the top surface of the second base substrate BS2. The first groove portion HP1 may include a plurality of discontinuous portions that contribute to flexibility, such as a first groove TRE1 having a shape that is deeply dug from the rear surface of the first base substrate BS1 toward the top surface of the first base substrate BS1. The second groove portion HP2 may include a plurality of discontinuous portions that contribute to flexibility, such as a second groove TRE2 having a shape that is deeply dug from the top surface of the second base substrate BS2 toward the rear surface of the second base substrate BS2.

[0225] The display device may further include a cushion layer CSL disposed between the display panel PNL and the pressure sensor PSR. The cushion layer CSL may be disposed on a rear surface of the display panel PNL (i.e., a surface on which no image is displayed). In an exemplary embodiment, the rear surface of the display panel PNL may refer to a surface from which light is not emitted. Therefore, the cushion layer CSL may be disposed on a surface from which light of the display panel PNL is not emitted.

[0226] The cushion layer CSL may include a material that can be deformed by an external impact or a user's touch pressure. That is, the cushion layer CSL may include an elastically deformable material. The cushion layer CSL may include polyurethane or polyurethane foam. A display device including the cushion layer CSL may more effectively absorb an external impact.

[0227] In exemplary embodiments, since the cushion layer CSL is disposed on the pressure sensor PSR, the second groove portion HP2 may be disposed between the rear surface of the cushion layer CSL and the top surface of the second base substrate BS2 .

[0228] In some embodiments, Fig. 22 As shown in , the cushion layer CSL can be omitted in the display device. In this case, the pressure sensor PSR provided on the bottom of the display panel PNL can be used as the cushion layer CSL. When the pressure sensor PSR is used as the cushion layer CSL, the thickness of the display device can be reduced. Therefore, a thin thickness can be achieved for the display device.

[0229] Fig.23 and Fig.24 It shows that the Figures 13 to 15 A cross-sectional view of an embodiment of a display device of a pressure sensor is shown in FIG. Fig.23 and Fig.24 In the display device of the present invention, parts different from those of the display device according to the above-described embodiment will be mainly described to avoid redundancy.

[0230] Reference Figures 13 to 15 , Fig.23 and Fig.24 , a display device according to an exemplary embodiment may include a cushion layer CSL, a display panel PNL, a pressure sensor PSR, a polarizing film POL, and a window WD.

[0231] The cushion layer CSL may be disposed on the bottom of the display panel PNL to protect the display panel PNL from external impact.

[0232] The display panel PNL may display an image on a top surface thereof. The display panel PNL may be disposed between the cushion layer CSL and the pressure sensor PSR.

[0233] The polarizing film POL may be disposed on the display panel PNL.

[0234] The window WD may be disposed on the polarizing film POL.

[0235] The pressure sensor PSR may include a first base substrate BS1, a plurality of first conductive patterns CP1, a pressure sensitive material layer PSL, a second base substrate BS2, a plurality of second conductive patterns CP2, and an adhesive layer ADL. As discussed above, the pressure sensor PSR may include first and second trench portions HP1 and HP2.

[0236] like Fig.23 As shown in , the pressure sensor PSR may be disposed between the display panel PNL and the polarizing film POL. That is, the pressure sensor PSR may be disposed on the top surface of the display panel PNL. In this case, the top surface of the second base substrate BS2 may correspond to the rear surface of the polarizing film POL, and the rear surface of the first base substrate BS1 may correspond to the top surface of the display panel PNL (i.e., the surface on which an image is displayed and from which light is emitted).

[0237] The first groove portion HP1 may correspond to the bending area BA of the first base substrate BS1 and may be disposed between the top surface of the display panel PNL and the rear surface of the first base substrate BS1. The first groove portion HP1 may include a plurality of first grooves TRE1 having a shape deeply dug from the top surface of the display panel PNL toward the top surface of the first base substrate BS1, and the top surface of the display panel PNL corresponds to the rear surface of the first base substrate BS1.

[0238] The second groove portion HP2 may correspond to the bending area BA of the second base substrate BS2 and may be disposed between the rear surface of the polarizing film POL and the top surface of the second base substrate BS2. The second groove portion HP2 may include a plurality of second grooves TRE2 having a shape that is deeply dug from the rear surface of the polarizing film POL toward the rear surface of the second base substrate BS2, and the rear surface of the polarizing film POL corresponds to the top surface of the second base substrate BS2.

[0239] In an exemplary embodiment, the first conductive pattern CP1 and the second conductive pattern CP2 included in the pressure sensor PSR may be made of a transparent conductive material so as not to affect an image emitted from the display panel PNL. For example, the transparent conductive material may include 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 nanotubes and graphene, etc.

[0240] Specifically, when the first and second conductive patterns CP1 and CP2 are made of a transparent conductive material, an image emitted from the display panel PNL may be finally emitted from the window WD without light loss due to the pressure sensor PSR.

[0241] In some embodiments, Fig.24 As shown in , the pressure sensor PSR may be disposed between the window WD and the polarizing film POL. In this case, the top surface of the second base substrate BS2 may correspond to the rear surface of the window WD, and the rear surface of the first base substrate BS1 may correspond to the top surface of the polarizing film POL. The second groove portion HP2 corresponding to the curved area BA of the second base substrate BS2 may include a second groove TRE2 having a shape deeply dug from the rear surface of the window WD toward the rear surface of the second base substrate BS2, and the rear surface of the window WD corresponds to the top surface of the second base substrate BS2. The first groove portion HP1 corresponding to the curved area BA of the first base substrate BS1 may include a first groove TRE1 having a shape deeply dug from the top surface of the polarizing film POL toward the top surface of the first base substrate BS1, and the top surface of the polarizing film POL corresponds to the rear surface of the first base substrate BS1.

[0242] Fig.25 It shows that the Figures 13 to 15 A cross-sectional view of an embodiment of a display device of a pressure sensor is shown in FIG. Fig.25 In the display device of the present invention, parts different from those of the display device according to the above-described exemplary embodiment will be mainly described to avoid redundancy.

[0243] Reference Figures 13 to 15 and Fig.25 , a display device according to an exemplary embodiment may include a cushion layer CSL, a display panel PNL, a polarizing film POL, a window WD, and a pressure sensor PSR.

[0244] The cushion layer CSL may be disposed on the bottom of the display panel PNL to protect the display panel PNL from external impact.

[0245] The display panel PNL may display an image on a top surface thereof. The display panel PNL may be disposed on the cushion layer CSL.

[0246] The polarizing film POL may be disposed on the display panel PNL.

[0247] The window WD may be disposed on the polarizing film POL.

[0248] The pressure sensor PSR may be disposed on the window WD. The pressure sensor PSR may include a first base substrate BS1, a plurality of first conductive patterns CP1, a pressure-sensitive material layer PSL, a second base substrate BS2, a plurality of second conductive patterns CP2, and an adhesive layer ADL. In addition, the pressure sensor PSR may include a groove portion HP disposed in the first base substrate BS1.

[0249] The first and second conductive patterns CP1 and CP2 included in the pressure sensor PSR may be made of a transparent conductive material so as to have no influence on an image emitted from the display panel PNL.

[0250] In an exemplary embodiment, the rear surface of the first base substrate BS1 may correspond to the top surface of the window WD. In this case, the groove portion HP may correspond to the bending area BA of the first base substrate BS1 and include a plurality of grooves TRE having a shape deep-dug from the top surface of the window WD toward the top surface of the first base substrate BS1, and the top surface of the window WD corresponds to the rear surface of the first base substrate BS1.

[0251] In an exemplary embodiment, since the second base substrate BS2 of the pressure sensor PSR is disposed in the uppermost layer of the display device, an impact from the outside is directly applied to the second base substrate BS2. Therefore, the second base substrate BS2 may be made of a strong impact-resistant material to protect the display device from external impact.

[0252] In addition, the second base substrate BS2 may not include a component corresponding to the groove portion HP of the first base substrate BS1. When the second base substrate BS2 includes a component corresponding to the groove portion HP, if an impact from the outside is applied to the second base substrate BS2, the component may be easily damaged. Specifically, cracks and the like may occur around the component. As the cracks develop to the entire surface of the second base substrate BS2, defects of the second base substrate BS2 may be caused. Therefore, when the pressure sensor PSR is provided in the uppermost layer of the display device, the second base substrate BS2 may not include a component corresponding to the groove portion HP provided in the first base substrate BS1.

[0253] The display device according to the exemplary embodiment can be used in various electronic devices. For example, the display device can be applied to televisions, notebook computers, cellular phones, smart phones, smart tablets, PMPs, PDAs, navigation and various wearable devices such as smart watches, etc.

[0254] According to an exemplary embodiment, a display device having a pressure sensor can be provided, which facilitates functions requiring the location and / or intensity of a touch input and can reduce the thickness of the display device, which can contribute to the flexibility of a foldable device. For example, an adhesive layer connecting the opposing substrates of the display device can be provided in the same layer as a pressure-sensitive material in the pressure sensor.

[0255] Although specific exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Therefore, as will be apparent to one of ordinary skill in the art, the inventive concept is not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements.

Claims

1. A display device, comprising: Display panel; as well as a sensor disposed on one surface of the display panel to detect external pressure, The sensor has a sensing area and a non-sensing area, and includes: a first base substrate, which is flexible and includes a flexible area, and the first base substrate includes a first flexible reinforcement portion formed in the sensing area; a plurality of first conductive patterns, which extend in a first direction in the sensing area of ​​the first base substrate; a second base substrate, which faces the first base substrate, is flexible and includes a flexible area, and the second base substrate includes a second flexible reinforcement portion formed in the sensing area; a plurality of second conductive patterns, which extend in a second direction intersecting with the first conductive patterns arranged on the surface of the first base substrate; a pressure-sensitive material layer, which is arranged between the first conductive pattern and the second conductive pattern, and the pressure-sensitive material layer has a resistance that changes in response to pressure; and an adhesive layer, which connects the first base substrate and the second base substrate, and the adhesive layer and the pressure-sensitive material layer are arranged in the same layer.

2. The display device according to claim 1, wherein: When external pressure is applied to the sensor, the resistance of the pressure-sensitive material layer corresponding to the area where the pressure is applied decreases.

3. The display device according to claim 2, wherein: The pressure-sensitive material layer includes a polymer compound and conductive particles dispersed in the polymer compound.

4. The display device according to claim 1, wherein: The adhesive layer includes a first adhesive pattern disposed in the sensing area and a second adhesive pattern disposed in the non-sensing area, the second adhesive pattern being connected to the first adhesive pattern.

5. The display device according to claim 1, wherein: The first portion with enhanced flexibility includes at least one first discontinuous portion, and the second portion with enhanced flexibility includes at least one second discontinuous portion.

6. The display device according to claim 1, wherein: The pressure-sensitive material layer is disposed between the first conductive pattern and the second conductive pattern to fill a space between the first conductive pattern and the second conductive pattern.

7. A display device, comprising: Display panel; a window disposed on a surface of the display panel from which light is emitted; a polarizing film disposed between the display panel and the window; as well as a sensor disposed on one surface of the display panel and having a sensing area and a non-sensing area, The sensor comprises: a first base substrate, which is flexible and includes a flexible area, and the first base substrate includes a first flexible reinforcement portion formed in the sensing area; a plurality of first conductive patterns, which extend in a first direction in the sensing area of ​​the first base substrate; a second base substrate, which faces the first base substrate, is flexible and includes a flexible area, and the second base substrate includes a second flexible reinforcement portion formed in the sensing area; a plurality of second conductive patterns, which extend in a second direction intersecting the first conductive patterns arranged on the surface of the first base substrate; a pressure-sensitive material layer, which is arranged between the first conductive patterns and the second conductive patterns, and the pressure-sensitive material layer has a resistance that changes in response to pressure; and an adhesive layer, which connects the first base substrate and the second base substrate, and the adhesive layer and the pressure-sensitive material layer are arranged in the same layer.

8. The display device according to claim 7, wherein: When external pressure is applied to the sensor, the resistance of the pressure-sensitive material layer corresponding to the area where the pressure is applied decreases, and The pressure-sensitive material layer includes a polymer compound and conductive particles dispersed in the polymer compound.

9. The display device according to claim 7, wherein: The second flexibility enhancing portion is formed on a surface of the second base substrate on which the second conductive pattern is not provided.

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