Stretchable display device

Abstract

A stretchable display device includes a first substrate having a display area thereon and a non-display area adjacent to the display area. The retractable display device includes a plurality of rigid portions disposed in a display area on a first substrate and spaced apart from each other in a first direction and a second direction. The retractable display device includes a flexible portion disposed between adjacent rigid portions in a first direction or a second direction. The stretchable display device includes a second substrate disposed over the first substrate. A length of the flexible portion is smaller than a length of the rigid portion in one direction. The rigid portion and the flexible portion rotate at a rotation angle relative to the first direction and the second direction.

Description

Technical Field

[0001] The present disclosure relates to a display device, and more particularly, to a stretchable display device having a high resolution. Background Art

[0002] As the information society has advanced, interest in displays for processing and displaying a large amount of information has increased, and various types of displays have been developed.

[0003] Accordingly, in addition to well-known rectangular displays, flexible display devices such as bendable display devices for gaming, foldable display devices capable of being folded and unfolded, and rollable display devices having optimal space utilization have been widely developed.

[0004] Recently, a stretchable display device that is more flexible than these flexible display devices has been attracting attention as a next-generation display. Summary of the Invention

[0005] A stretchable display device is a display that can freely change the shape of the screen without distortion even when the size of the screen increases, folds, or twists. Different from bendable, foldable, or rollable display devices that can only be transformed in specific areas or directions, a stretchable display device can achieve an ultimate free form and is considered the most suitable display device for the era of the Internet of Things (IoT), 5G, and autonomous vehicles.

[0006] A stretchable display device may include a rigid part provided with pixels and a flexible part provided with connection lines connecting the pixels. The rigid part may not be stretched, while the flexible part may be stretched.

[0007] Therefore, in order to ensure stretchability and repeated stretch reliability, sufficient space is required for the flexible part, which limits the increase in the resolution of the stretchable display device.

[0008] Accordingly, the present disclosure provides a stretchable display device that substantially eliminates one or more limitations and disadvantages described above and related to the background art.

[0009] More specifically, an object of the present invention is to provide a stretchable display device having a high resolution.

[0010] Additional features and aspects will be set forth in the description below, and in part will be apparent from the description, or may be learned by practice of the present disclosure provided herein. Other features and aspects of the inventive concept may be realized and obtained by means of the structures particularly pointed out in the written description, or may be derived therefrom, as well as the claims and the drawings.

[0011] To achieve these and other aspects of the present disclosure, as embodied and broadly described herein, a stretchable display device includes a first substrate including a display area and a non-display area; a plurality of rigid portions disposed in the display area on the first substrate and spaced apart from each other in a first direction and a second direction; flexible portions disposed between adjacent rigid portions in the first direction or the second direction; and a second substrate disposed on the first substrate, wherein the length of the flexible portion is less than the length of the rigid portion in one direction, and wherein the rigid portion and the flexible portion are rotated by a certain rotation angle with respect to the first direction and the second direction.

[0012] It should be understood that the foregoing general description and the following detailed description are both exemplary and are intended to provide further explanation of the inventive concept claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings included to provide a further understanding of the present disclosure and incorporated in and constituting a part of this application illustrate aspects of the present disclosure and, together with the description, serve to explain the various principles of the present disclosure.

[0014] In the drawings:

[0015] Figure 1 is a schematic plan view of a stretchable display device according to an embodiment of the present disclosure;

[0016] Figure 2 is a plan view schematically showing a part of a stretchable display device according to an embodiment of the present disclosure;

[0017] Figure 3A and Figure 3B is a plan view schematically showing a part of another example of a stretchable display device according to an embodiment of the present disclosure;

[0018] Figure 4 is an equivalent circuit diagram of a sub-pixel of a stretchable display device according to an embodiment of the present disclosure;

[0019] Figure 5 is corresponding to Figure 2 a cross-sectional view taken along line I-I';

[0020] Figure 6 is a schematic plan view of a flexible portion of a stretchable display device according to an embodiment of the present disclosure;

[0021] Figure 7A is a schematic plan view showing the structure of a stretchable line according to an embodiment of the present disclosure;

[0022] Figure 7Bis a schematic plan view showing the structure of a stretchable wire according to a first comparative example;

[0023] Figure 7C is a schematic plan view showing the structure of a stretchable wire according to a second comparative example;

[0024] Figure 8 is a graph showing the repeated stretch reliability of stretchable wires according to embodiments and comparative examples of the present disclosure;

[0025] Figure 9 is a schematic plan view of a stretchable display device according to a comparative example;

[0026] Figure 10 is a schematic plan view of another arrangement structure of a stretchable display device according to an embodiment of the present disclosure;

[0027] Figure 11A and Figure 11B is a plan view of other arrangement structures of a stretchable display device according to an embodiment of the present disclosure;

[0028] Figure 12 is a schematic plan view of a non-rotated rigid portion and a flexible portion according to an embodiment of the present disclosure;

[0029] Figure 13 is a schematic plan view of a rotated rigid portion and a flexible portion according to an embodiment of the present disclosure; and

[0030] Figure 14 is a schematic cross-sectional view of a stretchable display device according to another embodiment of the present disclosure. DETAILED DESCRIPTION

[0031] Advantages and features of the present disclosure and methods for realizing them will become clear from the embodiments described in detail below with reference to the accompanying drawings. However, the present disclosure can be implemented in many different forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art to which the present disclosure pertains.

[0032] The shapes, sizes, dimensions (e.g., length, width, height, thickness, radius, diameter, area, etc.), ratios, angles, quantities, number of elements, etc. disclosed in the drawings for describing the embodiments of the present disclosure are merely examples, and thus the present disclosure is not limited to what is illustrated.

[0033] For ease of description, dimensions including the dimensions and thicknesses of each component shown in the drawings are illustrated, and the present disclosure is not limited to the dimensions and thicknesses of the components shown, but it should be noted that the relative dimensions including the relative dimensions, positions, and thicknesses of the components shown in the various drawings submitted herein are part of the present disclosure.

[0034] Throughout the specification, the same reference numerals denote the same components. Additionally, in the following description of the present disclosure, when it is determined that a detailed description of known related art is not necessary to obscure the gist of the present disclosure, its detailed description will be omitted herein or may be briefly discussed.

[0035] When terms such as "comprising", "having", "including" mentioned in the present disclosure are used, other parts may be added, unless the term "only" is used herein. Additionally, when a component is expressed in the singular, it includes the plural, unless otherwise specified.

[0036] When analyzing a component, the error range is construed to be included even if not explicitly described.

[0037] As used herein, the text "and / or" indicates that one or both of the options may be considered. For example, "A and / or B" means (1) option A, or (2) option B, or (3) both option A and option B.

[0038] When describing positional relationships, for example, when the positional relationship between two parts / layers is described as "above", "on", "upon", "below", "beneath", "next to", etc., one or more other parts / layers may be provided between the two parts / layers, unless the terms "immediately" or "directly" are used in conjunction therewith.

[0039] When describing temporal relationships, for example, when a temporal precedence relationship is described as "after", "subsequent to", "posterior to", "prior to", etc., cases that are not continuous or sequential may also be included, unless "immediately" or "directly" is used.

[0040] When the first element is referred to as "connected or coupled to", "in contact with or overlapping" etc. the second element, it should be understood that not only can the first element be "directly connected or coupled to" or "directly in contact with or overlapping" the second element, but also a third element can be "interposed" between the first element and the second element, or the first element and the second element can be "connected or coupled", "in contact with or overlapping" etc. with each other via a fourth element. Here, the second element may include at least one of two or more elements that are "connected or coupled", "in contact with or overlapping" etc. with each other.

[0041] Although terms such as first and second are used to describe various components, these components are not substantially limited by these terms. These terms are only used to distinguish one component from another and may not define any order or sequence. Thus, the first component described below may essentially be the second component within the technical spirit of the present disclosure.

[0042] The features of various embodiments of the present disclosure may be partially or fully combined or integrated with each other, various interlocks and drives are possible technically, and each embodiment may be implemented independently of each other or in a related relationship together.

[0043] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0044] Figure 1 is a schematic plan view of a stretchable display device according to an embodiment of the present disclosure.

[0045] In Figure 1 , a stretchable display device according to an embodiment of the present disclosure may include a display panel 100, a printed circuit board 190, and a flexible printed circuit 192.

[0046] The display panel 100 may be stretched in a first direction (X-axis direction) and / or a second direction (Y-axis direction) that intersects (e.g., is perpendicular to) the first direction. The display panel 100 may include a display area DA for displaying an image and a non-display area NDA provided on at least one side of the display area DA and adjacent to at least one side of the display area DA.

[0047] A rigid portion A1 corresponding to the first region and a flexible portion A2 corresponding to the second region may be provided in the display area DA, and a pad portion A3 corresponding to the third region may be provided in the non-display area NDA.

[0048] The rigid portion A1 may be provided in an island form and may be arranged to be spaced apart from another rigid portion A1 along the first direction X and the second direction Y. Figure 1 Shows a plurality of rigid portions A1 arranged on the display panel 100 and spaced apart from each other like islands. The rigid portion A1 may be, for example, polygonal. In some embodiments, the rigid portion A1 may have a substantially rectangular shape. Pixels including a plurality of sub-pixels may be provided in the rigid portion A1. Each of the plurality of sub-pixels may include a light-emitting diode, at least one thin-film transistor, a plurality of lines, and a plurality of electrodes.

[0049] The flexible portion A2 can be disposed between the rigid portions A1 adjacent to each other in each of the first direction X and the second direction Y. A plurality of flexible portions A2 can be disposed between adjacent rigid portions A1. Additionally, the flexible portion A2 can be disposed between the rigid portion A1 and the pad portion A3 (i.e., the pad portion A32) adjacent to each other in the first direction X and between the rigid portion A1 and the pad portion A3 (i.e., the pad portion A31) adjacent to each other in the second direction Y. The term "flexible" in the flexible portion means that the flexible portion A2 is stretchable, extensible, flexible, bendable, pliable, etc. On the other hand, the term "rigid" in the rigid portion means that the stretchability, elongation, flexibility, bendability, pliability, etc. of the rigid portion A1 are smaller compared to the flexible portion. For example, the rigid portion can also be stretchable to a certain extent, but not as stretchable as the flexible portion.

[0050] A stretchable line serving as a connection line connecting adjacent pixels can be disposed in the flexible portion A2. The stretchable line can include a plurality of signal lines, such as a gate line, a data line, a high potential line, a low potential line, an emission line, and a reference voltage line. The stretchable line is disposed in each flexible portion A2. Refer Figure 1 , there are a plurality of stretchable lines connecting adjacent rigid portions A1. There are also a plurality of stretchable lines connecting the rigid portion A1 to the pad portion A3. For example, Figure 1 The plurality of stretchable lines shown include a first group FGSL of stretchable lines connected between adjacent rigid portions A1 and a second group SGSL of stretchable lines connected between the pad portion A3 and the rigid portion A1. Figure 1 There are two types of the pad portion A3 shown. The first group FGPP of the pad portion A32 is rectangular in a top view, and the second group SGPP of the pad portion A31 is serrated in a top view. Here, one group of stretchable lines connects the second group SGPP of the pad portion A31 to the adjacent rigid portion A1, and another group of stretchable lines connects the first group FGPP of the pad portion A32 to the adjacent rigid portion A1.

[0051] The flexible portion A2 can have at least one bent portion. The flexible portion A2 can have a bent shape and have a substantially S-shaped shape. Therefore, the stretchable line can also have a bent shape and have a substantially S-shaped shape.

[0052] Meanwhile, the non-display area NDA can be an area where no image is displayed, and the pad portion A3 can be disposed in the non-display area NDA. A plurality of link lines extending from a plurality of signal lines disposed in the display area DA and a plurality of pads connected to the ends of the plurality of link lines can be disposed in the pad portion A3.

[0053] The pad portion A3 may include a first pad portion A31 and a second pad portion A32. The first pad portion A31 may correspond to the rigid portion A1 disposed along the first direction X, and the second pad portion A32 may correspond to the rigid portion A1 disposed along the second direction Y. The first pad portion A31 may be disposed on at least one of the upper and lower sides of the display area DA, and the second pad portion A32 may be disposed on at least one of the left and right sides of the display area DA. For example, as Figure 1 shown, the first pad portion A31 may be disposed on the upper side of the display area DA, and the second pad portion A32 may be disposed on the left side of the display area DA.

[0054] The first pad portion A31 may be set as one pattern corresponding to a plurality of rigid portions A1 disposed along the first direction X. That is, one first pad portion A31 may correspond to a plurality of rigid portions A1.

[0055] On the other hand, the second pad portion A32 may be separated to correspond to each of a plurality of rigid portions A1 disposed along the second direction Y. That is, a plurality of second pad portions A32 may respectively correspond to a plurality of rigid portions A1.

[0056] However, the embodiments of the present disclosure are not limited thereto. In other embodiments, the first pad portion A31 may be separated to correspond to each of a plurality of rigid portions A1 disposed along the first direction X, and the second pad portion A32 may be set as one pattern corresponding to a plurality of rigid portions A1 disposed along the second direction Y.

[0057] In some embodiments, the rigid portion A1 and the pad portion A3 may not be stretched, while the flexible portion A2 may be stretched.

[0058] Meanwhile, the flexible printed circuit 192 may be connected to the first pad portion A31 of the pad portion A3. The flexible printed circuit 192 may include a base film made of a flexible material and a driver integrated circuit chip (driver IC chip) mounted on the base film. The flexible printed circuit 192 may generate a gate signal and a data signal for displaying an image and send the gate signal and the data signal to the display panel 100.

[0059] In Figure 1 the embodiment, the flexible printed circuit 192 is shown as a chip on film (COF) type, but the embodiments of the present disclosure are not limited thereto. In other embodiments, the flexible printed circuit 192 may be a chip on glass (COG) type or a tape carrier package (TCP) type.

[0060] The printed circuit board 190 may include a circuit portion for controlling the driver IC chip. For example, the printed circuit board 190 may include a timing controller that receives an image signal and a plurality of timing signals, generates a plurality of control signals, and transmits the generated control signals to the driver IC chip.

[0061] In the stretchable display device according to an embodiment of the present disclosure, the rigid portion A1 and the flexible portion A2 may be arranged to rotate with respect to the first direction X and the second direction Y. Accordingly, similar to the rigid portion A1 and the flexible portion A2, the second pad portion A32 may also be arranged to rotate with respect to the first direction X and the second direction Y.

[0062] Meanwhile, the first pad portion A31 may have an inclination with respect to the first direction X on the side facing the display area DA to correspond to each rigid portion A1. Accordingly, the side of the first pad portion A31 facing the display area DA may have a prism shape or a serrated shape.

[0063] As described above, in the stretchable display device according to an embodiment of the present disclosure, the stretchable line may have a substantially S-shaped configuration, and the rigid portion A1 and the flexible portion A2 may be arranged to be rotated, thereby enabling a relatively high resolution. For example, the resolution of the stretchable display device according to an embodiment of the present disclosure may be 150 PPI or higher, which will be described in detail later.

[0064] Figure 2 is a plan view schematically showing a part of a stretchable display device according to an embodiment of the present disclosure, and Figure 3A and Figure 3B is a plan view schematically showing a part of another example of a stretchable display device according to an embodiment of the present disclosure.

[0065] In Figure 2 , Figure 3A and Figure 3B the rigid portion A1 and the flexible portion A2 may rotate clockwise by a selected angle "θ" with respect to the first direction X and the second direction Y. It can also be said that the rigid portion A1 and the flexible portion A2 may rotate clockwise by a selected angle "θ" with respect to the first direction X and the second direction Y of the display panel 100.

[0066] At this time, as Figure 2As shown, the multiple sub-pixels SP1, SP2, and SP3 provided in each rigid portion A1 can also be rotated. For example, a first sub-pixel SP1, a second sub-pixel SP2, and a third sub-pixel SP3 can be provided in each rigid portion A1, and the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 can be rotated in the same direction as the rigid portion A1 at the same or substantially the same angle. In this case, the configuration of the lines and electrodes provided in each rigid portion A1 can be the same as or substantially the same as before. However, various embodiments are not limited thereto, and the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 can be rotated at an angle different from that of the rigid portion A1.

[0067] In addition, as Figure 2 shown, each of the multiple sub-pixels has a first side LS (which can also be referred to as the long side LS because the drawing shows that it is longer than the side adjacent to the long side) and a second side SS (which can also be referred to as the short side SS because the drawing shows that it is shorter than the long side adjacent to the short side). For example, the long side LS of the first sub-pixel SP1 can be rotated with respect to the second direction (e.g., the y-axis direction) of the display panel 100.

[0068] Alternatively, as Figure 3A shown, the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 may not be rotated. Therefore, the long sides of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 can be parallel to the second direction Y. In this case, light-emitting diodes are provided in the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 of each rigid portion A1. In other embodiments, as Figure 3B shown, some of the sub-pixels on the rigid portion A1 can be rotated, while other sub-pixels on the rigid portion A1 can be not rotated. For example, even if the rigid portion AY1 is rotated at a selected angle "θ", the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 on the rigid portion AY1 may not be rotated at the selected angle "θ". Therefore, the long sides of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 on the rigid portion AY1 can be parallel to the second direction Y. On the other hand, the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 on the rigid portion AY2 can be rotated at the selected angle "θ". Therefore, the long sides of the first sub-pixel SP1, the second sub-pixel SP2, and the third sub-pixel SP3 on the rigid portion AY2 may not be aligned with the Y axis. That is, the sub-pixels on the rigid portion AY2 can be inclined at the selected angle "θ".

[0069] Figure 4 is an equivalent circuit diagram of a sub-pixel of a stretchable display device according to an embodiment of the present disclosure.

[0070] InFigure 4 In Figure 4 , each of a sub-pixel of a stretchable display device according to an embodiment of the present disclosure, that is, each of a first sub-pixel SP1, a second sub-pixel SP2, and a third sub-pixel SP3 may include a driving transistor DT, a first transistor T1, a second transistor T2, a third transistor T3, a fourth transistor T4, a fifth transistor T5, a storage capacitor Cst, and a light-emitting diode LED.

[0071] For example, the driving transistor DT, the first transistor T1, the second transistor T2, the third transistor T3, the fourth transistor T4, and the fifth transistor T5 may be P-type transistors. However, the embodiments of the present disclosure are not limited thereto. In other embodiments, the driving transistor DT, the first transistor T1, the second transistor T2, the third transistor T3, the fourth transistor T4, and the fifth transistor T5 may be N-type transistors.

[0072] The driving transistor DT may be switched according to the voltage of a first capacitor electrode of the storage capacitor Cst, and may be connected to a high potential voltage ELVDD. Specifically, the gate of the driving transistor DT may be connected to the first capacitor electrode of the storage capacitor Cst and the source of the second transistor T2. The source of the driving transistor DT may be connected to the high potential voltage ELVDD. The drain of the driving transistor DT may be connected to the drain of the second transistor T2 and the source of the fourth transistor T4.

[0073] The first transistor T1 may be switched according to a gate signal SCAN, and may be connected to a data signal Vdata. Specifically, the gate of the first transistor T1 may be connected to the gate signal SCAN. The source of the first transistor T1 may be connected to the data signal Vdata. The drain of the first transistor T1 may be connected to a second capacitor electrode of the storage capacitor Cst and the source of the third transistor T3.

[0074] The second transistor T2 may be switched according to the gate signal SCAN, and may be connected to the driving transistor DT. Specifically, the gate of the second transistor T2 may be connected to the gate signal SCAN. The source of the second transistor T2 may be connected to the first capacitor electrode of the storage capacitor Cst and the gate of the driving transistor DT. The drain of the second transistor T2 may be connected to the source of the driving transistor DT and the source of the fourth transistor T4.

[0075] The third transistor T3 may be switched according to a light-emitting signal EM, and may be connected to a reference voltage Vref. The gate of the third transistor T3 may be connected to the light-emitting signal EM. The source of the third transistor T3 may be connected to the second capacitor electrode of the storage capacitor Cst and the drain of the first transistor T1. The drain of the third transistor T3 may be connected to the reference voltage Vref and the source of the fifth transistor T5.

[0076] The fourth transistor T4 can be switched according to the emission signal EM and can be connected to the driving transistor DT and the light-emitting diode LED. Specifically, the gate of the fourth transistor T4 can be connected to the emission signal EM. The source of the fourth transistor T4 can be connected to the drain of the driving transistor DT and the drain of the second transistor T2. The drain of the fourth transistor T4 can be connected to the drain of the fifth transistor T5 and the first electrode of the light-emitting diode LED.

[0077] The fifth transistor T5 can be switched according to the strobe signal SCAN and can be connected to the reference voltage Vref and the fourth transistor T4. Specifically, the gate of the fifth transistor T5 can be connected to the strobe signal SCAN. The source of the fifth transistor T5 can be connected to the reference voltage Vref and the drain of the third transistor T3. The drain of the fifth transistor T5 can be connected to the drain of the fourth transistor T4 and the first electrode of the light-emitting diode LED.

[0078] The storage capacitor Cst can store the data signal Vdata and the threshold voltage Vth of the driving transistor DT. The first capacitor electrode of the storage capacitor Cst can be connected to the gate of the driving transistor DT and the source of the second transistor T2. The second capacitor electrode of the storage capacitor Cst can be connected to the drain of the first transistor T1 and the source of the third transistor T3.

[0079] The light-emitting diode LED can be connected between the fourth transistor T4 and the fifth transistor T5 and the low-potential voltage ELVSS and can emit light with a brightness proportional to the current of the driving transistor DT. The first electrode of the light-emitting diode LED as the anode can be connected to the drain of the fourth transistor T4 and the drain of the fifth transistor T5. The second electrode of the light-emitting diode LED as the cathode can be connected to the low-potential voltage ELVSS.

[0080] In Figure 4 an embodiment of the present disclosure, by way of example, each sub-pixel has a 6T1C structure including six transistors and one capacitor, but in other embodiments, each sub-pixel can have one of 2T1C, 4T1C, 5T1C, 3T2C, 4T2C, 5T2C, 6T2C, 7T1C, 7T2C, 8T1C, and 8T2C structures.

[0081] Figure 5 is a cross-sectional view corresponding to Figure 2 the line I-I'. Figure 5 shows a cross-section of a sub-pixel corresponding to a stretchable display device according to an embodiment of the present disclosure and will be described with reference to Figures 1 to 4 together.

[0082] In Figure 5Among them, the stretchable display device according to an embodiment of the present disclosure may include a first substrate 101 and a second substrate 106 that face each other and are spaced apart.

[0083] The first substrate 101 and the second substrate 106, which are flexible substrates, may be formed of a soft substance or a soft material having bending or stretching properties. For example, the first substrate 101 and the second substrate 106 may be formed of a silicone rubber such as polydimethylsiloxane (PDMS), an elastomer such as polyurethane (PU), or a styrene-butadiene block copolymer such as styrene-butadiene-styrene (SBS).

[0084] The first substrate 101 and the second substrate 106 may be formed of the same material. However, the embodiments of the present disclosure are not limited thereto. In other embodiments, the first substrate 101 and the second substrate 106 may be formed of different materials.

[0085] The first substrate 101 and the second substrate 106 may have a relatively low elastic modulus, i.e., Young's modulus, and may have a relatively high ductile fracture rate. Here, the elastic modulus is a value representing the deformation rate relative to the stress applied to an object. If the elastic modulus is relatively high, the hardness may be relatively high. In addition, the ductile fracture rate refers to the elongation rate at the time when a stretched object breaks or ruptures. For further detailed explanation, the ductile fracture rate refers to the extension distance when the stretched object breaks or ruptures. That is, the ductile fracture rate is defined as the percentage of the length of the original object to the length of the stretched object when the object has been sufficiently stretched to be considered broken. For example, if the length of an object (e.g., a substrate) is 100 cm when the object is not stretched, and then, when the object is stretched to be sufficient to break or rupture at that length, it reaches a length of 110 cm, then it has been stretched to 110% of its original length. In this case, the ductile fracture rate of the object is 110%. Therefore, this number can also be called the ductile fracture ratio because it is the ratio of the stretched length as the numerator to the original unstretched length as the denominator when fracture occurs.

[0086] For example, each of the first substrate 101 and the second substrate 106 may have an elastic modulus of several MPa to several hundred MPa and a ductile fracture rate of about 100% or more. In addition, each of the first substrate 101 and the second substrate 106 may have a thickness of about 10 μm to about 1 mm. However, the embodiments of the present disclosure are not limited thereto.

[0087] A rigid portion A1 corresponding to the first region, a flexible portion A2 corresponding to the second region, and a pad portion A3 corresponding to the third region may be provided on the first substrate 101 and the second substrate 106.

[0088] The first adhesive layer 102 may be disposed on the inner surface of the first substrate 101, and the base substrate 104 may be disposed on the first adhesive layer 102.

[0089] The first adhesive layer 102 may bond the first substrate 101 and the base substrate 104. The first adhesive layer 102 may be formed of an acryloyl-based, silicone-based, or urethane-based adhesive. For example, the first adhesive layer 102 may be an optically clear adhesive (OCA) formed and attached in the form of a film, or an optically clear resin (OCR) cured after applying a liquid material.

[0090] The base substrate 104 may include a first base portion 104a, a second base portion 104b, and a third base portion 104c. The first base portion 104a may be disposed to correspond to the rigid portion A1, the second base portion 104b may be disposed to correspond to the flexible portion A2, and the third base portion 104c may be disposed to correspond to the pad portion A3.

[0091] The first base portion 104a may be disposed in a plate shape in the display area DA and may be a component for supporting and protecting the plurality of sub-pixels SP1, SP2, and SP3. The first base portions 104a may be plural, and the plural first base portions 104a may be spaced apart from each other in the first direction X and the second direction Y.

[0092] The second base portion 104b may be disposed between the first base portion 104a and the third base portion 104c. Additionally, the second base portion 104b may be disposed between the adjacent first base portions 104a in the display area DA.

[0093] The second base portion 104b may include at least one curved portion and may be used to support and protect the stretchable wire 166.

[0094] The third base portion 104c may be disposed in a plate shape in the non-display area NDA, and the pads 136 and 159 connected to the flexible printed circuit 192 may be disposed on the third base portion 104c.

[0095] The adjacent first base portion 104a, second base portion 104b, and third base portion 104c may be connected and disposed integrally.

[0096] The base substrate 104 may be formed of a rigid material having a lower flexibility than the flexibility of the first substrate 101. For example, the base substrate 104 may be formed of a polyimide (PI) resin or an epoxy resin.

[0097] The base substrate 104 may have a relatively high elastic modulus, and the elastic modulus of the base substrate 104 may be higher than the elastic modulus of the first substrate 101. For example, the elastic modulus of the base substrate 104 may be more than 1000 times higher than the elastic modulus of the first substrate 101, but the embodiments of the present disclosure are not limited thereto.

[0098] A first buffer layer 110 may be provided on the base substrate 104. The first buffer layer 110 may block the penetration of moisture or oxygen from the outside to protect the components of the plurality of sub-pixels SP1, SP2, and SP3.

[0099] The first buffer layer 110 may be formed of a single layer or multiple layers of inorganic insulating materials. The inorganic insulating materials of the first buffer layer 110 may include silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON).

[0100] To prevent or reduce damage to the first buffer layer 110 (such as cracks caused by stretching), the first buffer layer 110 may be removed in the flexible portion A2 to substantially correspond to the rigid portion A1 and the pad portion A3, and the first buffer layer 110 may be provided on the first base 104a and the third base 104c of the base substrate 104. Meanwhile, to control the thickness and hardness of the flexible portion A2, the first buffer layer 110 may be partially provided with a relatively thin thickness on the second base 104b.

[0101] In other embodiments, the first buffer layer 110 may be omitted.

[0102] A light-blocking layer 112 may be provided on the first buffer layer 110 of the rigid portion A1. The light-blocking layer 112 may be formed of a conductive material such as a metal. For example, the light-blocking layer 112 may be formed of at least one of aluminum (Al), copper (Cu), molybdenum (Mo), titanium (Ti), chromium (Cr), nickel (Ni), tungsten (W), or an alloy thereof. The light-blocking layer 112 may have a single-layer structure or a multi-layer structure.

[0103] A second buffer layer 120 may be provided on the light-blocking layer 112 of the rigid portion A1. The second buffer layer 120 may be formed of a single layer or multiple layers of inorganic insulating materials. The inorganic insulating materials of the second buffer layer 120 may include silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON).

[0104] In addition, the second buffer layer 120 may be provided on the first buffer layer 110 of the pad portion A3 and may not be provided in the flexible portion A2.

[0105] A semiconductor layer 122 may be provided on the second buffer layer 120 of the rigid portion A1. The semiconductor layer 122 may overlap with the light-blocking layer 112, and the light-blocking layer 112 may block the light incident on the semiconductor layer 122 and prevent or reduce the deterioration of the semiconductor layer 122 due to light.

[0106] The semiconductor layer 122 may include a channel region in its central portion and source and drain regions on both sides of the channel region.

[0107] The semiconductor layer 122 can be formed of an oxide semiconductor material. Alternatively, the semiconductor layer 122 can be formed of polysilicon, and in this case, both ends of the semiconductor layer 122 can be doped with impurities.

[0108] The gate insulating layer 130 can be disposed on the semiconductor layer 122 of the rigid portion A1. The gate insulating layer 130 can be formed as a single layer or a multilayer of inorganic insulating materials. The inorganic insulating material of the gate insulating layer 130 can include silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON).

[0109] In addition, the gate insulating layer 130 can be disposed on the second buffer layer 120 of the pad portion A3 and may not be disposed in the flexible portion A2.

[0110] The gate electrode 132 and the first pad 134 can be disposed on the gate insulating layer 130 of the rigid portion A1.

[0111] The gate electrode 132 can overlap with the semiconductor layer 122 and can be disposed corresponding to the central portion of the semiconductor layer 122. Therefore, the gate electrode 132 can also overlap with the light blocking layer 112.

[0112] The first pad 134 can be spaced apart from the semiconductor layer 122 and the light blocking layer 112.

[0113] In addition, the source pad 136 can be disposed on the gate insulating layer 130 of the pad portion A3.

[0114] The gate electrode 132, the first pad 134, and the source pad 136 can be formed of a conductive material such as a metal. For example, the gate electrode 132, the first pad 134, and the source pad 136 can be formed of at least one of aluminum (Al), copper (Cu), molybdenum (Mo), titanium (Ti), chromium (Cr), nickel (Ni), tungsten (W), or an alloy thereof. The gate electrode 132, the first pad 134, and the source pad 136 can have a single-layer structure or a multilayer structure.

[0115] The first interlayer insulating layer 140 can be disposed on the gate electrode 132 and the first pad 134 of the rigid portion A1. In the rigid portion A1, the first interlayer insulating layer 140 can cover and contact at least one side surface of the first buffer layer 110, the second buffer layer 120, and the gate insulating layer 130.

[0116] The first interlayer insulating layer 140 can be formed as a single layer or a multilayer of inorganic insulating materials. The inorganic insulating material of the first interlayer insulating layer 140 can include silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON).

[0117] In addition, the first interlayer insulating layer 140 may be disposed on the source pad 136 of the pad portion A3 and may not be disposed in the flexible portion A2. In the pad portion A3, the first interlayer insulating layer 140 may cover and contact at least one side surface of the first buffer layer 110, the second buffer layer 120, and the gate insulating layer 130.

[0118] The auxiliary electrode 142 may be disposed on the first interlayer insulating layer 140 of the rigid portion A1. The auxiliary electrode 142 may overlap with the light blocking layer 112 and may contact the light blocking layer 112 through a contact hole provided in the second buffer layer 120, the gate insulating layer 130, and the first interlayer insulating layer 140. The auxiliary electrode 142 may be spaced apart from the semiconductor layer 122, the gate electrode 132, and the first pad 134.

[0119] The auxiliary electrode 142 may be formed of a conductive material such as metal. For example, the auxiliary electrode 142 may be formed of at least one of aluminum (Al), copper (Cu), molybdenum (Mo), titanium (Ti), chromium (Cr), nickel (Ni), tungsten (W), or an alloy thereof. The auxiliary electrode 142 may have a single-layer structure or a multi-layer structure.

[0120] The second interlayer insulating layer 150 may be disposed on the auxiliary electrode 142 of the rigid portion A1. The second interlayer insulating layer 150 may be formed of a single-layer or multi-layer inorganic insulating material. The inorganic insulating material of the second interlayer insulating layer 150 may include silicon nitride (SiNx), silicon oxide (SiOx), or silicon oxynitride (SiON).

[0121] In addition, the second interlayer insulating layer 150 may be disposed on the first interlayer insulating layer 140 of the pad portion A3 and may not be disposed in the flexible portion A2.

[0122] The source electrode 152, the drain electrode 154, the connection electrode 156, and the second pad 158 may be disposed on the second interlayer insulating layer 150 of the rigid portion A1.

[0123] The source electrode 152 and the drain electrode 154 may be spaced apart from each other, the gate electrode 132 is located between the source electrode 152 and the drain electrode 154, and may contact both ends of the semiconductor layer 122 through contact holes provided in the first interlayer insulating layer 140, the second interlayer insulating layer 150, and the gate insulating layer 130. In addition, the source electrode 152 may overlap with the auxiliary electrode 142 and may contact the auxiliary electrode 142 through a contact hole provided in the second interlayer insulating layer 150.

[0124] The semiconductor layer 122, the gate electrode 132, the source electrode 152, and the drain electrode 154 may constitute a thin film transistor TR.

[0125] The connection electrode 156 may be spaced apart from the thin film transistor TR. The connection electrode 156 may overlap with the first pad 134 and may be in contact with the first pad 134 through contact holes provided in the first interlayer insulating layer 140 and the second interlayer insulating layer 150.

[0126] The second pad 158 may be spaced apart from the thin film transistor TR and may be disposed adjacent to the edge of the rigid portion A1.

[0127] The auxiliary pad 159 may be provided on the second interlayer insulating layer 150 of the pad portion A3. The auxiliary pad 159 may overlap with the source pad 136 and may be in contact with the source pad 136 through contact holes provided in the first interlayer insulating layer 140 and the second interlayer insulating layer 150.

[0128] The source electrode 152, the drain electrode 154, the connection electrode 156, the second pad 158, and the auxiliary pad 159 may be formed of a conductive material such as metal. For example, the source electrode 152, the drain electrode 154, the connection electrode 156, the second pad 158, and the auxiliary pad 159 may be formed of at least one of aluminum (Al), copper (Cu), molybdenum (Mo), titanium (Ti), chromium (Cr), nickel (Ni), tungsten (W), or an alloy thereof. The source electrode 152, the drain electrode 154, the connection electrode 156, the second pad 158, and the auxiliary pad 159 may have a single-layer structure or a multi-layer structure.

[0129] A planarization layer 160 may be provided on the source electrode 152, the drain electrode 154, the connection electrode 156, and the second pad 158 of the rigid portion A1. The planarization layer 160 may eliminate the step difference caused by the underlying layers and may have a substantially flat top surface. The planarization layer 160 may be formed of an organic insulating material such as photosensitive acrylic polymer (photoacrylic).

[0130] In addition, the planarization layer 160 may be provided on the second interlayer insulating layer 150 of the pad portion A3 and may not be provided in the flexible portion A2. In the pad portion A3, the planarization layer 160 may expose the auxiliary pad 159 without covering it and may be spaced apart from the auxiliary pad 159. At this time, the planarization layer 160 may also expose the top surface of the second interlayer insulating layer 150 in the pad portion A3.

[0131] The first contact electrode 162, the second contact electrode 164, and the stretchable wire 166 may be provided on the planarization layer 160 of the rigid portion A1.

[0132] The first contact electrode 162, the second contact electrode 164, and the stretchable wire 166 may be formed of a conductive material such as a metal. For example, the first contact electrode 162, the second contact electrode 164, and the stretchable wire 166 may be formed of at least one of aluminum (Al), copper (Cu), molybdenum (Mo), titanium (Ti), chromium (Cr), nickel (Ni), tungsten (W), or an alloy thereof. The first contact electrode 162, the second contact electrode 164, and the stretchable wire 166 may have a single-layer structure or a multi-layer structure.

[0133] The first contact electrode 162 may overlap with the drain electrode 154 and may contact the drain electrode 154 through a contact hole provided in the planarization layer 160. The second contact electrode 164 may overlap with the connection electrode 156 and may contact the connection electrode 156 through a contact hole provided in the planarization layer 160.

[0134] The stretchable wire 166 may overlap with the second pad 158 and may contact the second pad 158 through a contact hole provided in the planarization layer 160.

[0135] The stretchable wire 166 may extend into and be provided in the flexible portion A2 and the pad portion A3. At this time, the stretchable wire 166 may contact the top surface and the side surface of the planarization layer 160 in the rigid portion A1 and the pad portion A3.

[0136] In the flexible portion A2, the stretchable wire 166 may contact the first buffer layer 110. Alternatively, when the first buffer layer 110 is completely removed in the flexible portion A2, the stretchable wire 166 may contact the base substrate 104.

[0137] In the pad portion A3, the stretchable wire 166 may overlap with and cover the auxiliary pad 159. Accordingly, the stretchable wire 166 may contact the top surface and the side surface of the auxiliary pad 159. In addition, in the pad portion A3, the stretchable wire 166 may contact the top surface of the second interlayer insulating layer 150.

[0138] Meanwhile, although not shown in the figure, a dam layer may be further provided on the first contact electrode 162, the second contact electrode 164, and the stretchable wire 166 in the rigid portion A1. The dam layer may expose at least a part of the first contact electrode 162 and the second contact electrode 164 and may cover the stretchable wire 166.

[0139] An adhesive layer 170 may be provided on the first contact electrode 162 and the second contact electrode 164 in the rigid portion A1. The adhesive layer 170 may be an anisotropic conductive film (ACF) including an insulating base member and a plurality of conductive balls 172 dispersed in the insulating base member.

[0140] When heat or pressure is applied to the adhesive layer 170, in the area where heat or pressure is applied, the conductive balls 172 can be electrically connected so that the adhesive layer 170 can have conductive characteristics, while in the area where heat or pressure is not applied, the adhesive layer 170 can have insulating characteristics.

[0141] The light-emitting element 180 can be disposed on the adhesive layer 170. The light-emitting element 180 can include a first electrode 182 and a second electrode 184.

[0142] Here, the first electrode 182 can be a p-electrode, and the second electrode 184 can be an n-electrode. The first electrode 182 can be an anode, and the second electrode 184 can be a cathode. However, the embodiments of the present disclosure are not limited thereto.

[0143] Alternatively, in other embodiments, the first electrode 182 can be an n-electrode, and the second electrode 184 can be a p-electrode. In this case, the first electrode 182 can be a cathode, and the second electrode 184 can be an anode.

[0144] The light-emitting element 180 can be provided in the form of a micro light-emitting diode chip (micro-LED chip or uLED chip) including an n-electrode, an n-type layer, an active layer, a p-type layer, and a p-electrode. The light-emitting element 180 can have a flip-chip structure in which the n-electrode and the p-electrode are disposed on the same side (e.g., the side facing the first substrate 101), and light is emitted through the side opposite to the side on which the n-electrode and the p-electrode are disposed (e.g., the side facing the second substrate 106).

[0145] However, the embodiments of the present disclosure are not limited thereto. The light-emitting element 180 can have a lateral structure in which the n-electrode and the p-electrode are disposed on the same side and light is emitted through the same side on which the n-electrode and the p-electrode are disposed, or can have a vertical structure in which the n-electrode and the p-electrode are respectively disposed on opposite sides.

[0146] The first electrode 182 of the light-emitting element 180 can overlap with the first contact electrode 162, and the second electrode 184 of the light-emitting element 180 can overlap with the second contact electrode 164. The first electrode 182 can be electrically connected to the first contact electrode 162 through the conductive balls 172 of the adhesive layer 170, and the second electrode 184 can be electrically connected to the second contact electrode 164 through the conductive balls 172 of the adhesive layer 170.

[0147] Meanwhile, the flexible printed circuit 192 can be attached to the stretchable wire 166 of the pad portion A3. The flexible printed circuit 192 can be connected to the source pad 136 through the stretchable wire 166 and the auxiliary pad 159.

[0148] The second adhesive layer 108 may be disposed on the light-emitting element 180 and the stretchable line 166, and the second substrate 106 may be disposed on the second adhesive layer 108.

[0149] The second adhesive layer 108 may attach the light-emitting element 180 and the stretchable line 166 to the second substrate 106. The second adhesive layer 108 may be formed of the same material as the first adhesive layer 102.

[0150] The second adhesive layer 108 may have a thickness substantially the same as that of the first adhesive layer 102.

[0151] In a stretchable display device according to an embodiment of the present disclosure, in order to achieve high resolution, the area of the flexible portion A2 may be minimized or reduced, and the length of the flexible portion A2 may also be reduced. The area of the flexible portion A2 may be smaller than the area of the rigid portion A1, and the length of the flexible portion A2 may be smaller than the length of the rigid portion A1. Therefore, since the length of the stretchable line 166 disposed in the flexible portion A2 can also be shortened, there is an advantage that the stretchable line 166 has a structure having relatively excellent stretchability and repeated stretch reliability.

[0152] Reference will be made to Figure 6 describe such a structure of the stretchable line according to an embodiment of the present disclosure.

[0153] Figure 6 is a schematic plan view of a flexible portion of a stretchable display device according to an embodiment of the present disclosure, and will be referred to together with Figures 1 to 5 be described.

[0154] As Figure 6 shown, in a stretchable display device according to an embodiment of the present disclosure, the flexible portion A2 may have a curved shape including straight portions and may have a substantially S-shaped shape.

[0155] Specifically, the flexible portion A2 may include a first straight portion S1 and a second straight portion S2 (also referred to as the first straight part S1 and the second straight part S2) and a first curved portion C1 and a second curved portion C2 (also referred to as the first curved part C1 and the second curved part C2). The first curved portion C1 and the second curved portion C2 may be interposed between the first straight portion S1 and the second straight portion S2 and may be provided to bulge in opposite directions.

[0156] The first linear portion S1 can be connected to a rigid portion A1, and the second linear portion S2 can be connected to another rigid portion A1 adjacent to the one rigid portion A1. Alternatively, the first linear portion S1 can be connected to the first pad portion A31, and the second linear portion S2 can be connected to the rigid portion A1 adjacent to the first pad portion A31, or the first linear portion S1 can be connected to the rigid portion A1 adjacent to the second pad portion A32, and the second linear portion S2 can be connected to the second pad portion A32.

[0157] The flexible portion A2 may include a base substrate 104 (i.e., the second base 104b) and a stretchable wire 166. The second base 104b and the stretchable wire 166 may have substantially the same shape as the flexible portion A2. That is, the second base 104b and the stretchable wire 166 may have a curved shape and may have a substantially S-shaped configuration.

[0158] Here, in a plan view, the second base 104b and the stretchable wire 166 may have substantially the same length and straight-line distance as the flexible portion A2, and the second base 104b may have a wider width and area than the stretchable wire 166. However, embodiments of the present disclosure are not limited thereto. Alternatively, in other embodiments, the stretchable wire 166 may have a wider width and area than the second base 104b.

[0159] The S-shaped stretchable wire 166 may be a part of an omega structure (e.g., an omega symbol Ω shape). Thus, the S-shaped flexible portion A2 may also be a part of the omega structure. Since the stretchable wire of the omega structure has a relatively large ratio of length to straight line, the stretchable wire of the omega structure may have relatively high stretchability.

[0160] The ratio of length to straight line is a value obtained by dividing the total length of the stretchable wire by the straight-line distance between both ends of the stretchable wire. As the ratio of length to straight line increases, the elongation rate may increase and the stretchability may be high.

[0161] In addition, compared with the stretchable wire of a waveform structure having the same ratio of length to straight line, the stretchable wire of the omega structure may have higher repeated stretch reliability. This ratio of length to straight line and repeated stretch reliability of such a stretchable wire will be described in detail with reference to Figures 7A to 7C and Figure 8 This ratio of length to straight line and repeated stretch reliability of such a stretchable wire will be described in detail with reference to

[0162] Figure 7A is a schematic plan view showing the structure of a stretchable wire according to an embodiment of the present disclosure, Figure 7B is a schematic plan view showing the structure of a stretchable wire according to a first comparative example, and Figure 7C is a schematic plan view showing the structure of a stretchable wire according to a second comparative example.

[0163] In Figure 7A , the stretchable wire according to Embodiment EM of the present disclosure may have a substantially omega structure (e.g., including the shape of the omega symbol Ω). For example, the stretchable wire according to Embodiment EM of the present disclosure may have a structure in which two omega shapes are connected to each other (e.g., the ΩΩ shape).

[0164] Meanwhile, in Figure 7B , the stretchable wire according to the first comparative example COM1 may have a first waveform structure (e.g., a sine wave shape), and in Figure 7C , the stretchable wire according to the second comparative example COM2 may have a second waveform structure.

[0165] Here, the second waveform structure of the second comparative example COM2 may have a greater number of waveforms than the first waveform structure of the first comparative example COM1. For example, the first waveform structure may have three waveforms, while the second waveform structure may have four waveforms.

[0166] The ratio of the length of the stretchable wire according to Embodiment EM of the present disclosure to a straight line may be about 2.35, the ratio of the length of the stretchable wire according to the first comparative example COM1 to a straight line may be about 1.88, and the ratio of the length of the stretchable wire according to the second comparative example COM2 to a straight line may be about 2.5.

[0167] Reference will be made to Figure 8 to describe the repeated stretching reliability of a stretchable wire having a ratio of length to a straight line.

[0168] Figure 8 is a graph showing the repeated stretching reliability of the stretchable wires according to the embodiments and comparative examples of the present disclosure. Figure 8 shows the number of repeated stretches related to the ratio of length to a straight line when the resistance of the stretchable wire increases by 5% by repeatedly stretching the length of the stretchable wire by 20%. Here, the more the number of repeated stretches, the higher the repeated stretching reliability.

[0169] In Figure 8 , it can be seen that the stretchable wire with an omega structure according to Embodiment EM of the present disclosure may have a greater ratio of length to a straight line and higher repeated stretching reliability than the stretchable wire with the first waveform structure according to the first comparative example COM1.

[0170] Furthermore, it can be seen that compared with the stretchable wire with the second waveform structure according to the second comparative example COM2, the stretchable wire with an omega structure according to Embodiment EM of the present disclosure may have a slightly smaller ratio of length to a straight line but higher repeated stretching reliability.

[0171] Therefore, in the present disclosure, an omega structure having relatively high stretching characteristics and repeatable stretch reliability can be applied to a stretchable wire.

[0172] At this time, in order to achieve high resolution, a part of the omega structure can be applied to the stretchable wire, and the stretchable wire can have a substantially S-shaped configuration, thereby ensuring stretching characteristics and repeatable stretch reliability while reducing or minimizing the length of the stretchable wire.

[0173] A stretchable wire (which is a part of the omega structure) according to an embodiment of the present disclosure can have a length-to-straight-line ratio of about 2.12.

[0174] On the other hand, Figure 9 is a schematic plan view of a stretchable display device according to a comparative example. In Figure 9 it, a flexible part B2 provided with a stretchable wire can be provided between adjacent rigid parts B1, and the stretchable wire can include a part of a waveform structure.

[0175] A stretchable wire as a part of a waveform structure according to a comparative example can have a length-to-straight-line ratio of about 2.05, which is less than the length-to-straight-line ratio of a stretchable wire as a part of an omega structure according to an embodiment of the present disclosure.

[0176] Therefore, compared with a stretchable wire (which is a part of a waveform structure) according to a comparative example, a stretchable wire (which is a part of an omega structure) according to an embodiment of the present disclosure can have improved stretching characteristics and repeat stretch reliability, and can be applied to a high-resolution display device.

[0177] In addition, in a stretchable display device according to an embodiment of a stretchable wire having such a structure according to the present disclosure, in order to achieve high resolution, the rigid part A1 and the flexible part A2 can be rotated at a selected angle "θ" with respect to the first direction X and the second direction Y. This will be described with reference to Figure 10 and Figure 11A and Figure 11B for description.

[0178] Figure 10 is a schematic plan view of another setting structure of a stretchable display device according to an embodiment of the present disclosure. Figure 10 shows a configuration in which the rigid part A1 and the flexible part A2 are provided without rotation, and will be described with reference to Figure 1 for description.

[0179] In Figure 10In [the figure], the rigid part A1 and the flexible part A2 can be arranged so as not to rotate with respect to the first direction X and the second direction Y in the display panel 100. In this case, some of the rigid part A1 can be partially outside the display area DA and can be partially arranged in the non-display area NDA. For example, as shown in the area OB, some parts of the rigid part A1 and the flexible part A2 are arranged in the non-display area NDA. Viewed from a plan view, these parts in the area OB overlap with the non-display area NDA.

[0180] Therefore, the rigid part A11 outside the display area DA does not contribute to the resolution. For the same area, compared with the resolution of the Figure 1 setting structure, Figure 10 the resolution of the setting structure can be reduced.

[0181] Meanwhile, in the stretchable display device according to an embodiment of the present disclosure, when the rigid part A1 does not rotate and the flexible part A2 rotates, due to structural limitations, it is difficult to implement a stretchable display device, and this will be described with reference to Figure 11A and Figure 11B herein.

[0182] Figure 11A and Figure 11B are plan views of other setting structures of the stretchable display device according to an embodiment of the present disclosure, and show a configuration in which the rigid part A1 does not rotate and the flexible part A2 rotates. Here, Figure 11B the rotation angle of the flexible part A2 of Figure 11A can be greater than the rotation angle of the flexible part A2 of

[0183] In Figure 11A , in the case where the rigid part A1 does not rotate, the flexible part A2 rotates, and the rotation angle θ1 is relatively small, there may be an area OV where the stretchable lines overlap each other, making it impossible to arrange the stretchable lines.

[0184] In addition, in Figure 11B , in the case where the rigid part A1 does not rotate, the flexible part A2 rotates, and the rotation angle θ2 is relatively large (for example, greater than θ1; θ2>θ1), both ends of each stretchable line can overlap with the rigid part A1 (see the area OZ where the flexible part A2 and the rigid part A1 overlap each other when viewed from a plan view), and thus the actual length "b" of the stretchable line as the part in the spacing distance between adjacent rigid parts A1 can be shorter than the original length "b0" of the stretchable line.

[0185] Therefore, the ratio of the length to the straight line may decrease, and the stretching performance may decrease.

[0186] As described above, in the stretchable display device according to an embodiment of the present disclosure, the rigid portion A1 and the flexible portion A2 can rotate at a selected angle "θ" with respect to the first direction X and the second direction Y. At this time, as Figure 6 shown, the second base portion 140b having substantially the same shape as the flexible portion A2 and the stretchable line 166 can also rotate at the same rotation angle "θ" in the same direction as the flexible portion A2, and the rotation angle "θ" can be calculated as follows.

[0187] Figure 12 is a schematic plan view of the unrotated rigid portion and flexible portion according to an embodiment of the present disclosure, and Figure 13 is a schematic plan view of the rotated rigid portion and flexible portion according to an embodiment of the present disclosure. Figure 12 and Figure 13 show the lengths of the respective components, and will be described based on two adjacent rigid portions A1 in the first direction X and the flexible portion A2 therebetween.

[0188] In Figure 12 , one rigid portion A1 and one flexible portion A2 can form a unit, and when the rigid portion A1 and the flexible portion A2 do not rotate, the unit length "c" (in the x-axis direction) is the sum of the length "a" of the rigid portion A1 and the length "b" of the flexible portion A2.

[0189] That is, c = a + b. Here, the units of "a", "b", and "c" can be metric and μm.

[0190] The unit length "c" can depend on the resolution "R". The resolution "R" can be expressed in PPI (pixels per inch), which is the number of pixels per inch, and the unit length "c" is the value obtained by dividing 1 inch (25400 μm) by the resolution "R".

[0191] That is, c = 25400 / R.

[0192] For example, when the resolution "R" is 100 PPI, the unit length "c" can be 254 μm. At this time, when the rigid portion A1 and the flexible portion A2 do not rotate, the length "a" of the rigid portion A1 can be 127 μm, and the length "b" of the flexible portion can be 127 μm.

[0193] Meanwhile, in the embodiment of the present disclosure, since the stretchable line and the flexible portion A2 are portions having a substantially S-shaped omega structure, one end and the other end of each of the stretchable line and the flexible portion A2 can be spaced apart from each other in the second direction Y. Therefore, two rigid portions A1 adjacent to each other in the first direction X can be displaced from each other in the second direction Y by a spacing distance "d". For example, the spacing distance "d" can be 20 μm.

[0194] Next, in Figure 13 when the rigid portion A1 and the flexible portion A2 rotate clockwise by a rotation angle "θ" with respect to the first direction X and the second direction Y, the unit length "c" can correspond to the distance between the ends of two rigid portions A1 adjacent to each other in the first direction X.

[0195] That is, c = d / sinθ. Here, the unit of the rotation angle "θ" can be degrees.

[0196] Therefore, the rotation angle "θ" can be θ = arcsin(d / c).

[0197] At this time, as described above, since c = 25400 / R, the rotation angle "θ" can be θ = arcsin(d·R / 25400).

[0198] In addition, regarding Figure 13 the length "b1" of the rotating flexible portion A2, since tanθ = d / (a + b1), the length "b1" of the rotating flexible portion A2 can be b1 = (d / tanθ) - a.

[0199] Therefore, in the stretchable display device according to the embodiment of the present disclosure, the values obtained by calculating the length "b" of the non-rotating flexible portion A2, the length "b1" of the rotating flexible portion A2, and the rotation angle "θ" for each resolution "R" are shown in Table 1. Here, the length "a" of the rigid portion A1 can be 127 μm, and the spacing distance "d" can be 20 μm.

[0200] [Table 1]

[0201] R (PPI) c (μm) a (μm) b (μm) θ b1 (μm) 100 254 127 127 0 150 169.3 127 42.3 6.78 41.2 160 158.8 127 31.8 7.24 30.4 170 149.4 127 22.4 7.69 21.1 180 141.l 127 14.l 8.15 12.7

[0202] In Table 1, when the resolution "R" is 180 PPI, the length "b1" of the rotating flexible portion A2 can be less than 20 μm. In this case, the area for setting the stretchable line cannot be ensured. Therefore, if the resolution "R" is higher than 170 PPI, the stretchable display device cannot be realized.

[0203] Therefore, in the embodiment of the present disclosure, a method for realizing the resolution of the stretchable display device from 150 PPI to 170 PPI can be described. At this time, the rotation angle "θ" can be from 5 degrees to 10 degrees. In some embodiments, it can be beneficial that the rotation angle "θ" is from 6 degrees to 8 degrees.

[0204] Meanwhile, the length "b" of the non-rotating flexible portion A2 can have a value larger than the length "b1" of the rotating flexible portion A2. However, when the rigid portion A1 and the flexible portion A2 do not rotate, as Figure 10As shown, some of the rigid portions A11 may be outside the display area DA, so the resolution of the display device in which the rigid portion A1 and the flexible portion A2 rotate may be lower than that of the display device in which the rigid portion A1 and the flexible portion A2 do not rotate.

[0205] As described above, in the stretchable display device according to an embodiment of the present disclosure, by configuring the stretchable line and the flexible portion A2 as part of an omega structure and rotating the rigid portion A1, the flexible portion A2, and the stretchable line, a high resolution of 150 PPI to 170 PPI can be achieved.

[0206] In addition, in the present disclosure, a higher resolution can be achieved by reducing the area of the rigid portion. This will be described with reference to Figure 14 A stretchable display device according to another embodiment of the present disclosure will be described in detail.

[0207] Figure 14 FIG. is a schematic cross-sectional view of a stretchable display device according to another embodiment of the present disclosure. Figure 14 The cross-section corresponding to the line I-I' is shown, and will be described together with Figure 2 The stretchable display device according to another embodiment of the present disclosure has substantially the same configuration as the foregoing embodiment, except for the stretchable line. Components identical to those in the foregoing embodiment are denoted by the same reference numerals, and the description of the same components may be abbreviated or omitted. Figure 5

[0208] Figure 14 As shown, in the stretchable display device according to another embodiment of the present disclosure, the stretchable line 266 may be formed of the same material as the source electrode 152 and the drain electrode 154 and on the same layer.

[0209] Specifically, the source electrode 152, the drain electrode 154, the connection electrode 156, the second pad 258, and the stretchable line 266 may be disposed on the second interlayer insulating layer 150 of the rigid portion A1.

[0210] The stretchable line 266 may be in direct contact with the second pad 258 and may be formed integrally. The stretchable line 266 may extend and be disposed in the flexible portion A2 and the pad portion A3. At this time, the stretchable line 266 may be in direct contact with the auxiliary pad 259 in the pad portion A3 and may be formed integrally.

[0211] The stretchable line 266 may contact the top surface and the side surface of the second interlayer insulating layer 150 in the rigid portion A1 and the pad portion A3, and may also contact the side surface of the first interlayer insulating layer 140.

[0212] In addition, the stretchable wire 266 may be in contact with the first buffer layer 110 in the flexible portion A2. Alternatively, when the first buffer layer 110 is completely removed in the flexible portion A2, the stretchable wire 266 may be in contact with the base substrate 104.

[0213] The planarization layer 160 may be disposed on the source electrode 152, drain electrode 154, connection electrode 156, second pad 258, and stretchable wire 266 of the rigid portion A1. In addition, the planarization layer 160 may be disposed on the stretchable wire 266 of the pad portion A3 and may not be disposed in the flexible portion A2.

[0214] The planarization layer 160 may cover the stretchable wire 266 of the rigid portion A1 and the pad portion A3 and may expose the stretchable wire 266 of the flexible portion A2.

[0215] In addition, the planarization layer 160 may not cover and may expose the auxiliary pad 259 of the pad portion A3.

[0216] The first contact electrode 162 and the second contact electrode 164 may be disposed on the planarization layer 160 of the rigid portion A1.

[0217] In a stretchable display device according to another embodiment of the present disclosure, by forming the stretchable wire 266 of the same material on the same layer as the source electrode 152 and the drain electrode 154, the contact hole for connecting the second pad 258 and the stretchable wire 266 may be omitted, and the horizontal distance between the stretchable wire 266 and / or the second pad 258 and the first contact electrode 162 may be minimized or reduced. Therefore, compared with Figure 5 the embodiment of, the area of the rigid portion A1 may be reduced.

[0218] On the other hand, in Figure 5 the embodiment of, since the stretchable wire 166 is formed of the same material as the first contact electrode 162 and the second contact electrode 164 and on the same layer, a contact hole for connecting the stretchable wire 166 and the second pad 158 may be required. In addition, in order to prevent or reduce the electrical short circuit between the stretchable wire 166 and the first contact electrode 162 and / or the light-emitting element 180 by overlapping the adhesive layer 170 disposed on the first contact electrode 162 and the second contact electrode 164 with the stretchable wire 166, the stretchable wire 166 and / or the second pad 158 may be spaced apart from the first contact electrode 162 at a selected distance therebetween.

[0219] Figure 14 The horizontal distance between the stretchable wire 266 and / or the second pad 258 of and the first contact electrode 162 may be less than Figure 5The horizontal distance between the stretchable line 166 and / or the second pad 158 and the first contact electrode 162. Accordingly, in a stretchable display device according to another embodiment of the present disclosure, compared with the previous embodiment, the length of the rigid portion A1 can be reduced, and thus the area of the rigid portion A1 can be reduced, thereby further improving the resolution.

[0220] For example, in a stretchable display device according to another embodiment of the present disclosure, the length of the rigid portion A1 can be 99 μm, and a resolution higher than 170 PPI can be achieved.

[0221] In a stretchable display device according to another embodiment of the present disclosure, values obtained by calculating the length "b" of the unrotated flexible portion A2, the length "b1" of the rotated flexible portion A2, and the rotation angle "θ" for each resolution "R" are shown in Table 2. Here, the length "a" of the rigid portion A1 can be 99 μm, and the spacing distance "d" can be 20 μm.

[0222] [Table 2]

[0223] [2R (PPI) c (μm) a (μm) b (μm) θ bl (μm) 150 169.3 99 70.3 6.78 69.2 160 158.8 99 59.8 7.24 58.4 170 149.4 99 50.4 7.69 49.1 180 141.1 99 42.1 8.15 40.7 190 133.7 99 34.7 8.60 33.2 200 127.0 99 28.0 9.06 26.4 210 121.0 99 22.0 9.52 20.3 220 115.5 99 16.5 9.98 14.7

[0224] In Table 2, when the resolution "R" is 220 PPI, the length "b1" of the rotated flexible portion A2 can be less than 20 μm. In this case, an area for setting the stretchable line cannot be ensured. Therefore, if the resolution "R" is higher than 210 PPI, a stretchable display device cannot be achieved.

[0225] Accordingly, in another embodiment of the present disclosure, the resolution of the stretchable display device can be achieved from 150 PPI to 210 PPI. At this time, the rotation angle "θ" can be from 5 degrees to 10 degrees, preferably from 6 degrees to 10 degrees.

[0226] Meanwhile, the base substrate 104 of the flexible portion A2, that is, the second base portion 104b, can be formed by selectively removing the base layer through a dry etching process after forming a hard mask on the stretchable line 166 or 266, and can be over-etched in some areas so as to be completely etched over the entire display area DA.

[0227] At this time, due to the anisotropy of the dry etching, the side surface of the second base portion 104b can be inclined. As the thickness of the base substrate 104 decreases, the side surface of the second base portion 104b has an increasing inclination angle. When the inclination angle increases, a designed unilateral edge, which is the distance between an edge of the stretchable line 166 or 266 and a corresponding edge of the hard mask, can be reduced, and a final unilateral margin, which is the distance between an edge of the stretchable line 166 or 266 and an edge of the second base portion 104b, can also be reduced.

[0228] Therefore, in an embodiment of the present disclosure, by reducing the thickness of the base substrate 104, the stretching characteristics of the stretchable wire 166 or 266 having the same ratio of length to straight line can be further improved.

[0229] The thickness of the base substrate 104 according to an embodiment of the present disclosure may be less than 6 μm, and advantageously may be 2 μm to 5 μm, and the final unilateral margin may be less than 2 μm.

[0230] For example, when the thickness of the base substrate 104 is about 4 μm and the width of the stretchable wire 166 or 266 is about 6 μm, the width of the second base portion 104b may be about 8 μm, and the final unilateral margin may be about 1 μm.

[0231] In the foregoing embodiment, it has been described that the rigid portion A1 and the flexible portion A2 rotate clockwise with respect to the first direction X and the second direction Y, but the embodiments of the present disclosure are not limited thereto. In other embodiments, the rigid portion A1 and the flexible portion A2 may rotate counterclockwise with respect to the first direction X and the second direction Y, and in this case, the flexible portion A2 and the stretchable wire may have a substantially left-right inverted S-shaped configuration.

[0232] In the stretchable display device of the present disclosure, by providing a stretchable wire having a structure with relatively high stretching characteristics and repeated stretching reliability, the area of the flexible portion can be reduced, high resolution can be achieved, and by increasing the lifespan of the stretchable wire, the production power consumption can be reduced to achieve low power consumption.

[0233] In addition, compared with a device having the same size, the resolution can be increased by rotating the rigid portion, the flexible portion, and the stretchable wire.

[0234] Furthermore, by forming a stretchable wire of the same material on the same layer as the source electrode and the drain electrode, the area of the rigid portion can be further reduced, thereby achieving higher resolution.

[0235] It will be apparent to those skilled in the art that various modifications and variations can be made to the display device of the present invention without departing from the technical idea or scope of the present invention. Therefore, the present disclosure is intended to cover modifications and variations that fall within the scope of the present disclosure.

[0236] The above various embodiments can be combined to provide further embodiments. If necessary, aspects of the embodiments can be modified to adopt concepts of various patents, applications, and publications to provide additional embodiments.

[0237] Based on the above detailed description, these and other changes can be made to the embodiments. Generally, in the appended claims, the terms used should not be construed as limiting the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments and the full scope of equivalents to which these claims are entitled. Therefore, the claims are not limited by the present disclosure.

[0238] Cross - reference to related applications

[0239] This application claims priority to Korean Patent Application No. 10 - 2023 - 0194834, filed in Korea on December 28, 2023, the entire contents of which are hereby incorporated by reference in their entirety.

Claims

1. A stretchable display device, the stretchable display device comprising: A first substrate, the first substrate including a display area and a non-display area; A plurality of rigid portions, the plurality of rigid portions being disposed in the display area on the first substrate and spaced apart from each other in both a first direction and a second direction intersecting the first direction; A flexible portion, the flexible portion being disposed between the rigid portions adjacent in the first direction or the second direction; And A second substrate, the second substrate being disposed on the first substrate, Wherein, the rigid portion and the flexible portion are rotated by a rotation angle with respect to the first direction and the second direction.

2. The stretchable display device according to claim 1, Among them, In the same direction, the length of the flexible portion is less than the length of the rigid portion, Wherein, the rotation angle is θ, and θ = arcsin(d·R / 25400), and Wherein, "d” is the spacing distance between two rigid portions adjacent to each other in the first direction and offset from each other in the second direction when the rigid portion and the flexible portion are not rotated, and "R” is the resolution as the number of pixels per inch.

3. The stretchable display device according to claim 1, wherein, The rotation angle is equal to or greater than 5 degrees and less than or equal to 10 degrees.

4. The stretchable display device according to claim 1, wherein, The flexible portion includes a first straight portion, a second straight portion, a first curved portion, and a second curved portion, and Wherein, the first curved portion and the second curved portion are disposed between the first straight portion and the second straight portion and are convexly disposed in opposite directions.

5. The stretchable display device according to claim 4, wherein, The flexible portion includes an S-shaped configuration.

6. The stretchable display device according to claim 1, the stretchable display device further comprising: Pixels, the pixels being disposed in each of the plurality of rigid portions and the pixels including a plurality of sub-pixels; And Stretchable lines, the stretchable lines being disposed in the flexible portion and connecting adjacent pixels.

7. The stretchable display device according to claim 6, wherein, The plurality of sub-pixels and the stretchable lines are rotated in the same direction as the rigid portion and the flexible portion.

8. The stretchable display device according to claim 6, wherein, The plurality of sub-pixels are not rotated with respect to the first direction and the second direction, and the long sides of the plurality of sub-pixels are parallel to the second direction, and Wherein, the stretchable lines are rotated in the same direction as the rigid portion and the flexible portion.

9. The stretchable display device according to claim 6, wherein, Each of the plurality of sub-pixels includes a thin film transistor and a light emitting element electrically connected to the thin film transistor, and Wherein, the stretchable lines are formed of the same material as the source electrode and the drain electrode of the thin film transistor and are formed on the same layer as the source electrode and the drain electrode of the thin film transistor.

10. The stretchable display device according to claim 1, the stretchable display device further comprising a pad portion disposed in the non-display area on the first substrate, Among them, The flexible portion is further disposed between the pad portion and the rigid portion adjacent to the pad portion.

11. The stretchable display device according to claim 10, wherein, The pad portion is disposed in a pattern with the rigid portion disposed in the first direction, and Wherein, a side of the pad portion facing the display area has a prismatic shape or a serrated shape.

12. A stretchable display device, the stretchable display device comprising A display panel that extends in a first direction and a second direction intersecting the first direction, the display panel comprising: A first substrate; A plurality of rigid portions disposed on the first substrate and spaced apart from each other; A pad portion disposed on the first substrate in a non-display area; A plurality of flexible portions between adjacent rigid portions, wherein the plurality of flexible portions are also disposed between the pad portion and the rigid portions; A plurality of sub-pixels, which, when viewed in a plan view, are disposed to overlap the plurality of rigid portions; A plurality of stretchable lines including a first group and a second group, wherein the first group of the plurality of stretchable lines is coupled between adjacent rigid portions, and the second group of the plurality of stretchable lines is coupled between the pad portion and a rigid portion among the plurality of rigid portions; Wherein each stretchable line of the plurality of stretchable lines includes at least one curved portion and at least one straight portion, and the at least one straight portion is continuously and adjacently coupled to the at least one curved portion; Wherein the at least one straight portion of the stretchable line extends in a third direction, and Wherein the third direction is different from both the first direction and the second direction.

13. The stretchable display device according to claim 12, wherein, When viewed in a plan view, the plurality of rigid portions are spaced apart from each other, Wherein, when viewed in a plan view, a first rigid portion among the plurality of rigid portions includes a first side and a second side, and Wherein the first side of the first rigid portion is rotated by a first tilt angle with respect to the first direction of the display panel.

14. The stretchable display device according to claim 13, wherein, The third direction of the at least one straight portion of the stretchable line is rotated by a second tilt angle with respect to the first direction of the display panel.

15. The stretchable display device according to claim 14, wherein, The first tilt angle and the second tilt angle are the same as each other.

16. The stretchable display device according to claim 14, wherein, The first tilt angle and the second tilt angle are different from each other.

17. The stretchable display device according to claim 14, wherein, Each sub-pixel of the plurality of sub-pixels has a first side and a second side, Wherein the first side of the sub-pixel is rotated by a third tilt angle with respect to the first direction of the display panel.

18. The stretchable display device according to claim 17, wherein, The third tilt angle is the same as the first tilt angle or the second tilt angle.

19. The stretchable display device according to claim 14, wherein, Each sub-pixel of the plurality of sub-pixels has a first side and a second side, Wherein the first side of the sub-pixel is aligned with the first direction of the display panel.

20. The stretchable display device according to claim 14, wherein, The at least one straight portion and the at least one curved portion of the stretchable line combine to form an "S-shaped" shape.

21. The stretchable display device according to claim 14, wherein, The at least one straight portion and the at least one curved portion of the stretchable line combine to form an "Ω-shaped" shape.

22. The stretchable display device according to claim 14, wherein, The first tilt angle and the second tilt angle are equal to or greater than 5 degrees and less than or equal to 10 degrees.

23. The stretchable display device according to claim 17, wherein, The third tilt angle is greater than or equal to 5 degrees and less than or equal to 10 degrees.

24. The stretchable display device according to claim 12, wherein, The pad portion includes a first group and a second group, Wherein, when viewed in a plan view, the first group of the pad portion has a rectangular shape, and Wherein, when viewed in a plan view, the second group of the pad portion has a serrated shape.

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