Display device

Abstract

The present invention provides a display device. According to one aspect of the present disclosure, the display device includes: a display unit; and a roller configured so that the display unit is rolled around the roller or unfolded from the roller, the roller including a flat portion, a first curved portion extending from the flat portion, and a second curved portion extending from the first curved portion toward the flat portion, wherein the radius of curvature of the first curved portion is greater than the radius of curvature of the second curved portion, and the radius of curvature of the display unit rolled around the second curved portion is greater than the radius of curvature of the second curved portion. Therefore, the second curved portion is formed to support the display unit so that the display unit does not bend with a small radius of curvature between the first curved portion and the flat portion.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the priority of Korean Patent Application No. 10-2021-0123140 filed in the Korean Intellectual Property Office on September 15, 2021, the disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to a display device, and more particularly, to a rollable display device capable of displaying an image even when the display device is rolled up. Background Art

[0004] As display devices used for displays of computers, televisions, mobile phones, and the like, there are organic light emitting displays (OLEDs) configured to emit light autonomously and liquid crystal displays (LCDs) requiring a separate light source.

[0005] The application range of the display device is diverse from monitors of computers and televisions to personal mobile devices, and research on a display device having a wide display area and having reduced volume and weight is being conducted.

[0006] In addition, recently, a rollable display device has attracted attention as a next-generation display device, which is made by forming a display element, a circuit, etc. on a substrate made of a flexible plastic material having flexibility and thus can display an image even when the rollable display device is rolled up. Summary of the invention

[0007] An object to be achieved by the present disclosure is to provide a display device in which damage to the display device caused by repeated winding and unwinding processes is minimized.

[0008] Another object to be achieved by the present disclosure is to provide a display device in which stress applied to the display device during a winding process of the display device is reduced.

[0009] Still another object to be achieved by the present disclosure is to provide a display device in which the occurrence of cracks in a display panel is minimized by suppressing excessive bending of the display device in a boundary region between a flat portion and a first curved portion during winding of the display device.

[0010] The purpose of the present disclosure is not limited to the above-mentioned purpose, and those skilled in the art can clearly understand other purposes not mentioned above through the following description.

[0011] According to one aspect of the present disclosure, a display device includes: a display unit; and a roller configured so that the display unit is rolled around or unrolled from the roller, the roller including a flat portion, a first curved portion extending from the flat portion, and a second curved portion extending from the first curved portion toward the flat portion, wherein the radius of curvature of the first curved portion is greater than the radius of curvature of the second curved portion, and the radius of curvature of the display unit rolled around the second curved portion is greater than the radius of curvature of the second curved portion. Therefore, the second curved portion is formed to support the display unit so that the display unit is not bent at a small radius of curvature between the first curved portion and the flat portion, which makes it possible to minimize damage to the display device caused by excessive bending.

[0012] According to another aspect of the present disclosure, a display device includes: a display panel; and a roller configured so that the display panel is rolled around or unrolled from the roller, the roller including a flat portion, a first curved portion, and a second curved portion, the second curved portion being disposed between the first curved portion and the flat portion and having a radius of curvature smaller than that of the first curved portion, wherein a portion of the second curved portion protrudes further outward than one surface of the flat portion. Therefore, the second curved portion is formed to support the display panel between the first curved portion and the flat portion, which makes it possible to minimize cracks and defects in the display panel.

[0013] Additional details of example embodiments are included in the detailed description and the accompanying drawings.

[0014] According to the present disclosure, one or more curved portions are further provided between the flat portion and the first curved portion, so that the display panel can be supported and the display panel can be rolled up while having a large radius of curvature in the boundary area between the flat portion and the first curved portion, thereby solving the problems of cracks and defects.

[0015] According to the present disclosure, a plurality of bent portions are formed to allow the display panel to be slightly bent around the roller, which makes it possible to minimize a situation in which the display panel wound around the roller is excessively bent and damaged.

[0016] According to the present disclosure, damage to the pad region may be minimized by dispersing stress concentrated in a region adjacent to the pad region of the display panel in a boundary region between a flat portion and a curved portion.

[0017] The effects according to the present disclosure are not limited to those exemplified above, and more various effects are included in the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other aspects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description in conjunction with the accompanying drawings, in which:

[0019] Figure 1A and Figure 1B is a perspective view of a display device according to an embodiment of the present disclosure;

[0020] Figure 2 is a perspective view of a display device according to an embodiment of the present disclosure;

[0021] Figure 3 is a schematic cross-sectional view of a display device according to an embodiment of the present disclosure;

[0022] Figure 4A is an exploded perspective view for explaining a first cover and a second cover of a display device according to an embodiment of the present disclosure;

[0023] Figure 4B is a top plan view of a display unit of a display device according to an embodiment of the present disclosure;

[0024] Figure 5 is a top plan view of a display device according to an embodiment of the present disclosure;

[0025] Figure 6 is a cross-sectional view of a display device according to an embodiment of the present disclosure;

[0026] Figure 7 is an enlarged cross-sectional view of a display device according to an embodiment of the present disclosure;

[0027] Figure 8 is a cross-sectional view of a display device according to another embodiment of the present disclosure;

[0028] Fig. 9 is an enlarged cross-sectional view of a display device according to another embodiment of the present disclosure;

[0029] Fig. 10A and 10B is a perspective view of a roller of a display device according to still another embodiment of the present disclosure;

[0030] Fig.11 is an enlarged cross-sectional view of a roller of a display device according to still another embodiment of the present disclosure;

[0031] Fig. 12A is a schematic cross-sectional view of a roller of a display device according to an embodiment;

[0032] Fig. 12B is a diagram showing a distribution of stress applied to a display unit when a display unit of a display device according to an embodiment is rolled around a roller;

[0033] Fig.13Ais a schematic cross-sectional view of a roller of a display device according to a comparative example; and

[0034] Fig. 13B : is a diagram showing the distribution of stress applied to the display unit when the display unit of the display device according to the comparative example is rolled around a roller. DETAILED DESCRIPTION

[0035] The advantages and features of the present disclosure and the methods for achieving these advantages and features will become clear by reference to the exemplary embodiments described in detail below in conjunction with the accompanying drawings. However, the present disclosure is not limited to the exemplary embodiments disclosed herein, but will be implemented in various forms. These exemplary embodiments are provided only by way of example so that those skilled in the art can fully understand the disclosure of the present disclosure and the scope of the present disclosure. Therefore, the present disclosure will be limited only by the scope of the appended claims.

[0036] The shapes, sizes, ratios, angles, numbers, etc. shown in the accompanying drawings for describing the exemplary embodiments of the present disclosure are merely examples, and the present disclosure is not limited thereto. Throughout the specification, the same reference numerals generally represent the same elements. In addition, in the following description of the present disclosure, a detailed explanation of known related art may be omitted to avoid unnecessary confusion of the subject matter of the present disclosure. Terms such as "including", "having" and "consisting of..." used herein are generally intended to allow the addition of other components, unless these terms are used together with the term "only". Unless otherwise expressly stated, any reference to the singular may include the plural.

[0037] Even if not explicitly stated, the components are interpreted as including the ordinary error range.

[0038] When terms such as “on,” “above,” “below,” and “next” are used to describe the positional relationship between two components, one or more components may be located between the two components unless these terms are used together with the term “immediately” or “directly.”

[0039] When an element or a layer is referred to as being “on” another element or layer, the other layer or element may be directly on the other element or interposed between them.

[0040] Although the terms "first", "second", etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from other components. Therefore, the first component mentioned below can be the second component in the technical concept of the present disclosure.

[0041] Throughout the specification, like reference numerals generally refer to like elements.

[0042] For convenience of description, the size and thickness of each component shown in the drawings are illustrated, and the present disclosure is not limited to the size and thickness of the illustrated components.

[0043] The features of the various embodiments of the present disclosure may be partially or entirely coupled or combined with each other and may be technically interlocked and operated in various ways, and the embodiments may be performed independently or in association with each other.

[0044] Hereinafter, a display device according to an exemplary embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

[0045] A rollable display device refers to a display device that can display an image even when the rollable display device is rolled up. Compared with a general display device in the related art, the rollable display device may have higher flexibility. The shape of the rollable display device may be freely changed depending on whether the rollable display device is used. Specifically, when the rollable display device is not used, the rollable display device may be rolled up and stored in a reduced volume. On the contrary, when the rollable display device is used, the rolled-up rollable display device may be unfolded again and used.

[0046] Figure 1A and Figure 1B is a perspective view of a display device according to an embodiment of the present disclosure. Figure 1A and Figure 1B , a display device 100 according to an embodiment of the present disclosure includes a display unit DP and a housing unit HP.

[0047] The display unit DP is configured to display an image to a user. For example, a display element and circuits, lines, and components for operating the display element may be provided on the display unit DP. In this case, since the display device 100 according to an embodiment of the present disclosure is a rollable display device, the display unit DP may be configured to be rolled or unfolded. For example, the display unit DP may include a display panel having flexibility so as to be rolled or unfolded, and a first cover. FIG. 4A to FIG. 5 The display unit DP is described in more detail.

[0048] The housing unit HP is a housing capable of accommodating the display unit DP. The housing unit HP may have an opening portion HPO through which the display unit DP may be moved to the outside or inside of the housing unit HP.

[0049] At the same time, the display unit DP of the display device 100 can be Figure 1A The fully expanded state shown switches to Figure 1B The fully reeled state shown, or switching from the fully reeled state to the fully deployed state.

[0050] The driving unit is configured to roll or unroll the display unit DP to switch the display unit DP to a fully rolled state or a fully rolled state.

[0051] Figure 2 is a perspective view of a display device according to an embodiment of the present disclosure. Figure 3 is a schematic cross-sectional view of a display device according to an embodiment of the present disclosure. Figure 3 1 is a schematic cross-sectional view for explaining the roller 161 and the display unit DP of the display device 100 according to an embodiment of the present disclosure. For convenience of description, Figure 3 Only the housing unit HP, the roller 161 and the display unit DP are shown.

[0052] First, refer to Figure 2 The driving unit MP includes a roller unit 160 and a lifting unit 170 .

[0053] The roller unit 160 winds or unwinds the display unit DP fixed to the roller unit 160 while rotating clockwise or counterclockwise. The roller unit 160 includes a roller 161 and a roller supporting portion 162.

[0054] The roller 161 refers to a member around which the display unit DP is rolled. For example, the roller 161 may have a cylindrical shape. The lower edge of the display unit DP may be fixed to the roller 161. When the roller 161 rotates, the display unit DP having the lower edge fixed to the roller 161 may be rolled around the roller 161. Conversely, when the roller 161 rotates in the reverse direction, the display unit DP rolled around the roller 161 may be unrolled from the roller 161.

[0055] Reference Figure 3 , the roller 161 may have a cylindrical shape, wherein at least a portion of the outer circumferential surface of the roller 161 has a flat surface, and the rest of the outer circumferential surface has a curved surface. The roller 161 may have a cylindrical shape as a whole, but a portion of the roller 161 may have a flat surface. That is, a portion of the outer circumferential surface of the roller 161 is flat, and the rest of the outer circumferential surface is curved. For example, the roller 161 may have one or more curved portions and a flat portion. The flat portion of the roller 161 may be a portion on which a plurality of flexible films of the printed circuit board and the display unit DP are located. However, for convenience of description, Figure 3 The roller 161 is shown to have a single curved portion and a single flat portion. However, the number of curved portions and the number of flat portions are not limited thereto. Figure 6 and Figure 7 Describe the configuration.

[0056] Return to reference Figure 2, the roller supporting portion 162 supports the roller 161 at two opposite sides of the roller 161. Specifically, the roller supporting portion 162 is provided on the bottom surface HPF of the housing unit HP. In addition, the side surface of the upper end of the roller supporting portion 162 is coupled to the two opposite ends of the roller 161. Therefore, the roller supporting portion 162 can support the roller 161 so that the roller 161 is spaced apart from the bottom surface HPF of the housing unit HP. In this case, the roller 161 can be rotatably coupled to the roller supporting portion 162.

[0057] The lifting unit 170 moves the display unit DP in an upward / downward direction in conjunction with the operation of the roller unit 160. The lifting unit 170 includes a link unit 171, a head bar 172, a motor 175, and a rotating unit 176.

[0058] The connecting rod unit 171 of the lifting unit 170 includes a plurality of connecting rods 171a and 171b, and a hinge 171c configured to connect the plurality of connecting rods 171a and 171b. Specifically, the plurality of connecting rods 171a and 171b include a first connecting rod 171a and a second connecting rod 171b. The first connecting rod 171a and the second connecting rod 171b are rotatably fastened by the hinge 171c, while intersecting each other in a scissor shape. The connecting rod unit 171 may include a plurality of connecting rods intersecting each other. However, the number of connecting rods is not limited. The connecting rod unit 171 may include a single connecting rod. Therefore, when the connecting rod unit 171 moves in the upward / downward direction, the plurality of connecting rods may rotate in a direction toward or away from each other. The connecting rod unit 171 may include a plurality of connecting rods intersecting each other. However, the present disclosure is not limited thereto. The connecting rod unit 171 may include a single connecting rod that does not intersect.

[0059] The head bar 172 of the lifting unit 170 is fixed to the uppermost end of the display unit DP. The head bar 172 may be connected to the connecting rod unit 171, and the display unit DP may be moved in an upward / downward direction by the rotation of a plurality of connecting rods of the connecting rod unit 171. That is, the display unit DP may be moved in an upward / downward direction by the head bar 172 and the connecting rod unit 171.

[0060] The head bar 172 covers a portion of the display unit DP adjacent to the uppermost edge of the display unit DP so as not to cover an image displayed on the front surface of the display unit DP. The display unit DP and the head bar 172 may be fixed by screws, but the present disclosure is not limited thereto.

[0061] The motor 175 may be connected to a generator such as a separate external power source or an embedded battery and powered. The motor 175 generates a rotational force and provides a driving force to the rotation unit 176 .

[0062] The rotating unit 176 is connected to the motor 175 and is configured to convert the rotational motion provided by the motor 175 into a linear reciprocating motion. That is, the rotational motion of the motor 175 can be converted into a linear reciprocating motion of a structure fixed to the rotating unit 176. For example, the rotating unit 176 can be implemented as a ball screw mechanism including a shaft and a nut fastened to the shaft. However, the present disclosure is not limited thereto.

[0063] The motor 175 and the rotating unit 176 may operate together with the link unit 171 to move the display unit DP upward or downward. The link unit 171 may have a link structure and be repeatedly folded or unfolded by receiving driving force from the motor 175 and the rotating unit 176.

[0064] Specifically, in order to roll up the display unit DP, the motor 175 can be operated, and the structure of the rotating unit 176 can move linearly. That is, the portion of the rotating unit 176 connected to one end of the second connecting rod 171b can move linearly. Therefore, one end of the second connecting rod 171b can move toward the motor 175, and the plurality of connecting rods are folded, so that the height of the connecting rod unit 171 can be reduced. In addition, in the process of folding the plurality of connecting rods, the head rod 172 connected to the first connecting rod 171a also moves downward, and the end of the display unit DP connected to the head rod 172 also moves downward.

[0065] In order to unfold the display unit DP, the motor 175 can be operated, and the structure of the rotating unit 176 can move linearly. That is, the portion of the rotating unit 176 connected to one end of the second connecting rod 171b can move linearly. Therefore, one end of the second connecting rod 171b can be away from the motor 175, and a plurality of connecting rods can be unfolded so that the height of the connecting rod unit 171 can be increased. In addition, in the process of unfolding the plurality of connecting rods, the head rod 172 connected to the first connecting rod 171a also moves upward, and the display unit DP connected to the head rod 172 also moves upward.

[0066] Therefore, when the display unit DP is completely rolled around the roller 161, the link unit 171 of the lifting unit 170 remains folded. That is, when the display unit DP is completely rolled around the roller 161, the lifting unit 170 may have the lowest height. On the contrary, when the display unit DP is completely unfolded, the link unit 171 of the lifting unit 170 remains unfolded. That is, when the display unit DP is completely unfolded, the lifting unit 170 may have the highest height.

[0067] Meanwhile, in order to roll the display unit DP, the roller 161 may be rotated, and the display unit DP may be rolled around the roller 161. Figure 3For example, the lower edge of the display unit DP is connected to the roller 161. In addition, when the roller 161 rotates in the first direction DR1, ie, the clockwise direction, the display unit DP may be rolled such that the rear surface of the display unit DP is in close contact with the surface of the roller 161.

[0068] In order to unfold the display unit DP, the roller 161 may be rotated, and the display unit DP may be unfolded from the roller 161. Figure 3 , for example, when the roller 161 rotates in the second direction DR2, ie, the counterclockwise direction, the display unit DP wound around the roller 161 may be unrolled from the roller 161 and disposed outside the housing unit HP.

[0069] In some embodiments, a driving unit MP having other structures than the above driving unit MP may be applied to the display device 100. That is, components of the roller unit 160 and the lifting unit 170 may be changed, some components may be omitted, or other components may be added as long as the components can roll and unroll the display unit DP.

[0070] Figure 4A is an exploded perspective view of a first cover and a second cover for explaining a display device according to an embodiment of the present disclosure. Figure 4B is a top plan view of a display unit of a display device according to an embodiment of the present disclosure.

[0071] Reference Figure 4A and Figure 4B , the display unit DP includes a first cover 110a, a display panel 120, a plurality of flexible films 130, a printed circuit board 140, and a second cover 110b. However, the present disclosure is not limited thereto. The display unit DP may include only the display panel 120, the plurality of flexible films 130, and the printed circuit board 140. For convenience of description, Figure 4A and Figure 4B The cover portion 150 is omitted.

[0072] Reference Figure 4A and Figure 4B , the first cover 110a is disposed on the rear surface of the display panel 120 and supports the display panel 120. Since the first cover 110a is disposed on the rear surface of the display panel 120, the first cover 110a may be referred to as a back cover. The size of the first cover 110a may be greater than the size of the display panel 120. The first cover 110a may protect other components of the display unit DP from external influences.

[0073] The first cover 110a may be made of a material having rigidity. At least a portion of the first cover 110a may be flexible so as to be wound or unfolded together with the display panel 120. For example, the first cover 110a may be made of a metal material such as stainless steel (steel uses stainless steel (SUS)) or Invar alloy or a plastic material. However, the material of the first cover 110a may be variously changed according to the design, as long as the material of the first cover 110a satisfies physical property conditions such as thermal deformation, radius of curvature, rigidity, etc. However, the present disclosure is not limited thereto.

[0074] The first cover 110a includes a plurality of support areas PA and an extendable area MA. The plurality of support areas PA are areas where the plurality of opening portions 111 are not provided. The extendable area MA is an area where the plurality of opening portions 111 are provided. Specifically, the first cover 110a includes a first support area PA1, an extendable area MA, and a second support area PA2. The first support area PA1, the extendable area MA, and the second support area PA2 are provided in sequence from the uppermost end of the first cover 110a.

[0075] In this case, when the first cover 110a is rolled or unrolled in the column direction, the plurality of support areas PA and stretchable areas MA of the first cover 110a may be arranged in the column direction, such as Figure 4A In the case where the first cover 110a is rolled in the row direction, a plurality of support areas PA and stretchable areas MA may be provided in the row direction. However, the present disclosure is not limited thereto.

[0076] The first supporting area PA1 of the first cover 110a is the uppermost area of ​​the first cover 110a that is fastened to the head bar 172. A first fastening hole AH1 may be formed in the first supporting area PA1 so that the first supporting area PA1 is fastened to the head bar 172. For example, a screw is provided to pass through the first fastening hole AH1 and the head bar 172 so that the head bar 172 and the first supporting area PA1 may be fastened to each other. In addition, since the first supporting area PA1 is fastened to the head bar 172, when the connecting rod unit 171 fastened to the head bar 172 moves upward or downward, the first cover 110a may also move upward or downward. In addition, the display panel 120 attached to the first cover 110a may also move upward or downward. Figure 4A and Figure 4B Five first fastening holes AH1 are shown. However, the number of the first fastening holes AH1 is not limited thereto. In addition, a configuration has been described in which the first cover 110a is fastened to the head bar 172 by using the first fastening holes AH1. However, the present disclosure is not limited thereto, and the first cover 110a and the head bar 172 may be fastened to each other without fastening holes.

[0077] The stretchable area MA of the first cover 110a is an area extending downward from the first supporting area PA1 to the lower side of the first cover 110a. The stretchable area MA is an area provided with a plurality of opening portions 111 and attached to the display panel 120. Specifically, the stretchable area MA is an area where the roller 161 is rolled or unrolled together with the display panel 120. The stretchable area MA may overlap at least the display panel 120 among other components of the display unit DP.

[0078] The second support area PA2 of the first cover 110a is the lowermost area of ​​the first cover 110a extending from the extensible area MA. One end of the display panel 120 is disposed in the second support area PA2. For example, a pad area in the non-display area NA disposed at one end of the display panel 120 may be disposed in the second support area PA2.

[0079] Reference Figure 4A , the second fastening hole AH2 is provided in the second supporting area PA2. The second fastening hole AH2 may be a hole for fixing the cover part 150, the second cover 110b, and the first cover 110a, which will be described below. Figure 4A Nine second fastening holes AH2 are shown. However, the number of the second fastening holes AH2 is an example, and the present disclosure is not limited thereto.

[0080] Meanwhile, the plurality of opening portions 111 formed in the extensible area MA are not formed in the first supporting area PA1 and the second supporting area PA2. Specifically, the first fastening hole AH1 is formed in the first supporting area PA1, and the second fastening hole AH2 is formed in the second supporting area PA2. However, the plurality of opening portions 111 formed in the extensible area MA are not formed in the first supporting area PA1 and the second supporting area PA2. In addition, the first fastening hole AH1 and the second fastening hole AH2 are different in shape from the plurality of opening portions 111.

[0081] The first supporting area PA1 is an area fixed to the head bar 172. The second supporting area PA2 is an area that supports one end of the display panel 120, a plurality of flexible films 130, and a printed circuit board 140 in a flat manner. The first and second supporting areas may have a higher rigidity than the extensible area MA. In addition, since the first supporting area PA1 and the second supporting area PA2 have rigidity, the first supporting area PA1 and the second supporting area PA2 may be firmly fixed to the head bar 172 and the second cover 110b. The second supporting area PA2 may keep the pad area at one end of the printed circuit board 140 and the display panel 120 in a flat shape, thereby protecting the pad area of ​​the printed circuit board 140 and the display panel 120. Therefore, the display unit DP may be fixed to the head bar 172 of the driving unit MP and moved to the inside or outside of the housing unit HP by the operation of the driving unit MP. The second supporting area may protect the pad area at one end of the printed circuit board 140 and the display panel 120.

[0082] The plurality of opening portions 111 provided in the stretchable area MA of the first cover 110a may be deformed due to stress applied to the display unit DP while the display unit DP is rolled or unfolded. Specifically, the stretchable area MA of the first cover 110a may be deformed as the plurality of opening portions 111 shrink or expand while the display unit DP is rolled or unfolded. In addition, due to the shrinkage or expansion of the plurality of opening portions 111, the sliding of the display panel 120 provided on the stretchable area MA of the first cover 110a is minimized, so that the stress applied to the display panel 120 may be minimized.

[0083] The second cover 110b may be fastened to the first cover 110a and the roller 161, and connect the first cover 110a and the roller 161. As described above, the second cover 110b may connect the first cover 110a and the roller 161, and finally connect the roller 161 and the display panel 120 disposed on the first cover 110a. However, the present disclosure is not limited thereto. The shape or connection method of the second cover 110b may be variously changed according to the design, as long as the second cover 110b can be connected to the first cover 110a and the roller 161. However, the present disclosure is not limited thereto.

[0084] One end of the second cover 110b is the uppermost region of the second cover 110b and may overlap with one end of the first cover 110a. For example, one end of the second cover 110b may overlap with the second support area PA2. One end of the second cover 110b may be connected to a portion of the first cover 110a and overlap with a portion of the first cover 110a, or may be connected to a portion of the first cover 110a by using a connecting member, etc. However, the present disclosure is not limited thereto.

[0085] The second cover 110b may include a plurality of fastening parts FP overlapping with the first cover 110a. The plurality of fastening parts FP are provided at one end of the second cover 110b. In addition, a plurality of third fastening holes AH3 may be respectively provided in the plurality of fastening parts FP to be fastened to the first cover 110a. The plurality of fastening parts FP having the plurality of third fastening holes AH3 are spaced apart from each other so that a space in which the plurality of flexible films 130 can be bent can be ensured between the plurality of fastening parts FP. The third fastening holes AH3 may be holes for fixing the second cover 110b and the cover part 150 to be described below. Figure 4A Nine third fastening holes AH3 are shown. However, the number of the third fastening holes AH3 is an example, and the present disclosure is not limited thereto.

[0086] Figure 4A The second fastening holes AH2 and the third fastening holes AH3 for fastening the cover 150, the first cover 110a and the second cover 110b are respectively provided in the second supporting area PA2 of the first cover 110a and one end of the second cover 110b. However, the first cover 110a, the second cover 110b and the cover 150 can be fixed to each other without separate fastening holes.

[0087] Meanwhile, when the second supporting area PA2 and the plurality of fastening parts FP are wound around the roller 161, the outer peripheral surface of the roller 161 on which the second supporting area PA2 and the plurality of fastening parts FP overlap each other may be a flat portion. Therefore, regardless of the state in which the second supporting area PA2 is wound around the roller 161 or unwound from the roller 161, the second supporting area PA2 may always remain flat. The pad area of ​​the printed circuit board 140 and the display panel 120 disposed at one end on the second supporting area PA2 may also remain flat.

[0088] The area from one end to the other end of the second cover 110b is an area extending so that the display area AA of the display panel 120 can be set outside the housing unit HP. For example, when the first cover 110a and the display panel 120 are in a fully unfolded state, the area from the other end of the second cover 110b fixed to the roller 161 to the end of the second cover 110b where the multiple flexible films 130 and the printed circuit board 140 are set can be set inside the housing unit HP. The extensible area MA and the first support area PA1 on which the display area AA of the display panel 120 is set can be set outside the housing unit HP. That is, the area from the other end of the second cover 110b fixed to the roller 161 to the second support area PA2 and at least a portion of one end of the second cover 110b can be set inside the housing unit HP.

[0089] The other end of the second cover 110b is the lowermost end region of the second cover 110b that is fastened to the roller 161. A fourth fastening hole AH4 may be formed at the other end of the second cover 110b so that the second cover 110b is fastened to the roller 161. For example, a fastening member is provided to pass through the roller 161 and the fourth fastening hole AH4 so that the roller 161 may be fastened to the other end of the second cover 110b. In addition, since the other end of the second cover 110b is fastened to the roller 161, the display panel 120, the first cover 110a, and the second cover 110b may be rolled around or unrolled from the roller 161. Figure 4A Two fourth fastening holes AH4 are shown. However, the number of the fourth fastening holes AH4 is not limited thereto.

[0090] Meanwhile, the plurality of opening portions 111 formed in the ductile region MA of the first cover 110a may not be formed in the second cover 110b. Specifically, the third fastening hole AH3 and the fourth fastening hole AH4 are formed at one end and the other end of the second cover 110b. However, the plurality of opening portions 111 formed in the ductile region MA of the first cover 110a are not formed in the second cover 110b. In addition, the third fastening hole AH3 and the fourth fastening hole AH4 are different in shape from the plurality of opening portions 111.

[0091] The second cover 110b may be made of a flexible material so that the second cover 110b can be wound around the roller 161 or unfolded from the roller 161. For example, the second cover 110b may be made of a plastic material such as polyethylene terephthalate (PET). However, the material of the second cover 110b may be variously changed according to the design as long as the material of the second cover 110b satisfies physical property conditions such as thermal deformation amount, curvature radius, rigidity, etc. However, the present disclosure is not limited thereto.

[0092] Meanwhile, in the present specification, a configuration in which the first cover 110a and the second cover 110b are separately formed has been described. However, the present disclosure is not limited thereto. The first cover 110a and the second cover 110b may be integrated, but the present disclosure is not limited thereto.

[0093] Reference Figure 4B , the display panel 120 is disposed on one surface of the first cover 110a. The display panel 120 is disposed in the extensible area MA on one surface of the first cover 110a. The display panel 120 is a panel configured to display an image to a user. The display panel 120 may include a display element configured to display an image, a driving element configured to operate the display element, and a circuit configured to transmit various types of signals to the display element and the driving element.

[0094] The display element may have different configurations depending on the type of the display panel 120. For example, in the case where the display panel 120 is an organic light-emitting display panel, the display element may be an organic light-emitting element including an anode, an organic light-emitting layer, and a cathode. For example, in the case where the display panel 120 is a liquid crystal display panel, the display element may be a liquid crystal display element. In addition, since the display device 100 according to an embodiment of the present disclosure is a rollable display device, the display panel 120 may be implemented as a flexible display panel so as to be rolled around the roller 161 or unrolled from the roller 161.

[0095] The display panel 120 includes a display area AA and a non-display area NA.

[0096] The display area AA is an area of ​​the display panel 120 that displays an image. The display area AA may include a plurality of sub-pixels constituting a plurality of pixels, and a circuit configured to operate the plurality of sub-pixels. The plurality of sub-pixels are the smallest units constituting the display area AA. A display element may be provided in each of the plurality of sub-pixels. For example, the plurality of sub-pixels may each include a light-emitting element, the light-emitting element including an anode, a light-emitting portion, and a cathode. However, the present disclosure is not limited thereto. In addition, a driving circuit configured to operate the plurality of sub-pixels may include a driving element, a circuit, and the like. For example, the driving circuit may include, but is not limited to, a thin film transistor, a storage capacitor, a gate line, a data line, and the like.

[0097] The non-display area NA is an area where no image is displayed. Various lines and circuits for operating the organic light emitting elements in the display area AA are arranged in the non-display area NA. For example, the non-display area NA may include, but is not limited to, connection lines for transmitting signals to a plurality of sub-pixels and a driving circuit in the display area AA. The non-display area NA may include a driving IC, such as a gate driver IC and a data driver IC.

[0098] Meanwhile, the non-display area NA may include a pad area. The pad area is an area in which a plurality of pad electrodes are disposed. The plurality of pad electrodes are electrodes for electrically connecting the plurality of flexible films 130 and the display panel 120. The plurality of flexible films 130 and the display panel 120 may be electrically connected through the plurality of pad electrodes. In this case, in the non-display area NA, the pad area may be an area where the plurality of flexible films 130 are bonded. The pad area may be a non-display area NA overlapping with the second support area PA2 of the first cover 110a. However, the pad area may be formed in another part of the non-display area NA according to the arrangement of the plurality of flexible films 130. However, the present disclosure is not limited thereto.

[0099] Reference Figure 4B, a plurality of flexible films 130 are disposed at one end of the display panel 120. Each of the plurality of flexible films 130 is a film having various types of components, which are disposed on a base film having ductility so as to provide signals to a plurality of sub-pixels and a driving circuit in the display area AA. The plurality of flexible films 130 may be electrically connected to the display panel 120. The plurality of flexible films 130 are disposed at one end of the non-display area NA of the display panel 120, and may provide a power supply voltage, a data voltage, etc. to a plurality of sub-pixels and a driving circuit in the display area AA. At the same time, Figure 4B Eight flexible films 130 are shown. However, the number of the flexible films 130 may be variously changed according to the design. However, the present disclosure is not limited thereto.

[0100] Driver ICs such as gate driver ICs and data driver ICs may be disposed on the base film of the plurality of flexible films 130. The driver IC is a component configured to process data for displaying an image and process a driving signal for processing the data. Depending on the mounting method of the driver IC, the driver IC may be disposed in a manner such as a chip on glass (COG) method, a chip on film (COF) method, and a tape carrier package (TCP) method. However, in Figure 4B In the present invention, for convenience of description, a configuration in which a driving IC is mounted on a plurality of flexible films 130 by a chip on film method has been described. However, the present disclosure is not limited thereto.

[0101] At the same time, one end of each of the plurality of flexible films 130 may be bonded to the display panel 120, and the other end of each of the plurality of flexible films 130 may be bent toward the rear surface of the first cover 110a. The plurality of flexible films 130 may be bent through the space between the fastening parts FP so that the other end of each of the plurality of flexible films 130 may be disposed on the rear surface of the first cover 110a. One end of each of the plurality of flexible films 130 may be disposed on one surface of the first cover 110a, and the other end of each of the plurality of flexible films 130 may be disposed on a surface of the first cover 110a opposite to the one surface of the first cover 110a. Figure 6 This configuration is described in detail.

[0102] Reference Figure 4B , the printed circuit board 140 is disposed on the rear surface of the first cover 110a and is connected to the plurality of flexible films 130. That is, the printed circuit board 140 is disposed adjacent to the rear surface of the first cover 110a and is electrically connected to the plurality of flexible films 130. The printed circuit board 140 is a component configured to provide a signal to a driving IC of each of the plurality of flexible films 130. Various types of components for providing various signals (e.g., driving signals, data signals, etc.) to the driving IC may be disposed on the printed circuit board 140. At the same time, Figure 4BTwo printed circuit boards 140 are shown. However, the number of printed circuit boards 140 may be variously changed according to design. The present disclosure is not limited thereto.

[0103] Although in Figure 4B Although not shown in the figure, an additional printed circuit board connected to the printed circuit board 140 may be provided. For example, the printed circuit board 140 may be referred to as a source printed circuit board (source PCB (S-PCB)), on which a data driver is mounted. The additional printed circuit board connected to the printed circuit board 140 may be referred to as a control printed circuit board (control PCB (C-PCB)), on which a timing controller or the like is mounted. The additional printed circuit board may be provided in the roller 161, on the housing unit HP outside the roller 161, or directly adjacent to the printed circuit board 140.

[0104] Meanwhile, among the components of the display unit DP, the pad area, the plurality of flexible films 130, and the printed circuit board 140 of the display panel 120 are susceptible to external impact and may be easily damaged by the impact. Therefore, a cover 150 may be further provided to protect the pad area, the plurality of flexible films 130, and the printed circuit board 140 of the display panel 120. The cover 150 may be provided to surround the pad area, the plurality of flexible films 130, and the printed circuit board 140 of the display panel 120. In the process of repeatedly winding the display unit DP around the roller 161 or unwinding the display unit DP from the roller 161, the cover 150 may minimize the impact applied to the pad area, the plurality of flexible films 130, and the printed circuit board 140 of the display panel 120.

[0105] In addition, the roller 161 may further include a flat portion 161F and a plurality of bent portions 161R1 and 161R2, thereby minimizing the transmission of stress to the pad area when the pad area of ​​the display panel 120, the plurality of flexible films 130, and the printed circuit board 140 are bent and damaged or a portion of the display panel 120 is excessively bent during the process of rolling and unrolling the display unit DP.

[0106] In the following, reference will be made to Figures 5 to 7 The cover portion 150 and the roller 161 of the display device 100 according to an embodiment of the present disclosure are described in more detail.

[0107] Figure 5 is a top plan view of a display device according to an embodiment of the present disclosure. Figure 6 is a cross-sectional view of a display device according to an embodiment of the present disclosure. Figure 7 is an enlarged cross-sectional view of a display device according to an embodiment of the present disclosure.

[0108] Reference Figure 5 and Figure 6, the cover 150 is provided to accommodate and protect the pad area of ​​the display panel 120, the plurality of flexible films 130, and the printed circuit board 140. The cover 150 may be provided in the second support area PA2 of the first cover 110a and at one end of the second cover 110b, and connect the first cover 110a and the second cover 110b. In addition, the cover 150 may maintain the pad area of ​​the printed circuit board 140 and one end of the display panel 120 in a flat state, and protect the plurality of flexible films 130.

[0109] The cover 150 includes a top cover 153 , a bottom cover 152 , and a base plate 151 .

[0110] The top cover 153 is disposed on one surface of the display panel 120. The top cover 153 is disposed to cover the pad area and the plurality of flexible films 130 in the non-display area NA of the display panel 120. The top cover 153 may be disposed to cover only the pad area of ​​the non-display area NA, which is one end of the display panel 120, without covering the display area AA of the display panel 120. If the top cover 153 covers the display area AA, an image displayed in the display area AA may be blocked. Therefore, the top cover 153 may be disposed to overlap only the non-display area NA.

[0111] The top cover 153 may be made of a material having rigidity so that the top cover 153 is not deformed when the display unit DP is rolled. The top cover 153 may protect a pad region at one end of the display panel 120 and the plurality of flexible films 130 .

[0112] The outer surface of the top cover 153 may have a convex shape and be connected to the curved portion of the roller 161, thereby defining a circular shape or defining a circular shape of the curved portion connected to the roller 161. That is, one surface of the top cover 153 may be formed as a curved surface. In addition, when the display unit DP is rolled, the top cover 153 may define a circular shape connected to the curved portion of the roller 161 or define a circular shape of the curved portion connected to the roller 161.

[0113] The bottom cover 152 is disposed on a surface of the first cover 110a opposite to one surface of the first cover 110a (i.e., the rear surface of the first cover 110a). The bottom cover 152 is disposed between the first cover 110a and the printed circuit board 140. The bottom cover 152 may be fixed to one end of the second cover 110b and is disposed to correspond to a portion of the extensible area MA and the entire second support area PA2 of the first cover 110a. The pad area of ​​one end of the display panel 120, the plurality of flexible films 130, and the printed circuit board 140 may be located on the bottom cover 152.

[0114] The substrate 151 is disposed on the rear surface of the bottom cover 152. The substrate 151 may have a plate shape, and cover the exposed surface of the printed circuit board 140 and the rear surface of the bottom cover 152.

[0115] In this case, the first cover 110a and the second cover 110b may be fastened to each other by a fixing member passing through the top cover 153, the second cover 110b, the first cover 110a, the bottom cover 152, and the substrate 151. In this case, the fixing member may be, for example, a screw member such as a screw or a bolt. However, the present disclosure is not limited thereto.

[0116] The substrate 151 may be disposed to correspond to the position where the printed circuit board 140 is located on the bottom cover 152. The bottom cover 152 may have a groove corresponding in shape to the substrate 151, and the substrate 151 is located in the groove of the bottom cover 152. A surface formed by connecting one surface of the bottom cover 152 and one surface of the substrate 151 may be formed as a flat surface without a protruding portion.

[0117] Therefore, since the substrate 151 covers the exposed surface of the printed circuit board 140, the printed circuit board 140 can be housed without being exposed to the outside. In addition, since the rear surface of the bottom cover 152 has no protruding portion, when the cover 150 is rolled around the roller 161, the cover 150 can be completely located on the flat portion 161F of the roller 161.

[0118] The plurality of flexible films 130 may be bent from one end of the display panel 120 and disposed to surround the end of the first cover 110a. The flexible film 130 electrically connected to the pad area at one end of the display panel 120 may be bent from the end of the first cover 110a toward the rear surface of the bottom cover 152 and electrically connected to the printed circuit board 140 located on the rear surface of the bottom cover 152. In this case, the second cover 110b may include a plurality of fastening portions FP overlapping the first cover 110a. The plurality of flexible films 130 may be bent from the end of the first cover 110a through the space between the plurality of fastening portions FP.

[0119] A roller 161 connected to the second cover 110b is provided. The display panel 120 connected to the roller 161 through the second cover 110b can be rolled around or unrolled from the roller 161 by the rotation of the roller 161. An end of the second cover 110b may be connected to the outer peripheral surface of the roller 161. For example, the second cover 110b may be connected to the roller 161 because a fastening member is provided to pass through the roller 161 and the fourth fastening hole AH4 formed at the other end of the second cover 110b. Figure 6 It is shown that the other end of the second cover 110b is connected to the first curved portion 161R1 of the roller 161. However, the other end of the second cover 110b may be connected to the flat portion 161F or the second curved portion 161R2 of the roller 161. However, the present disclosure is not limited thereto.

[0120] The roller 161 includes a flat portion 161F, a first curved portion 161R1, and a second curved portion 161R2. The outer peripheral surface of the roller 161 includes the flat portion 161F, a first curved portion 161R1 extending from the flat portion 161F, and a second curved portion 161R2 extending from the first curved portion 161R1 toward the flat portion 161F.

[0121] The flat portion 161F of the roller 161 is a portion around which the pad area of ​​the display panel 120, the printed circuit board 140, and the plurality of flexible films 130 among the components of the display unit DP are rolled. The pad area of ​​the display panel 120, the printed circuit board 140, and the plurality of flexible films 130 rolled around the flat portion 161F may be supported by the flat portion 161F and the cover 150 to always remain flat.

[0122] The first curved portion 161R1 is a portion extending from the flat portion 161F. The first curved portion 161R1 is a portion extending from one end of the flat portion 161F while having a first curvature radius. Therefore, a portion of the display unit DP wrapped around the first curved portion 161R1 may be curved while having the first curvature radius.

[0123] The second curved portion 161R2 is a portion extending from the other end of the flat portion 161F toward the first curved portion 161R1. The second curved portion 161R2 is disposed between the first curved portion 161R1 and the flat portion 161F. A portion of the display panel 120 adjacent to the pad area may be wound around the second curved portion 161R2. The second radius of curvature of the second curved portion 161R2 may be smaller than the first radius of curvature of the first curved portion 161R1. The surface area of ​​the second curved portion 161R2 may be smaller than the surface area of ​​the first curved portion 161R1. For example, the first radius of curvature of the first curved portion 161R1 may be about 40R, and the radius of curvature of the second curved portion 161R2 may be about 6R.

[0124] One surface of the bottom cover 152 of the cover portion 150 supporting the display panel 120 and the first cover 110a may be disposed on the same plane as the tangent plane of the second curved portion 161R2. The first cover 110a supporting the pad area of ​​the display panel 120 disposed in the cover portion 150 may be disposed on the same plane as the tangent plane of the second curved portion 161R2. Figure 6As shown, the first curved portion 161R1 is disposed on one surface of the flat portion 161F based on the flat portion 161F. However, a portion of the second curved portion 161R2 may be disposed on one surface of the flat portion 161F, and the remaining portion of the second curved portion 161R2 may be disposed below one surface of the flat portion 161F. For example, an imaginary plane X extending from one surface of the bottom cover 152 may be adjacent to the second curved portion 161R2. One surface of the bottom cover 152 may be disposed on the same plane as the outer peripheral surface of the second curved portion 161R2 of the roller 161. In this case, the portion of the display panel 120 extending to the outside of the cover portion 150 may be disposed on the same plane as the pad area inside the cover portion 150 through the second curved portion 161R2.

[0125] In this case, the display panel 120 and the first cover 110a wound around the second curved portion 161R2 having the second radius of curvature may be bent while having a radius of curvature greater than the second radius of curvature. A portion of the display panel 120 and the first cover 110a extending to the outside of the cover portion 150 is adjacent to a portion of the second curved portion 161R2. Therefore, when the display panel 120 and the first cover 110a are wound around the second curved portion 161R2, the display panel 120 and the first cover 110a may be bent while having a radius of curvature different from the second radius of curvature of the second curved portion 161R2. That is, since the display panel 120 and the first cover 110a are bent while only adjacent to a portion of the second curved portion 161R2, the radius of curvature of the display panel 120 and the first cover 110a bent while being wound around the second curved portion 161R2 may be different from the second radius of curvature of the second curved portion 161R2. In addition, since the display panel 120 and the first cover 110a are bent to a minimum while abutting only a portion of the second curved portion 161R2, the display panel 120 and the first cover 110a can be bent while having a radius of curvature greater than the second radius of curvature of the second curved portion 161R2. For example, when the second radius of curvature of the second curved portion 161R2 is 6R, the display unit DP can be rolled while being bent on the second curved portion 161R2 with a radius of curvature of about 32R.

[0126] Specifically, the outer peripheral surface of the second curved portion 161R2 is disposed on the same plane as an imaginary plane X extending from one surface of the bottom cover 152 supporting the first cover 110a and one end of the display panel 120 disposed in the cover portion 150. Therefore, the display panel 120 and the first cover 110a extending to the outside of the cover portion 150 can be rolled while maintaining a state close to a flat state between the cover portion 150 and the second curved portion 161R2. Therefore, the second curved portion 161R2 protrudes to the outside of the flat portion 161F to correspond to one surface of the bottom cover 152. Therefore, the display unit DP is not excessively bent between the flat portion 161F and the second curved portion 161R2.

[0127] If there are only the first curved portion 161R1 and the flat portion 161F without the second curved portion 161R2, a portion of the display panel 120 may be bent while being excessively bent in the boundary area between the first curved portion 161R1 and the flat portion 161F. Specifically, the area between the first curved portion 161R1 and the flat portion 161F is a small curvature area with a small radius of curvature. For this reason, the display panel 120 wound between the first curved portion 161R1 and the flat portion 161F may be easily damaged due to being bent to have a small radius of curvature. In addition, the display panel 120 and the first cover 110a outside the cover portion 150 may be wound while being excessively bent due to the level difference between the flat portion 161F, the substrate 151, and the bottom cover 152 supporting one end of the display panel 120. In this case, the portion of the display panel 120 adjacent to the pad area is repeatedly and excessively bent, which may affect the pad area or damage the pad area.

[0128] Meanwhile, the second curved portion 161R2 may not be disposed between the first curved portion 161R1 and one end of the flat portion 161F. The second cover 110b is first rolled between the first curved portion 161R1 and one end of the flat portion 161F. Thereafter, the display panel 120 may be rolled along a curved surface defined by the first curved portion 161R1 and the top cover 153 of the cover portion 150. Therefore, the display panel 120 may be rolled while being slightly bent between the first curved portion 161R1 and one end of the flat portion 161F. Therefore, the second curved portion 161R2 that supports the display panel 120 to suppress the display panel 120 from bending with a small radius of curvature may not be disposed between the first curved portion 161R1 and one end of the flat portion 161F.

[0129] The display device 100 according to an embodiment of the present disclosure includes a cover 150, which is configured to support the pad area of ​​the display panel 120 and the printed circuit board 140 in a flat state. Therefore, damage to the display panel 120 and the printed circuit board 140 can be minimized. Specifically, when the display unit DP is rolled around the roller 161, the first cover 110a and the second cover 110b can be rolled while bending along the shape of the roller 161. In addition, the display panel 120 and the printed circuit board 140 can also be rolled while bending along the shape of the roller 161. At the same time, in the process of repeatedly rolling and unrolling the display unit DP, cracks are likely to occur near the edge of the display panel 120. For example, when the pad area of ​​the display panel 120 is repeatedly bent, the components (e.g., a plurality of pad electrodes and various types of lines made of a metal material having hardness and low ductility) disposed on the pad area may be relatively easy to crack due to stress. The crack may extend to other parts of the display panel 120 and cause defects in the display device 100. In addition, when the printed circuit board 140 made of a hard material is bent, the printed circuit board 140 may be damaged. Therefore, the pad area of ​​the display panel 120 and the printed circuit board 140 are arranged in the cover 150 made of a material having rigidity. Therefore, the pad area of ​​the display panel 120 and the printed circuit board 140 can be kept flat and protected. In addition, a portion of the roller 161 around which the cover 150 is wound has a flat portion. Therefore, the pad area, the printed circuit board 140 and the cover 150 can be wound around the roller 161 while remaining flat. Therefore, the display device 100 according to an embodiment of the present disclosure includes a cover 150 arranged to support the pad area and the printed circuit board 140. Therefore, the pad area and the printed circuit board 140 can be kept flat and protected from external impact. In addition, in the display device 100 according to an embodiment of the present disclosure, the flat portion is formed on the outer peripheral surface of the roller 161, so that the pad area and the printed circuit board 140 will not bend, and the damage to the display panel 120 and the printed circuit board 140 can be minimized.

[0130] In the display device 100 according to an embodiment of the present disclosure, the second curved portion 161R2 is disposed between the flat portion 161F of the roller 161 and the first curved portion 161R1. Therefore, it is possible to minimize the situation in which the display panel 120 is damaged due to excessive bending in the boundary area between the first curved portion 161R1 and the flat portion 161F. The second curved portion 161R2 supports the display panel 120 so that the display panel 120 is rolled up while having a gentler radius of curvature. Specifically, the outer peripheral surface of the second curved portion 161R2 is disposed on the same plane as one end of the bottom cover 152 supporting the display panel 120 and one surface of the first cover 110a. Therefore, a portion of the display panel 120 disposed outside the cover portion 150 can be supported by the second curved portion 161R2 so as to be rolled up in a state close to a straight line, wherein one end of the display panel 120 is disposed inside the cover portion 150. In addition, a portion of the display panel 120 adjacent to the pad region of the display panel 120 outside the cover portion 150 may be adjacent to only a portion of the second curved portion 161R2 and be rolled to have a curvature radius that is gentler than the second curvature radius of the second curved portion 161R2. Therefore, the situation in which the stress that occurs when the display panel 120 is rolled is transferred to the pad region can be minimized. Therefore, in the display device 100 according to an embodiment of the present disclosure, the second curved portion 161R2 may be disposed between the first curved portion 161R1 and the flat portion 161F. Therefore, it is possible to suppress a portion of the display unit DP disposed outside the cover portion 150 from being excessively bent in the boundary region between the first curved portion 161R1 and the flat portion 161F, and minimize damage to the pad region caused by the stress transferred to the pad region.

[0131] Figure 8 is a cross-sectional view of a display device according to another embodiment of the present disclosure. Fig. 9 is an enlarged cross-sectional view of a display device according to another embodiment of the present disclosure. Figure 8 and Fig. 9 The display device 800 shown in FIG. 1 is similar in configuration to that shown in FIG. Figure 7 The display device 100 shown is substantially the same except that the roller 861 further includes a third curved portion 861R3 and a fourth curved portion 861R4. Therefore, repeated description of the same components will be omitted.

[0132] Reference Figure 8 and Fig. 9, the roller 861 includes a flat portion 861F, a first curved portion 861R1, a second curved portion 861R2, a third curved portion 861R3 and a fourth curved portion 861R4. The first curved portion 861R1 is a portion extending from one end of the flat portion 861F and having a first radius of curvature. The second curved portion 861R2 is a portion extending from the other end of the flat portion 861F and having a second radius of curvature. The third curved portion 861R3 is a portion extending from the second curved portion 861R2 toward the first curved portion 861R1 and having a third radius of curvature. The fourth curved portion 861R4 is a portion extending from the third curved portion 861R3 toward the first curved portion 861R1 and having a fourth radius of curvature. The fourth curved portion 861R4 may be disposed between the third curved portion 861R3 and the first curved portion 861R1.

[0133] Among the plurality of curved portions 861R1, 861R2, 861R3, and 861R4, the first radius of curvature of the first curved portion 861R1 may be the largest. In addition, among the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4, the second radius of curvature of the second curved portion 861R2 closest to the flat portion 861F may be the largest, and the fourth radius of curvature of the fourth curved portion 861R4 farthest from the flat portion 861F may be the smallest. The third radius of curvature of the third curved portion 861R3 has a value between the second radius of curvature and the fourth radius of curvature. For example, the first radius of curvature of the first curved portion 861R1 may be 40R, the second radius of curvature of the second curved portion 861R2 may be 6R, the third radius of curvature of the third curved portion 861R3 may be 5R, and the fourth radius of curvature of the fourth curved portion 861R4 may be 4R.

[0134] The radius of curvature of the display panel 120 rolled around the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 of the roller 861 may have a value greater than the second, third, and fourth curvature radii. The display unit DP may be rolled while only abutting a portion of the second curved portion 861R2, a portion of the third curved portion 861R3, and a portion of the fourth curved portion 861R4. The track defined by the portion of the second curved portion 861R2 abutting the display unit DP, the portion of the third curved portion 861R3 abutting the display unit DP, and the portion of the fourth curved portion 861R4 abutting the display unit DP may be greater than the second, third, and fourth curvature radii. For example, the display unit DP may be rolled around the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 while being bent at a radius of curvature of approximately 32R.

[0135] Meanwhile, the radius of curvature means the value of the radius of the circular arc. As the radius of curvature increases, the size of the circle will increase, and the surface area of ​​the curved portion will also increase. For example, the surface area of ​​the first curved portion 861R1 having the first radius of curvature of the maximum value may be the largest. The surface area of ​​the fourth curved portion 861R4 having the fourth radius of curvature of the minimum value may be the smallest. In addition, the surface area of ​​the second curved portion 861R2 having the second radius of curvature smaller than the first radius of curvature of the first curved portion 861R1 may be smaller than the surface area of ​​the first curved portion 861R1. The surface area of ​​the third curved portion 861R3 having the third radius of curvature smaller than the second radius of curvature of the second curved portion 861R2 may be smaller than the surface area of ​​the second curved portion 861R2.

[0136] In addition, the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 may be sequentially disposed between the flat portion 861F and the first curved portion 861R1. Therefore, the difference between the radius of curvature of the display panel 120 wrapped around the first curved portion 861R1, the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 may be gradually reduced. If the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 have the same radius of curvature and the same surface area, the radius of curvature of the display panel 120 may be rapidly changed in the boundary region between the fourth curved portion 861R4 and the first curved portion 861R1. In contrast, in the case where the curvature radius and the surface area of ​​the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 are sequentially reduced, the curvature radius of the display panel 120 wound around the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 can be gradually changed, which can allow the curvature radius of the display panel 120 not to change rapidly between the fourth curved portion 861R4 and the first curved portion 861R1. Therefore, the curvature radius of the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 decreases as the distance from the flat portion 861F increases. Therefore, the difference between the curvature radius of the display panel 120 wound around the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 and the curvature radius of the display panel 120 wound around the first curved portion 861R1 can be reduced, thereby minimizing damage to the display panel 120.

[0137] at the same time, Figure 8 and Fig. 9The roller 861 is shown to include four curved portions. However, the roller 861 may include only the first curved portion 861R1, the second curved portion 861R2, and the third curved portion 861R3, or include additional curved portions. The number of curved portions is not limited thereto.

[0138] Therefore, in the display device 800 according to another embodiment of the present disclosure, a plurality of curved portions 861R2, 861R3, and 861R4 are formed in the boundary region between the first curved portion 861R1 and the flat portion 861F of the roller 861, so that the display unit DP can be supported to be rolled while being slightly bent. Specifically, a portion of the display panel 120 rolled between the flat portion 861F and the second curved portion 861R2 is adjacent to the pad region. For this reason, the stress that occurs when a portion of the display panel 120 is bent may be transferred to the pad region and cause damage to the pad region. However, the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 can support the display panel 120 adjacent to the pad region, so that the display panel 120 is rolled with a larger radius of curvature. Therefore, the damage to the pad region caused by the process of repeatedly rolling and unfolding the display panel 120 can be reduced. In addition, the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 may gradually change the radius of curvature of a portion of the display panel 120 wound between the first curved portion 861R1 and the flat portion 861F. Therefore, in the display device 800 according to an embodiment of the present disclosure, the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 are disposed between the first curved portion 861R1 and the flat portion 861F. Therefore, the radius of curvature of the display panel 120 wound around the second curved portion 861R2, the third curved portion 861R3, and the fourth curved portion 861R4 may be gradually changed, and damage to the display device 800 may be minimized.

[0139] Fig. 10A and Fig. 10B is a perspective view of a roller of a display device according to still another embodiment of the present disclosure. Fig.11 is an enlarged cross-sectional view of a roller of a display device according to still another embodiment of the present disclosure. Fig. 10A is a perspective view of a main roller 1061 a of the roller 1061 of the display device 1000 according to an embodiment of the present disclosure. Fig. 10B is a perspective view of a first auxiliary roller 1061 b of the roller 1061 of the display device 1000 according to an embodiment of the present disclosure. FIG. 10A to FIG. 11 The display device 1000 shown in FIG. 1 is similar in configuration to the display device 1000 shown in FIG. Figure 8 and Fig. 9The display device 800 shown is substantially the same except for the roller 1061. Therefore, repeated description of the same components will be omitted.

[0140] Reference Fig. 10A and Fig.11 The roller 1061 includes a main roller 1061a, a first auxiliary roller 1061b, a second auxiliary roller 1061c and a third auxiliary roller 1061d.

[0141] The main roller 1061a is a roller having a flat portion 1061F and a first curved portion 1061R1. The second cover 110b may be connected to the main roller 1061a so that the display unit DP may be rolled around or unrolled from the main roller 1061a.

[0142] The main roller 1061a includes an opening area 1061O and a plurality of coupling holes 1061H. The opening area 1061O is an area formed by opening a portion of the first curved portion 1061R1. The first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d may be partially disposed in the main roller 1061a through the opening area 1061O.

[0143] The plurality of coupling holes 1061H of the main roller 1061a are holes formed to couple the first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d to the main roller 1061a. The plurality of coupling holes 1061H may be provided at two opposite ends of the main roller 1061a and formed adjacent to the first curved portion 1061R1 or the opening area 1061O. In this case, the shortest straight-line distances from the plurality of coupling holes 1061H to the outer peripheral surface, i.e., the first curved portion 1061R1 of the main roller 1061a, may be equal to each other and be D1. For example, the shortest straight-line distance from the coupling hole 1061H coupled to the first auxiliary roller 1061b to the first curved portion 1061R1, the shortest straight-line distance from the coupling hole 1061H coupled to the second auxiliary roller 1061c to the first curved portion 1061R1, and the shortest straight-line distance from the coupling hole 1061H coupled to the third auxiliary roller 1061d to the first curved portion 1061R1 may be equal to each other, which is D1.

[0144] In addition, when the central axes AX of the first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d are respectively inserted into the plurality of coupling holes 1061H, the first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d can be coupled to the main roller 1061a. Therefore, the roller 1061 can be easily and conveniently manufactured by coupling the central axes AX of the plurality of auxiliary rollers 1061b, 1061c, and 1061d to the main roller 1061a. However, the main roller 1061a, the first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d can be coupled by other methods instead of the plurality of coupling holes 1061H. However, the present disclosure is not limited thereto.

[0145] Reference Fig. 10B , the first auxiliary roller 1061b, the second auxiliary roller 1061c and the third auxiliary roller 1061d are coupled to the main roller 1061a. The first auxiliary roller 1061b, the second auxiliary roller 1061c and the third auxiliary roller 1061d are configured to support the display unit DP so that the display unit DP is wound with a larger radius of curvature in the area between the flat portion 1061F and the first curved portion 1061R1. The display unit DP can be wound while only abutting a portion of the first auxiliary roller 1061b, a portion of the second auxiliary roller 1061c and a portion of the third auxiliary roller 1061d. In addition, the track defined by the portion of the first auxiliary roller 1061b adjacent to the display unit DP, the portion of the second auxiliary roller 1061c adjacent to the display unit DP and the portion of the third auxiliary roller 1061d adjacent to the display unit DP can be greater than the radius of curvature of the first auxiliary roller 1061b, the radius of curvature of the second auxiliary roller 1061c and the radius of curvature of the third auxiliary roller 1061d. Therefore, the curvature radius of the display unit DP wound along the trajectory around the first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d may be greater than the curvature radius of the first auxiliary roller 1061b, the curvature radius of the second auxiliary roller 1061c, and the curvature radius of the third auxiliary roller 1061d. Therefore, the first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d may prevent the display unit DP from being wound while being bent with a relatively small curvature radius in an area between the first curved portion 1061R1 and the flat portion 1061F (particularly at a portion of the first curved portion 1061R1 adjacent to the flat portion 1061F), thereby minimizing the stress transferred to the pad area of ​​the display panel 120.

[0146] The first auxiliary roller 1061b is a roller configured to define the second curved portion 1061R2 and having a central axis AX coupled to two opposite ends of the main roller 1061a. The outer peripheral surface of the first auxiliary roller 1061b may correspond to the second curved portion 1061R2. A portion of the first auxiliary roller 1061b may protrude outside the first curved portion 1061R1 of the main roller 1061a and define the second curved portion 1061R2. The rest of the first auxiliary roller 1061b may be disposed in the main roller 1061a through the opening area 1061O. Therefore, the main roller 1061a and the first auxiliary roller 1061b may be used as rollers defining the flat portion 1061F, the first curved portion 1061R1, and the second curved portion 1061R2.

[0147] Among the plurality of auxiliary rollers 1061b, 1061c, and 1061d, the first auxiliary roller 1061b may be disposed closest to the flat portion 1061F of the main roller 1061a. For example, when the center axis AX of the first auxiliary roller 1061b is inserted into the coupling holes 1061H disposed at both opposite ends of the main roller 1061a and disposed closest to the flat portion 1061F among the plurality of coupling holes 1061H, the first auxiliary roller 1061b and the main roller 1061a may be coupled to each other.

[0148] The second auxiliary roller 1061c is a roller configured to define the third curved portion 1061R3 and having a central axis AX coupled to two opposite ends of the main roller 1061a. The outer peripheral surface of the second auxiliary roller 1061c may correspond to the third curved portion 1061R3. A portion of the second auxiliary roller 1061c may protrude outside the first curved portion 1061R1 of the main roller 1061a and define the third curved portion 1061R3. The rest of the second auxiliary roller 1061c may be arranged in the main roller 1061a through the opening area 1061O. Therefore, the main roller 1061a, the first auxiliary roller 1061b and the second auxiliary roller 1061c may be used as rollers defining the flat portion 1061F, the first curved portion 1061R1, the second curved portion 1061R2 and the third curved portion 1061R3.

[0149] The second auxiliary roller 1061c may be disposed adjacent to the first auxiliary roller 1061b. The first auxiliary roller 1061b may be disposed between the second auxiliary roller 1061c and the flat portion 1061F. For example, when the central axis AX of the second auxiliary roller 1061c is inserted into the coupling holes 1061H disposed at two opposite ends of the main roller 1061a and disposed adjacent to the coupling holes 1061H coupled to the first auxiliary roller 1061b, the second auxiliary roller 1061c and the main roller 1061a may be coupled to each other.

[0150] The third auxiliary roller 1061d is a roller configured to define the fourth curved portion 1061R4 and having a central axis AX coupled to two opposite ends of the main roller 1061a. The outer peripheral surface of the third auxiliary roller 1061d may correspond to the fourth curved portion 1061R4. A portion of the third auxiliary roller 1061d may protrude outside the first curved portion 1061R1 of the main roller 1061a and define the fourth curved portion 1061R4. The rest of the third auxiliary roller 1061d may be arranged in the main roller 1061a through the opening area 1061O. Therefore, the main roller 1061a, the first auxiliary roller 1061b, the second auxiliary roller 1061c and the third auxiliary roller 1061d may be used as rollers defining the flat portion 1061F, the first curved portion 1061R1, the second curved portion 1061R2, the third curved portion 1061R3 and the fourth curved portion 1061R4.

[0151] Among the plurality of auxiliary rollers 1061b, 1061c, and 1061d, the third auxiliary roller 1061d may be disposed farthest from the flat portion 1061F of the main roller 1061a. For example, when the center axis AX of the third auxiliary roller 1061d is inserted into the coupling hole 1061H disposed at two opposite ends of the main roller 1061a among the plurality of coupling holes 1061H and disposed in the coupling hole 1061H farthest from the flat portion 1061F, the third auxiliary roller 1061d and the main roller 1061a may be coupled to each other.

[0152] Meanwhile, the radius of the plurality of auxiliary rollers 1061b, 1061c, and 1061d may increase as the distance from the flat portion 1061F decreases. For example, among the plurality of auxiliary rollers 1061b, 1061c, and 1061d, the first radius R1 of the first auxiliary roller 1061b closest to the flat portion 1061F may be the largest, and the third radius R3 of the third auxiliary roller 1061d farthest from the flat portion 1061F may be the smallest. In addition, the second radius R2 of the second auxiliary roller 1061c disposed between the first auxiliary roller 1061b and the third auxiliary roller 1061d may have a value between the first radius R1 and the third radius R3.

[0153] In this case, the shortest straight-line distances from the plurality of coupling holes 1061H respectively coupled to the plurality of auxiliary rollers 1061b, 1061c, and 1061d to the outer peripheral surface of the main roller 1061a are equal to each other and are D1. In addition, the plurality of auxiliary rollers 1061b, 1061c, and 1061d respectively coupled to the plurality of coupling holes 1061H and having different radii may have portions of different volumes protruding outside the main roller 1061a. For example, the portion of the first auxiliary roller 1061b having the largest first radius R1 protruding outside the main roller 1061a may have the largest volume. The portion of the third auxiliary roller 1061d having the smallest third radius R3 protruding outside the main roller 1061a may have the smallest volume.

[0154] at the same time, FIG. 10A to FIG. 11 It is shown that the first auxiliary roller 1061b, the second auxiliary roller 1061c, and the third auxiliary roller 1061d are used. However, only the first auxiliary roller 1061b may be used, or additional auxiliary rollers may be added. The number of the auxiliary rollers 1061b, 1061c, and 1061d is not limited thereto.

[0155] In the display device 1000 according to an embodiment of the present disclosure, the roller 1061 including the flat portion 1061F and the plurality of curved portions 1061R1, 1061R2, 1061R3, and 1061R4 may be implemented by coupling the main roller 1061a and the plurality of auxiliary rollers 1061b, 1061c, and 1061d. Specifically, a portion of the first curved portion 1061R1 of the main roller 1061a including the flat portion 1061F and the first curved portion 1061R1 may be opened to form an opening area 1061O through which a vacant space in the main roller 1061a is exposed, and a plurality of coupling holes 1061H are formed at both opposite ends of the main roller 1061a. In addition, the auxiliary rollers 1061b, 1061c, and 1061d may be coupled to the main roller 1061a by inserting the central axes AX of the plurality of auxiliary rollers 1061b, 1061c, and 1061d into the plurality of coupling holes 1061H. In this case, the plurality of auxiliary rollers 1061b, 1061c, and 1061d may be partially disposed outside the main roller 1061a, and the remaining portions of the plurality of auxiliary rollers 1061b, 1061c, and 1061d may be disposed in the main roller 1061a through the opening area 1061O. In addition, the outer peripheral surfaces of the plurality of auxiliary rollers 1061b, 1061c, and 1061d disposed outside the main roller 1061a may define a second curved portion 1061R2, a third curved portion 1061R3, and a fourth curved portion 1061R4, respectively. Therefore, when the plurality of auxiliary rollers 1061b, 1061c, and 1061d are coupled to the main roller 1061a, the display panel 120 can be supported so that the display panel 120 can be rolled up while having a larger radius of curvature in the boundary region between the first curved portion 1061R1 and the flat portion 1061F. Therefore, in the display device 1000 according to an embodiment of the present disclosure, the plurality of auxiliary rollers 1061b, 1061c, and 1061d having different radii are coupled to the main roller 1061a. Therefore, the roller 161 including the flat portion 1061F and the plurality of curved portions 1061R1, 1061R2, 1061R3, and 1061R4 can be easily formed.

[0156] In the following, reference will be made to FIG. 12A to FIG. 13B Describes the effect of reducing the stress applied to the display panel 120 during the winding process in the following configuration: wherein, in the display devices 100, 800 and 1000 according to various embodiments of the present disclosure, the rollers 161, 861 and 1061 have a plurality of curved portions 161R1, 861R1, 1061R1, 161R2, 861R2, 1061R2, 861R3, 1061R3, 861R and 1061R4.

[0157] Fig. 12Ais a schematic cross-sectional view of a roller of a display device according to an embodiment. Fig. 12B is a diagram showing distribution of stress applied to the display unit when the display unit of the display device according to the embodiment is rolled around a roll. Fig.13A is a schematic cross-sectional view of a roller of a display device according to a comparative example. Fig. 13B is a diagram showing distribution of stress applied to a display unit when a display unit of a display device according to a comparative example is rolled around a roll.

[0158] Reference Fig. 12A The roller 1261 of the display device 1200 according to the embodiment includes a flat portion 1261F, a first curved portion 1261R1 extending from the flat portion 1261F, a second curved portion 1261R2 disposed between the first curved portion 1261R1 and the flat portion 1261F, and a third curved portion 1261R3 disposed between the second curved portion 1261R2 and the first curved portion 1261R1. The first curved portion 1261R1 has the largest curvature radius, and the third curved portion 1261R3 has the smallest curvature radius.

[0159] Reference Fig.13A The roller 61 of the display device 10 according to the comparative example includes a flat portion 61F and a first curved portion 61R1. Compared with the roller 1261 of the display device 1200 according to the embodiment, the roller 61 of the display device 10 according to the comparative example includes only the first curved portion 61R1, and does not include the second curved portion 61R2 and the third curved portion 61R3.

[0160] At the same time, Fig. 12B and Fig. 13B In the figure, the color in each area indicates the magnitude of stress. Areas close to the dark area have low stress, and areas close to the light area have high stress.

[0161] Reference Fig. 12A When the display unit DP is rolled around the roller 1261 of the display device 1200 according to the embodiment, the display unit DP may be rolled while being bent by the second curved portion 1261R2 and the third curved portion 1261R3 in a boundary region between the first curved portion 1261R1 and the flat portion 1261F with a curvature radius greater than that of the second curved portion 1261R2 and the third curved portion 1261R3. The second curved portion 1261R2 and the third curved portion 1261R3 may support the display unit DP so that the display unit DP has a large curvature radius in a boundary region A between the first curved portion 1261R1 and the flat portion 1261F.

[0162] Reference Fig. 12B, in the stress distribution applied to the display unit DP, the stress applied to the boundary region A is about 33 MPa. It can be seen that since the display unit DP is wound around the flat portion 1261F and the first curved portion 1261R1 while having a relatively large radius of curvature, a relatively low stress is applied to the region corresponding to the flat portion 1261F and the first curved portion 1261R1. Therefore, it can be seen that the stress of about 33 MPa is widely distributed in the boundary region A corresponding to the second curved portion 1261R2 and the third curved portion 1261R3.

[0163] Reference Fig.13A , when the display unit DP is rolled around the roller 61 of the display device 10 according to the comparative example, the display unit DP may be rolled while being bent in a boundary region B between the first curved portion 61R1 and the flat portion 61F with a curvature radius smaller than that of the first curved portion 61R1. The boundary region B between the flat portion 61F and the first curved portion 61R1 may be a region bent with a curvature radius smaller than that of the first curved portion 61R1. Therefore, the display unit DP may be bent in the boundary region B with a curvature radius smaller than that of the first curved portion 61R1.

[0164] Reference Fig. 13B , in the stress distribution applied to the display unit DP, the stress applied to the boundary region B is about 51 MPa. Even in the case of the display device 10 according to the comparative example, a relatively low stress is applied to the partial region of the display unit DP wound around the flat portion 61F and the first curved portion 61R1. However, the stress of 51 MPa is concentrated in a very localized region of the boundary region B between the first curved portion 61R1 and the flat portion 61F. In this case, in the process of repeatedly winding and unwinding the display unit DP, the display unit DP is likely to be damaged by the stress of 51 MPa concentrated in the partial region of the display unit DP.

[0165] In summary, in the display device 1200 according to the embodiment, the second curved portion 1261R2 and the third curved portion 1261R3 are formed between the first curved portion 1261R1 and the flat portion 1261F, so that relatively low stress is dispersed to a wide area of ​​the display unit DP in the boundary area A. In the display device 10 according to the comparative example, relatively high stress may be locally applied to the display unit DP in the boundary area B between the first curved portion 61R1 and the flat portion 61F. Therefore, compared with the display device 10 according to the comparative example, it can be seen that the roller 1261 of the display device 1200 according to the present embodiment further includes the second curved portion 1261R2 and the third curved portion 1261R3, so that the stress applied to the boundary area A can be reduced by about 35%, and the stress is applied to a relatively wide area without being concentrated only in a partial area.

[0166] Therefore, in the display device 1200 according to the embodiment, the second curved portion 1261R2 and the third curved portion 1261R3 may also be formed in the boundary region A between the first curved portion 1261R1 and the flat portion 1261F to support the display unit DP, so that the display unit DP can be rolled with a large radius of curvature and stress is not concentrated in a partial region of the display unit DP. Since the second curved portion 1261R2 and the third curved portion 1261R3 support the display unit DP in the boundary region A, the stress applied to the display unit DP can be reduced, specifically, the stress applied to the partial region of the display panel 120 adjacent to the pad region can be reduced. In addition, since the stress is distributed to a wider area in the boundary region A, defects such as cracks occurring in the pad region of the display unit DP can be minimized compared to the display device 10 according to the comparative example in which the stress is concentrated in a specific region. Therefore, similar to the roller 1261 of the display device 1200 according to the embodiment, the rollers 161, 861, and 1061 of the display devices 100, 800, and 1000 according to the embodiments of the present disclosure further include one or more curved portions 161R2, 861R2, 1061R2, 861R3, 1061R3, 861R, and 1061R4 disposed between the first curved portion 1261R1 and the flat portions 161F, 861F, and 1061F. Therefore, cracks or defects caused by stress concentration in a specific area of ​​the display unit DP during the rolling process can be minimized, and the reliability of the display devices 100, 800, and 1000 can be improved.

[0167] Exemplary embodiments of the present disclosure may also be described as follows:

[0168] According to one aspect of the present disclosure, a display device is provided. The display device includes: a display unit; and a roller, the roller being configured so that the display unit is rolled around the roller or unrolled from the roller, the roller including a flat portion, a first curved portion extending from the flat portion, and a second curved portion extending from the first curved portion toward the flat portion. The radius of curvature of the first curved portion is greater than the radius of curvature of the second curved portion, and the radius of curvature of the display unit rolled around the second curved portion is greater than the radius of curvature of the second curved portion.

[0169] When the display unit is rolled, the display unit may abut only a portion of the second curved portion.

[0170] The roller may further include a third curved portion disposed between the second curved portion and the first curved portion, and a radius of curvature of the third curved portion may be smaller than a radius of curvature of the second curved portion.

[0171] The roller may include: a main roller having an outer peripheral surface including a first curved portion and a flat portion, the main roller including an opening area formed by opening a portion of the first curved portion; and a first auxiliary roller, which is arranged in the opening area and has an outer peripheral surface corresponding to the second curved portion, and the center axis of the first auxiliary roller may be coupled to two opposite ends of the main roller.

[0172] In the opening region, a portion of the first auxiliary roller may be disposed inside the main roller, and the remaining portion of the first auxiliary roller may be disposed outside the main roller and define the second curved portion.

[0173] The roller may also include a second auxiliary roller, which is configured to define a third curved portion between the first curved portion and the second curved portion, and has a central axis coupled to two opposite ends of the main roller, and in the opening area, a portion of the second auxiliary roller may be disposed inside the main roller, and the remainder of the second auxiliary roller may be disposed outside the main roller and define the third curved portion.

[0174] A shortest straight-line distance from a central axis of the first auxiliary roller to the first curved portion may be equal to a shortest straight-line distance from a central axis of the second auxiliary roller to the first curved portion.

[0175] The radius of the first auxiliary roller may be greater than the radius of the second auxiliary roller.

[0176] The display unit may include: a display panel; a first cover configured to support a rear surface of the display panel; and a bottom cover configured to support one end of the display panel and one end of the first cover, and a surface of the bottom cover may be disposed on the same plane as a tangent plane of the second curved portion.

[0177] According to another aspect of the present disclosure, a display device is provided. The display device includes: a display panel; and a roller configured so that the display panel is rolled around the roller or unrolled from the roller, the roller including: a flat portion; a first curved portion; and a second curved portion, which is disposed between the first curved portion and the flat portion and has a smaller curvature radius than the first curved portion. A portion of the second curved portion protrudes further outward than one surface of the flat portion.

[0178] The roller may further include a third curved portion disposed between the first curved portion and the second curved portion, and a curvature radius of the display panel rolled around the second and third curved portions may be greater than those of the second and third curved portions.

[0179] The second curved portion may have a greater radius of curvature than the third curved portion, and a surface area of ​​the second curved portion may be greater than a surface area of ​​the third curved portion.

[0180] The roller may include: a main roller having an outer peripheral surface including a first curved portion and a flat portion, the main roller having a plurality of coupling holes arranged at two opposite ends thereof; and a first auxiliary roller having a central axis coupled to the plurality of coupling holes, and a portion of the first auxiliary roller may be arranged outside the main roller and define a second curved portion, and the remainder of the first auxiliary roller may be arranged inside the main roller.

[0181] The roller may also include a second auxiliary roller having a central axis coupled to a plurality of coupling holes of the main roller, and a portion of the second auxiliary roller may be disposed outside the main roller and may define a third curved portion between the first curved portion and the second curved portion, and the remainder of the second auxiliary roller may be disposed inside the main roller.

[0182] The first auxiliary roller may be closer to the flat portion than the second auxiliary roller, and a radius of the first auxiliary roller may be greater than a radius of the second auxiliary roller.

[0183] The volume of a portion of the first auxiliary roller disposed outside the main roller may be greater than the volume of a portion of the second auxiliary roller disposed outside the main roller.

[0184] The shortest straight-line distances from the plurality of coupling holes to the outer circumferential surface of the main roller may be equal to each other.

[0185] The display device may further include: a plurality of flexible films connected to one end of the display panel; a printed circuit board connected to one end of the plurality of flexible films; and a bottom cover configured to support the printed circuit board and one end of the display panel in a flat state when the display panel is rolled. An imaginary plane extending from one surface of the bottom cover may abut the second curved portion.

[0186] Although the exemplary embodiments of the present disclosure have been described in detail with reference to the accompanying drawings, the present disclosure is not limited thereto and can be implemented in many different forms without departing from the technical concept of the present disclosure. Therefore, the exemplary embodiments of the present disclosure are provided for illustrative purposes only and are not intended to limit the technical concept of the present disclosure. The scope of the technical concept of the present disclosure is not limited thereto. Therefore, it should be understood that the above exemplary embodiments are exemplary in all aspects and do not limit the present disclosure. The scope of protection of the present disclosure should be understood based on the attached claims, and all technical concepts within their equivalent scope should be understood to fall within the scope of protection of the present disclosure.

Claims

1. A display device, comprising: Display unit; as well as A roller configured such that the display unit is rolled around or unrolled from the roller, the roller comprising: a main roller having an outer peripheral surface including a flat portion and a first curved portion extending from the flat portion, the main roller including an open area formed by opening a portion of the first curved portion, and a first auxiliary roller disposed in the opening region and having an outer peripheral surface corresponding to a second curved portion extending from the first curved portion toward the flat portion, wherein a central axis of the first auxiliary roller is coupled to two opposite ends of the main roller, The first curved portion has a greater curvature radius than the second curved portion, and the display unit wrapped around the second curved portion has a greater curvature radius than the second curved portion.

2. The display device according to claim 1, wherein: When the display unit is rolled, the display unit abuts only a portion of the second curved portion.

3. The display device according to claim 1, wherein: In the opening region, a portion of the first auxiliary roller is disposed inside the main roller, and the remaining portion of the first auxiliary roller is disposed outside the main roller and defines the second curved portion.

4. The display device according to claim 1, wherein: The roller further includes a second auxiliary roller configured to define a third curved portion between the first curved portion and the second curved portion and having a central axis coupled to both opposite ends of the main roller, and Wherein, in the opening area, a portion of the second auxiliary roller is disposed inside the main roller, and the remaining portion of the second auxiliary roller is disposed outside the main roller and defines the third curved portion.

5. The display device according to claim 4, wherein: The shortest straight-line distance from the center axis of the first auxiliary roller to the first curved portion is equal to the shortest straight-line distance from the center axis of the second auxiliary roller to the first curved portion.

6. The display device according to claim 5, wherein: The radius of the first auxiliary roller is greater than the radius of the second auxiliary roller.

7. The display device according to claim 4, wherein: A curvature radius of the third curved portion is smaller than a curvature radius of the second curved portion.

8. The display device according to claim 1, wherein: The display unit comprises: Display panel; a first cover configured to support a rear surface of the display panel; and a bottom cover configured to support one end of the display panel and one end of the first cover, and Wherein, one surface of the bottom cover is arranged on the same plane as a tangent plane of the second curved portion.

9. A display device, comprising: Display panel; as well as A roller configured such that the display panel is rolled around or unrolled from the roller, the roller comprising: a main roller having an outer peripheral surface including a flat portion and a first curved portion, the main roller having a plurality of coupling holes provided at both opposite ends of the main roller, and a first auxiliary roller having a central axis coupled to the plurality of coupling holes, wherein a portion of the first auxiliary roller is disposed outside the main roller and defines a second curved portion, the second curved portion is disposed between the first curved portion and the flat portion and has a smaller radius of curvature than that of the first curved portion, and a remaining portion of the first auxiliary roller is disposed inside the main roller, A portion of the second curved portion protrudes further outward than a surface of the flat portion.

10. The display device according to claim 9, wherein: The roller further includes a second auxiliary roller having a central axis coupled to the plurality of coupling holes of the main roller, and Part of the second auxiliary roller is disposed outside the main roller and defines a third curved portion between the first curved portion and the second curved portion, and the remaining part of the second auxiliary roller is disposed inside the main roller.

11. The display device according to claim 10, wherein: The first auxiliary roller is closer to the flat portion than the second auxiliary roller, and a radius of the first auxiliary roller is greater than a radius of the second auxiliary roller.

12. The display device according to claim 11, wherein: A volume of a portion of the first auxiliary roller disposed outside the main roller is greater than a volume of a portion of the second auxiliary roller disposed outside the main roller.

13. The display device according to claim 11, wherein: The shortest straight-line distances from the plurality of coupling holes to the outer peripheral surface of the main roller are equal to each other.

14. The display device according to claim 10, wherein: A curvature radius of the display panel wrapped around the second curved portion and the third curved portion is greater than a curvature radius of the second curved portion and a curvature radius of the third curved portion.

15. The display device according to claim 10, wherein: A radius of curvature of the second curved portion is greater than a radius of curvature of the third curved portion, and a surface area of ​​the second curved portion is greater than a surface area of ​​the third curved portion.

16. The display device according to claim 9, further comprising: a plurality of flexible films connected to one end of the display panel; a printed circuit board connected to one end of the plurality of flexible films; as well as a bottom cover configured to support the printed circuit board and one end of the display panel in a flat state when the display panel is rolled up, Wherein, an imaginary plane extending from one surface of the bottom cover is adjacent to the second bent portion.

17. A display device, comprising: Display panel; as well as A roller configured such that the display panel is rolled around or unrolled from the roller, the roller comprising: a main roller having an outer peripheral surface including a flat portion and a first curved portion, the main roller including an open area formed by opening a portion of the first curved portion, and a first auxiliary roller disposed in the opening area and having an outer peripheral surface corresponding to a second curved portion, the second curved portion being disposed between the first curved portion and the flat portion and having a curvature radius smaller than that of the first curved portion, wherein a central axis of the first auxiliary roller is coupled to two opposite ends of the main roller; a plurality of flexible films connected to one end of the display panel; a printed circuit board connected to one end of the plurality of flexible films; and a bottom cover configured to be rolled up on a flat portion of the roller in a flat state when the display panel is rolled up to support the printed circuit board and one end of the display panel, A portion of the second curved portion protrudes further outward than a surface of the flat portion, so that a curvature radius of the display panel wrapped around the second curved portion is greater than a curvature radius of the second curved portion.

Images