Display device

Abstract

The invention discloses a display device which has a first display state and a second display state and comprises a display layer, a soft material layer and an adhesion layer. When the display device is in the second display state, the display layer has a larger display area than when the display device is in the first display state. The display layer comprises a substrate, a light-emitting structure, an insulating layer and a touch element. The light-emitting structure is arranged on the substrate, the insulating layer is arranged on the substrate, and the touch element is arranged between the light-emitting structure and the insulating layer. The adhesive layer is attached between the insulating layer and the soft material layer of the display layer, and the edge of the adhesive layer is arc-shaped in a profile map.

Description

[0001] This application is a divisional application of the invention patent application with the application date of June 1, 2021, the application number of 202110610139.8, and the invention name of "Rollable Display Device". Technical Field

[0002] The present invention relates to a rollable display device, and particularly to a rollable display device having an optical layer. Background Art

[0003] In recent years, rollable display devices or deformable display devices have become one of the focuses of new-generation electronic technologies. Generally, the area of the display region of a rollable display device or a deformable display device can be changed by curling, but the stress generated during the process of extension and / or contraction of its structure will affect the display performance or cause damage to the display device. Therefore, manufacturers need to develop appropriate structural designs to reduce the problems caused by stress. Summary of the Invention

[0004] An embodiment of the present invention provides a display device having a first display state and a second display state. The display device includes a display layer, a flexible material layer, and an adhesive layer. When the display device is in the second display state, the display layer has a larger display area than in the first display state. The display layer includes a substrate, a light-emitting structure, an insulating layer, and a touch control element. The light-emitting structure is disposed on the substrate, the insulating layer is disposed on the substrate, and the touch control element is disposed between the light-emitting structure and the insulating layer. The adhesive layer is attached between the insulating layer of the display layer and the flexible material layer, wherein in a cross-sectional view, the edge of the adhesive layer has an arc shape. Description of the Drawings

[0005] Figure 1 It is a top view schematic diagram of the rollable display device according to an embodiment of the present invention in different states.

[0006] Figure 2 It is a cross-sectional view schematic diagram of the rollable display device according to an embodiment of the present invention in a general display state.

[0007] Figure 3 It is a cross-sectional view schematic diagram of the rollable display device according to an embodiment of the present invention in an extended display state.

[0008] Figure 4 It is a partial enlarged cross-sectional view schematic diagram of the rollable display device according to the first embodiment of the present invention.

[0009] Figure 5 It is a partial enlarged cross-sectional view schematic diagram of the rollable display device according to the second embodiment of the present invention.

[0010] Figure 6Schematic cross-sectional view of the optical layer of a rollable display device according to an embodiment of the present invention.

[0011] Figure 7 Partial enlarged cross-sectional view of a rollable display device according to the third embodiment of the present invention.

[0012] Figure 8 Schematic process diagram of attaching an optical layer of a rollable display device to a display layer through an adhesive layer according to an embodiment of the present invention.

[0013] Figure 9 Partial enlarged cross-sectional view of the display layer, adhesive layer, and optical layer of a rollable display device according to an embodiment of the present invention.

[0014] Figure 10 Schematic depiction of a partial cross-section of a rollable display device according to an embodiment of the present invention.

[0015] Description of reference numerals: 100, 100a, 100b, 100c - rollable display device; 102 - rotating element; 110 - support structure; 112 - support plate; 114, 122, 220 - adhesive layer; 120 - cover layer; 120a - first cover layer; 120b - second cover layer; 130 - signal pad; 140 - circuit board; 200 - display layer; 202, 204 - end; 210, 230 - substrate; 240, 264, 290, 292 - insulating layer; 250 - circuit layer; 252 - thin film transistor; 252C - channel layer; 252G - gate; 252S - source; 252D - drain; 252I - gate insulating layer; 260 - light emitting structure; 262 - light emitting element; 262a - lower electrode; 262b, 262d - light emitting layer; 262c - upper electrode; 270 - encapsulation layer; 280 - touch layer; 282 - touch element; 284, 289 - conductive layer; 300 - optical layer; 300e, 400e, 320e, 310e - edge; 310 - base layer; 320 - functional layer; 322 - polarization layer; 324 - retardation layer; 330 - intermediate layer; 400 - adhesive layer; D1 - first direction; D - distance; X - extension direction; DR - display area; I - general display state; II - extended display state; R - radius of curvature; R1 - non-rollable area; R2 - rollable area; SB - substrate; T, Ta, Tb, T1, T2, T3, T4, T5 - thickness; VL - vertical line; L_310e, L_1 - extension line; WP - width; S1 - front side; S2 - back side; DS - display surface. Detailed Description of the Invention

[0016] The present invention can be understood by referring to the following detailed description and in conjunction with the accompanying drawings. It should be noted that, for the convenience of the reader's understanding and the simplicity of the drawings, only a part of the electronic device is shown in the multiple drawings of the present invention, and the specific elements in the drawings are not drawn to actual scale. In addition, the number and size of each element in the drawings are only for illustration and are not used to limit the scope of the present invention.

[0017] Throughout the specification and claims of the present invention, certain terms will be used to refer to specific elements. Those skilled in the art should understand that electronic device manufacturers may use different names to refer to the same element. This document is not intended to distinguish between elements that have the same function but different names. In the following specification and claims, words such as "comprising", "including", "having" are open-ended terms, and thus should be interpreted as meaning "including but not limited to...". Therefore, when the description of the present invention uses the terms "comprising", "including" and / or "having", it specifies the existence of the corresponding features, regions, steps, operations and / or components, but does not exclude the existence of one or more corresponding features, regions, steps, operations and / or components.

[0018] The directional terms mentioned herein, such as "up", "down", "front", "back", "left", "right", etc., are only with reference to the directions in the accompanying drawings. Therefore, the directional terms used are for illustration and not for limiting the present invention. In the accompanying drawings, each drawing shows the general features of the methods, structures and / or materials used in specific embodiments. However, these drawings should not be construed as defining or limiting the scope or nature covered by these embodiments. For example, for clarity, the relative sizes, thicknesses and positions of each film layer, region and / or structure may be reduced or enlarged.

[0019] When a corresponding component (such as a film layer or a region) is referred to as "on another component", it can be directly on another component, or there may be other components between the two. On the other hand, when a component is referred to as "directly on another component", there are no components between the two. In addition, when a component is referred to as "on another component", the two have an up-and-down relationship in the top view direction, and this component can be above or below another component, and this up-and-down relationship depends on the orientation of the device.

[0020] The terms "about", "equal to", "equivalent" or "the same", "substantially" or "approximately" are generally interpreted as within 20% of the given value or range, or within 10%, 5%, 3%, 2%, 1% or 0.5% of the given value or range.

[0021] The ordinal numbers used in the description and claims, such as "first", "second", etc., are used to modify elements, and they do not themselves imply or represent that the element (or elements) has any previous ordinal number, nor do they represent the order of one element and another element or the order in the manufacturing method. The use of these ordinal numbers is only to clearly distinguish an element with a certain name from another element with the same name. The terms used in the claims and the description may not be the same. Accordingly, the first component in the description may be the second component in the claim.

[0022] It should be noted that, without departing from the spirit of the present invention, the features in several different embodiments can be replaced, recombined, and mixed to complete other embodiments. As long as the features between the embodiments do not violate the spirit of the invention or conflict with each other, they can be arbitrarily mixed and used.

[0023] In the present invention, the thickness, length, and width can be measured by an optical microscope, and the thickness can be measured from the cross-sectional image in an electron microscope, but this is not limited thereto. In addition, there may be a certain error between any two values or directions used for comparison. If the first value is equal to the second value, it implies that there may be an error of about 10% between the first value and the second value; if the first direction is perpendicular to the second direction, the angle between the first direction and the second direction can be between 80 degrees and 100 degrees; if the first direction is parallel to the second direction, the angle between the first direction and the second direction can be between 0 degrees and 10 degrees.

[0024] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. It can be understood that these terms, such as those defined in a commonly used dictionary, should be interpreted as having a meaning consistent with the related technology and the background or context of the present invention, and should not be interpreted in an idealized or overly formal manner, unless specifically defined in the embodiments of the present invention.

[0025] Please refer to Figure 1 、 Figure 2 and Figure 3 。 Figure 1 is a top view schematic diagram of a rollable display device according to an embodiment of the present invention in different states. Figure 2 is a cross-sectional schematic diagram of a rollable display device according to an embodiment of the present invention in a general display state. Figure 3 is a cross-sectional schematic diagram of a rollable display device according to an embodiment of the present invention in an extended display state. As Figure 1 、 Figure 2 and Figure 3As shown, in the present invention, the rollable display device 100 has a general display state I and an extended display state II, and the rollable display device 100 includes a display layer 200 and an optical layer 300. In some embodiments, the optical layer 300 can be attached to the display layer 200 through an adhesive layer 400. The display layer 200 can include a display medium, such as including liquid crystal, light-emitting diode (LED), quantum dot (QD), fluorescence, or phosphor. The light-emitting diode can, for example, include an organic light-emitting diode (OLED), a mini LED, a micro LED, or a quantum dot light-emitting diode (QDLED, which can be, for example, a QDLED), but is not limited thereto.

[0026] In some embodiments, the display layer 200 has a display area DR, which is the area used to display the picture when the rollable display device 100 operates. By the folding or unfolding of the partially rollable display layer 200, the area of the display area DR can be changed. For example, the rollable display device 100 can have a non-rollable area R1 and a rollable area R2. The rollable area R2 is, for example, connected to one side of the non-rollable area R1. The area of the non-rollable area R1 remains fixed when viewed from the top-down direction, and the rollable area R2 can, for example, be folded or unfolded by a rotating element 102 (such as a rotating shaft or a roller) or other suitable elements, but is not limited thereto. In some embodiments, the area of the display area DR can, for example, change according to the folding or unfolding of the rollable area R2. In some embodiments, the state when the rollable area R2 of the rollable display device 100 is completely folded is defined as the general display state I, and the state when the rollable area R2 of the rollable display device 100 is at least partially unfolded is defined as the extended display state II. That is, the extended display state II includes aspects where the rollable area R2 is partially unfolded (as shown in the upper part), aspects where the rollable area R2 is mostly unfolded (as shown in the lower part), and aspects where the rollable area R2 is completely unfolded (not shown in the figure). When the rollable display device 100 is in the extended display state II, the display layer 200 can, for example, have a larger display area DR than in the general display state I. Figure 3 as shown in the upper part), aspects where the rollable area R2 is mostly unfolded (as shown in the lower part), Figure 3 and aspects where the rollable area R2 is completely unfolded (not shown in the figure). When the rollable display device 100 is in the extended display state II, the display layer 200 can, for example, have a larger display area DR than in the general display state I.

[0027] It should be noted that although the non-rollable area R1 is shown as a flat aspect in the drawings, in other embodiments (not shown), the non-rollable area R1 can be in a wavy or arc-edged aspect, but the area of this non-rollable area R1 remains fixed when viewed from the top-down direction.

[0028] It should be noted that the rollable display device 100 may optionally have a frame member (not shown) or a shielding element (not shown), and the frame member or the shielding element may optionally overlap or cover the rotating element 102 and / or a part of the display layer 200, and Figure 1 the change of the display area DR of the rollable display device 100 shown in the general display state I and the extended display state II may vary according to the condition of the display layer 200 shielded by the above frame member or the above shielding element, but when the rollable display device 100 is in the extended display state II, the display layer 200 can still have a larger display area DR than in the general display state I.

[0029] As Figure 2 and Figure 3 shown, in some embodiments, the rollable display device 100 may further include a support structure 110, a cover layer 120, a signal pad 130, and / or a circuit board 140 (such as a flexible circuit board or a rigid circuit board). In some embodiments, the display layer 200 may be disposed on the support structure 110, and the support structure 110 may be disposed on the back side S2 of the display layer 200 and in contact with the back side S2, but not limited thereto. In some embodiments (not shown), the display layer 200 and the support structure 110 may be adhered through an adhesive layer (not shown). In some embodiments, the optical layer 300 may be attached to the front side S1 of the display layer 200 through an adhesive layer 400, and the cover layer 120 may be disposed on the optical layer 300. In some embodiments, the material of the adhesive layer 400 may include UV glue, light-curable glue, optically clear adhesive (OCA), optically clear resin (OCR), thermosetting glue, moisture-curing glue, pressure sensitive adhesive (PSA), or other suitable glue or any combination of the above, but not limited thereto. In some embodiments, the material of the adhesive layer 400 may include acrylate or other suitable materials, but not limited thereto. In some embodiments, the display layer 200 may be disposed between the support structure 110 and the optical layer 300. In some embodiments, the optical layer 300 may be disposed between the display layer 200 and the cover layer 120.

[0030] In some embodiments, the display layer 200 may have ends 202 and 204 located on opposite sides. In some embodiments, the end 202 may be connected to and fixed to, for example, a portion of the display layer 200 located in the non-curling region R1. In some embodiments, the end 202 may be bent, for example, to the back side S2 of the display layer 200 and fixed to the support structure 110. In some embodiments, the end 202 may be fixed to the support structure 110 through, for example, an adhesive layer (not shown), but is not limited thereto. In some embodiments, the end 204 may be relative to the end 202, and the end 204 is located, for example, in the curling region R2. In some embodiments, the end 204 may be moved, for example, by the rotating element 102 or other suitable elements to close or unfold the curling region R2. In some embodiments, the end 204 may be moved to different positions according to different aspects of the extended display state II (such as Figure 3 the upper part and as Figure 3 the different aspects shown in the lower part). In some embodiments, the end 204 may be moved, for example, by the rotating element 102 or other suitable elements to change the distance D between the end 204 and the end 202. The distance D may be defined as the minimum distance between the end 204 and the end 202 in the extension direction X. In some embodiments, whether in the normal display state I or the extended display state II, the end 202 and / or the end 204 may be located, for example, on the side of the support structure 110 away from the display surface DS. In some embodiments, when the display area DR in the curling region R2 is fully unfolded (such as Figure 3 shown in the lower part), the end 204 of the display layer 200 may still be disposed under the support structure 110 so that a portion of the display layer 200 can be in a curled aspect. This design can make it easier when the fully unfolded curling region R2 needs to be closed again.

[0031] In some embodiments, the signal pad 130 may be disposed on the end 202, for example. The display layer 200 may be connected to the circuit board 140 through the signal pad 130, and signals are transmitted through the circuit board 140 to control the driving of the display layer 200, but is not limited thereto. In some embodiments, such as Figure 2As shown, since the signal pad 130 is disposed on the end portion 202, the signal pad 130 can be more firmly electrically connected to the circuit board 140, but not limited thereto. In some embodiments, the circuit board 140 can be disposed, for example, under the support structure 110 and can be selectively fixed to the support structure 110. In some embodiments, since the signal pad 130 is provided on the end portion 202 of the display layer 200 instead of being used for displaying an image, the optical layer 300, the adhesive layer 400, and / or the cover layer 120 can be selectively not provided or covered on the end portion 202, but not limited thereto. In some embodiments, an integrated circuit chip or a control unit can be selectively provided on the circuit board 140, but not limited thereto. In some embodiments (not shown), the circuit board 140 can be selectively removed, and the integrated circuit chip can be connected to the signal pad 130, for example, but not limited thereto. In some embodiments, since the end portion 204 of the display layer 200 may not be used for displaying an image, the optical layer 300, the adhesive layer 400, and / or the cover layer 120 can be selectively not provided on the end portion 204, but not limited thereto. In some embodiments, the optical layer 300, the adhesive layer 400, and / or the cover layer 120 can be selectively covered or not covered on the end portion 204, for example, but not limited thereto. It should be noted that the present invention is not limited to the structural design of the above embodiments. In some embodiments, the support structure 110 can selectively have a plurality of hole structures (not shown), and the hole structures can be correspondingly located within the rollable region R2, for example, to facilitate the bending of the support structure 110, but not limited thereto.

[0032] Please refer to Figure 4 , and in conjunction with Figure 1 , Figure 2 and Figure 3 , wherein Figure 4 is a partial enlarged cross-sectional schematic view of the rollable display device according to the first embodiment of the present invention, which shows the detailed corresponding relationship of each film layer of the rollable display device of the present invention. Figure 4 The rollable display device 100a shown can be applied to, for example, Figures 1 to 3 the rollable display device 100. As Figure 4As shown, in some embodiments, the rollable display device 100a may include a support structure 110, a display layer 200, an adhesive layer 400, an optical layer 300, and / or a cover layer 120 stacked in sequence along a first direction D1 (e.g., the normal direction of the substrate 230), but not limited thereto. In some embodiments, the support structure 110 may include a single-layer or multi-layer structure. In some embodiments, the support structure 110 may include at least one support plate 112 and at least one adhesive layer 114 (e.g., supporting structure glue), and the support plate 112 may be attached to the display layer 200 (e.g., the back side S2 of the display layer 200) through the adhesive layer 114, for example. In some embodiments, the thickness of the adhesive layer 114 may be, for example, 20 micrometers (um) to 300 micrometers (20 micrometers ≤ thickness ≤ 300 micrometers) or 30 micrometers to 200 micrometers (30 micrometers ≤ thickness ≤ 200 micrometers), such as 20 micrometers, 30 micrometers, 40 micrometers, 80 micrometers, but not limited thereto. In some embodiments, the material of the support plate 112 may include a metal material (e.g., but not limited to stainless steel material), a heat dissipation material, or other suitable materials, but not limited thereto. In some embodiments, the support plate 112 may be used as a heat sink, for example, but not limited thereto. As described above, the support plate 112 corresponding to the part of the rollable region R2 may have holes (or have a patterned design), so that the support plate 112 of this part has higher flexibility. In some embodiments, the display layer 200 may include a substrate 210, an adhesive layer 220, a substrate 230 (e.g., a flexible substrate), an insulating layer 240 (e.g., a buffer layer), a circuit layer 250, a light-emitting structure 260, a packaging layer 270, and / or a touch layer 280 stacked in sequence along the first direction D1, but not limited thereto. Other layers may be selectively inserted between any two stacked layers of the above display layer 200, or any stacked layer of the above display layer 200 may be selectively deleted. In some embodiments, the substrate 210 may include polyimide (PI), polyethylene terephthalate (PET), other suitable materials, or a combination of the above, but not limited thereto. In some embodiments, the substrate 230 may include polyimide or other suitable materials, for example. In some embodiments, the substrate 210 may be attached to the substrate 230 through the adhesive layer 220, and the thickness of the adhesive layer 220 may be, for example, 20 micrometers to 300 micrometers (20 micrometers ≤ thickness ≤ 300 micrometers) or 40 micrometers to 200 micrometers (40 micrometers ≤ thickness ≤ 200 micrometers), such as 20 micrometers, 30 micrometers, 40 micrometers, 80 micrometers, but not limited thereto.

[0033] In some embodiments, the circuit layer 250 may include a plurality of thin film transistors (TFTs) 252 and / or wires. The thin film transistors 252 may be used, for example, as switching elements, driving elements, but are not limited thereto. In Figure 4 this case, the thin film transistor 252 may include a channel layer 252C, a gate 252G, a source 252S, a drain 252D, and a gate insulating layer 252I, but is not limited thereto. Figure 4 The illustrated stacking of the thin film transistor 252 is only one example, but is not limited thereto. In some embodiments, the light-emitting structure 260 may include a plurality of light-emitting elements 262. The light-emitting elements 262 may include, for example, organic light-emitting diode elements or light-emitting diode elements. For example, the light-emitting element 262 may include a lower electrode 262a, a light-emitting layer 262b (such as an organic light-emitting layer), and an upper electrode 262c. The lower electrode 262a may be electrically connected to the drain 252D (or source 252S) of the thin film transistor 252, but is not limited thereto. In some embodiments, an insulating layer 264 may be selectively disposed on the upper surface of the light-emitting element 262. The insulating layer 264 may include an organic insulating layer, an inorganic insulating layer, or a combination thereof. In some embodiments, a light conversion layer (not shown) may be selectively disposed on different light-emitting elements 262. The light conversion layer may include a light filter, fluorescence, phosphorescence, or quantum dots, but is not limited thereto.

[0034] In some embodiments, the encapsulation layer 270 may cover the light-emitting structure 260. In some embodiments, the encapsulation layer 270 may serve as a planar layer or a protective layer. The encapsulation layer 270 may, for example, protect or reduce the chance of water and oxygen intrusion into the light-emitting structure 260 and the circuit layer 250. In some embodiments, the touch layer 280 may be disposed on the encapsulation layer 270, and the light-emitting structure 260 may be located between the touch layer 280 and the circuit layer 250, but is not limited thereto. In some embodiments, the touch layer 280 may include a composite layer. The touch layer 280 may include, for example, at least one insulating layer 290 and a plurality of touch elements 282 and / or wires (not shown). The touch elements 282 may include transmission electrodes and / or output electrodes, but are not limited thereto. The touch elements 282 may selectively have a grid structure (such as a metal mesh) or other structures. In some embodiments, in the first direction D1, the pattern of the touch layer 280 does not overlap with the light-emitting structure 260, for example. In some embodiments, the insulating layer 290 may cover the touch elements 282 to reduce the chance of water and oxygen intrusion into the touch elements 282. In some embodiments, the optical layer 300 may include a base layer 310 and a functional layer 320 disposed between the base layer 310 and the adhesive layer 400. In some embodiments, the functional layer 320 may contact the adhesive layer 400. For the materials of the base layer 310 and the functional layer 320, reference may be made to the following Figure 6 detailed description.

[0035] In some embodiments, an adhesive layer 122 (such as an optically clear adhesive (OCA)) may be selectively provided between the optical layer 300 and the cover layer 120 to bond the optical layer 300 and the cover layer 120 to each other. Through the above structural design, a rollable display device 100a with an on-cell touch function as shown in Figure 4 can be formed, but it is not limited thereto. It should be noted that the materials and thicknesses of the above-mentioned film layers are only examples. The materials of the film layers in the rollable display device 100a of the present invention may include other suitable materials not listed and the appropriate thickness can be adjusted according to the materials and design. The same applies to the following embodiments and will not be elaborated further.

[0036] Please refer to Figure 5 , and in conjunction with Figure 1 , Figure 2 and Figure 3 , where Figure 5 is a partial enlarged cross-sectional schematic diagram of the rollable display device according to the second embodiment of the present invention, which shows the detailed corresponding relationship of the film layers of the rollable display device of the present invention. Figure 5 The rollable display device 100b shown in Figures 1 to 3 can be applied to the rollable display device 100 in Figure 5 . As shown in Figure 5The touch layer 280 of the illustrated embodiment may be located, for example, between the circuit layer 250 and the light-emitting structure 260. The light-emitting element 262 (such as an inorganic light-emitting diode) in the light-emitting structure 260 may include, for example, a first electrode (not labeled), a first semiconductor layer (not labeled), a light-emitting layer 262d (such as an inorganic light-emitting layer), a second semiconductor layer (not labeled), and a second electrode (not labeled) stacked in sequence from bottom to top along the first direction D1. The first electrode may contact or be electrically connected to the lower electrode 262a, and the second electrode may contact or be electrically connected to the upper electrode 262c, but is not limited thereto. In some embodiments, the adhesive layer 122 between the optical layer 300 and the cover layer 120 may be selectively removed. In some embodiments, in the first direction D1, the pattern of a part of the touch layer 280 overlaps, for example, with the driving element 252, but is not limited thereto. In some embodiments, in the first direction D1, the pattern of a part of the touch layer 280 overlaps, for example, with a part of the lower electrode 262a, but is not limited thereto. The film layers, elements, structures, materials, etc. included in the rollable display device 100b in this embodiment may refer to the rollable display device 100a in the foregoing embodiment, and will not be elaborated herein. Through the above structural design, it can form a rollable display device 100b with in-cell touch as shown in Figure 5 shown.

[0037] Please refer to Figure 6 , Figure 6 which is a cross-sectional schematic view of the optical layer of the rollable display device according to an embodiment of the present invention. As shown in Figure 6 , the optical layer 300 may include a base layer 310 and a functional layer 320, and in the rollable display device 100 (or rollable display device 100a, rollable display device 100b), the optical layer 300 may be attached to the display layer 200 through, for example, an adhesive layer 400 (as shown in Figure 2 and Figure 3As shown, the functional layer 320 can be disposed between the base layer 310 and the adhesive layer 400, and the functional layer 320 can be attached to the base layer 310 through the adhesive layer 400. In some embodiments, the base layer 310 can include a flexible substrate material and can be used to carry the functional layer 320. In some embodiments, the material of the base layer 310 can, for example, include poly(methyl methacrylate) (PMMA), polyethylene terephthalate, tri-acetylcellulose (TAC), cycle-olefin polymer (COP), poly-vinylalcohol (PVA), or other suitable substrate materials or combinations thereof, but is not limited thereto. In some embodiments, the functional layer 320 can, for example, include an anti-reflection layer, a polarizing layer, a retardation layer, a light filtering layer, a light path adjustment layer, other suitable optical laminate structures, or combinations thereof, but is not limited thereto.

[0038] For example, the functional layer 320 can include a polarizing layer 322 and / or a retardation layer 324. The polarizing layer 322 can, for example, be disposed between the retardation layer 324 and the base layer 310, but is not limited thereto. In some embodiments, the polarizing layer 322 can include iodine, for example, include polyvinyl alcohol containing iodine, and its material can provide a polarization effect, but is not limited thereto. In some embodiments, the retardation layer 324 can include a liquid crystal material or other suitable materials to provide the function of phase retardation, but is not limited thereto. In some embodiments, the retardation layer 324 can be a quarter-wave retardation layer or a retardation layer of other suitable wavelengths (such as a half-wave retardation layer), but is not limited thereto. In some embodiments, the functional layer 320 can include at least one polarizing layer 322 and at least one retardation layer 324 (as Figure 6 shown). For example, the functional layer 320 can include a polarizing layer 322 and two retardation layers 324. The two retardation layers 324 can, for example, be a quarter-wave retardation layer and a half-wave retardation layer respectively. The half-wave retardation layer can, for example, be disposed between the quarter-wave retardation layer and the polarizing layer 322, but is not limited thereto. As Figure 6As shown, the optical layer 300 may include one or more intermediate layers 330, which may be selectively disposed between the polarization layer 322 and the base layer 310, between the retardation layer 324 and the polarization layer 322, and / or between the retardation layer 324 and the retardation layer 324. In some embodiments, the intermediate layer 330 may include, for example, an ultraviolet (UV) curable adhesive or other suitable adhesive layer, and the adhesion between layers can be enhanced through the intermediate layer 330, but not limited thereto. In some embodiments, the intermediate layer 330 may be selectively partially or completely removed to simplify the stack structure of the optical layer 300 and make the optical layer 300 thinner, but not limited to this.

[0039] In some embodiments, during the manufacturing process of the optical layer 300, the functional layer 320 may be formed on the base layer 310 through multiple coating processes. In some embodiments, the manufacturing process of the optical layer 300 may include the following steps. First, the base layer 310 is provided. Then, the polarization layer 322 is coated on the base layer 310. Alternatively, in some embodiments, the intermediate layer 330 may be coated on the base layer 310 first, and then the polarization layer 322 is coated on the intermediate layer 330, with the intermediate layer 330 serving as a connecting medium between the base layer 310 and the polarization layer 322, but not limited thereto. In some embodiments, the material of the polarization layer 322 may be coated on the base layer 310 by the blade coating method. The blade coating may, for example, align the polarization layer 322 simultaneously. After coating, it may be dried (for example, dried at a temperature of 80°C to 100°C, but not limited thereto). The polarization layer 322 is formed on the base layer 310 through the above method, but not limited thereto. In some embodiments, the alignment of the polarization layer 322 may be completed, for example, by photo-alignment, rubbing, photolithography, or other suitable alignment methods, but not limited thereto.

[0040] After the step of forming the polarization layer 322, the retardation layer 324 can be coated on the polarization layer 322, for example. Or, in some embodiments, the intermediate layer 330 can be coated on the polarization layer 322 first, and then the retardation layer 324 can be coated on the intermediate layer 330. The intermediate layer 330 serves as a connecting medium between the retardation layer 324 and the polarization layer 322. In some embodiments, the thickness of the intermediate layer 330 can be, for example, from 0.1 micrometer to 4 micrometers (0.1 micrometer ≤ thickness ≤ 4 micrometers) or from 0.2 micrometer to 3 micrometers (0.2 micrometer ≤ thickness ≤ 3 micrometers), but is not limited thereto. In some embodiments, the thickness of the retardation layer 324 can be, for example, from 1.5 micrometers to 4 micrometers (1.5 micrometers ≤ thickness ≤ 4 micrometers) or from 2 micrometers to 3.5 micrometers (2 micrometers ≤ thickness ≤ 3.5 micrometers), but is not limited thereto. In some embodiments, the retardation layer 324 can be a quarter-wave retardation layer, and it can be designed to correspond to a single wavelength (such as a wavelength of 550 nanometers (nm) or other suitable wavelengths), or designed to have multiple regions corresponding to different wavelengths of sub-pixels (such as corresponding to red, green, and blue wavelengths respectively), but is not limited thereto. In some embodiments, after the step of forming the retardation layer 324, another retardation layer 324 can be coated on the formed retardation layer 324, or in some embodiments, the intermediate layer 330 can be coated on the retardation layer 324 first, and then another retardation layer 324 can be coated on the intermediate layer 330, but is not limited thereto.

[0041] Please refer to Figure 7 , Figure 7 FIG. is a partial enlarged cross-sectional schematic view of the rollable display device according to the third embodiment of the present invention, which shows the detailed corresponding relationship of each film layer of the rollable display device of the present invention. Figure 7 The rollable display device 100c shown can be applied to Figures 1 to 3 in the rollable display device 100. As Figure 7 shown, in some embodiments, the rollable display device 100c can include a substrate SB, an insulating layer 240 (such as a buffer layer), a circuit layer 250, a light-emitting structure 260, a packaging layer 270, a touch layer 280, an adhesive layer 400, an optical layer 300, and / or a cover layer 120 stacked in sequence along the first direction D1. The manufacturing process of the rollable display device 100c can include the following steps. First, a substrate SB is provided. The substrate SB can include, for example, a substrate 210, an adhesive layer 220, and a substrate 230 as shown in Figure 4 or Figure 5 shown. Under the substrate SB, there can be provided, for example, a structure as shown in Figure 4 or Figure 5The support structure 110 shown, but not limited thereto. In some embodiments, the touch layer 280 may include multiple conductive layers. For example, the touch layer 280 may sequentially include a conductive layer 289, an insulating layer 290, a conductive layer 284, and / or an insulating layer 292. The conductive layer 284 may be filled into the opening of the insulating layer 290 to be electrically connected to the conductive layer 289. The insulating layer 292 may cover the conductive layer 284 and / or the conductive layer 289, but not limited thereto. In some embodiments, the conductive layer 289 and the conductive layer 284 may include a metal material or a transparent conductive material. For example, the conductive layer 289 and the conductive layer 284 may form a metal grid structure to form the touch electrodes of the touch layer 280, but not limited thereto. Figure 7 The rollable display device 100c shown is, for example, a multi-layer touch rollable display device 100c.

[0042] Please refer to Figure 8 , Figure 8 FIG. is a process schematic diagram of attaching an optical layer of a rollable display device according to an embodiment of the present invention to a display layer through an adhesive layer. As Figure 8 shown, the bonding process of the optical layer 300 and the display layer 200 may include the following steps. First, provide the optical layer 300. The optical layer 300 may include a base layer 310 and a functional layer 320. The functional layer 320 may include a polarization layer 322 and / or a retardation layer 324. The manufacturing process steps of the optical layer 300 may refer to the foregoing embodiments and will not be described herein again. Next, coat the adhesive layer 400 on the optical layer 300. For example, coat the adhesive layer 400 on the surface of the retardation layer 324 of the optical layer 300. Then, flip the structure of the optical layer 300 and the adhesive layer 400 so that the adhesive layer 400 faces the display layer 200, that is, the functional layer 320 is closer to the display layer 200 than the base layer 310. Next, apply pressure above the base layer 310 to attach the optical layer 300 to the display layer 200 through the adhesive layer 400. In some embodiments, the adhesive layer 400 may be first coated on the display layer 200, then the functional layer 320 of the optical layer 300 is faced to the adhesive layer 400, and then pressure is applied above the base layer 310 to attach the optical layer 300 to the display layer 200 through the adhesive layer 400. The lower side of the display layer 200 may have the substrate or the temporary carrier mentioned in the foregoing embodiments. In Figure 8Details are omitted. In summary, the processes of the layers (such as the polarization layer 322 and / or the retardation layer 324) in the optical layer 300 of the present invention can all be completed by coating processes. Compared with the conventional optical layer including multiple base layers, the optical layer 300 of the present invention can, for example, only include one base layer 310. This structural design can reduce the thickness of the optical layer 300, reduce the stress generated during the curling process of the rollable display device, and reduce the risk of damage to the display layer 200. In addition, during the bonding process of the optical layer 300 and the display layer 200, for example, applying pressure above the base layer 310 can reduce the chance of the functional layer 320 being scratched or damaged. In addition, the adhesive layer 400 in contact with the functional layer 320 can also protect the functional layer 320 from being scratched or damaged.

[0043] As Figure 8 shown on the right side of, after the optical layer 300 is attached to the display layer 200 through the adhesive layer 400 by applying pressure above the base layer 310, at least one edge 400e of the adhesive layer 400 protrudes more than the edge 320e of the corresponding functional layer 320 (or the edge 310e of the corresponding base layer 310). For example, the edge 400e of the adhesive layer 400 can be arc-shaped or other irregular shapes, so that the edge 400e of the adhesive layer 400 protrudes beyond the edge 320e of the corresponding functional layer 320 (or the edge 310e of the corresponding base layer 310), but is not limited thereto. By the degree of protrusion or the curvature of the edge 400e of the adhesive layer 400, it can be judged whether the bonding degree is within the standard range. For example, it can be judged whether the pressure applied to the base layer 310 is sufficient. For example, the adhesive layer 400 can have a thickness T, and the arc of the edge 400e of the adhesive layer 400 has a radius of curvature R. The radius of curvature R can be, for example, greater than or equal to 0.4 times the thickness T and less than or equal to 0.6 times the thickness T, that is, 0.4*T ≤ R ≤ 0.6*T, which can make it difficult for the optical layer 300 and the display layer 200 to peel off, but is not limited thereto. The measurement method of the thickness T of the adhesive layer 400 will be further described in the subsequent Figure 10 relevant content.

[0044] Please refer to Figure 9 , Figure 9 is a partially enlarged cross-sectional view of the display layer, the adhesive layer, and the optical layer of the rollable display device according to an embodiment of the present invention. The captured part shown is adjacent to the edge of the optical layer. The width WP of the captured part is, for example, 200 micrometers, that is, a partially enlarged cross-sectional view of the optical layer part from the edge 300e of the optical layer 300 inward to 200 micrometers. As Figure 9As shown, when performing the lamination process of the optical layer 300 and the display layer 200, at the edge of the optical layer 300 that is closer (such as the edge 310e of the base layer 310), the adhesive layer 400 is under relatively stronger pressure. That is, the pressure applied above the base layer 310, for example, increases as it approaches the edge 310e of the base layer 310. Therefore, the thickness Ta of the adhesive layer 400 corresponding to the edge 310e of the base layer 310 can be, for example, less than its thickness Tb away from the edge 310e of the base layer 310, that is, Ta < Tb. In this way, the edge of the optical layer 300 is less likely to be stretched and peeled off during the curling process. The thickness Ta can be defined as the thickness of the adhesive layer 400 on an extension line L_310e roughly taken from the edge 310e of the base layer 310. Additionally, the thickness Tb can be defined as the thickness of the adhesive layer 400 on an extension line L_1 taken approximately 200 micrometers away from the edge 310e of the base layer 310. In some embodiments, the ratio of the thickness Ta to the thickness Tb of the adhesive layer 400 is greater than or equal to 0.5 and less than 1, that is, 0.5 ≤ Ta / Tb < 1, but it is not limited thereto. This ensures that the thickness Ta of the adhesive layer 400 corresponding to the edge 310e of the base layer 310 is not too thin to cause insufficient adhesion, or the thickness Tb of the adhesive layer 400 is not too thick relative to the thickness Ta to be easily peeled off. The lower side of the display layer 200 of the present invention can have the substrate or the temporary carrier mentioned in the foregoing embodiments. In Figure 9 is omitted.

[0045] In some embodiments, the thicknesses of the layers of the optical layer 300 of the rollable display device of the present invention have a specific proportional relationship. Specifically, as Figure 8 shown, the thickness T1 of the base layer 310 is, for example, less than the thickness T of the adhesive layer 400, or the thickness T2 of the functional layer 320 is, for example, less than the thickness T1 of the base layer 310, that is, T1 < T or T2 < T1. The sum of the thickness T1 of the base layer 310 and the thickness T2 of the functional layer 320 is, for example, less than the thickness T of the adhesive layer 400, that is, (T2 + T1) < T. Among them, the range of the ratio of the thickness T2 of the functional layer 320 to the thickness T1 of the base layer 310 can be from 0.1 to 0.8, that is, 0.1 ≤ T2 / T1 ≤ 0.8, but it is not limited thereto. In some embodiments, the range of this ratio can be from 0.15 to 0.55, that is, 0.15 ≤ T2 / T1 ≤ 0.55. By designing the thicknesses of the layers of the optical layer 300 to have a specific proportional relationship as described above, the possibility of damage or functional failure due to stress inside the functional layer 320 during the lamination process of the optical layer 300 can be reduced, or the probability of peeling between the layers in the optical layer 300 due to stress can be decreased. Thereby, the functions and performances of the layers are improved, and the quality of the rollable display device is enhanced.

[0046] In addition, in the functional layer 320, the thickness T3 of the polarization layer 322 can be greater than the thickness T4 of the retardation layer 324, that is, T3 > T4. Since the polarization layer 322 and the retardation layer 324 are formed by, for example, a coating process, their thicknesses are generally consistent or uniform in each region, but this is not limited thereto. When the retardation layer 324 can include multiple sub-layers (not shown), an intermediate layer (not shown) can be selectively provided between these sub-layers. For example, when the retardation layer 324 includes a first sub-layer (e.g., a quarter-wave retardation layer) and a second sub-layer (e.g., a half-wave retardation layer), the thickness of the retardation layer 324 can be obtained by measuring the thicknesses of the respective sub-layers in the retardation layer 324 and summing up these thicknesses, that is, the thickness of the retardation layer 324 can ignore the thickness of the intermediate layer between the sub-layers in different retardation layers 324. When the polarization layer 322 can include multiple sub-layers (not shown), an intermediate layer (not shown) can be selectively provided between these sub-layers. Similarly, the thickness of the polarization layer 322 can be obtained by measuring the thicknesses of the respective sub-layers in the polarization layer 322 and summing up these thicknesses, that is, the thickness of the polarization layer 322 can ignore the thickness of the intermediate layer between the sub-layers in different polarization layers 322.

[0047] In some embodiments, the optical layer 300 and the display layer 200 of the rollable display device of the present invention have a specific proportional relationship. Specifically, as Figure 8 shown, the thickness of the optical layer 300 (substantially equal to the sum of the thickness T1 of the base layer 310 and the thickness T2 of the functional layer 320) is less than the thickness T5 of the display layer 200, that is, (T1 + T2) < T5. In some embodiments, the thickness range of the optical layer 300 can be from 10 μm to 50 μm (i.e., 10 μm ≤ the thickness of the optical layer 300 ≤ 50 μm) or from 20 μm to 40 μm (i.e., 20 μm ≤ the thickness of the optical layer 300 ≤ 40 μm). For example, the thickness of the optical layer 300 can be 20 μm, 30 μm, 45 μm, but this is not limited thereto. In some embodiments, the thickness range of the display layer 200, T5, can be from 45 μm to 300 μm (i.e., 45 μm ≤ thickness T5 ≤ 300 μm) or from 80 μm to 200 μm (i.e., 80 μm ≤ thickness T5 ≤ 200 μm). For example, the thickness T5 of the display layer 200 can be 60 μm, 75 μm, 110 μm, 150 μm, but this is not limited thereto. In some embodiments, the ratio of the thickness of the optical layer 300 (i.e., T1 + T2) to the thickness T5 of the display layer 200 can range from 0.3 to 0.6, that is, 0.3 ≤ (T1 + T2) / T5 ≤ 0.6. By the above design, the optical layer 300 and the display layer 200 have a specific proportional relationship, which can reduce the stress borne by the display layer 200 during repeated stretching and / or folding, and reduce the problems of damage or peeling between the circuits or laminations in the display layer 200. It should be noted that as Figure 4In the rollable display device 100a shown, the thickness T5 of the display layer 200 can be measured, for example, from the back side S2 of the display layer 200 (for example, the bottom surface of the substrate 210) to the front side S1 of the display layer 200 (for example, the surface of the insulating layer 290 away from the substrate 210). Figure 5 In the rollable display device 100b shown, the thickness T5 of the display layer 200 can be measured, for example, from the back side S2 of the display layer 200 (for example, the bottom surface of the substrate 210) to the front side S1 of the display layer 200 (for example, the surface of the encapsulation layer 270 away from the substrate 210). Figure 7 In the rollable display device 100c shown, the thickness T5 of the display layer 200 can be measured, for example, from the back side S2 of the display layer 200 (for example, the bottom surface of the substrate SB) to the front side S1 of the display layer 200 (for example, the surface of the insulating layer 292 of the touch layer 280 away from the substrate SB). It should be noted that the front side S1 of the display layer 200 can, for example, be in contact with the adhesive layer 400.

[0048] Please refer to Figure 10 , Figure 10 FIG. 1 is a schematic diagram of a partial cross section of a rollable display device according to an embodiment of the present invention. Figure 10 As shown, the rollable display device may include a display layer 200, an adhesive layer 400, an optical layer 300 and / or a covering layer 120, the display layer 200 may include a substrate 210, a glue layer 220 and / or a circuit layer 250, the optical layer 300 may include a base layer 310 and a functional layer 320 (which may be a composite layer), and the covering layer 120 may include a first covering layer 120a and / or a second covering layer 120b, but is not limited thereto. The aforementioned thickness T5 of the display layer 200, the thickness T of the adhesive layer 400, the thickness T2 of the functional layer 320, and the thickness T1 of the base layer 310 can be measured by taking a region at least 200 microns inward from the edge of the optical layer 300 (or, for example, the edge 310e of the base layer 310) in a cross-sectional view of the rollable display device (for example, an image of a scanning electron microscope can be used, but not limited thereto), and taking any vertical line VL that can pass through the layers at the same time in this region, the thickness of each layer can be defined as the thickness of each layer measured along this vertical line VL. In addition, if Figure 10 As shown, the thickness Ta of the adhesive layer 400 corresponding to the edge 310e of the base layer 310 is measured as described above. An extension line L_310e (not shown) can be roughly drawn from the edge 310e of the base layer 310. Figure 10 , the extension line L_310e can refer to Figure 9 ), the thickness of the adhesive layer 400 corresponding to the extension line L_310e is defined as thickness Ta, but is not limited thereto.

[0049] In summary, for the rollable display device according to the embodiments of the present invention, through the structural design of the optical layer and by attaching the optical layer to the display layer with the adhesive layer, the influence of the stress generated during repeated extension and / or folding on the film layers in the structure can be reduced, or the stress distribution in the structure can be adjusted in this way, reducing the risk of device damage, improving the functions and performances of the various layers in the rollable display device, so as to enhance the quality of the rollable display device and its display screen.

[0050] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the scope of the present invention.

Claims

1. A display device having a first display state and a second display state, characterized in that, The display device includes: A display layer, which has a larger display area when the display device is in the second display state than when it is in the first display state, wherein the display layer includes: A substrate; A light-emitting structure disposed on the substrate; An insulating layer disposed on the substrate; and A touch element disposed between the light-emitting structure and the insulating layer; A flexible material layer; and An adhesive layer attached between the insulating layer of the display layer and the flexible material layer, wherein in a cross-sectional view, an edge of the adhesive layer has an arc shape.

2. The display device according to claim 1, characterized in that, The light-emitting structure includes a plurality of light-emitting elements.

3. The display device according to claim 2, wherein The plurality of light-emitting elements include a plurality of inorganic light-emitting diodes.

4. The display device according to claim 2, wherein The plurality of light-emitting elements include a plurality of organic light-emitting diodes.

5. The display device according to claim 1, wherein The touch element has a grid structure.

6. The display device according to claim 5, wherein, The touch element has a metal grid structure.

7. The display device according to claim 1, wherein, It further includes a support plate, wherein the display layer is disposed between the support plate and the adhesive layer.

8. The display device according to claim 7, wherein The support plate includes a metal material.

9. The display device according to claim 8, wherein The support plate has holes.

10. The display device according to claim 1, wherein, The display layer further includes a circuit layer disposed between the substrate and the light-emitting structure.

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