KR20190003257A - Foldable display device - Google Patents

Abstract

According to the present invention, disclosed is a foldable display device capable of increasing screen unevenness in a folding region. The foldable display device comprises: a display panel having two or more flat regions and a folding region between the flat regions; and a support member with a multilayer structure positioned on one surface of the display panel and supporting the display panel. The support member has an opening pattern in a region corresponding to the folding region.

Description

FOLDABLE DISPLAY DEVICE}

The present disclosure relates to a folderable display device.

The image display device that realizes various information on the screen is a core technology of the information communication age and it is becoming thinner, lighter, more portable and higher performance. Accordingly, an organic light emitting display device for displaying an image by controlling the amount of light emitted from the organic light emitting device has attracted attention.

The organic light emitting device is advantageous in that it can be made thin as a self-luminous device using a thin light emitting layer between electrodes. A general organic light emitting display has a structure in which a pixel driving circuit and an organic light emitting element are formed on a substrate, and light emitted from the organic light emitting element passes through a substrate or a barrier layer to display an image.

Since the organic light emitting display device is implemented without a separate light source device, it is easy to be implemented as a flexible, bendable, or foldable display device. At this time, a flexible material such as plastic, metal foil or the like is used as a substrate of the organic light emitting display device. In addition, flexible, foldable display devices and the like generally have a plurality of thin film layers stacked on a substrate.

For example, a foldable display may be composed of a series of adhesive layers for various functional films and their lamination. The foldable display device needs to be restored to its initial state after being folded and flattened. However, currently used materials have a limitation in complete restoration, and their stability is lowered even in a high temperature / high humidity environment. Therefore, in order to improve the usability of the display device of the present invention, material or structural improvement is demanded for ensuring flexibility and stability.

It is an object of the present invention to propose a foldable display device and a folding structure used therefor. The problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to one embodiment of the present disclosure, a display device is provided. The display device comprising: a display panel having two or more flat regions and a folding region between the flat regions; And a support member positioned on one side of the display panel and supporting the display panel, wherein the support member has an opening pattern in an area corresponding to the folded area. .

Wherein the support member comprises: a first metal layer underlying the display panel; And a second metal layer below the first metal layer and having an opening pattern in an area corresponding to the folded area, wherein the first metal layer may have no opening pattern in an area corresponding to the folded area .

The second metal layer may be thicker than the first metal layer.

The support member may further include a third metal layer below the second metal layer and having an opening pattern in an area corresponding to the folded area.

The third metal layer may be thicker than the second metal layer.

The third metal layer may have an opening pattern wider than the second metal layer.

The first metal layer can reduce the screen unevenness due to the opening pattern in the second metal layer or the third metal layer.

The opening pattern may be a slit having a shape extending in a direction parallel to the folding axis.

The opening pattern may have a shape of at least one of a rectangle, a rhombus, an ellipse, and a rectangle having rounded corners.

At least a portion of the opening pattern may be filled with silicon.

And an adhesive layer between the display panel and the support member.

The second metal layer or the third metal layer may have an opening pattern in a region corresponding to the flat region.

The details of other embodiments are included in the detailed description and drawings.

Embodiments of the present disclosure can provide a supporting structure suitable for the dynamic behavior of the display device. Furthermore, embodiments of the present disclosure can provide an adhesive member for enhancing the folding property and the restoring force of the foldable display device. Furthermore, the above-described display device can improve the unevenness of the screen in the folded area. The effects according to the embodiments of the present invention are not limited by the contents exemplified above, and more various effects are included in the specification.

Fig. 1 shows an exemplary folderable display device.
2 is a sectional view showing a part of a display panel included in the display device of the present specification.
FIGS. 3A and 3B are views for explaining a display device according to an embodiment of the present invention.
4A to 4C are cross-sectional views illustrating a display device according to an embodiment of the present invention.
5A to 5D are views for explaining the shape of the opening pattern applied to the support member according to the embodiment of the present invention.
6A to 6D are views for explaining the arrangement of the opening pattern applied to the support member according to the embodiment of the present invention.

Brief Description of the Drawings The advantages and features of the present disclosure, and how to accomplish them, will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers and the like disclosed in the drawings for describing the embodiments of the present invention are illustrative, and thus the present invention is not limited thereto. Like reference numerals refer to like elements throughout the specification. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Where the terms "comprises", "having", "done", and the like are used in this specification, other portions may be added unless "only" is used. Unless the context clearly dictates otherwise, including the plural unless the context clearly dictates otherwise. In interpreting the constituent elements, it is construed to include the error range even if there is no separate description.

In the case of a description of the positional relationship, for example, if the positional relationship between two parts is described as 'on', 'on top', 'under', and 'next to' Or " direct " is not used, one or more other portions may be located between the two portions. An element or layer is referred to as being another element or layer "on ", including both intervening layers or other elements directly on or in between. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, Quot; intervening "or that each component may be" connected, "" coupled, "or " connected" through other components.

Although the first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, the first component mentioned below may be the second component within the technical spirit of the present invention.

The sizes and thicknesses of the individual components shown in the figures are shown for convenience of explanation and the present invention is not necessarily limited to the size and thickness of the components shown. Various embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

Fig. 1 shows an exemplary folderable display device.

The foldable display device 1000 may include at least one active area. For example, the display device of the present invention may have a plurality of display areas divided into right and left (or up and down) on the basis of a folding line. An array of pixels is formed in the display area. One or more inactive areas may be disposed around the display area. That is, the non-display area may be adjacent to one or more sides of the display area. In Fig. 1, the non-display area surrounds a display area of a rectangular shape. However, the shape of the display region and the shape / arrangement of the non-display region adjacent to the display region are not limited to the example shown in Fig. The display area and the non-display area may be in a form suitable for the design of the electronic device on which the display device 1000 is mounted. Illustrative forms of the display area are pentagonal, hexagonal, circular, oval, and the like.

Each pixel in the display area may be associated with a pixel circuit. The pixel circuit may include one or more switching transistors and one or more driving transistors on a backplane. Each pixel circuit may be electrically connected to a gate line and a data line to communicate with one or more driving circuits such as a gate driver and a data driver located in the non-display area.

The driving circuit may be implemented with a thin film transistor (TFT) in the non-display region, as shown in FIG. This driving circuit may be referred to as a gate-in-panel (GIP). In addition, some components, such as a data driver IC, are mounted on a separate printed circuit board, and circuit films such as flexible printed circuit boards (FPCB), chip-on-film (COF), tape- (Pad / bump, pin, etc.) disposed in the non-display area.

The display device 1000 may include various additional elements for generating various signals or driving pixels in the display area. An additional element for driving the pixel may include an inverter circuit, a multiplexer, an electrostatic discharge circuit, and the like. The display device 1000 may also include additional elements associated with functions other than pixel driving. For example, the display apparatus 1000 may include additional elements for providing a touch sensing function, a user authentication function (e.g., fingerprint recognition), a multi-level pressure sensing function, a tactile feedback function, and the like. The above-mentioned additional elements may be located in the non-display area and / or an external circuit connected to the connection interface.

Various parts of the display device 1000 can be bent along the curved line FL. The curved line FL may extend horizontally (e.g., in the X direction in FIG. 1), vertically (e.g., in the Y direction in FIG. 1), or diagonally. Based on the design, it can be bent in a combination of horizontal, vertical, and diagonal directions.

As mentioned, one or more edges of the display device 1000 may be bent away from the central portion 1000-1 along the curved line FL. Although the curved line FL is shown to be positioned close to the edge of the display device 1000, the curved line FL may extend across the central portion 1000-1, And may extend diagonally at one or more corners of the frame.

In some embodiments, the curved portion 1000-2 of the display device 100 may include a display area capable of displaying an image. Such a display area is hereinafter referred to as an auxiliary display area. That is, the curved line FL can be placed in the display area so that at least some pixels of the display area are included in the curved part 1000-2.

2 is a sectional view showing a part of a display panel included in the display device of the present specification.

The display device 1000 can be composed of a display panel 100 for displaying an image and various mechanical parts (frame, case, etc.). Hereinafter, an organic light emitting display panel A folder-type display apparatus and its display panel will be described.

In the organic light emitting display panel 100, thin film transistors 102, 104, 106 and 108, organic light emitting devices 112, 114 and 116 and various functional layers are disposed on a base layer 101.

The base layer 101 supports various components of the organic light emitting display panel 100. The base layer 101 may be formed of a transparent insulating material, for example, an insulating material such as glass, plastic, or the like. When the base layer 101 is made of plastic, it may be referred to as a plastic film or a plastic substrate. For example, the base layer 101 may be in the form of a film including one selected from the group consisting of a polyimide-based polymer, a polyester-based polymer, a silicone-based polymer, an acrylic polymer, a polyolefin-based polymer, and copolymers thereof. Of these materials, polyimide can be applied to a high-temperature process and is widely used as a plastic substrate because it is a material that can be coated. The substrate (array substrate) may be referred to as a concept including an element and a functional layer formed on the base layer 101, for example, a switching TFT, a driving TFT connected to the switching TFT, an organic light emitting element connected to the driving TFT, do.

A buffer layer may be located on the base layer 101. The buffer layer is a functional layer for protecting a thin film transistor (TFT) from an impurity such as alkali ions or the like, which flows out from the base layer 101 or the lower layers. The buffer layer may be formed of silicon oxide (SiOx), silicon nitride (SiNx), or a multilayer thereof.

A thin film transistor is placed on the base layer 101 or the buffer layer. The thin film transistor may have a configuration in which a semiconductor layer 102, a gate insulating film 103, a gate electrode 104, an interlayer insulating film 105, and source and drain electrodes 106 and 108 are sequentially arranged. The semiconductor layer 102 is located on the base layer 101 or the buffer layer. The semiconductor layer 102 may be made of polysilicon (p-Si), in which case a predetermined region may be doped with an impurity. Further, the semiconductor layer 102 may be made of amorphous silicon (a-Si), or may be made of various organic semiconductor materials such as pentacene. Further, the semiconductor layer 102 may be made of oxide. The gate insulating film 103 may be formed of an insulating inorganic material such as silicon oxide (SiOx) or silicon nitride (SiNx), or may be formed of an insulating organic material or the like. The gate electrode 104 may be formed of various conductive materials such as Mg, Al, Ni, Cr, Mo, W, Au, Or the like.

The interlayer insulating film 105 may be formed of an insulating material such as silicon oxide (SiOx) or silicon nitride (SiNx), or may be formed of an insulating organic material or the like. A contact hole through which the source and drain regions are exposed may be formed by selective removal of the interlayer insulating film 105 and the gate insulating film 103.

The source and drain electrodes 106 and 108 are formed on the interlayer insulating film 105 in the form of a single layer or a multi-layered structure as an electrode material.

The planarizing layer 107 may be located on the thin film transistor. The planarizing layer 107 protects the thin film transistor and flattenes the top surface thereof. The planarization layer 107 may be formed in various shapes and may be formed of an organic insulating film such as BCB (benzocyclobutene) or acrylic or an inorganic insulating film such as a silicon nitride film (SiNx) or a silicon oxide film (SiOx) It may be formed as a single layer, or it may be composed of a double layer or a multi layer.

The organic light emitting device may have a structure in which a first electrode 112, an organic light emitting layer 114, and a second electrode 116 are sequentially arranged. That is, the organic light emitting device includes a first electrode 112 formed on the planarization layer 107, an organic light emitting layer 114 disposed on the first electrode 112, and a second electrode (not shown) disposed on the organic light emitting layer 114 116).

The first electrode 112 is electrically connected to the drain electrode 108 of the driving thin film transistor through the contact hole. When the organic light emitting display panel 100 is a top emission type, the first electrode 112 may be made of an opaque conductive material having a high reflectivity. For example, the first electrode 112 may be formed of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr) .

The bank 110 is formed in the remaining region except for the light emitting region. Accordingly, the bank 110 has a bank hole for exposing the first electrode 112 corresponding to the light emitting region. The bank 110 may be made of an inorganic insulating material such as a silicon nitride film (SiNx), a silicon oxide film (SiOx), or an organic insulating material such as BCB, acrylic resin or imide resin.

The organic light emitting layer 114 is positioned on the first electrode 112 exposed by the bank 110. [ The organic light emitting layer 114 may include a light emitting layer, an electron injection layer, an electron transport layer, a hole transport layer, a hole injection layer, and the like. The organic light emitting layer may have a single light emitting layer structure that emits a single light or may include a plurality of light emitting layers to emit white light.

And the second electrode 116 is located on the organic light emitting layer 114. When the organic light emitting display panel 100 is a top emission type, the second electrode 116 is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO) Thereby emitting the light generated in the organic light emitting layer 114 to the upper portion of the second electrode 116.

The protective layer 118 and the encapsulation layer 120 are located on the second electrode 116. The protective layer 118 and the sealing layer 120 prevent oxygen and moisture penetration from the outside in order to prevent oxidation of the light emitting material and the electrode material. When the organic light emitting device is exposed to moisture or oxygen, a pixel shrinkage phenomenon in which the light emitting region is reduced or a dark spot in the light emitting region may occur. The passivation layer and / or the encapsulation layer may be composed of an inorganic film made of glass, metal, aluminum oxide (AlOx), or silicon (Si) material, or alternatively, It may be a laminated structure. The inorganic film serves to block penetration of moisture or oxygen, and the organic film serves to flatten the surface of the inorganic film. The reason why the encapsulation layer is formed of a plurality of thin film layers is to make the movement path of water or oxygen longer and more complicated than in the case of a single layer so as to make penetration of moisture / oxygen into the organic light emitting element difficult.

The organic light emitting display panel 100 may include a touch panel 150 for sensing a user's touch input on the sealing layer 120. If desired, a separate layer may be provided within the display panel 100 with touch sensing electrodes and / or other components associated with touch input sensing. The touch sensing electrode (e.g., the touch driving / sensing electrode) may be formed of a conductive material such as indium tin oxide, a carbon based material such as graphene, a carbon nanotube, a conductive polymer, or a hybrid material made of a mixture of various conductive / non- May be formed of a transparent conductive material. In addition, a metal mesh such as an aluminum mesh or a silver mesh may be used as the touch sensing electrode.

The cover layer 180 may be used to protect the upper portion of the display panel 100. The cover layer 140 may be a cover glass. A polarizing layer for controlling display characteristics (e.g., external light reflection, color accuracy, brightness, and the like) may be disposed on one side of the cover layer 180. In one embodiment, The polarizing layer 170 can be coated.

At least one reinforcing film may be provided under the base layer 101 to increase the strength and / or firmness at a particular portion of the display device 1000. The reinforcing film is attached to the opposite surface (second surface) of the surface (first surface) on which the organic light emitting element is present on both surfaces of the base layer 101. The reinforcing film may be formed of a material selected from the group consisting of polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyethylene ether phthalate, polycarbonate, polyarylate, polyetherimide polyether imide, polyether sulfonate, polyimide polyacrylate, or any other suitable polymer. Another material that can be used in forming the reinforcing film may be a thin film glass, a multilayer polymer, a polymer film containing a polymer material in combination with nanoparticles or microparticles, and the like.

FIGS. 3A and 3B are views for explaining a display device according to an embodiment of the present invention.

The foldable display device may be composed of a plurality of thin film layers and an adhesive for bonding them. Due to the material characteristics and limitations, the foldable display device may have a flatness in a folded curvature, a repeated folding and / Maintenance is important.

The foldable display device may include two or more flat areas A-1 and A-2 and a folded area F between the flat areas A-1 and A-2, And can be folded as shown in FIG. 3B. The flat areas A-1 and A-2 are substantially flat areas (parts) having a very small curvature as compared with the folding area F, and may include a display area, / RTI > In FIG. 3A, only two flat areas are shown, but actual implementations may be composed of two or more flat areas. A folding area (center bezel) Since the width of the gap is correlated with the folding radius, it can be determined on the basis of this, and it is desirable to design in consideration of the encapsulation margin. The folded region F may be understood as the sum of the actual folded portion and the encapsulation margin.

The pixel matrix in the second flat area A-2 can be continuously extended from the first flat area A-1. Alternatively, in Fig. 3A, the first flat region and the second flat region may be separated from each other with a folded region in between. Some parts of the first flat area and the second flat area may be electrically connected through one or more leads laid across the folded area. The pixels of the first flat area A-1 and the pixels of the second flat area A-2 can be driven as if they are in the same matrix by a driving circuit (e.g., gate driver, data driver, etc.). At this time, the pixels of the first flat area A-1 and the pixels of the second flat area A-2 can be operated by the same driving circuits. For example, the Nth row pixel of the first flat area A-1 and the Nth row pixel of the second flat area A-2 may be provided to receive the gate signal from the same gate driver. Depending on the implementation, the pixels of the second flat area A-2 may be driven separately from the pixels of the first flat area A-1. That is, the pixels of the second flat area A-2 can be recognized by the driving circuit as an independent matrix separated from the pixel matrix of the flat area. In this case, the pixels of the second flat area A-2 can receive signals from one or more separate driving circuits that are different from the driving circuits that supply signals to the pixels of the first flat area A-1 . On the other hand, the second flat region A-2 can function as the secondary display region of the display panel 100 regardless of its shape. The size ratio of the first flat region A-1 to the second flat region A-2 is not particularly limited.

3B, it is important that the support member 300 is designed so that the display panel 100 is not subjected to excessive compressive force or tensile force. In the foldable display device 1000 shown in FIG. In addition, the shape and material of the support member 300 are also very important for maintaining the flatness of the display device 1000 and / or for restoring the shape quickly. FIG. 3B shows an inward foldable display device, but the same importance is also applied to an outward foldable display device which is folded in the opposite direction.

4A to 4C are cross-sectional views illustrating a display device according to an embodiment of the present invention.

4A, the display panel 100 and the support member 300 may be bonded to each other. The foldable display device 1000 includes at least two flat areas and a folded area F between the flat areas, and the folded area F has a structure having improved foldability and restoring force . 2, the display panel 100 includes a flexible base layer 101, a structure in which an organic light emitting device layer (TFT / OLED), a touch panel 150, a polarizing layer 170, a cover layer 180, And a supporting member 300 may be further disposed under the display panel 100. [ An adhesive layer and / or the reinforcing film may be further disposed between the display panel 100 and the supporting member.

Since the folded region F is most affected by the bending stress, various stress reduction structures can be applied to the display panel 100 on the folded region. To this end, some of the components in the flat region may not be present in at least a portion of the folded region (F). For example, organic light emitting devices (e.g., pixel circuits and organic light emitting diodes) may not be disposed in the folded region F. Also, only a minimum number of layers may be disposed in the folded region F. For example, only the base layer, the organic material layer on the base layer, and the cover layer on the organic material layer may be disposed in the folded region F. [ The folded region F may further include a base layer and a patterned inorganic layer between the organic layers. The inorganic layer may be a buffer layer. The patterning may be implemented through a series of etching processes. The pattern may be in the form of a stripe parallel to the folding axis, and the pitch may be designed in consideration of the folding curvature.

The support member 300 is positioned on one surface (lower surface) of the display panel 100. For example, as shown in FIG. 4B, the support member 300 may cover the outer surface of the display panel 100 at the rear side of the screen display direction. The supporting member 300 serves to support the display panel 100. Therefore, the support member 300 has greater stiffness than the display panel.

When the foldable display apparatus 1000 is folded and unfolded repeatedly, plastic deformation is generated in the support member 300, so that folding / spreading of the foldable display apparatus 10 may be limited. The plastic deformation problem can be reduced by reducing the thickness of the support member 300. However, if the thickness of the support member 300 is reduced, the elastic restoring energy is also reduced and the tradeoff trade-off.

Thus, the inventors devised a support member that is thin and has sufficient rigidity to support the display panel, but has excellent restoring force after deformation. The support member 300 according to one embodiment of the present invention may be a multi-layer structure composed of two or more metal layers.

As shown in FIG. 4B, the support member 300 may have a high restoring force including two or more metal layers having a large stiffness and / or a Young's modulus. The metal layers 310, 320, 330, and 340 have a folded region F between the flat regions, as in the region classification of the display device 1000 of the present invention. At least one of the metal layers 310, 320, 330, and 340 may have opening patterns 321, 331, and 341 in the folded region F. Furthermore, the support member 300 may include a structure capable of preventing deterioration of image quality due to the opening patterns 321, 331, and 341.

The metal layers 310, 320, 330, and 340 included in the support member 300 may all be metal layers of the same kind of material. In some embodiments, the metal layers 310 may be different kinds of metal layers. The metal layers 310, 320, 330, and 340 may all have a yield stress of greater than 1 GPa.

When an object receives a force from the outside, the strain and stress increase in proportion to the force up to a certain point. On the other hand, when the force is removed, the strain and stress linearly decrease and return to the initial shape before deformation. However, if the magnitude of the force exceeds a certain value, the object can not be restored to the initial shape even if the force is removed, and the permanent deformation is maintained to some extent. From this point onward, strain and stress no longer maintain a linear relationship but also exhibit rapid strain and ultimate failure. Yield stress refers to the stress value that serves as a reference for distinguishing such apparent object behavior. That is, under the yield stress, the strain and the stress maintain a linear relationship, and when the force is removed, no permanent deformation remains. However, in the case of the force above the yield stress, the strain and the stress exhibit a remarkable nonlinear relationship, and even if the force is removed, the object exhibits a permanent deformation.

4B and 4C, the first metal layer 310, the second metal layer 320, the third metal layer 320, the third metal layer 320, Layer 330, and fourth metal layer 340, respectively. 4B and 4C, the second metal layer 320, the third metal layer 330 and the fourth metal layer 340 include opening patterns 321, 331 and 341 in the folded region F .

The opening patterns 321, 331, and 341 included in the second to fourth metal layers 320, 330, and 340 reduce stress when the supporting member 300 is folded. The shape and arrangement of the opening pattern in each metal layer will be described in more detail in Figs. 5-6. The opening patterns 321, 331, and 341 may be slits of various shapes such as a rectangle, a rhombus, and an ellipse, and the widths w2, w3, and w4 may become wider downward. (w2 < w3 < w4), that is, a metal layer far from the display panel has a wide opening pattern.

At least one of the metal layers included in the support member 300 has no opening pattern. 4B and 4C, the first metal layer 310 has no opening pattern. The reason why the support member 300 includes the metal layer having no opening pattern is to uniform the brightness of the display panel. As a result of the test, unevenness of brightness such as stain appeared in the folded area when the folder display device was unfolded, which was analyzed as the main cause of temperature unevenness due to the opening pattern in the folded area. It is also confirmed that the above-described unevenness can be prevented by placing a metal layer without an opening pattern between the display panel 100 and the metal layer having the opening pattern. Accordingly, the support member 300 according to the embodiment of the present invention disposes at least one metal layer 310 having no opening pattern nearest the display panel 100. That is, at least one metal layer having no opening pattern is located between the display panel 100 and the metal layer having the opening pattern.

Meanwhile, the metal layers 310, 320, 330, and 340 included in the support member 300 may have different thicknesses. The thicknesses t1, t2, t3, and t4 may become thicker . (t1 <t2 <t3 <t4), that is, the metal layer far from the display panel 100 may be thicker. In FIG. 4B, the thickness t1 of the first metal layer 310 is the thinnest, and the thickness t4 of the fourth metal layer 340 is the thickest.

The opening pattern is formed in the folded region (F). However, according to the embodiment, the opening pattern may be provided outside the folded area, i.e., in the flat area.

At least a part of the opening patterns 321, 331 and 341 may be filled with at least one of polyurethane (PU), thermoplastic polyurethane (TPU), polyacrylate, rubber, and silicon (Si).

5A to 5D are views for explaining the shape of the opening pattern applied to the support member according to the embodiment of the present invention.

The opening pattern is provided for improving the folding and restoring property of the metal layer constituting the supporting member. The opening pattern is formed in the folded region (F). However, according to the embodiment, the opening pattern may be provided outside the folded area, i.e., in the flat area.

5A to 5D, only the second metal layer 320 and the opening pattern 321 therein are shown for the sake of convenience. However, the opening pattern 321 may include the third metal layer 330 and the fourth metal layer 340 ). 5A to 5D, the folded region F is shown as being located at a specific portion of the metal layer 320, but the position of the folded region F is not limited thereto. Further, two or more of the folded regions F may be defined.

As shown in FIG. 5A, the opening pattern 321a may have a rectangular shape. At this time, the opening pattern 321a may extend in a direction parallel to the folding line (folding axis). That is, the long axis of the opening pattern 321a may be parallel to the folding line (folding axis) and direction. The rectangular shape may have a specific length L1 and may be spaced apart by a specific distance D1 on the same line.

Further, as shown in Figs. 5B and 5C, each of the opening patterns 321b may have a rhombic shape. At this time, the opening patterns 321b and 321c may extend in a direction parallel to the folding line (folding axis). That is, the long axis of the opening patterns 321b and 321c may be parallel to the folding line (folding axis) and direction. The diamond shape may have a specific length (L2, L3) and may be spaced apart by a specific distance (D2, D3) on the same line. On the other hand, the rhombic shapes arranged in the same column may be placed side by side (Fig. 5B) or shifted (Fig. 5C) from the rhombic patterns arranged in adjacent rows.

As shown in FIG. 5D, the opening pattern 321d may have an elliptical shape having a constant minor axis length, or a semi-circular shape coupled to both ends of a rectangle. At this time, the opening pattern 321d may extend in a direction parallel to the folding line (folding axis). That is, the long axis of the opening pattern 321d may be parallel to the folding line (folding axis) and direction. The ellipse (or rounded rectangle) shape may have a specific length L4 and may be spaced apart by a specific distance D4 on the same line.

5A to 5D, the opening patterns 321a, 321b, 321c, and 321d are rectangular, rhombic, or elliptical, but the shape of the opening pattern is not limited thereto. For example, the opening pattern may have a different shape such as a circular shape, an elliptical shape, a square shape, and a trapezoidal shape. Also, it is not possible to form only one opening pattern shape in one metal layer. In other words, opening patterns of various shapes may be provided in one metal layer.

6A to 6D are views for explaining the arrangement of the opening pattern applied to the support member according to the embodiment of the present invention.

6A to 6D illustrate only the second metal layer 320 and the opening pattern 321 in the metal layers included in the supporting member for the convenience of explanation, 330 and the fourth metal layer 340. [0050] 6A to 6D, the folded region F is shown as being located at a specific portion of the metal layer 320, but the position of the folded region F is not limited thereto.

6A and 6B, a folding region F is defined in the metal layer 320 and the folding region F can be divided into a center portion CN and edge portions ED1 and ED2. At this time, the opening patterns 321 formed in the folded region F have the same size and different distances therebetween. (pitch variable)

The folded region F is divided into a center portion CN, a first edge portion ED1 and a second edge portion ED2, and the opening pattern 321 is separated from the first edge portion ED1 in the folding direction by a first distance And a third spacing distance d3 that is greater than the second spacing distance and less than the first spacing distance at the second edge portion ED2 with a distance d1 and a second spacing distance d2 at the center portion CN. That is, the distance between the opening pattern 321 and the center of the folded area F can be reduced. Stress may be concentrated on the first edge portion ED1 at the point where the curvature of the display device of the display unit of the foldable display starts, and damage of the display panel may occur. In the support member in this specification, the folding region F The radius of curvature at the starting point of the folding can be increased and stress concentration can be alleviated. Thus, damage to the display panel is minimized or prevented.

6C and 6D, a folding region F is defined in the metal layer 320 and the folding region F can be divided into a center portion CN and edge portions ED1 and ED2. At this time, the opening patterns 321 formed in the folded region F are arranged at the same distance and have different sizes. (size variable)

The opening pattern 321 is divided into a first edge portion ED1 and a second edge portion ED2 in the folding direction. The folded region F is divided into a center portion CN, a first edge portion ED1, and a second edge portion ED2. and has a second width w2 at the center portion CN and a third width w3 at the second edge portion ED2 that is greater than the first width and less than the second width. That is, the size (width) of the opening pattern 321 may gradually increase from the edge of the folded region F toward the center. The size of the opening pattern 321 formed in the folding region F of the metal layer 320 in the support member of the present specification is adjusted so that the radius of curvature at the folding start point is increased and stress concentration is alleviated. Thus, damage to the display panel is minimized or prevented.

The arrangement variation and the size variation of the opening pattern illustrated in Figs. 6A and 6B and 6C and 6D may be applied together in one metal layer.

While the embodiments of the present invention have been described in detail with reference to the accompanying drawings, it is to be understood that the present invention is not limited to these embodiments, and various modifications may be made without departing from the scope of the present invention. Therefore, the embodiments disclosed herein are for the purpose of describing rather than limiting the technical spirit of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other, partially or wholly, and may be technically variously interlocked and driven by one of ordinary skill in the art and that each embodiment may be implemented independently of one another, . The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (12)

A display panel having two or more flat regions and a folding region between the flat regions; And
And a support member disposed on one side of the display panel and having a multi-layer structure for supporting the display panel,
Wherein the support member has an opening pattern in an area corresponding to the folded area. The method according to claim 1,
Wherein the support member comprises:
A first metal layer underlying the display panel; And
And a second metal layer below the first metal layer and having an opening pattern in an area corresponding to the folded area,
Wherein the first metal layer has no opening pattern in a region corresponding to the folded region. 3. The method of claim 2,
Wherein the second metal layer is thicker than the first metal layer. 3. The method of claim 2,
Wherein the support member comprises:
And a third metal layer below the second metal layer and having an opening pattern in an area corresponding to the folded area. 5. The method of claim 4,
Wherein the third metal layer is thicker than the second metal layer. 5. The method of claim 4,
Wherein the third metal layer has an opening pattern wider than the second metal layer. The method according to claim 2 or 4,
Wherein the first metal layer reduces a screen unevenness due to an opening pattern in the second metal layer or the third metal layer. The method according to claim 1,
Wherein the opening pattern is a slit having a shape extending in a direction parallel to the folding axis. 9. The method of claim 8,
Wherein the opening pattern has at least one shape of a rectangle, a rhombus, an ellipse, and a rectangle having rounded corners. The method according to claim 1,
Wherein at least a part of the opening pattern is filled with silicon. The method according to claim 1,
And an adhesive layer between the display panel and the support member. The method according to claim 2 or 4,
Wherein the second metal layer or the third metal layer has an opening pattern in a region corresponding to the flat region.

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