Patent Publication Number: US-2022231239-A1

Title: Display device

Description:
This application claims priority to Korean Patent Application No. 10-2021-0007786, filed on Jan. 20, 2021, and all the benefits accruing therefrom under 35 U.S.C. § 119, the content of which in its entirety is herein incorporated by reference. 
     BACKGROUND 
     1. Field 
     Embodiments of the invention herein relate to a display device. 
     2. Description of the Related Art 
     Electronic devices, such as a smart phone, a digital camera, a notebook computer, a navigation system, and a smart television, which provide images to users, include a display device for displaying images. The display device generates images and provides the images to users through a display screen. 
     With a recent technological development of display devices, various types of display devices are being developed. Various flexible display devices, which may be transformed into a curved, folded or rolled shape, for example, are being developed. The flexible display devices, which may be transformed into various shapes, are easy to carry and improve the convenience of users. 
     Among the flexible display devices, a foldable display device includes a display module that is folded along a folding axis extending in one direction. The display module is folded or unfolded around the folding axis. The display module includes a folding region that is bent during folding. A technology that enables the folding region to be more easily folded may be desired. 
     SUMMARY 
     Embodiments of the invention provide a display device having a folding region which may be more easily folded. 
     An embodiment of the invention provides a display device including a display module and a support plate disposed on the display module and including a plurality of first fibers and a plurality of second fibers disposed on the plurality of first fibers and crossing the plurality of first fibers in a plan view. An opening is defined in the support plate and includes first sides parallel to the plurality of first fibers and facing each other, and second sides parallel to the plurality of second fibers and facing each other. 
     In an embodiment of the invention, a display device may include a display module including a first non-folding region, a second non-folding region, and a folding region disposed between the first and second non-folding regions, and a support plate disposed on the display module and includes a plurality of first fibers extending in a first diagonal direction and arranged in a second diagonal direction crossing the first diagonal direction, and a plurality of second fibers disposed at a location different from a location of the plurality of first fibers in a thickness direction, extending in the second diagonal direction, and arranged in the first diagonal direction. An opening overlapping the folding region is defined in the support plate and includes first sides extending in the first diagonal direction and facing each other in the second diagonal direction and second sides extending in the second diagonal direction and facing each other in the first diagonal direction. 
     In an embodiment of the invention, a display device may include a display module extending in a first direction and foldable around a folding axis parallel to a second direction crossing the first direction, and a support plate disposed on the display module and includes a plurality of first fibers extending in a first diagonal direction crossing the first and second directions and a plurality of second fibers disposed at a location different from a location of the plurality of first fibers in a thickness direction, and extending in a second diagonal direction crossing the first diagonal direction. Openings overlapping the folding region are defined in the support plate and arranged in the first diagonal direction and the second diagonal direction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain principles of the invention. In the drawings: 
         FIG. 1  is a perspective view of an embodiment of a display device according to the invention; 
         FIG. 2  illustrates a folded state of the display device illustrated in  FIG. 1 ; 
         FIG. 3  is a perspective view of an embodiment of a display device according to the invention; 
         FIG. 4  illustrates a folded state of the display device illustrated in  FIG. 3 ; 
         FIG. 5  is a cross-sectional view taken along line illustrated in  FIG. 1 ; 
         FIG. 6  illustrates, as an example, a cross section of the display panel illustrated in  FIG. 5 ; 
         FIG. 7  is a plane view of the display panel illustrated in  FIG. 5 ; 
         FIG. 8  illustrates a folded state of the display device illustrated in  FIG. 5 ; 
         FIG. 9  is a plane view of the support plate illustrated in  FIG. 5 ; 
         FIG. 10  is an enlarged view of the first region AA 1  illustrated in  FIG. 9 ; 
         FIG. 11  is a cross-sectional view taken along line II-II′ illustrated in  FIG. 10 ; 
         FIG. 12  is an enlarged view of the second region AA 2  illustrated in  FIG. 9 ; 
         FIG. 13  is a cross-sectional view taken along line III-III′ illustrated in  FIG. 12 ; 
         FIG. 14  is an enlarged view of the third region AA 3  illustrated in  FIG. 9 ; 
         FIG. 15  illustrates a plane configuration of a support plate according to a comparative embodiment; 
         FIGS. 16 to 18  illustrate configurations of openings according to various extension directions of the first and second fibers illustrated in  FIG. 9 ; and 
         FIGS. 19 and 20  illustrate various shapes of the openings illustrated in  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION 
     In this specification, it will be understood that when an element or layer is referred to as being “on”, “connected to” or “coupled to” another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present. 
     Like reference numerals refer to like elements throughout. In addition, in the drawings, the thicknesses, ratios, and dimensions of elements are exaggerated for effective description of the technical contents. As used herein, the term “and/or” includes any and all combinations that the associated configurations can define. 
     It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the invention. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms, “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. 
     Spatially relative terms, such as “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the drawing figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the drawing figures. For example, if the device in the drawing figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     It will be understood that the terms “include”, “including”, and/or “have”, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     “About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” can mean within one or more standard deviations, or within ±30%, 20%, 10%, 5% of the stated value. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     Hereinafter, the invention will be explained in detail with reference to the accompanying drawings. 
       FIG. 1  is a perspective view of an embodiment of a display device according to the invention.  FIG. 2  illustrates a folded state of the display device illustrated in  FIG. 1 . 
     Referring to  FIG. 1 , the display device DD in an embodiment of the invention may have a quadrangular (e.g., rectangular) shape having long sides extending in a first direction DR 1  and short sides extending in a second direction DR 2  crossing the first direction DR 1 . However, without being limited thereto, the display device DD may have various shapes such as a circle and a polygon. The display device DD may be a flexible display device. 
     Hereinafter, a direction substantially perpendicular to a plane defined by the first direction DR 1  and the second direction DR 2  is defined as a third direction DR 3 . In addition, in this specification, the expression “in a plan view” may be defined as a state of being viewed in the third direction DR 3 . 
     The display device DD may include a folding region FA and a plurality of non-folding regions NFA 1  and NFA 2 . The non-folding regions NFA 1  and NFA 2  may include a first non-folding region NFA 1  and a second non-folding region NFA 2 . The folding region FA may be disposed between the first non-folding region NFA 1  and the second non-folding region NFA 2 . The first non-folding region NFA 1 , the folding region FA, and the second non-folding region NFA 2  may be arranged in the first direction DR 1 . 
     Although one folding region FA and two non-folding regions NFA 1  and NFA 2  are illustrated, the number of the folding region FA and the non-folding regions NFA 1  and NFA 2  is not limited thereto. In an embodiment, the display device DD may include more than two non-folding regions and a plurality of folding regions disposed between the non-folding regions, for example. 
     The upper surface of the display device DD may be defined as a display surface DS and have a plane defined by the first direction DR 1  and the second direction DR 2 . Images IM generated in the display device DD may be provided to users through the display surface DS. 
     The display surface DS may include a display region DA and a non-display region NDA around the display region DA. The display region DA may display images, and the non-display region NDA may not display images. The non-display region NDA may surround the display region DA and define a border of the display device DD printed in a predetermined color. 
     Referring to  FIG. 2 , the display device DD may be a foldable display device DD that is folded or unfolded. In an embodiment, the folding region FA may be bent along a folding axis FX parallel to the second direction DR 2  so that the display device DD is folded, for example. The folding axis FX may be defined as a short axis parallel to a short side of the display device DD. 
     When the display device DD is folded, the first non-folding region NFA 1  and the second non-folding region NFA 2  may face each other, and the display device DD may be in-folded so that the display surface DS is not exposed to the outside. 
       FIG. 3  is a perspective view of an embodiment of a display device according to the invention.  FIG. 4  illustrates a folded state of the display device illustrated in  FIG. 3 . 
     Except for folding operation, the display device DD_ 1  illustrated in  FIG. 3  may have substantially the same configuration as the display device DD illustrated in  FIG. 1 . Accordingly, hereinafter, mostly, the folding operation of the display device DD_ 1  will be described. 
     Referring to  FIGS. 3 and 4 , the display device DD_ 1  may include a folding region FA′ and a plurality of non-folding regions NFA 1 ′ and NFA 2 ′. The non-folding regions NFA 1 ′ and NFA 2 ′ may include a first non-folding region NFA 1 ′ and a second non-folding region NFA 2 ′. The folding region FA′ nay be disposed between the first non-folding region NFA 1 ′ and the second non-folding region NFA 2 ′. The first non-folding region NFA 1 ′, the folding region FA 1 , and the second non-folding region NFA 2 ′ may be arranged in the second direction DR 2 . 
     The folding region FA′ may be bent along a folding axis FX′ parallel to the first direction DR 1  so that the display device DD_ 1  is folded. The folding axis FX′ may be defined as a long axis parallel to a long side of the display device DD_ 1 . The display device DD illustrated in  FIG. 1  may be folded along the short axis, whereas the display device DD_ 1  illustrated in  FIG. 3  may be folded along the long axis. The display device DD_ 1  may be in-folded so that the display surface DS is not exposed to the outside. 
     Although the display devices that are in-folded are illustrated, the invention are not limited thereto. In an embodiment, the display devices DD and DD_ 1  may be out-folded respectively along the folding axes FX and FX′ so that the display surfaces DS are exposed to the outside. 
     Hereinafter, as an example, the display device DD that is in-folded along the folding axis FX parallel to a short axis will be described. 
       FIG. 5  is a cross-sectional view taken along line illustrated in  FIG. 1 . 
     Referring to  FIG. 5 , the display device DD may include a display module DM and a support plate SPT disposed below the display module DM. The display module DM may include a first on-folding region NFA 1 , a second non-folding region NFA 2 , and a folding region FA disposed between the first and second non-folding regions NFA 1  and NFA 2 . The folding region FA may be folded around the folding axis FX described above. 
     The support plate SPT may support the display module DM below the display module DM. In a plan view, a plurality of openings OP may be defined in the support plate SPT and overlap the folding region FA of the display module DM. A portion of the support plate SPT overlapping the folding region FA may be defined as a folding portion FP. The openings OP may be defined in the folding portion FP. 
     The support plate SPT may include carbon fiber reinforced plastic (“CFRP”). In an embodiment, the support plate SPT may include plastic and a plurality of carbon fibers disposed inside the plastic. The CFRP may be lighter than metal. Since the support plate SPT including the CFRP is used to support the display module DM, the display device DD may be lightened. 
     The display module DM may include a display panel DP, an input sensing unit ISP, a reflection prevention layer RPL, a window WIN, a window protection layer WP, a panel protection layer PPL, a cushion layer CUL, and first to sixth adhesive layers AL 1  to AL 6 . 
     The display panel DP in an embodiment of the invention may be a light-emitting display panel. In an embodiment, the display panel DP may be an organic light-emitting display panel or a quantum dot light-emitting display panel, for example. A light-emitting layer of the organic light-emitting display panel may include an organic light-emitting material. A light-emitting layer of the quantum dot light-emitting display panel may include quantum dots, quantum rods, or the like. Hereinafter, the display panel DP is described as an organic light-emitting display panel. 
     The display panel DP may be a flexible display panel. Like the display module DM, the display panel DP may include a first non-folding region NFA 1 , a folding region FA, and a second non-folding region NFA 2 . The display panel DP may include a plurality of pixels for displaying images. The pixels may include organic light-emitting elements. 
     The input sensing unit ISP may be disposed on the display panel DP. The input sensing unit ISP may include a plurality of sensors (not illustrated) for sensing an external input. The sensors may sense external inputs in a capacitive method. When the display device DD is manufactured, the input sensing unit ISP may be manufactured directly on the display panel DP. However, without being limited thereto, the input sensing unit ISP may be manufactured as a panel independent of the display panel DP and then attached to the display panel DP by an adhesive layer. 
     The reflection prevention layer RPL may be disposed on the display panel DP. The reflection prevention layer RPL may be defined as an external light reflection prevention film. The reflection prevention layer RPL may reduce the reflectance of external light incident from above the display device DD toward the display panel DP. 
     When external light traveling toward the display panel DP is reflected like a mirror from the display panel DP and provided again to an external user, the user may visually recognize external light. In order to prevent such a phenomenon, as an example, the reflection prevention layer RPL may include a plurality of color filters that display the same colors as those of the pixels. 
     The color filters may filter external light so as to display the same colors as those of the pixels. In this case, external light may not be visible to a user. However, without being limited thereto, the reflection prevention layer RPL may include a retarder and/or a polarizer for reducing the reflectance of external light. 
     The window WIN may be disposed on the reflection prevention layer RPL. The window WIN may protect the display panel DP, the input sensing unit ISP, and the reflection prevention layer RPL from external scratch. The window WIN may have optically transparent properties. In an embodiment, the window WIN may include glass. The window WIN may be defined as ultra-thin glass (“UTG”). However, without being limited thereto, the window WIN may include a synthetic resin film. 
     The window protection layer WP may be disposed on the window WIN. The window protection layer WP may protect the window WIN. In an embodiment, the window protection layer WP may include a flexible plastic material such as polyimide (“PI”) or polyethylene terephthalate (“PET”). Although not illustrated, a hard coating layer may be further disposed on the window protection layer WP. In addition, an anti-fingerprint layer or an anti-scattering layer defined as a functional layer may be further disposed on the window protection layer WP. 
     The panel protection layer PPL may be disposed below the display panel DP. The panel protection layer PPL may protect the lower portion of the display panel DP from external scratch. The panel protection layer PPL may include a flexible plastic material. In an embodiment, the panel protection layer PPL may include polyethylene terephthalate, for example. 
     The cushion layer CUL may be disposed below the panel protection layer PPL. The cushion layer CUL may protect the display module DM by absorbing an external shock applied to the lower portion of the display module DM. The cushion layer CUL may include a foam sheet having a predetermined elasticity. The cushion layer CUL may include foam, sponge, polyurethane, or thermoplastic polyurethane. 
     The first adhesive layer AL 1  may be disposed between the window protection layer WP and the window WIN. The window protection layer WP and the window WIN may be bonded to each other by the first adhesive layer AL 1 . 
     The second adhesive layer AL 2  may be disposed between the window WIN and the reflection prevention layer RPL. The window WIN and the reflection prevention layer RPL may be bonded to each other by the second adhesive layer AL 2 . 
     The third adhesive layer AL 3  may be disposed between the reflection prevention layer RPL and the input sensing unit ISP. The reflection prevention layer RPL and the input sensing unit ISP may be bonded to each other by the third adhesive layer AL 3 . 
     The fourth adhesive layer AL 4  may be disposed between the display panel DP and the panel protection layer PPL. The display panel DP and the panel protection layer PPL may be bonded to each other by the fourth adhesive layer AL 4 . 
     The fifth adhesive layer AL 5  may be disposed between the panel protection layer PPL and the cushion layer CUL. The panel protection layer PPL and the cushion layer CUL may be bonded to each other by the fifth adhesive layer AL 5 . 
     The sixth adhesive layer AL 6  may be disposed between the cushion layer CUL and the support plate SPT. The cushion layer CUL and the support plate SPT may be bonded to each other by the sixth adhesive layer AL 6 . 
     In an embodiment, the first to sixth adhesive layers AL 1  to AL 6  may include a pressure sensitive adhesive (“PSA”), or a transparent adhesive such as an optically clear adhesive (“OCA”). 
       FIG. 6  illustrates, as an example, a cross section of the display panel illustrated in  FIG. 5 . 
     Referring to  FIG. 6 , the display panel DP may include a substrate SUB, a circuit element layer DP-CL disposed on the substrate SUB, a display element layer DP-OLED disposed on the circuit element layer DP-CL, and a thin-film encapsulation layer TFE disposed on the display element layer DP-OLED. 
     The substrate SUB may include a display region DA and a non-display region NDA around the display region DA. The substrate SUB may include a flexible plastic material. In an embodiment, the substrate may include PI, for example. 
     The display element layer DP-OLED may be disposed on the display region DA. The thin-film encapsulation layer TFE may be disposed on the circuit element layer DP-CL so as to cover the display element layer DP-OLED. A plurality of pixels may be disposed in the circuit element layer DP-CL and the display element layer DP-OLED. In an embodiment, each of the pixels may include a transistor disposed in the circuit element layer DP-CL and a light-emitting element disposed in the display element layer DP-OLED and connected to the transistor, for example. 
     When the display panel DP is manufactured, the input sensing unit ISP may be manufactured directly on the thin-film encapsulation layer TFE. However, without being limited thereto, the input sensing unit ISP may be manufactured as a panel independent of the display panel DP and then attached to the thin-film encapsulation layer TFE by an adhesive layer. 
       FIG. 7  is a plane view of the display panel illustrated in  FIG. 5 . 
     Referring to  FIG. 7 , the display device DD may include a display panel DP, a scan driver SDV, a data driver DDV, alight emission driver EDV, and a plurality of pads PD. 
     The display panel DP may have a quadrangular (e.g., rectangular) shape having long sides extending in the first direction DR 1  and short sides extending in the second direction DR 2 , but the shape of the display panel DP is not limited thereto. The display panel DP may include a display region DA and a non-display region NDA surrounding the display region DA. 
     The display panel DP may include a plurality of pixels PX, a plurality of scan lines SL 1  to plurality of data lines DL 1  to DLn, a plurality of light emission lines EL 1  to ELm, first and second control lines CSL 1  and CSL 2 , first and second power lines PL 1  and PL 2 , and connection lines CNL. Here, “m” and “n” are natural numbers. 
     The pixels PX may be disposed in the display region DA. The scan driver SDV and the light emission driver EDV respectively adjacent to the long sides of the display panel DP may be disposed in the non-display region NDA. The data driver DDV adjacent to one of the short sides of the display panel DP may be disposed in the non-display region NDA. In a plan view, the data driver DDV may be adjacent to the lower end of the display panel DP. 
     The scan lines SL 1  to SLm may extend in the second direction DR 2  to be connected to the scan driver SDV. The data lines DL 1  to DLn may extend in the first direction DR 1  to be connected to the pixels PX and the data driver DDV. The light emission lines EL 1  to ELm may extend in the second direction DR 2  to be connected to the pixels PX and the light emission driver EDV. 
     The first power line PL 1  may extend in the first direction DR 1  to be disposed in the non-display region NDA. The first power line PL 1  may be disposed between the display region DA and the light emission driver EDV. However, without being limited thereto, the first power line PL 1  may be disposed between the display region DA and the scan driver SDV. 
     The connection lines CNL may extend in the second direction DR 2  and be arranged in the first direction DR 1 . The connection lines CNL may be connected to the first power line PL 1  and the pixels PX. A first voltage may be applied to the pixels PX through the first power line PL 1  and the connection lines CNL connected to each other. 
     The second power line PL 2  may be disposed in the non-display region NDA. The second power line PL 2  may extend along the long sides of the display panel DP and the other short side of the short sides of the display panel DP, near which the data driver DDV is not disposed. The second power line PL 2  may be disposed outside the scan driver SDV and the light emission driver EDV. 
     Although not illustrated, the second power line PL 2  may extend toward the display region DA so as to be connected to the pixels PX. A second voltage having a lower level than the first voltage may be applied to the pixels PX through the second power line PL 2 . 
     The first control line CSL 1  may be connected to the scan driver SDV and, in a plan view, extend toward the lower end of the display panel DP. The second control line CSL 2  may be connected to the light emission driver EDV and, in a plan view, extend toward the lower end of the display panel DP. The data driver DDV may be disposed between the first control line CSL 1  and the second control line CSL 2 . 
     The pads PD may be disposed on the display panel DP. The pads PD may be closer to the lower end of the display panel DP than the data driver DDV is to the lower end of display panel DP. The data driver DDV, the first power line PL 1 , the second power line PL 2 , the first control line CSL 1 , and the second control line CSL 2  may be connected to the pads PD. The data lines DL 1  to DLn may be connected to the data driver DDV, and the data driver DDV may be connected to the pads PD corresponding to the data lines DL 1  to DL 2 . 
     Although not illustrated, the display device DD may further include a timing controller for controlling the operation of the scan driver SDV, the data driver DDV, and the light emission driver EDV, and a voltage generator for generating first and second voltages. The timing controller and the voltage generator may be connected to corresponding pads PD through a printed circuit board. 
     The scan driver SDV may generate a plurality of scan signals, and the scan signals may be applied to the pixels PX through the scan lines SL 1  to SLm. The data driver DDV may generate a plurality of data voltages, and the data voltages may be applied to the pixels PX through the data lines DL 1  to DLn. The light emission driver EDV may generate a plurality of light emission signals and the light emission signals may be applied to the pixels PX through the light emission lines EL 1  to ELm. 
     The pixels PX may receive data voltages in response to scan signals. The pixels PX may display an image by emitting light having luminance corresponding to the data voltages in response to the light emission signals. A light emission time of the pixels PX may be controlled by the light emission signals. 
       FIG. 8  illustrates a folded state of the display device illustrated in  FIG. 5 . 
     In an embodiment, a display module DM is illustrated as a single layer in  FIG. 8 . 
     Referring to  FIG. 8 , the display device DD may be folded around the folding axis FX. The folding region FA is bent around the folding axis FX so that the display device DD may be folded. The folding portion FP is bent around the folding axis FX so that the support plate SPT may be folded. Since openings OP are defined in the folding portion FP, the support plate SPT may be easily folded. As a result, the display device DD may be more easily folded. 
       FIG. 9  is a plane view of the support plate illustrated in  FIG. 5 . 
     Referring to  FIG. 9 , the support plate SPT may have a quadrangular (e.g., rectangular) shape having long sides extending in the first direction DR 1  and short sides extending in the second direction DR 2 , but the shape of the support plate SPT is not limited thereto. 
     The support plate SPT may include a first non-folding portion NFP 1 , a second non-folding portion NFP 2 , and a folding portion FP disposed between the first and second non-folding portions NFP 1  and NFP 2 . The first non-folding portion NFP 1  may overlap the first non-folding region NFA 1 , the folding portion FP may overlap the folding region FA, and the second non-folding portion NFP 2  may overlap the second non-folding region NFA 2 . 
     The support plate SPT may include a plurality of first fibers FIB 1  and a plurality of second fibers FIB 2 . The first fibers FIB 1  and the second fibers FIB 2  may include carbon fibers. 
     In a plan view, the first fibers FIB 1  and the second fibers FIB 2  may extend to cross each other. In an embodiment, the first fibers FIB 1  may extend in a first diagonal direction DDR 1 , and the second fibers FIB 2  may extend in a second diagonal direction DDR 2 , for example. The first diagonal direction DDR 1  may be defined as a direction extending at an angle greater than or equal to 0 degree and less than 90 degrees with respect to the second direction DR 2  in a plan view defined by the first and second directions DR 1  and DR 2 . 
     The second diagonal direction DDR 2  may be defined as a direction crossing the first diagonal direction DDR 1  in a plan view defined by the first and second directions DR 1  and DR 2 . The second diagonal direction DDR 2  may be defined as a direction extending at an angle greater than or equal to 90 degrees and less than 180 degrees with respect to the second direction DR 2 . 
     The openings OP defined in the folding portion FP nay have a rhombic shape having sides extending in the first and second diagonal directions DDR 1  and DDR 2 . The openings OP may be arranged in the first diagonal direction DDR 1  and the second diagonal direction DDR 2  based on a position in which rhombus-shaped sides are disposed. In addition, the openings OP may be arranged in the first and second directions DR 1  and DR 2  based on a position in which rhombus-shaped vertices are disposed. 
       FIG. 10  is an enlarged view of the first region AA 1  illustrated in  FIG. 9 .  FIG. 11  is a cross-sectional view taken along line II-II′ illustrated in  FIG. 10 . 
     Referring to  FIGS. 10 and 11 , the support plate SPT may include a resin layer RSN and the first and second fibers FIB 1  and FIB 2  disposed inside the resin layer RSN. The resin layer RSN may include a plastic material. The first fibers FIB 1  and the second fibers FIB 2  may be disposed in different locations from each other in the third direction (also referred to as a thickness direction) DR 3 . In an embodiment, the second fibers FIB 2  may be disposed below the first fibers FIB 1 , for example. However, without being limited thereto, the second fibers FIB 2  may be disposed above the first fibers FIB 1 . 
     The first fibers FIB 1  may extend in the first diagonal direction DDR 1  and be arranged in the second diagonal direction DDR 2 . That is, the first fibers FIB 1  may extend at a first angle θ 1  greater than or equal to 0 degree and less than 90 degrees with respect to the second direction DR 2 . 
     The second fibers FIB 2  may extend in the second diagonal direction DDR 2  and be arranged in the first diagonal direction DDR 1 . That is, the second fibers FIB 2  may extend at a second angle θ 2  greater than or equal to 90 degrees and less than 180 degrees with respect to the second direction DR 2 . 
     When the first fibers FIB 1  extend at 0 degree with respect to the second direction DR 2  and the second fibers FIB 2  extend at 90 degrees with respect to the second direction DR 2 , the first fibers FIB 1  and the second fibers FIB 2  may cross each other perpendicularly. In this case, the first diagonal direction DDR 1  may be parallel to the second direction DR 2 , and the second diagonal direction DDR 2  may be parallel to the first direction DR 1 . 
     Although the first fibers FIB 1  extend at 0 degree with respect to the second direction DR 2 , the second fibers FIB 2  extend at an angle less than 180 degrees with respect to the second direction DR 2  and, therefore, the first fibers FIB 1  and the second fibers FIB 2  may extend so as not to be parallel to each other. 
     Although the second fibers FIB 2  extend at 90 degrees with respect to the second direction DR 2 , the first fibers FIB 1  extend at an angle less than 90 degrees with respect to the second direction DR 2  and, therefore, the second fibers FIB 2  and the first fibers FIB 1  may extend so as not to be parallel to each other. 
     The first fibers FIB 1  may extend at an angle greater than 0 degree and less than 90 degrees with respect to the second direction DR 2 , and the second fibers FIB 2  may extend at an angle greater than 90 degrees and less than 180 degrees with respect to the second direction DR 2 . In this case, the first diagonal direction DDR 1  may cross the first and second directions DR 1  and DR 2 . In addition, the second diagonal direction DDR 2  may cross the first and second directions DR 1  and DR 2 . 
       FIG. 12  is an enlarged view of the second region AA 2  illustrated in  FIG. 9 .  FIG. 13  is a cross-sectional view taken along line III-III′ illustrated in  FIG. 12 . 
     Referring to  FIGS. 12 and 13 , an opening OP may be defined by removing a predetermined portion of the support plate SPT. The opening OP may be defined by removing a portion of the resin layer RSN and portions of some of the first and second fibers FIB 1  and FIB 2 . 
     The opening OP may include first sides S 1  extending in parallel with the first fibers FIB 1  and facing each other, and second sides S 2  extending in parallel with the second fibers FIB 2  and facing each other. Two first sides S 1  may extend in the first diagonal direction DDR 1  and face each other in the second diagonal direction DDR 2 . Two second sides S 2  may extend in the second diagonal direction DDR 2  and face each other in the first diagonal direction DDR 1 . The second sides S 2  may be connected to ends of the first sides S 1 . 
     The opening OP may have a rhombic shape defined by the first d second sides S 1  and S 2  connected to each other. In an embodiment, the first fibers FIB 1  and the second fibers FIB 2  in  FIG. 12  may cross each other perpendicularly. That is, the first diagonal direction DDR 1  and the second diagonal direction DDR 2  may cross each other perpendicularly. 
     An inner angle of the rhombic shape of the opening OP may be 90 degrees. In this case, the distance between first vertices VT 1  opposite to each other n the first direction DR 1  may be the same as the distance between second vertices VT 2  opposite to each other in the second direction DR 2 . 
       FIG. 14  is an enlarged view of the third region AA 3  illustrated in  FIG. 9 . 
     Referring to  FIG. 14 , in the folding portion FP, the openings OP may be defined in some of the first and second fibers FIB 1  and FIB 2  and may not be defined in the other first and second fibers FIB 1  and FIB 2 . The openings OP may be partially defined in some of the first and second fibers FIB 1  and FIB 2 . 
     In the first fibers FIB 1  in which the openings OP are defined, the openings OP may be arranged along an extension direction of the first fibers FIB 1 . In the second fibers FIB 2  in which the openings OP are defined, the openings OP may be arranged along an extension direction of the second fibers FIB 2 . 
     Although two openings OP arranged in the first diagonal direction DDR 1  and two openings OP arranged in the second diagonal direction DDR 2  are illustrated, the number of the openings OP is not limited thereto. 
     In the folding portion FP, some first fibers NFIB 1  among the first fibers FIB 1  may pass between the openings OP and extend in the first diagonal direction DDR 1 . In the folding portion FP, some second fibers NFIB 2  among the second fibers FIB 2  may pass between the openings OP and extend in the second diagonal direction DDR 2 . 
     The first fibers NFIB 1  may be defined as the first fibers FIB 1  in which the openings OP are not defined. The second fibers NFIB 2  may be defined as the second fibers FIB 2  in which the openings OP are not defined. 
     Specifically, in the folding portion FP the first fibers NFIB 1  may pass between the openings OP arranged in the first direction DR 1  and extend in the first diagonal direction DDR 1 . In addition, in the folding portion FP, the first fibers NFIB 1  may pass between the openings OP arranged in the second direction DR 2  and extend in the first diagonal direction DDR 1 . 
     Specifically, in the folding portion FP, the second fibers NFIB 2  may pass between the openings OP arranged in the first direction DR 1  and extend in the second diagonal direction DDR 2 . In addition, in the folding portion FP, the second fibers NFIB 2  may pass between the openings OP arranged in the second direction DR 2  and extend in the second diagonal direction DDR 2 . 
     According to the above structures, the first and second fibers FIB 1  and FIB 2  in which the openings OP are defined and the first and second fibers NFIB 1  and NFIB 2  in which the openings OP are not defined may be disposed in the folding portion FP. 
       FIG. 15  illustrates a plane configuration of a support plate according to a comparative embodiment. 
     Referring to  FIG. 15 , the support plate SPT′ may include a plurality of first fibers FIB 1 ′ extending in the first direction DR 1  and a plurality of second fibers FIB 2 ′ extending in the second direction DR 2 . The first fibers FIB 1 ′ and the second fibers FIB 2 ′ may be disposed in different layers. 
     A plurality of openings OP′ may be defined in the folding portion FP of the support plate SPT′ overlapping the folding region FA. The openings OP′ may extend in the second direction DR 2 . The openings OP′ may be arranged in the first direction DR 1  and the second direction DR 2 . 
     The first direction DR 1  may correspond to a column direction, and the second direction DR 2  may correspond to a row direction. The openings OP′ arranged in the h-th row may be alternately arranged with the openings OP′ arranged in the h+1-th row. Here, h is a natural number. The openings OP′ arranged in the h-th row and the openings OP′ arranged in the h+1-th row may partially overlap each other when viewed from the first direction DR 1 . 
     Depending on the structures of the openings OP′, all of the first fibers FIB 1 ′ may be cut in the folding portion FP of the support plate SPT. Accordingly, when the folding portion FP is stretched, the restoring force of the folding portion FP to be restored may be reduced. In addition, as all of the first fibers FIB 1 ′ are cut in the folding portion FP, the lifespan of the support plate SPT′ may be reduced. 
     Although a state in which all of the first fibers FIB 1 ′ are cut in the folding portion FP is illustrated, when the first fibers FIB 1 ′ extend in the second direction DR 2  and the second fibers FIB 2 ′ extend in the first direction DR 1 , all of the second fibers FIB 2 ′ may be cut in the folding part FP by the openings OP. 
     Once again, referring to  FIGS. 9 and 14 , in an embodiment of the invention, depending on an arrangement structure of the openings OP, in the folding portion FP, the openings OP may be defined in some of the first and second fibers FIB 1  and FIB 2 , and the openings OP may not be defined in some of the first and second fibers NFIB 1  and NFIB 2 . Accordingly, cutting of the first and second fibers FIB 1  and FIB 2  in the folding portion FP may be minimized. As a result, the restoring force of the folding portion FP may not be reduced, and the lifespan of the support plate SPT may not be reduced. 
       FIGS. 16 to 18  illustrate configurations of openings according to various extension directions of the first and second fibers illustrated in  FIG. 9 . 
     In an embodiment,  FIGS. 16 to 18  are illustrated as enlarged views corresponding to  FIG. 12 , and hereinafter, mostly, configurations different from the configuration shown in  FIG. 12  will be described. 
     Referring to  FIG. 16 , an opening OP_ 1  defined in the folding region FA may have a rhombic shape extending longer in the second direction DR 2  than in the first direction DR 1 . The distance between the first vertices VT 1  opposite to each other in the first direction DR 1  may be different from the distance between the second vertices VT 2  opposite to each other in the second direction DR 2 . In an embodiment, the distance between the first vertices VT 1  may be shorter than the distance be tween the second vertices VT 2 , for example. 
     In order to form the structure of the opening OP_ 1  as described above, the first diagonal direction DDR 1  may extend at a first angle θ 1 _ 1  greater than 0 degree and less than 45 degrees with respect to the second direction DR 2 . In addition, the second diagonal direction DDR 2  may extend at a second angle θ 2 _ 1  greater than 135 degrees and less than 180 degrees with respect to the second direction DR 2 . 
     The first fibers FIB 1  may extend in the first diagonal direction DDR 1  at the first angle θ 1 _ 1  with respect to the second direction DR 2  and be arranged in the second diagonal direction DDR 2 . The second fibers FIB 2  may extend in the second diagonal direction DDR 2  at the second angle θ 2 _ 1  with respect to the second direction DR 2  and be arranged in the first diagonal direction DDR 1 . 
     The opening OP_ 1  may include first sides S 1 _ 1  extending in the first diagonal direction DDR 1  and facing each other in the second diagonal direction DDR 2  and second sides S 2 _ 1  extending in the second diagonal direction DDR 2  and facing each other in the first diagonal direction DDR 1 . 
     Referring to  FIG. 17 , an opening OP_ 2  defined in the folding region FA may have a rhombic shape extending longer in the second direction DR 2  than in the first direction DR 1 . The distance between the first vertices VT 1  opposite to each other in the first direction DR 1  may be different from the distance between the second vertices VT 2  opposite to each other in the second direction DR 2 . In an embodiment, the distance between the first vertices VT 1  may be longer than the distance between the second vertices VT 2 , for example. 
     In order to form the structure of the opening OP_ 2  as described above, the first diagonal direction DDR 1  may extend at a first angle θ 1 _ 2  greater than 45 degrees and less than 90 degrees with respect to the second direction DR 2 . In addition, the second diagonal direction DDR 2  may extend at a second angle θ 2 _ 2  greater than 90 degrees and less than 135 degrees with respect to the second direction DR 2 . 
     The first fibers FIB 1  may extend in the first diagonal direction DDR 1  at the first angle θ 1 _ 2  with respect to the second direction DR 2  and be arranged in the second diagonal direction DDR 2 . The second fibers FIB 2  may extend in the second diagonal direction DDR 2  at the second angle θ 2 _ 2  with respect to the second direction DR 2  and be arranged in the first diagonal direction DDR 1 . 
     The opening OP_ 2  may include first sides S 1 _ 2  extending in the first diagonal direction DDR 1  and facing each other in the second diagonal direction DDR 2  and second sides S 2 _ 2  extending in the second diagonal direction DDR 2  and facing each other in the first diagonal direction DDR 1 . 
     Referring to  FIG. 18 , an opening OP_ 3  defined in the folding region FA may have a tetragonal shape. In order to form the structure of the opening OP_ 3  as described above, the first diagonal direction DDR 1  may extend in the second direction DR 2 , and the second diagonal direction DDR 2  may extend in the first direction DR 1 . 
     The first fibers FIB 1  may extend in the first direction DR 1  and be arranged in the second direction DR 2 . The second fibers FIB 2  may extend in the second direction DR 2  and be arranged in the first direction DR 1 . 
     The opening OP_ 3  may include first sides S 1 _ 3  extending in the first direction DR 1  and facing each other in the second direction DR 2  and second sides S 2 _ 3  extending in the second direction DR 2  and facing each other in the first direction DR 1 . 
       FIGS. 19 and 20  illustrate various shapes of the openings illustrated in  FIG. 9 . 
     In an embodiment,  FIGS. 19 and 20  are illustrated as enlarged views corresponding to  FIG. 12 , and hereinafter, mostly, configurations different from the configuration shown in  FIG. 12  will be described. 
     Referring to  FIGS. 19 and 20 , the extension directions of first and second fibers FIB 1  and FIB 2  may be the same as the extension directions of the first and second fibers FIB 1  and FIB 2  illustrated in  FIG. 12 . Openings OP_ 4  and OP_ 5  may extend longer n any one direction among an extension direction of the first fibers FIB 1  and an extension direction of the second fibers FIB 2 . 
     Referring to  FIG. 19 , the opening OP_ 4  having a rhombic shape may extend longer in the first diagonal direction DDR 1  than in the second diagonal direction DDR 2 . The opening OP_ 4  may include first sides S 1 _ 4  extending in the first diagonal direction DDR 1  and facing each other in the second diagonal direction DDR 2  and second sides S 2 _ 4  extending in the second diagonal direction DDR 2  and facing each other in the first diagonal direction DDR 1 . The length of the first sides S 1 _ 4  may be greater than that of the second sides S 2 _ 4 . 
     Referring to  FIG. 20 , the opening OP_ 5  having a rhombic shape may extend longer in the second diagonal direction DDR 2  than in the first diagonal direction DDR 1 . The opening OP_ 5  may include first sides S 1 _ 5  extending in the first diagonal direction DDR 1  and facing each other in the second diagonal direction DDR 2  and second sides S 2 _ 5  extending in the second diagonal direction DDR 2  and facing each other in the first diagonal direction DDR 1 . The length of the first sides S 1 _ 5  may be smaller than that of the second sides S 2 _ 5 . 
     By the embodiments of the invention, the display device may be lightened by the support plate including CFRP to support the display module. 
     In addition, the display device may be easily folded as a plurality of openings are defined in a portion of the support plate overlapping the folding region. 
     Furthermore, in the folding portion of the support plate, openings are defined in some of the first and second fibers, and openings e not defined in the other first and second fibers. Therefore, cutting of the first and second fibers in the folding portion may be minimized. 
     Although the embodiments of the invention have been described, it is understood that the invention should not be limited to these embodiments but various changes and modifications may be made by one ordinary skilled in the art within the spirit and scope of the invention as hereinafter claimed.