Indication device

Abstract

This invention provides a stretchable display device that enhances durability by improving surface hardness and scratch resistance, and improves ease of use by ensuring tacki-less properties that reduce surface stickiness and slip properties that regulate frictional force. [Solution] An embodiment of the present invention includes a display panel comprising a first stretched substrate, a plurality of sub-pixels spaced apart from each other, a plurality of stretchable connecting wires connecting the sub-pixels, a second stretched substrate, and at least one cover substrate disposed outside the display panel, characterized in that the tensile modulus of the cover substrate is higher than that of the first stretched substrate and the second stretched substrate.

Description

Technical Field

[0001] The present invention relates to a display device, and more particularly to a stretchable display device that can be stretched.

Background Art

[0002] Display devices used in computer monitors, TVs, mobile phones, etc. include organic light-emitting display devices (OLEDs) that emit light by themselves, and liquid crystal display devices (LCDs) that require a separate light source.

[0003] The application range of display devices is diverse not only for computer monitors and TVs but also for personal portable devices, and research is underway on display devices that have a reduced volume and weight while having a large display area.

[0004] In recent years, display devices formed by forming a display portion, wiring, etc. on a flexible substrate such as plastic, which is a flexible (flexible) material, and capable of stretching and contracting in a specific direction and being manufactured in various shapes have attracted attention as next-generation display devices.

[0005] Stretchable display devices that can be stretched and contracted are used for wearable, new concept furniture, and various space utilization and designs because they easily warp and have the property of stretching.

Summary of the Invention

Problems to be Solved by the Invention

[0006] The problem to be solved in the present invention is to provide a stretchable display device that improves surface hardness and scratch resistance to enhance durability, and secures Tacki-less characteristics that reduce surface stickiness and Slip characteristics that adjust frictional force to enhance usability.

[0007] Furthermore, another problem that the present invention aims to solve is to provide a stretchable display device that is durable against various mechanical deformations such as stretching, twisting, and bending, ensuring practicality in a wearable environment, and embodying structural flexibility that allows it to naturally deform to match the shape and style of clothing.

[0008] Furthermore, another problem that the present invention aims to solve is to develop surface properties that take into account skin adhesion and wearing comfort, thereby enhancing suitability as a wearable device and improving the overall performance and competitiveness of the product.

[0009] The problems addressed by the present invention are not limited to those mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0010] To solve the aforementioned problems, a display device according to one embodiment of the present invention includes a display panel comprising a first stretched substrate, a plurality of subpixels spaced apart from each other on the first stretched substrate, a plurality of stretchable connecting wires connecting the subpixels, a second stretched substrate, and at least one cover substrate disposed outside the display panel, characterized in that the tensile modulus of the cover substrate is higher than that of the first stretched substrate and the second stretched substrate.

[0011] Another embodiment of the present invention includes a first cover substrate, a stretchable display panel, a stretchable touch panel on the stretchable display panel, and a second cover substrate on the stretchable touch panel, characterized in that the tensile modulus of the first cover substrate and the second cover substrate is higher than the tensile modulus of the stretched substrate included in the stretchable display panel.

[0012] Another embodiment of the present invention relates to a display device comprising a first cover substrate, a display panel disposed on the first cover substrate, the display panel including a first stretched substrate, a plurality of subpixels disposed on the first stretched substrate, a plurality of stretchable connecting lines connecting the plurality of subpixels, and a second stretched substrate disposed on the plurality of subpixels and the plurality of connecting lines, a second cover substrate disposed on the display panel, and a third cover substrate disposed between the display panel and the second cover substrate, wherein the planar area of ​​the first cover substrate and the planar area of ​​the second cover substrate are each greater than the planar area of ​​the third cover substrate.

[0013] Specific details of other embodiments are included in the detailed description and drawings.

[0014] The display device of the present invention ensures structural stability through a cover substrate having a high tensile modulus, protecting internal components from external shocks and pressures. This enhances the device's durability and allows it to maintain stable performance even during prolonged use. In particular, it provides a design suitable for deformable devices such as wearable devices, thereby increasing reliability.

[0015] Furthermore, the cover coating layer of the present invention provides tacki-less properties that reduce surface stickiness, and the application of a nano cross linker significantly improves slip properties. Through this, the ease of handling and adaptability to the external environment of the device can be enhanced, and surface damage that may occur during transport can be prevented.

[0016] The effects of the present invention are not limited to those exemplified above, and a wide variety of other effects are included within the present invention. [Brief explanation of the drawing]

[0017] [Figure 1] This is a schematic plan view showing a display device according to an embodiment of the present invention. [Figure 2] This is a cross-sectional view taken along line II-II' shown in Figure 1. [Figure 3]It is a plan view showing a display panel included in the display device of FIG. 1. [Figure 4] It is an enlarged plan view showing an example of part A of FIG. 3. [Figure 5] It is a cross-sectional view showing an example cut along the V-V' line shown in FIG. 4. [Figure 6] It is a plan view explaining the non-stretched state and the stretched state of the display panel included in the display device of FIG. 1. [Figure 7a] It is a graph showing the relationship between the tensile strain and the tensile strength of the first cover substrate during tension and contraction. [Figure 7b] It is a graph showing the relationship between the tensile strain and the tensile strength of the second cover substrate during tension and contraction. [Figure 8] It is a view showing the neutral plane of the display device. [Figure 9] It is a cross-sectional view of a display device according to another embodiment of the present invention. [Figure 10] It is a plan view schematically showing a display device according to an embodiment of the present invention. [Figure 11] It is a cross-sectional view cut along the X-X' shown in FIG. 10.

Mode for Carrying Out the Invention

[0018] The advantages, features, and the methods for achieving them of the present invention will become clear by referring to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and can be embodied in various different shapes. Simply, these embodiments are provided so that the disclosure of the present invention becomes complete and that those with ordinary knowledge in the technical field to which the present invention pertains can fully know the scope of the invention. The present invention is only defined by the scope of the claims.

[0019] The shapes, areas, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative, and thus the present invention is not limited to the illustrated matters. Throughout the specification, the same reference numerals refer to the same components. Also, in explaining the present invention, when it is determined that a specific explanation of related known technologies may obscure the gist of the present invention, the detailed explanation thereof is omitted. When terms such as "including", "having", and "being made" are used in the present invention, unless "only" is used, other parts can be added. When a component is expressed in the singular, it includes the case of including a plurality unless otherwise explicitly stated.

[0020] When interpreting a component, it is interpreted as including an error range even without a separate explicit description.

[0021] And when described as "connected" or "coupled", unless "immediately" or "directly" is used, it can include being "connected" or "coupled" through one or more other components located between two components.

[0022] In this specification, the term "footprint" refers to the lateral extent or outer shape of a layer in a plane parallel to the principal plane of a display device, and includes the planar region occupied by the layer.

[0023] Also, first, second, etc. are used to describe various components, but these components are not limited by these terms. These terms are merely used to distinguish one component from another. Thus, the first component referred to below may be the second component within the technical idea of the present invention.

[0024] Throughout the specification, the same reference numerals refer to the same components.

[0025] The area and thickness of each component shown in the drawings are provided for illustrative purposes only, and the present invention is not necessarily limited to the area and thickness of the components shown.

[0026] The features of each of the various embodiments of the present invention can be combined or linked together, either partially or entirely, enabling a wide range of technical interdependencies and drives. Each embodiment may be implemented independently of the others or together in relation to them.

[0027] In the following, various embodiments of the present invention will be described in detail with reference to the attached drawings.

[0028] The display device according to an embodiment of the present invention is a display device capable of displaying images even when bent or stretched, and may also be referred to as a stretchable display device, a expandable display device, or a stretchable display device. The display device not only has higher flexibility than conventional general display devices, but can also have stretchability. Therefore, not only can the user bend or stretch the display device, but the shape of the display device can also be freely changed by the user's operation. For example, if the user holds the end of the display device and pulls it, the display device may stretch in the direction the user is pulling. Or, if the user places the display device on an uneven surface, the display device may be positioned to bend along the shape of the outer surface of the wall. Furthermore, when the force applied by the user is removed, the display device can be restored to its original shape.

[0029] Figure 1 is a schematic plan view showing a display device according to an embodiment of the present invention.

[0030] Figure 2 is a cross-sectional view taken along line II-II' shown in Figure 1.

[0031] Referring to Figures 1 and 2, the display device 1000 includes a printed circuit board (PCB), a display panel 100, a touch panel 200, a first cover board CS1, a second cover board CS2, and a third cover board CS3.

[0032] The display panel 100 stretches even under deformation conditions such as stretching and bending, outputting images and videos and operating stably. The display panel 100 maintains consistent image quality by adjusting the spacing between pixels through deformation during stretching. A detailed explanation of this will be provided later with reference to Figures 3 to 5.

[0033] The touch panel 200 is attached to the top of the display panel 100 using an ADD-on method and plays the role of sensing user input and converting it into electrical signals. The touch panel 200 employs a stretchable touch sensor, enabling accurate input even in deformable environments such as stretching and bending, and utilizes electrostatic touch technology and transparent conductive materials (e.g., graphene or ITO) to provide high sensitivity and light transmittance. The ADD-on method of the touch panel 200 ensures structural unity while maintaining the independence of the touch panel and the display panel, and supports multi-touch and gesture recognition. Through this, it provides a precise and reliable user interface in various environments such as wearable devices while maintaining video output quality.

[0034] The first cover substrate CS1 protects the display panel 100 and the touch panel 200 from below and provides structural stability. The first cover substrate CS1 is positioned at the bottom end of the display device 1000 and is bonded to the display panel 100 through optical adhesive OCA. In Figures 1 and 2, the first cover substrate CS1 may be formed to be wider than the display panel 100 and the touch panel 200, but it may also be formed to be the same size as the display panel 100 and the touch panel 200.

[0035] The second cover substrate CS2 protects the top of the display panel 100 and the touch panel 200, protecting the device from the external environment and providing structural stability. The second cover substrate CS2 is positioned at the top edge of the display device 1000 and is bonded to the touch panel 200 through optical adhesive OCA. In Figures 1 and 2, the second cover substrate CS2 may be formed to be wider than the display panel 100 and the touch panel 200, but it may also be formed to the same size as the display panel 100 and the touch panel 200.

[0036] The third cover substrate CS3 is positioned between the display panel 100 and the touch panel 200, protecting the intermediate layer and providing structural stability. The third cover substrate CS3 is placed between the display panel 100 and the touch panel 200 of the display device 1000 and is bonded to each component through optical adhesive OCA. In Figures 1 and 2, the third cover substrate CS3 can be formed to match the size of the display panel 100 and the touch panel 200.

[0037] Multiple cover substrates CS1, CS2, and CS3 can be made of polymer film or elastic material to enhance durability and absorb mechanical shock. Furthermore, the multiple cover substrates CS1, CS2, and CS3 combine lightness and flexibility to maintain stretchability, and transparent materials are used to avoid affecting optical performance. Through this, the durability of the display device 1000 is increased, and the internal components are effectively protected from external shocks and environmental factors.

[0038] Figure 3 is a plan view showing the display panel included in the display device shown in Figure 1.

[0039] Figure 4 is an enlarged plan view showing an example of part A in Figure 3.

[0040] Figure 5 is a cross-sectional view showing an example of a section cut along the line V-V' shown in Figure 4.

[0041] Figure 6 is a plan view illustrating the unstretched and stretched states of the display panel included in the display device shown in Figure 1.

[0042] First, referring to Figures 3 and 5, the display panel 100 of the present invention may include a lower substrate 111, a pattern layer 120, a plurality of pixels PX, a gate driver GD, a data driver DD, a power supply PS, and a printed circuit board PCB. In one embodiment, the display panel 100 may further include an upper substrate 112.

[0043] The lower substrate 111 supports a pattern layer 120 on which pixels PX, gate drivers GD, and power supplies PS are formed, and the upper substrate 112 is placed on the lower substrate 111 and can cover various components of the display panel 100. In one embodiment, the lower substrate 111 and the upper substrate 112 may each be stretchable substrates made of an insulating material that can be bent and stretched. Thus, the lower substrate 111 may be referred to as the first stretchable substrate.

[0044] The tensile modulus of the lower substrate 111 and the upper substrate 112 may be 1 MPa or less. The ductile breaking rate of the lower substrate 111 and the upper substrate 112 may be 100% or more. Here, the ductile breaking rate refers to the elongation rate at the point when the object being stretched breaks or cracks.

[0045] The lower substrate 111 may include an active area AA (or display area) and a non-active area NA (or non-display area) excluding the active area AA. For example, the non-active area NA may surround the active area AA.

[0046] Multiple pixels PX, each containing display elements and circuit elements, may be arranged on the active region AA. Additionally, gate drivers GD and power supplies PS for driving the multiple pixels PX arranged in the active region AA may be arranged on the inactive region NA.

[0047] A pattern layer 120 may be placed on the lower substrate 111.

[0048] In one embodiment, the pattern layer 120 may include a plurality of first plate patterns 121 and a plurality of first line patterns 122 arranged in the active region AA, and a plurality of second plate patterns 123 and a plurality of second line patterns 124 arranged in the inactive region NA.

[0049] Multiple first plate patterns 121 are arranged in the active region AA of the lower substrate 111, and multiple pixels PX may be formed on the multiple first plate patterns 121. Multiple second plate patterns 123 are arranged in the inactive region NA of the lower substrate 111, and gate drivers GD and power supplies PS may be formed on the multiple second plate patterns 123.

[0050] Furthermore, although Figure 3 shows that the multiple first plate patterns 121 and multiple second plate patterns 123 have a rectangular shape, the design is not limited to this and can be transformed into a variety of shapes.

[0051] Referring to Figure 3, the pattern layer 120 may further include a plurality of first line patterns 122 located in the active region AA and a plurality of second line patterns 124 located in the inactive region NA.

[0052] Multiple first wiring patterns 122 are arranged in the active region AA and are patterns that connect adjacent first plate patterns 121 to each other, and may be referred to as first connecting patterns.

[0053] Multiple second wiring patterns 124 are arranged in an inactive region NA and may be patterns that connect adjacent first board patterns 121 and second board patterns 123, or connect multiple adjacent second board patterns 123.

[0054] Referring to Figure 3, the multiple first wiring patterns 122 and second wiring patterns 124 may have a bent shape (e.g., sinusoidal), but are not limited to this, and the multiple first wiring patterns 122 and second wiring patterns 124 may have a variety of shapes, such as extending in a zigzag shape or extending with multiple rhombus-shaped substrates connected at their vertices.

[0055] In one embodiment, the plurality of first plate patterns 121, plurality of first wiring patterns 122, plurality of second plate patterns 123, and plurality of second wiring patterns 124 may be rigid patterns. That is, the plurality of first plate patterns 121, plurality of first wiring patterns 122, plurality of second plate patterns 123, and plurality of second wiring patterns 124 may be more rigid than the lower substrate 111 and the upper substrate 112 described later. Therefore, the tensile modulus and hardness of the plurality of first plate patterns 121, plurality of first wiring patterns 122, plurality of second plate patterns 123, and plurality of second wiring patterns 124 may be higher than the tensile modulus of the lower substrate 111 and the upper substrate 112. The tensile modulus of the multiple first plate patterns 121, multiple first wiring patterns 122, multiple second plate patterns 123, and multiple second wiring patterns 124 may be 1000 times or more higher than the tensile modulus of the lower substrate 111 and upper substrate 112, but is not limited thereto.

[0056] Multiple rigid substrates, consisting of multiple first plate patterns 121, multiple first wiring patterns 122, multiple second plate patterns 123, and multiple second wiring patterns 124, may be made of a plastic material having lower flexibility than the lower substrate 111 and the upper substrate 112 described later.

[0057] The gate driver GD can supply gate signals to multiple pixels PX located in the active region AA. The gate driver GD includes multiple stages formed on multiple second plate patterns 123, and each stage of the gate driver GD can be electrically connected to one another through multiple gate coupling lines. Therefore, a gate signal output from any one stage can be transmitted to the other stages. Each stage can sequentially supply gate signals to the multiple pixels PX connected to it.

[0058] The power supply PS is connected to the gate driver GD and can supply the gate drive voltage and gate clock voltage. Furthermore, the power supply PS can be connected to multiple pixels PX and can supply the pixel drive voltage to each of the multiple pixels PX.

[0059] A printed circuit board (PCB) can transmit signals and voltages from the control unit to the display elements for driving the display elements, including an IC chip, a circuit section, and / or memory, a processor, etc. To ensure stretchability, the printed circuit board (PCB) may include stretched and non-stretched regions. For example, IC chips, circuit sections, memory, processors, etc., may be mounted in the non-stretched regions, while wiring electrically connected to the IC chips, circuit sections, memory, and processors may be arranged in the stretched regions.

[0060] The data driver DD can supply data voltages to multiple pixels PX located in the active region AA. The data driver DD can be mounted in the non-stretched region of the printed circuit board (PCB).

[0061] Referring to Figures 3 and 4, multiple first plate patterns 121 can be arranged on the active region AA of the lower substrate 111. The multiple first plate patterns 121 can be arranged on the lower substrate 111 spaced apart from each other. For example, as shown in Figure 3, the multiple first plate patterns 121 can be arranged in a matrix on the lower substrate 111, but are not limited to this.

[0062] Referring to Figure 4, the first plate pattern 121 may have a pixel PX containing multiple subpixels SPX. Each subpixel SPX may include an LED 170, which is a display element, and a drive transistor 160 and a switching transistor 150 for driving the LED 170. However, the display element in the subpixel SPX is not limited to an LED and can be changed to an organic light-emitting diode.

[0063] Multiple subpixel SPXs may include, but are not limited to, red subpixels, green subpixels, and blue subpixels, and the hue of multiple subpixel SPXs can be varied in various ways as needed.

[0064] Multiple subpixel SPXs can be connected to multiple connecting wires 181, 182.

[0065] In the following section, the cross-sectional structure of the display panel 100 in the active region AA will be described in more detail with reference to Figure 5.

[0066] Referring to Figure 5, multiple inorganic insulating layers may be arranged on multiple first plate patterns 121. For example, the multiple inorganic insulating layers may include a buffer layer 141, a gate insulating layer 142, a first interlayer insulating layer 143, a second interlayer insulating layer 144, and a passivation layer 145. However, it is not limited to this, and various other inorganic insulating layers may be further arranged on multiple first plate patterns 121, or one or more of the inorganic insulating layers, namely the buffer layer 141, gate insulating layer 142, first interlayer insulating layer 143, second interlayer insulating layer 144, and passivation layer 145, may be omitted.

[0067] The buffer layer 141 may be placed on a plurality of first plate patterns 121. The buffer layer 141 contains an insulating material and may be formed on the plurality of first plate patterns 121 to protect various components of the display panel 100 from penetration of moisture (H2O) and oxygen (O2) from the outside of the lower substrate 111 and the plurality of first plate patterns 121. However, the buffer layer 141 may be omitted depending on the structure and characteristics of the display panel 100.

[0068] In one embodiment, the buffer layer 141 may be formed only in the region where the lower substrate 111 overlaps with the plurality of first plate patterns 121 and the plurality of second plate patterns 123. As described above, since the buffer layer 141 may be made of inorganic material, it can be easily damaged, such as cracking, during the stretching process of the display panel 100. Therefore, the buffer layer 141 may not be formed in the region between the plurality of first plate patterns 121 and the plurality of second plate patterns 123, but may be patterned to match the shape of the plurality of first plate patterns 121 and the plurality of second plate patterns 123 and formed only on top of the plurality of first plate patterns 121 and the plurality of second plate patterns 123. Therefore, in the case of a display panel 100 according to one embodiment of the present invention and a display panel 100 including the same, the buffer layer 141 is formed only in the region where it overlaps with the multiple first plate patterns 121 and the multiple second plate patterns 123, which are rigid patterns. This prevents damage to various components of the display panel 100 even when the display panel 100 is deformed, such as by warping or stretching.

[0069] Referring to Figure 5, a switching transistor 150 including a gate electrode 151, an active layer 152, a source electrode 153, and a drain electrode 154, and a driving transistor 160 including a gate electrode 161, an active layer 162, a source electrode, and a drain electrode 164 may be arranged on the buffer layer 141.

[0070] The active layer 152 of the switching transistor 150 and the active layer 162 of the driving transistor 160 may be placed on the buffer layer 141. For example, the active layer 152 of the switching transistor 150 and the active layer 162 of the driving transistor 160 may be formed from an oxide semiconductor, amorphous silicon (a-Si), polycrystalline silicon (poly-Si), or an organic semiconductor, etc.

[0071] A gate insulating layer 142 may be placed on the active layer 152 of the switching transistor 150 and on the active layer 162 of the driving transistor 160. The gate insulating layer 142 contains an insulating material and can electrically isolate the gate electrode 151 of the switching transistor 150 from the active layer 152 of the switching transistor 150, and electrically isolate the gate electrode 161 of the driving transistor 160 from the active layer 162 of the driving transistor 160.

[0072] The gate electrode 151 of the switching transistor 150 and the gate electrode 161 of the driving transistor 160 may be placed on the gate insulating layer 142. The gate electrode 151 of the switching transistor 150 and the gate electrode 161 of the driving transistor 160 may be placed on the gate insulating layer 142 so as to be spaced apart from each other. The gate electrode 151 of the switching transistor 150 may be superimposed on the active layer 152 of the switching transistor 150, and the gate electrode 161 of the driving transistor 160 may be superimposed on the active layer 162 of the driving transistor 160.

[0073] A first interlayer insulating layer 143 may be placed on the gate electrode 151 of the switching transistor 150 and the gate electrode 161 of the drive transistor 160. The first interlayer insulating layer 143 contains an insulating material and can insulate the gate electrode 161 of the drive transistor 160 from the intermediate metal layer IM.

[0074] An intermediate metal layer IM containing a metallic substance may be placed on the first interlayer insulating layer 143. The intermediate metal layer IM may be superimposed on the gate electrode 161 of the drive transistor 160. Thus, a storage capacitor can be formed in the superimposed region of the intermediate metal layer IM and the gate electrode 161 of the drive transistor 160. For example, the gate electrode 161 of the drive transistor 160, the first interlayer insulating layer 143, and the intermediate metal layer IM can form a storage capacitor. However, the placement region of the intermediate metal layer IM is not limited to this, and the intermediate metal layer IM can be superimposed on other electrodes to form storage capacitors in various ways.

[0075] A second interlayer insulating layer 144 may be placed on the intermediate metal layer IM. The second interlayer insulating layer 144 contains an insulating material and can insulate the gate electrode 151 of the switching transistor 150 from the source electrode 153 and drain electrode 154 of the switching transistor 150. Furthermore, the second interlayer insulating layer 144 can insulate the intermediate metal layer IM from the source electrode and drain electrode 164 of the drive transistor 160.

[0076] The source electrode 153 and drain electrode 154 of the switching transistor 150 may be placed on the second interlayer insulating layer 144. The source electrode 153 and drain electrode 154 of the driving transistor 160 may also be placed on the second interlayer insulating layer 144. The source electrode 153 and drain electrode 154 of the switching transistor 150 may be placed on the same layer but separated from each other.

[0077] On the other hand, although the source electrode of the drive transistor 160 is omitted in Figure 5, the source electrode of the drive transistor 160 can also be arranged on the same layer as the drain electrode 164, separated from it. In the switching transistor 150, the source electrode 153 and the drain electrode 154 can be electrically connected to the active layer 152 by contacting the active layer 152. In the drive transistor 160, the source electrode and the drain electrode 164 can be electrically connected to the active layer 162 by contacting the active layer 162. Furthermore, the drain electrode 154 of the switching transistor 150 can be electrically connected to the gate electrode 161 of the drive transistor 160 by contacting the gate electrode 161 of the drive transistor 160 through a contact hole.

[0078] A gate pad, a data pad DP, and a voltage pad VP may be placed on the second interlayer insulating layer 144.

[0079] Specifically, the gate pad can transmit a gate signal to multiple sub-pixel SPXs. The gate pad can be connected to a first connecting wiring 181 through a contact hole. The gate signal supplied from the first connecting wiring 181 can then be transmitted from the gate pad to the gate electrode 151 of the switching transistor 150 through wiring formed on the first board pattern 121.

[0080] The data pad DP can transmit data voltage to multiple sub-pixels SPX. The data pad DP can be connected to a second connecting wiring 182 through a contact hole. The data voltage supplied from the second connecting wiring 182 can then be transmitted from the data pad DP to the source electrode 153 of the switching transistor 150 through wiring formed on the first board pattern 121.

[0081] The voltage pad VP can then transmit a low potential voltage to multiple sub-pixels SPX. The voltage pad VP can be connected to the first connecting wiring 181 through a contact hole. The low potential voltage supplied from the first connecting wiring 181 can then be transmitted from the voltage pad VP to the n electrode 174 of the LED 170 through wiring formed on the first plate pattern 121.

[0082] The gate pad and data pad DP may, but are not limited to, be made of the same material as the source electrode 153 and drain electrodes 154, 164.

[0083] A passivation layer 145 may be formed on the switching transistor 150 and the drive transistor 160. That is, the passivation layer 145 may be arranged to cover the switching transistor 150 and the drive transistor 160 in order to protect them from the penetration of moisture and oxygen, etc. The passivation layer 145 may be made of inorganic material and may be a single layer or multiple layers, but is not limited thereto.

[0084] Furthermore, the gate insulating layer 142, the first interlayer insulating layer 143, the second interlayer insulating layer 144, and the passivation layer 145 can be formed only in areas that are patterned and superimposed on the multiple first plate patterns 121. The gate insulating layer 142, the first interlayer insulating layer 143, the second interlayer insulating layer 144, and the passivation layer 145 can also be made of inorganic material, similar to the buffer layer 141, and can be easily damaged, such as cracks occurring, during the stretching of the display panel 100 or the display panel 100. Therefore, the gate insulating layer 142, the first interlayer insulating layer 143, the second interlayer insulating layer 144, and the passivation layer 145 are not formed in areas between the multiple first plate patterns 121, but can be patterned to the shape of the multiple first plate patterns 121 and formed only on top of the multiple first plate patterns 121.

[0085] A planarization layer 146 can be formed on the passivation layer 145. The planarization layer 146 can planarize the top of the switching transistor 150 and the drive transistor 160. The planarization layer 146 may consist of one or more layers and may be made of an organic material.

[0086] The planarization layer 146 may be arranged on a plurality of first plate patterns 121 so as to cover the top and side surfaces of the buffer layer 141, gate insulation layer 142, first interlayer insulation layer 143, second interlayer insulation layer 144, and passivation layer 145. The planarization layer 146 may also be arranged together with the plurality of first plate patterns 121 so as to surround the buffer layer 141, gate insulation layer 142, first interlayer insulation layer 143, second interlayer insulation layer 144, and passivation layer 145. Specifically, the planarization layer 146 may be arranged so as to cover the top and side surfaces of the passivation layer 145, the side surfaces of the first interlayer insulation layer 143, the side surfaces of the second interlayer insulation layer 144, the side surfaces of the gate insulation layer 142, the side surfaces of the buffer layer 141, and a portion of the top surfaces of the plurality of first plate patterns 121. Therefore, the planarization layer 146 can compensate for the steps on the sides of the buffer layer 141, gate insulation layer 142, first interlayer insulation layer 143, second interlayer insulation layer 144, and passivation layer 145. Furthermore, the planarization layer 146 can increase the adhesive strength with the connecting wiring 181 and 182 that are placed on the sides of the planarization layer 146.

[0087] The inclination angle of the side surface of the flattening layer 146 may be smaller than the inclination angle formed by the side surfaces of the buffer layer 141, gate insulation layer 142, first interlayer insulation layer 143, second interlayer insulation layer 144, and passivation layer 145. For example, the side surface of the flattening layer 146 may have a gentler inclination than the side surfaces of the passivation layer 145, the first interlayer insulation layer 143, the second interlayer insulation layer 144, the gate insulation layer 142, and the buffer layer 141. Therefore, the connecting wirings 181 and 182, which are arranged in contact with the side surface of the flattening layer 146, are arranged with a gentle inclination, and the stress generated in the connecting wirings 181 and 182 when the display panel 100 is stretched can be reduced. Furthermore, the relatively gentle slope of the side surface of the planarized layer 146 suppresses the phenomenon of the connecting wiring 181 and 182 cracking or peeling off at the side surface of the planarized layer 146.

[0088] Referring to Figures 4 and 5, the connecting wires 181 and 182 can electrically connect pads on multiple first board patterns 121. The connecting wires 181 and 182 can be placed on multiple first wiring patterns 122. Furthermore, the connecting wires 181 and 182 can extend onto multiple first board patterns 121 in order to electrically connect to gate pads and data pads DP on multiple first board patterns 121. In the regions between multiple first board patterns 121 where the connecting wires 181 and 182 are not placed, the first wiring patterns 122 do not need to be placed.

[0089] The connecting wiring 181 and 182 may include a first connecting wiring 181 and a second connecting wiring 182. The first connecting wiring 181 and the second connecting wiring 182 may contain a metallic material and be arranged between a plurality of first plate patterns 121.

[0090] More specifically, the first connecting wiring 181 means wiring that extends in a first direction X from between multiple first plate patterns 121 among the connecting wirings 181 and 182, and the second connecting wiring 182 may be wiring that extends in a second direction Y from between multiple first plate patterns 121 among the connecting wirings 181 and 182.

[0091] On the other hand, in the case of a typical display panel for a display device, various wirings such as multiple gate lines and multiple data lines are arranged in a linear shape extending from between multiple subpixels, and multiple subpixels are connected to a single signal line. Therefore, in the case of a typical display panel for a display device, various wirings such as gate lines, data lines, high-voltage lines, and reference voltage lines extend from one side to the other side of the display panel for the organic light-emitting display device without being interrupted on the substrate.

[0092] In contrast, in the case of the display panel 100 included in the display device 1000 according to one embodiment of the present invention, various types of wiring, such as linear gate wiring, data wiring, high-potential voltage wiring, reference voltage wiring, and initialization voltage wiring, which are commonly used in the display panels of general display devices, can be arranged only on a plurality of first board patterns 121 and a plurality of second board patterns 123. That is, in the display panel 100 included in the display device 1000 according to one embodiment of the present invention, linear wiring can be arranged only on a plurality of first board patterns 121 and a plurality of second board patterns 123.

[0093] In the display panel 100 of the display device 1000 according to one embodiment of the present invention, pads on two adjacent first plate patterns 121 can be connected by connecting wires 181 and 182. Therefore, the connecting wires 181 and 182 can electrically connect gate pads or data pads DP on two adjacent first plate patterns 121. Accordingly, the display panel 100 included in the display device 1000 according to one embodiment of the present invention can include a plurality of connecting wires 181 and 182 to electrically connect various wirings such as gate wiring, data wiring, high potential voltage wiring, reference voltage wiring, etc., between a plurality of first plate patterns 121. For example, gate wiring may be arranged on a plurality of first plate patterns 121 arranged adjacent to each other in a first direction X, and gate pads may be arranged at both ends of the gate wiring. In this case, each of the plurality of gate pads on the plurality of first plate patterns 121 arranged adjacent to each other in a first direction X can be connected to each other by a first connecting wire 181 that functions as a gate wiring. Therefore, gate wiring arranged on multiple first board patterns 121 and first connecting wiring 181 arranged on the first wiring pattern 122 can function as a single gate wiring. The gate wiring described above may be named scan signal wiring. In addition, among all the various wirings that may be included in the display panel 100, wiring extending in the first direction X, such as light emission signal wiring, low potential voltage wiring, and high potential voltage wiring, can also be electrically connected by the first connecting wiring 181 as described above.

[0094] Referring to Figures 3 and 4, the first connecting wire 181 can connect two adjacent gate pads on a plurality of first plate patterns 121 arranged adjacently in a first direction X. The first connecting wire 181 can function as a gate wire, an illumination signal wire, a high-voltage wire, or a low-voltage wire, but is not limited to these functions. Multiple gate pads on the first plate patterns 121 arranged in a first direction X can be connected by the first connecting wire 181 functioning as a gate wire, and a single gate voltage can be transmitted.

[0095] Referring to Figures 3 and 4, the second connecting wiring 182 can connect two adjacent data pads DP on a plurality of first board patterns 121 that are arranged adjacently in the second direction Y. The second connecting wiring 182 can function as data wiring, high-voltage wiring, low-voltage wiring, or reference voltage wiring, but is not limited to these functions. Multiple internal wirings on the first board patterns 121 arranged in the second direction Y can be connected by multiple second connecting wirings 182 that function as data wiring, and a single data voltage can be transmitted.

[0096] On the other hand, referring to Figure 5, a bank 147 may be formed on the connecting pad CNT, connecting wiring 181, 182 and planarization layer 146. The bank 147 contains insulating material and can separate adjacent subpixel SPX. The bank 147 may be positioned to cover at least a portion of the connecting wiring 181, 182 and planarization layer 146. In Figure 4, the height of the bank 147 is shown to be lower than the height of the LED 170, but it is not limited to this, and the height of the bank 147 may be the same as the height of the LED 170.

[0097] An LED 170 may be placed on the connecting pad CNT and the first connecting wiring 181. The LED 170 may include an n-type layer 171, an active layer 172, a p-type layer 173, an n-electrode 174, and a p-electrode 175. The LED 170 of the display panel 100 according to one embodiment of the present invention may have a flip-chip structure in which the n-electrode 174 and the p-electrode 175 are formed on one side, but is not limited thereto.

[0098] The n-type layer 171 can be formed by implanting n-type impurities into gallium nitride (GaN) having excellent crystallinity. The n-type layer 171 may be placed on a separate base substrate made of a material capable of emitting light.

[0099] An active layer 172 may be placed on the n-type layer 171. The active layer 172 is a light-emitting layer that emits light in the LED 170 and may consist of a nitride semiconductor, such as indium gallium nitride (InGaN). A p-type layer 173 may be placed on the active layer 172. The p-type layer 173 may be formed by implanting p-type impurities into gallium nitride (GaN).

[0100] An LED 170 according to one embodiment of the present invention can be manufactured by sequentially stacking an n-type layer 171, an active layer 172, and a p-type layer 173, then etching a predetermined portion, and finally forming an n-electrode 174 and a p-electrode 175, as described above. In this case, the predetermined portion is a space for separating the n-electrode 174 and the p-electrode 175, and the predetermined portion can be etched so that a part of the n-type layer 171 is exposed. In other words, the surface of the LED 170 on which the n-electrode 174 and the p-electrode 175 are arranged may have different height levels that are not flattened surfaces.

[0101] Thus, an n-electrode 174 is placed in the etched region, and the n-electrode 174 may be made of a conductive material. A p-electrode 175 is placed in the unetched region, and the p-electrode 175 may also be made of a conductive material. For example, an n-electrode 174 may be placed on the n-type layer 171 exposed in the etching process, and a p-electrode 175 may be placed on the p-type layer 173. The p-electrode 175 may be made of the same material as the n-electrode 174.

[0102] The conductive adhesive layer AD is placed between the upper surface of the connecting pad CNT and the LED 170 and the connecting pad CNT and the LED 170, so that the LED 170 can be bonded onto the connecting pad CNT and the first connecting wiring 181. In this case, the n electrode 174 may be placed on the first connecting wiring 181, and the p electrode 175 may be placed on the connecting pad CNT.

[0103] The conductive adhesive layer AD may be an adhesive layer having conductivity due to conductive balls dispersed in an insulating base member. Therefore, when heat or pressure is applied to the conductive adhesive layer AD, the conductive balls are electrically connected in the heated or pressured area, resulting in conductive properties, while the unpressurized area may have insulating properties. For example, the n electrode 174 can be electrically connected to the first connecting wiring 181 through the conductive adhesive layer AD, and the p electrode 175 can be electrically connected to the connecting pad CNT through the conductive adhesive layer AD. After applying the conductive adhesive layer AD to the upper surface of the first connecting wiring 181 and the connecting pad CNT, an LED 170 can be transferred onto the conductive adhesive layer AD, and the connecting pad CNT and the p electrode 175, and the first connecting wiring 181 and the n electrode 174 can be electrically connected by applying heat to the LED 170 under pressure. However, portions of the conductive adhesive layer AD other than those positioned between the n electrode 174 and the first connecting wiring 181, and between the p electrode 175 and the connecting pad CNT, may have insulating properties. On the other hand, the conductive adhesive layer AD may be positioned in separate configurations on the connecting pad CNT and the first connecting wiring 181, respectively.

[0104] The connecting pad CNT is electrically connected to the drain electrode 164 of the drive transistor 160, and can receive a drive voltage from the drive transistor 160 to drive the LED 170. In Figure 4, it is shown that the connecting pad CNT and the drain electrode 164 of the drive transistor 160 are indirectly connected but not in direct contact. However, it is not limited to this, and the connecting pad CNT and the drain electrode 164 of the drive transistor 160 can also be in direct contact. A low-potential drive voltage for driving the LED 170 can be applied to the first connecting wiring 181. When the display panel 100 is turned on, the different voltage levels applied to the connecting pad CNT and the first connecting wiring 181 are transmitted to the n electrode 174 and p electrode 175, respectively, allowing the LED 170 to light up.

[0105] The upper substrate 112 supports various components located beneath it. The upper substrate 112 may be a substrate for covering and protecting various components of the display panel 100. For example, the upper substrate 112 may be a substrate that covers the pixels PX, gate drivers GD, and power supply PS, which are components of the display panel 100. Therefore, the upper substrate 112 may be referred to as a second extended substrate.

[0106] Furthermore, a filling layer 190 may be placed on the front surface of the lower substrate 111 to fill the space between the upper substrate 112 and the components placed on the lower substrate 111. The filling layer 190 may be made of a curable adhesive. Specifically, the material constituting the filling layer 190 can be coated onto the front surface of the lower substrate 111 and then cured to form the filling layer 190 between the upper substrate 112 and the components placed on the lower substrate 111. For example, the filling layer 190 may be an optically clear adhesive (OCA), and may be made of an acrylic adhesive, a silicone adhesive, a urethane adhesive, or the like.

[0107] Furthermore, referring to Figure 2, the touch panel 200 may include a material that can accommodate the extension of the display panel 100. The touch panel 200 is positioned above the display panel 100 and may have a shape corresponding to the display panel 100, for example, a shape corresponding to the lower substrate 111 that supports the display panel 100.

[0108] For example, the touch panel 200 may include a base substrate (or touch base substrate), a plurality of touch-sensing films arranged on the base substrate, a plurality of touch wires arranged in different directions on the base substrate and the plurality of touch-sensing films, a plurality of routing wires connected to the plurality of touch wires to transmit touch signals detected by the plurality of touch wires, and a plurality of link wires connecting the plurality of routing wires to the touch circuit section.

[0109] The base substrate can support multiple touch-sensing films, multiple touch wirings, multiple routing wirings, and multiple link wirings. The base substrate may be a ductile substrate that is reversibly capable of expansion and contraction.

[0110] Multiple touch-sensitive films may be arranged on the active region AA of the base substrate, spaced apart from each other by a certain distance. In one embodiment, the size of each of the multiple touch-sensitive films may correspond to the size of each of the multiple first plate patterns 121 arranged on the display panel 100 described with reference to Figure 3. In one embodiment, the multiple touch-sensitive films may include touch-sensitive material. For example, the multiple touch-sensitive films may include, but are not limited to, a touch-base film made of a flexible and stretchable insulating material and touch-sensitive material dispersed in particulate form within the touch-base film.

[0111] Multiple touch wirings for sensing touch may be arranged at the bottom and top of the touch-sensitive film.

[0112] Multiple touch wirings may include multiple first touch wirings arranged in a first direction X on the active region AA of the base substrate, and multiple second touch wirings arranged in a second direction Y so as to intersect the multiple first touch wirings with a touch-sensing film in between. The region where the multiple first touch wirings and the multiple second touch wirings intersect is defined as a touch-sensing region, and multiple touch-sensing films may be arranged superimposed on the touch-sensing region. This allows the touch panel 200 to sense touch coordinates and touch pressure by utilizing the change in resistance of the touch-sensing film in response to touch input.

[0113] Multiple touch wiring may have a linear shape in areas where it overlaps with multiple touch-sensing films (e.g., touch-sensing areas), and a curved shape in other areas.

[0114] Thus, by arranging multiple touch-sensing films of the touch panel 200 of the display panel 100 according to an embodiment of the present invention on a flexible substrate, such as a base substrate, so as to be separated from each other, and by placing them in an area that overlaps with the first plate pattern 121 of the display panel 100, when the display panel 100 is stretched in both directions, the touch panel 200 may also be able to be stretched in both directions.

[0115] Multiple routing lines may be arranged on the inactive region NA of the base board and connected to multiple touch lines arranged in the active region AA. This allows touch signals detected by the multiple touch lines to be transmitted to the multiple routing lines.

[0116] Multiple routing wires may have a bent shape to ensure the stretchability of the touch panel 200.

[0117] Multiple link wires can electrically connect multiple routing wires and touch circuit sections. This allows touch signals detected from multiple touch wires and transmitted to multiple routing wires to be transmitted to the touch circuit section through the multiple link wires. Thus, the touch circuit section can detect touch input from an external source (e.g., user touch).

[0118] Referring to Figure 2, the display device 1000 of the present invention includes a first cover substrate CS1, a second cover substrate CS2, a third cover substrate CS3, a display panel 100, and a touch panel 200. Further referring to Figure 5, each cover substrate CS1, CS2, and CS3 has a structure in which the tensile modulus is higher than that of the upper substrate 112 and lower substrate 111 of the display panel 100. For example, the tensile modulus of the cover substrates CS1, CS2, and CS3 may be 1 MPa or higher, while the tensile modulus of the upper substrate 112 and lower substrate 111 may be less than 1 MPa. Such a configuration protects the internal components of the display device 1000 and provides structural stability.

[0119] Referring to Figure 6, the display panel 100 is divided into a non-stretched region where the first plate pattern 121, on which the pixels are located, is arranged, and a stretched region where the first or second connecting wiring 182 is arranged. The non-stretched region maintains a stable shape with no change in stretched length between the non-stretched and stretched states. In contrast, the stretched region exhibits a difference in stretched length between the non-stretched and stretched states, embodying the stretchable characteristics of the display panel 100.

[0120] Since each cover substrate CS1, CS2, and CS3 has a structure in which the tensile modulus of elasticity is higher than that of the upper substrate 112 and lower substrate 111 of the display panel 100, the elongation rate of the stretched region can be limited. For example, the stretched region 182 has an elongation rate of approximately 140%, and the elongation rate of the display panel 100 is designed to be approximately 120%, ensuring stable performance even with mechanical deformation.

[0121] To reiterate, the high tensile moduli of the first cover substrate CS1, the second cover substrate CS2, and the third cover substrate CS3 effectively protect each component of the display device 1000 from external shocks and deformation. Such stability enhances the durability of the device and contributes to increased reliability during long-term use.

[0122] By limiting the stretching rate of the stretched area to approximately 140%, the display device 1000 can be controlled to prevent damage due to excessive deformation. This is a core element of the stretchable display, ensuring stable performance and a long lifespan.

[0123] By setting the overall elongation ratio to approximately 120%, the display device 1000 provides flexibility and reliability suitable for deformable electronic devices such as wearable devices. This ensures consistent performance of the display device 1000 and allows it to be applied to various forms according to user requirements.

[0124] In conclusion, the display device 1000 of the present invention simultaneously embodies structural stability, stretchability, and durability through the control of the cover substrates CS1, CS2, and CS3 with high tensile modulus and the stretched region 182. Through this, it can provide optimal performance and reliability in various application fields such as wearable devices.

[0125] Figure 7a is a graph showing the relationship between tensile strain and tensile strength of the first cover substrate during tension and contraction.

[0126] Figure 7b is a graph showing the relationship between tensile strain and tensile strength of the second cover substrate during tension and contraction.

[0127] The display device 1000 of the present invention was designed based on the tensile strain characteristics and tensile strength of the first cover substrate CS1 and the second cover substrate CS2 during tension and contraction, respectively.

[0128] Specifically, in order for the overall elongation ratio to be set to approximately 120%, the amount of hysteresis change affecting the elastic restoring force of the first cover substrate CS1 and the second cover substrate CS2 during tension and contraction may be within 2%. Specifically, if the amount of hysteresis change of each of the first cover substrate CS1 and the second cover substrate CS2 is high, it may mean that the elastic restoring force when the first cover substrate CS1 and the second cover substrate CS2 are stretched and contracted will decrease. For example, if the amount of hysteresis change of each of the first cover substrate CS1 and the second cover substrate CS2 is 2% or more, when the display device 1000 of the present invention is stretched repeatedly, the first cover substrate CS1 and the second cover substrate CS2 may not be able to contract completely, which may cause deformation or cracking of the connecting wiring. Therefore, the amount of hysteresis change of each of the first cover substrate CS1 and the second cover substrate CS2 of the display device 1000 of the present invention must be 2% or less.

[0129] The tensile modulus of the first cover substrate CS1 may be higher than that of the second cover substrate CS2. Furthermore, the tensile modulus of the first cover substrate CS1 and the tensile modulus of the second cover substrate CS2 may be between 3.0 MPa and 7.0 MPa.

[0130] Based on this premise, referring to Figure 7a, as shown by the dotted line, the degree of tensile strain increases as the tensile strength of the first cover substrate CS1 increases during tension. Specifically, the tensile strength increases from 0 MPa to 1.2 MPa or higher during tension, and this can increase the degree of tensile strain to 30%. Conversely, referring to Figure 7a, as shown by the solid line, the degree of tensile strain decreases as the tensile strength of the first cover substrate CS1 decreases during contraction. Specifically, the tensile strength decreases from 1.2 MPa or higher to 0 MPa during tension, and this can gradually decrease the degree of tensile strain. However, as shown in Figure 7a, even if the tensile strength becomes 0 MPa during contraction, the degree of tensile strain does not become 0%, but can recover to a state of elongation of 1.76%. That is, it does not recover to the original degree of tensile strain, but can recover to a state of elongation of 1.76%. Therefore, the amount of hysteresis change for each of the first cover substrates CS1 can be 1.76%.

[0131] Referring to Figure 7b, as shown by the dotted line, the degree of tensile strain increases as the tensile strength of the second cover substrate CS2 increases during tension. Specifically, the tensile strength increases from 0 MPa to 1.2 MPa or higher during tension, and this can increase the degree of tensile strain to 30%. Conversely, referring to Figure 7b, as shown by the solid line, the degree of tensile strain decreases as the tensile strength of the second cover substrate CS2 decreases during contraction. Specifically, the tensile strength decreases from 1.2 MPa or higher to 0 MPa during tension, and this can gradually decrease the degree of tensile strain. However, as shown in Figure 7b, even if the tensile strength becomes 0 MPa during contraction, the degree of tensile strain does not become 0%, but can recover to a state of elongation of 1.2%. That is, it does not recover to the original degree of tensile strain, but can recover to a state of elongation of 1.2%. Therefore, the change in hysteresis of the second cover substrate CS2 can be 1.2%.

[0132] As mentioned above, the tensile modulus of the first cover substrate CS1 is higher than that of the second cover substrate CS2, so the change in hysteresis of the second cover substrate CS2 may be lower than that of the second cover substrate CS2. Furthermore, since the change in hysteresis of both the first cover substrate CS1 and the second cover substrate CS2 is 2% or less, the tensile modulus of the first cover substrate CS1 and the tensile modulus of the second cover substrate CS2 may be between 3.0 MPa and 7.0 MPa. Specifically, the tensile modulus of the first cover substrate CS1 may be between 4.0 MPa and 7.0 MPa, and the tensile modulus of the second cover substrate CS2 may be between 3.0 MPa and 5.5 MPa.

[0133] Figure 8 shows the neutral plane of the display device.

[0134] Furthermore, as mentioned above, since the tensile modulus of the first cover substrate CS1 is higher than that of the second cover substrate CS2, the neutral surface of the display device 1000 can be located inside the display panel 100, as shown in Figure 8.

[0135] Specifically, the neutral plane refers to the cross-section where, when external forces act on a structure, tensile and compressive forces are balanced, resulting in zero stress. This cross-section plays a crucial role in minimizing deformation within the structure and maintaining structural stability. The display device 1000 shown in Figure 8 illustrates a structure designed to optimize the position of such a neutral plane.

[0136] The first cover substrate CS1 is designed to have a higher tensile modulus than the second cover substrate CS2. Tensile modulus is a physical attribute that indicates how well a material can resist deformation under external forces; materials with a high tensile modulus have greater resistance to deformation. The high tensile modulus of the first cover substrate CS1 is the main factor that causes the neutral plane to move toward the substrate. As a result, the neutral plane is formed away from the relatively less rigid second cover substrate CS2 and adjacent to the first cover substrate CS1.

[0137] The neutral plane is designed to overlap with the interior of the display panel 100, specifically the region where the light-emitting elements (e.g., organic light-emitting diodes, OLEDs) and transistors (e.g., thin-film transistors, TFTs) are located. By positioning the main components of the display panel 100 close to the neutral plane, the tensile and compressive stresses experienced by these components are minimized even when structural deformation occurs due to external forces (e.g., bending, stretching, etc.).

[0138] The technical advantages of this design can be explained as follows: When repeated stretching or bending deformation is applied, the light-emitting elements and transistors located inside the display panel 100 are protected from stresses generated by the external force. Since little deformation occurs near the neutral plane, the possibility of physical damage to the light-emitting elements and transistors located in this region is significantly reduced. This prevents problems such as cracking of the light-emitting elements, disconnection of electrodes, degradation of transistor characteristics, and delamination, thus preventing a decrease in the performance of the display panel 100.

[0139] Transistors are essential components for controlling electrical signals. If the neutral plane design is misaligned, deformation patterns will occur unevenly on one side, leading to physical damage, changes in circuit resistance, and even fracture. This can degrade the overall electrical characteristics of the display panel. To prevent such problems, this display device 1000 employs a structure that precisely aligns the neutral plane with the main components of the display panel 100.

[0140] In conclusion, the display device 1000 utilizes the high tensile modulus of the first cover substrate CS1 to guide the neutral plane into the interior of the display panel 100, thereby effectively protecting the light-emitting elements and transistors from deformation and stress. Such a design ensures the long-term stability and reliability of the display device and possesses important technical features that provide excellent performance and durability, especially in application fields such as flexible displays.

[0141] Furthermore, the third cover substrate CS3 has a lower tensile modulus than the second cover substrate CS2, and this characteristic is designed to perform a specific function as the upper protective layer of the display device 1000. For example, the third cover substrate CS3 can have a low tensile modulus of 0.75 MPa to 1.5 MPa, and such a low tensile modulus increases the flexibility of the third cover substrate CS3, allowing it to effectively absorb and mitigate mechanical stress generated by external impacts and deformation conditions.

[0142] The third cover substrate CS3 is positioned at the upper end of the display device 1000 and bonded to the touch panel 200 through optical adhesive OCA. Having a low tensile modulus, the third cover substrate CS3 maintains the functionality of the touch panel 200 and protects the device from external impacts and scratches. Furthermore, the third cover substrate CS3 is composed of a highly transparent polymer film or ductile material, ensuring that it does not affect the optical performance of the display and maintains touch sensitivity and accuracy.

[0143] The following describes a display device according to another embodiment of the present invention. The only difference between the display device according to one embodiment of the present invention and the display device according to the other embodiment of the present invention is the presence or absence of a cover coating layer, which will be explained in detail below.

[0144] Figure 9 is a cross-sectional view of a display device according to another embodiment of the present invention.

[0145] Referring to Figure 9, the display device 2000 according to another embodiment of the present invention may further include at least one cover coating layer CT1, CT2 on the outer surface of at least one cover substrate CS1, CS2. The coefficient of friction of the at least one cover coating layer CT1, CT2 may be lower than the coefficient of friction of the at least one cover substrate CS1, CS2.

[0146] The first cover coating layer CT1 is positioned at the bottom of the display device 2000 and is formed on the lower outer surface of the first cover substrate CS1. The first cover coating layer CT1 contains reactive nano cross linkers, and the frictional resistance coefficient can be optimized by adjusting the content and type of nano cross linkers. This provides stable slip characteristics at the bottom of the display device 2000, improving stability during device movement and use.

[0147] The material of the first cover coating layer CT1 is composed of a polymer substrate material with low friction properties, to which a reactive nano cross linker is added for reinforcement. The nano cross linker forms chemical bonds within the polymer network to improve the structural stability and durability of the material. Typically, silicon polymers, fluorine-based coating agents, or UV-curable polyurethanes can be used. Such materials provide low surface energy to reduce frictional resistance while maintaining mechanical strength and durability.

[0148] The first cover coating layer CT1 improves the lower slip characteristics, enabling the display device 2000 to operate stably on various surfaces. Low frictional resistance enhances the mobility and handling convenience of the device and prevents damage from surface contact. Furthermore, structural reinforcement utilizing a nano cross linker ensures that the slip characteristics are maintained even during prolonged use of the device, providing both durability and reliability.

[0149] The second cover coating layer CT2 is located at the uppermost end of the display device 2000 and is formed on the upper outer surface of the second cover substrate CS2. The second cover coating layer CT2 optimizes the frictional resistance coefficient of the upper surface by adjusting the content and type of reactive nano cross linker, improving slip characteristics and enhancing the adaptability of the device to the external environment. In addition, the second cover coating layer CT2 provides a function to protect the device from scratches and external impacts.

[0150] The second cover coating layer CT2 is composed of a high-performance material that provides both transparency and durability, and includes a reactive nano cross linker. The main materials that can be used are silicon-based coating agents, UV-curable polyurethanes, or fluoropolymers (e.g., PTFE, fluororesins). In particular, polymers with self-healing properties may be introduced to allow for recovery when micro-scratches or damage occur. The nano cross linker plays a role in increasing the chemical bonding strength of the coating layer, thereby enhancing durability and surface stability.

[0151] The second cover coating layer CT2 improves the slip properties on the upper surface, providing resistance to external impacts and scratches. This maintains the surface condition of the display device 2000 during prolonged use and provides high sensitivity and accuracy during user touch input. Furthermore, the low frictional resistance improves the operability of the device's upper surface and enhances its durability in external environments. The introduction of self-healing materials offers further advantages, such as extending the device's lifespan and reducing maintenance costs.

[0152] At least one cover coating layer CT1, CT2 enhances the external protection function of the display device 2000, and acts as an important component that simultaneously provides tacki-less and slip properties and durability to reduce surface stickiness and meet the performance requirements of next-generation display environments.

[0153] The following describes a display device according to one embodiment of the present invention and other embodiments. The display device according to one embodiment of the present invention and the display device according to other embodiments of the present invention differ only in the cover substrate, so this will be explained in detail.

[0154] Figure 10 is a schematic plan view showing a display device according to an embodiment of the present invention.

[0155] Figure 11 is a cross-sectional view taken along the line X-X' shown in Figure 10.

[0156] As shown in Figures 10 and 11, the display device 3000 according to another embodiment of the present invention includes a fourth cover substrate CS4, the fourth cover substrate CS4 enhancing the external protection and structural stability of the display device 3000 through its property of having a higher tensile modulus than the first cover substrate CS1'. The sizes of the first cover substrate CS1' and the second cover substrate CS2' of the display device 3000 according to another embodiment of the present invention may be the same as, but are not limited to, the sizes of the display panel 100 and the touch panel 200.

[0157] Specifically, the fourth cover substrate CS4 is positioned on the upper and lower outer casings of the display device 3000 and protects the internal components (display panel 100, touch panel 200, first cover substrate CS1', ​​second cover substrate CS2', and third cover substrate CS3) from impacts, pressure, and environmental factors originating from outside the device. It also complements the overall rigidity of the device through its high tensile modulus and maintains the mechanical stability of the device.

[0158] More specifically, the fourth cover substrate CS4 is located on the outer periphery of the second cover substrate CS2' at the upper end of the display device 3000 and is bonded to these substrates through optical adhesive OCA. This reinforces the superstructure and minimizes mechanical damage when external impacts occur at the top. The fourth cover substrate CS4 is also located on the outer periphery of the first cover substrate CS1' at the lower end of the display device 3000 and is bonded to the internal components through optical adhesive OCA. At the lower end, it maintains the stability of the device and protects the lower part from mechanical impacts and friction generated in the external environment. As seen in Figure 10, the fourth cover substrate CS4 is positioned not only at the upper and lower ends of the device but also at the left and right edges of the device, designed to enclose the overall structure of the display device 3000. Such placement also allows for protection against external impacts from the sides.

[0159] The fourth cover substrate CS4 can be constructed from a material with excellent durability and strength, and commonly used materials include tempered glass, ceramic, or high-strength polymers (e.g., polycarbonate). In addition, scratch-resistant and anti-fouling coatings may be added to enhance surface properties. In particular, the fourth cover substrate CS4 utilizes a material with a high tensile modulus (e.g., 7 MPa) to maximize resistance to mechanical impact.

[0160] The fourth cover substrate CS4 significantly improves the structural stability of the display device 3000 through its high tensile modulus. It prevents damage from external shocks and pressures, extending the lifespan of internal components. It also evenly distributes the load on the device, minimizing mechanical deformation and ensuring stable operation.

[0161] The outer protection function of the fourth cover substrate CS4 is particularly suitable for devices that are frequently exposed to the external environment, such as wearable devices, and greatly improves the reliability and durability of the device. Furthermore, it perfectly secures each component through bonding with the optical adhesive OCA, maintaining structural integrity.

[0162] Therefore, the display device 3000 according to yet another embodiment of the present invention ensures the resistance of the display device 3000 to external impacts and environmental factors based on its high tensile modulus and durability, and acts as an essential protective component suitable for next-generation display and wearable technologies.

[0163] Display devices according to various embodiments of the present invention can be described as follows.

[0164] To solve the problems described above, a display device according to one embodiment of the present invention includes a display panel comprising a first stretched substrate, a plurality of subpixels spaced apart from each other on the first stretched substrate, a plurality of stretchable connecting wires connecting the subpixels, and a second stretched substrate, and at least one cover substrate disposed outside the display panel, characterized in that the tensile modulus of the cover substrate is higher than the tensile modulus of the first stretched substrate and the tensile modulus of the second stretched substrate.

[0165] According to another feature of the present invention, the present invention includes a touch panel disposed on a display panel, a first cover substrate disposed on the lower surface of the display panel, and a second cover substrate disposed on the touch panel, characterized in that the tensile modulus of the first cover substrate is higher than that of the second cover substrate.

[0166] Another feature of the present invention is that at least one cover substrate has a tensile modulus of 3.0 MPa to 7.0 MPa.

[0167] Another feature of the present invention is that at least one cover coating layer is disposed on the outer surface of at least one cover substrate, and the coefficient of friction of the cover coating layer is lower than the coefficient of friction of the cover substrate.

[0168] Another feature of the present invention is that the cover coating layer includes a first cover coating layer disposed on the outer surface of a first cover substrate and a second cover coating layer disposed on the outer surface of a second cover substrate.

[0169] Another feature of the present invention is that at least one cover substrate is provided, and a third cover substrate is disposed between the touch panel and the second cover substrate, wherein the tensile modulus of the third cover substrate is lower than that of the second cover substrate.

[0170] Another feature of the present invention is that at least one cover substrate includes a plurality of fourth cover substrates in contact with the outer region of the first cover substrate and the outer region of the second cover substrate, and the tensile modulus of the fourth cover substrate is higher than that of the first cover substrate.

[0171] Another feature of the present invention is that the neutral surface of the display device is located on the display panel.

[0172] According to another feature of the present invention, the fourth cover substrate is arranged on the left and right edges of the display device.

[0173] According to another feature of the present invention, at least one cover coating layer is characterized by containing a reactive nanocrosslinking agent.

[0174] Another feature of the present invention is that the tensile modulus of the first stretched substrate and the tensile modulus of the second stretched substrate are 1 MPa or less.

[0175] According to another feature of the present invention, the neutral surface of the display device is located inside the display panel.

[0176] Another embodiment of the present invention includes a first cover substrate, a stretchable display panel, a stretchable touch panel on the stretchable display panel, and a second cover substrate on the stretchable touch panel, characterized in that the tensile modulus of the first cover substrate and the second cover substrate is higher than the tensile modulus of the stretched substrate included in the stretchable display panel.

[0177] Another feature of the present invention is that the tensile modulus of the first cover substrate and the second cover substrate is 3.0 MPa to 7.0 MPa.

[0178] Another feature of the present invention is that it includes a first cover coating layer located beneath a first cover substrate and a second cover coating layer placed on top of a second cover substrate, wherein the coefficient of friction of the first cover coating layer and the second cover coating layer is lower than the coefficient of friction of the cover substrate.

[0179] Another feature of the present invention is that it includes a third cover substrate disposed between a stretchable touch panel and a second cover substrate, wherein the tensile modulus of the third cover substrate is lower than that of the second cover substrate.

[0180] Another feature of the present invention is that it includes a frame for a first cover substrate and a plurality of fourth cover substrates in contact with the frame for a second cover substrate, wherein the tensile modulus of the fourth cover substrate is higher than that of the first cover substrate.

[0181] Another feature of the present invention is that the neutral surface of the display device is located on a light-emitting element and a driving element included in a stretchable display panel.

[0182] According to another feature of the present invention, the first cover coating layer and the second cover coating layer are characterized by containing a reactive nanocrosslinking agent.

[0183] Another feature of the present invention is that the tensile modulus of the stretched substrate is 1 MPa or less.

[0184] According to another feature of the present invention, the neutral surface of the display device is located inside the display panel.

[0185] A display device according to yet another embodiment of the present invention includes a first cover substrate, a display panel disposed on the first cover substrate, the display panel including a first stretched substrate, a plurality of subpixels disposed on the first stretched substrate, a plurality of stretchable connecting lines connecting the plurality of subpixels, and a second stretched substrate disposed on the plurality of subpixels and the plurality of connecting lines, a second cover substrate disposed on the display panel, and a third cover substrate disposed between the display panel and the second cover substrate, wherein the planar area of ​​the first cover substrate and the planar area of ​​the second cover substrate are each larger than the planar area of ​​the third cover substrate.

[0186] Another feature of the present invention is that the size of the first cover substrate and the size of the second cover substrate are each larger than the size of the third cover substrate.

[0187] Another feature of the present invention is that the tensile modulus of the first cover substrate and the tensile modulus of the second cover substrate are each greater than the tensile modulus of the third cover substrate.

[0188] Another feature of the present invention is that it further includes a fourth cover substrate which is disposed in the peripheral region of the first cover substrate or the second cover substrate, or which is disposed in the peripheral regions of the first cover substrate and the second cover substrate, respectively.

[0189] Another feature of the present invention is that, in the plan view, the fourth cover substrate is superimposed on the third cover substrate.

[0190] According to another feature of the present invention, the fourth cover substrate is characterized in that it has a tensile modulus greater than that of the third cover substrate.

[0191] According to another feature of the present invention, in a plan view, the first cover substrate and the second cover substrate each extend beyond the peripheral area of ​​the display panel.

[0192] According to another feature of the present invention, in a plan view, the size of the third cover substrate corresponds to the size of the display panel.

[0193] Another feature of the present invention is that it further comprises a first optical adhesive between the first cover substrate and the display panel and a second optical adhesive between the second cover substrate and the third cover substrate.

[0194] According to another feature of the present invention, at least one of the first cover substrate and the second cover substrate includes a coating layer disposed on its outer surface, and the coating layer is a polymer containing a reactive nanocrosslinking agent.

[0195] Another feature of the present invention is that the first stretched substrate and the second stretched substrate each have a tensile modulus lower than that of the first cover substrate and the second cover substrate.

[0196] Another feature of the present invention is that the neutral surface formed when the display device is bent passes through the display panel in the thickness direction.

[0197] Although embodiments of the present invention have been described in further detail, the present invention is not necessarily limited to such embodiments and can be modified and implemented in various ways without deviating from the technical concept of the present invention. Accordingly, the embodiments disclosed herein are for illustrative purposes only, not to limit the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. The scope of protection of the present invention should be interpreted by the following claims, and all technical concepts within an equivalent scope should be interpreted as being included in the scope of the rights of the present invention.

Claims

1. A display panel including a first stretched substrate, a plurality of subpixels spaced apart from each other on the first stretched substrate, a plurality of stretchable connecting wires connecting the subpixels, and a second stretched substrate disposed on the plurality of subpixels and the plurality of connecting wires, and At least one cover substrate located on the outside of the display panel. Includes, A display device wherein the tensile modulus of at least one cover substrate is higher than the tensile modulus of the first stretched substrate and the tensile modulus of the second stretched substrate.

2. The system further includes a touch panel placed on the display panel, The at least one cover substrate includes a first cover substrate disposed on the lower surface of the display panel and a second cover substrate disposed on the touch panel. The display device according to claim 1, wherein the tensile modulus of the first cover substrate is higher than the tensile modulus of the second cover substrate.

3. The display device according to claim 1, wherein the tensile modulus of at least one cover substrate is 3.0 MPa to 7.0 MPa.

4. At least one cover coating layer is disposed on the outer surface of the at least one cover substrate. The display device according to claim 2, wherein the coefficient of friction of the at least one cover coating layer is lower than the coefficient of friction of the at least one cover substrate.

5. The at least one cover coating layer is A first cover coating layer disposed on the outer surface of the first cover substrate, and The display device according to claim 4, further comprising a second cover coating layer disposed on the outer surface of the second cover substrate.

6. The at least one cover substrate further includes a third cover substrate disposed between the touch panel and the second cover substrate, The display device according to claim 2, wherein the tensile modulus of the third cover substrate is lower than the tensile modulus of the second cover substrate.

7. The at least one cover substrate further includes a plurality of fourth cover substrates that are in contact with the outer region of the first cover substrate and the outer region of the second cover substrate. The display device according to claim 2, wherein the tensile modulus of the fourth cover substrate is higher than the tensile modulus of the first cover substrate.

8. The display device according to claim 7, wherein the fourth cover substrate is arranged on the left edge and the right edge of the display device.

9. The display device according to claim 4, wherein the at least one cover coating layer comprises a reactive nanocrosslinking agent.

10. The display device according to claim 1, wherein the tensile modulus of the first stretched substrate and the tensile modulus of the second stretched substrate are 1 MPa or less.

11. The display device according to claim 2, wherein the neutral surface of the display device is located inside the display panel.

12. First cover substrate, A stretchable display panel, which is disposed on the first cover substrate, A stretchable touch panel, which is placed on the stretchable display panel, and A second cover substrate is placed on the stretchable touch panel. Includes, A display device wherein the tensile modulus of the first cover substrate and the tensile modulus of the second cover substrate are higher than the tensile modulus of the stretched substrate included in the stretchable display panel.

13. The display device according to claim 12, wherein the tensile modulus of the first cover substrate and the tensile modulus of the second cover substrate are 3.0 MPa to 7.0 MPa.

14. The first cover coating layer located beneath the first cover substrate, and The second cover coating layer is placed on the second cover substrate. It further includes, The display device according to claim 12, wherein the coefficient of friction of the first cover coating layer and the coefficient of friction of the second cover coating layer are each lower than the coefficient of friction of the first cover substrate and the coefficient of friction of the second cover substrate.

15. The system further includes a third cover substrate disposed between the stretchable touch panel and the second cover substrate, The display device according to claim 12, wherein the tensile modulus of the third cover substrate is lower than the tensile modulus of the second cover substrate.

16. The present invention further includes a plurality of fourth cover substrates that are in contact with the edges of the first cover substrate and the edges of the second cover substrate, The display device according to claim 12, wherein the tensile modulus of the fourth cover substrate is higher than the tensile modulus of the first cover substrate.

17. The display device according to claim 14, wherein the first cover coating layer and the second cover coating layer contain a reactive nanocrosslinking agent.

18. The display device according to claim 12, wherein the tensile modulus of the stretched substrate is 1 MPa or less.

19. The display device according to claim 12, wherein the neutral surface of the display device is located inside the stretchable display panel.

20. First cover substrate, A display panel disposed on the first cover substrate, comprising a first stretched substrate, a plurality of subpixels disposed on the first stretched substrate, a plurality of stretchable connecting lines connecting the plurality of subpixels, and a second stretched substrate disposed on the plurality of subpixels and the plurality of connecting lines. The second cover substrate arranged on the display panel, and A third cover substrate is disposed between the display panel and the second cover substrate. Includes, A display device in which the planar area of ​​the first cover substrate and the planar area of ​​the second cover substrate are each larger than the planar area of ​​the third cover substrate.

21. The display device according to claim 20, wherein the size of the first cover substrate and the size of the second cover substrate are each larger than the size of the third cover substrate.

22. The display device according to claim 20, wherein the tensile modulus of the first cover substrate and the tensile modulus of the second cover substrate are each greater than the tensile modulus of the third cover substrate.

23. The display device according to claim 20, further comprising a fourth cover substrate disposed in the peripheral region of the first cover substrate or the second cover substrate, or disposed in the peripheral regions of the first cover substrate and the second cover substrate, respectively.

24. The display device according to claim 23, wherein in a plan view, the fourth cover substrate is superimposed on the third cover substrate.

25. The display device according to claim 23, wherein the fourth cover substrate has a tensile modulus greater than that of the third cover substrate.

26. The display device according to claim 20, wherein, in a plan view, the first cover substrate and the second cover substrate each extend beyond the peripheral area of ​​the display panel.

27. The display device according to claim 20, wherein, in a plan view, the size of the third cover substrate corresponds to the size of the display panel.

28. The first optical adhesive between the first cover substrate and the display panel, and The display device according to claim 20, further comprising a second optical adhesive between the second cover substrate and the third cover substrate.

29. At least one of the first cover substrate and the second cover substrate includes a coating layer disposed on its outer surface. The display device according to claim 20, wherein the coating layer is a polymer containing a reactive nanocrosslinking agent.

30. The display device according to claim 20, wherein the first stretched substrate and the second stretched substrate each have a tensile modulus lower than that of the first cover substrate and the second cover substrate.

31. The display device according to claim 20, wherein the neutral surface formed when the display device is bent passes through the display panel in the thickness direction.

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