Rollable display device

Abstract

The present invention discloses a rollable display device having a general display state and an extended display state. The rollable display device comprises a display layer and an optical layer. When the rollable display device is in the extended display state, the display layer has a larger display area than when in the general display state. The optical layer is attached to the display layer through an adhesive layer, and the optical layer comprises a base layer and a functional layer arranged between the base layer and the adhesive layer. The functional layer contacts the adhesive layer.

Description

Technical Field

[0001] The present invention relates to a rollable display device, in particular to a rollable display device with an optical layer. Background Art

[0002] In recent years, rollable display devices or deformable display devices have become one of the focuses of new generation electronic technology. Generally, the display area of ​​a rollable display device or deformable display device can be changed by rolling, but the stress generated by its structure during the extension and / or folding process will affect the display performance or cause damage to the display device. Therefore, manufacturers need to develop a suitable structural design to reduce the problem caused by stress. Summary of the invention

[0003] An embodiment of the present invention provides a rollable display device, the rollable display device has a normal display state and an extended display state, and the rollable display device includes a display layer and an optical layer. When the rollable display device is in the extended display state, the display layer has a larger display area than in the normal display state. The optical layer is attached to the display layer through an adhesive layer, and the optical layer includes a base layer and a functional layer disposed between the base layer and the adhesive layer, wherein the functional layer contacts the adhesive layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] Figure 1 Schematic diagram of a rollable display device in different states according to an embodiment of the present invention.

[0005] Figure 2 FIG. 4 is a cross-sectional schematic diagram of a rollable display device in a normal display state according to an embodiment of the present invention.

[0006] Figure 3 FIG. 4 is a cross-sectional schematic diagram of a rollable display device in an extended display state according to an embodiment of the present invention.

[0007] Figure 4 FIG. 1 is a partially enlarged cross-sectional schematic diagram of a rollable display device according to a first embodiment of the present invention.

[0008] Figure 5 FIG. 4 is a partially enlarged cross-sectional schematic diagram of a rollable display device according to a second embodiment of the present invention.

[0009] Figure 6 FIG. 4 is a cross-sectional schematic diagram of an optical layer of a rollable display device according to an embodiment of the present invention.

[0010] Figure 7 FIG. 4 is a partially enlarged cross-sectional schematic diagram of a rollable display device according to a third embodiment of the present invention.

[0011] Figure 8It is a schematic diagram of a process of attaching an optical layer of a rollable display device to a display layer via an adhesive layer according to an embodiment of the present invention.

[0012] Fig. 9 It is a partial cross-sectional enlarged schematic diagram of a display layer, an adhesive layer and an optical layer of a rollable display device according to an embodiment of the present invention.

[0013] Fig.10 FIG. 4 is a schematic diagram illustrating a partial cross section of a rollable display device according to an embodiment of the present invention.

[0014] Description of reference numerals: 100, 100a, 100b, 100c-rollable display device; 102-rotating element; 110-support structure; 112-support plate; 114, 122, 220-glue layer; 120-covering layer; 120a-first covering layer; 120b-second covering 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; 2 62c-upper electrode; 270-packaging 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-delay layer; 330-intermediate layer; 400-adhesive layer; D1-first direction; D-distance; X-extension direction; DR-display area; I-normal display state; II-extension display state; R-radius of curvature; R1-non-curling area; R2-curling 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

[0015] The present invention can be understood by referring to the following detailed description in conjunction with the accompanying drawings. It should be noted that in order to facilitate the reader's understanding and simplify the drawings, the multiple drawings in the present invention only depict a portion of the electronic device, and the specific components in the drawings are not drawn according to the actual scale. In addition, the number and size of each component in the drawings are only for illustration and are not intended to limit the scope of the present invention.

[0016] Certain words are used throughout the specification and claims of the present invention to refer to specific components. It should be understood by those skilled in the art that electronic equipment manufacturers may refer to the same components by different names. It is not intended to distinguish between components that have the same function but different names. In the following specification and claims, the words "include", "contain", "have" and the like are open-ended words, and therefore should be interpreted as "including but not limited to...". Therefore, when the terms "include", "contain" and / or "have" are used in the description of the present invention, they specify the existence of corresponding features, regions, steps, operations and / or components, but do not exclude the existence of one or more corresponding features, regions, steps, operations and / or components.

[0017] The directional terms mentioned herein, such as "up", "down", "front", "back", "left", "right", etc., are only references to the directions of the accompanying drawings. Therefore, the directional terms used are for illustration and not for limiting the present invention. In the accompanying drawings, each diagram depicts the general characteristics of the methods, structures and / or materials used in a particular embodiment. However, these diagrams should not be interpreted as defining or limiting the scope or nature covered by these embodiments. For example, for clarity, the relative size, thickness and position of each film layer, region and / or structure may be reduced or enlarged.

[0018] When a corresponding component (such as a film layer or region) is referred to as being "on another component", it may be directly on the other component, or other components may exist between the two. On the other hand, when a component is referred to as being "directly on another component", there is no component between the two. In addition, when a component is referred to as being "on another component", the two have a top-down relationship in a top-down direction, and the component may be above or below the other component, and the top-down relationship depends on the orientation of the device.

[0019] The terms "approximately," "equal," "equal," or "same," "substantially," or "approximately" are generally interpreted as within 20% of a given value or range, or within 10%, 5%, 3%, 2%, 1% or 0.5% of a given value or range.

[0020] The ordinal numbers used in the specification and claims, such as "first", "second", etc., are used to modify the elements. They do not imply or represent any previous ordinal numbers of the (or the multiple) elements, nor do they represent the order of one element and another element or the order of the manufacturing method. The use of multiple ordinal numbers is only used to make the element with a certain name clearly distinguishable from another element with the same name. The claims and the specification may not use the same words. Accordingly, the first component in the specification may be the second component in the claims.

[0021] It should be noted that the following embodiments can replace, reorganize, or mix features in several different embodiments to complete other embodiments without departing from the spirit of the present invention. The features between the embodiments can be mixed and matched as long as they do not violate the spirit of the invention or conflict with each other.

[0022] In the present invention, the thickness, length and width can be measured by an optical microscope, and the thickness can be measured by a cross-sectional image in an electron microscope, but it is not limited to this. In addition, any two values ​​or directions used for comparison may have a certain error. 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 may 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 may be between 0 degrees and 10 degrees.

[0023] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meanings as commonly understood by those skilled in the art to which the present invention belongs. It is understood that these terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the background or context of the relevant technology and 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.

[0024] Please refer to Figure 1 , Figure 2 and Figure 3 . Figure 1 Schematic diagram of a rollable display device in different states according to an embodiment of the present invention. Figure 2 FIG. 4 is a cross-sectional schematic diagram of a rollable display device in a normal display state according to an embodiment of the present invention. Figure 3 FIG. 1 is a cross-sectional schematic diagram of a rollable display device in an extended display state according to an embodiment of the present invention. 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 may be attached to the display layer 200 through an adhesive layer 400. The display layer 200 may include a display medium, such as liquid crystal, light emitting diode (LED), quantum dot (QD), fluorescence or phosphor. The light emitting diode may include, for example, an organic light emitting diode (OLED), a millimeter / sub-millimeter light emitting diode (mini LED), a micro LED or a quantum dot light emitting diode (quantum dot LED, which may be, for example, QDLED), but is not limited thereto.

[0025] In some embodiments, the display layer 200 has a display area DR, which is an area for displaying a picture when the rollable display device 100 is in motion. The area of ​​the display area DR can be changed by folding or unfolding the partially rollable display layer 200. For example, the rollable display device 100 may have a non-rolling area R1 and a rollable area R2, and the rollable area R2 is, for example, connected to one side of the non-rolling area R1. The area of ​​the non-rolling area R1 as viewed from the top is fixed, and the rollable area R2 can be, for example, by rotating the element 102 (such as a rotating shaft or a roller) or other suitable elements to fold or unfold the rollable area R2, but is not limited thereto. In some embodiments, the area of ​​the display area DR can be changed, for example, according to the folding or unfolding of the rollable area R2. In some embodiments, the state of the rollable region R2 of the rollable display device 100 when fully folded is defined as a general display state I, and the state of the rollable region R2 of the rollable display device 100 when at least partially unfolded is defined as an extended display state II, that is, the extended display state II includes a state in which the rollable region R2 is partially unfolded (e.g. Figure 3 The rollable region R2 is mostly unfolded (as shown in the upper part) Figure 3 When the rollable display device 100 is in the extended display state II, the display layer 200 may have a larger display area DR than in the normal display state I, for example.

[0026] It should be noted that although the non-curling region R1 is shown as a flat shape in the drawings, in other embodiments (not shown), the non-curling region R1 may be wavy or have curved edges, but the area of ​​the non-curling region R1 in the top view direction remains fixed.

[0027] It should be noted that the rollable display device 100 may optionally include a frame (not shown) or a shielding element (not shown), and the frame or the shielding element may selectively overlap or cover the rotating element 102 and / or a portion of the display layer 200. Figure 1 The change of the display area DR of the illustrated rollable display device 100 in the normal display state I and the extended display state II may vary depending on the condition of the display layer 200 being shielded by the above-mentioned frame or the above-mentioned 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 normal display state I.

[0028] like Figure 2 and Figure 3 As 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 (e.g., 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 is not limited thereto. In some embodiments (not shown), the display layer 200 and the support structure 110 may be bonded together by a glue layer (not shown). In some embodiments, the optical layer 300 may be attached to the front side S1 of the display layer 200 by 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-curing glue, optically clear adhesive (OCA), optically clear resin (OCR), heat-curing glue, moisture-curing glue, pressure sensitive adhesive (PSA) or other suitable glue or any combination thereof, but is not limited thereto. In some embodiments, the material of the adhesive layer 400 may include acrylate or other suitable materials, but is 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.

[0029] In some embodiments, the display layer 200 may have an end 202 and an end 204 located on opposite sides. In some embodiments, the end 202 may be, for example, connected to a portion of the display layer 200 located in the non-curling region R1 and fixed. In some embodiments, the end 202 may be, for example, bent 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, for example, fixed to the support structure 110 by 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 may be, for example, located in the rollable region R2. In some embodiments, the end 204 may be moved, for example, by rotating the element 102 or other suitable elements, so that the rollable region R2 is folded or unfolded. In some embodiments, the end 204 may be moved to different positions (such as Figure 3 Upper and Figure 3 In some embodiments, the end 204 can be moved, for example, by rotating the element 102 or other suitable elements to change the distance D between the end 204 and the end 202. The distance D can be defined as the minimum distance between the end 204 and the end 202 in the extension direction X. In some embodiments, regardless of the normal display state I or the extended display state II, the end 202 and / or the end 204 can be, for example, located on the side of the support structure 110 away from the display surface DS. In some embodiments, when the display area DR in the rollable area R2 is fully unfolded (e.g., Figure 3 As shown in the lower part, the end 204 of the display layer 200 can still be disposed under the support structure 110 so that part of the display layer 200 can be in a rolled-up state. This design can make it easier to fold the fully unfolded rollable area R2 again.

[0030] In some embodiments, the signal pad 130 may be disposed on the end portion 202, the display layer 200 may be connected to the circuit board 140 through the signal pad 130, and the circuit board 140 may transmit a signal to control the driving of the display layer 200, but the present invention is not limited thereto. Figure 2As shown, since the signal pad 130 is disposed on the end 202, the signal pad 130 can be more stably electrically connected to the circuit board 140, but not limited thereto. In some embodiments, the circuit board 140 can be, for example, disposed under the support structure 110 and can be selectively fixed to the support structure 110. In some embodiments, since the signal pad 130 is disposed on the end 202 of the display layer 200 but not used to display the picture, the optical layer 300, the adhesive layer 400 and / or the covering layer 120 can be selectively not disposed or covered on the end 202, but not limited thereto. In some embodiments, an integrated circuit chip or a control unit can be selectively disposed 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, for example, connected to the signal pad 130, but not limited thereto. In some embodiments, since the end 204 of the display layer 200 can be non-used to display the picture, the optical layer 300, the adhesive layer 400 and / or the covering layer 120 can be selectively not disposed on the end 204, but not limited thereto. In some embodiments, the optical layer 300, the adhesive layer 400 and / or the cover layer 120 may selectively cover or not cover the end portion 204, but the invention is not limited thereto. It should be noted that the invention is not limited to the structural design of the above-mentioned embodiments. In some embodiments, the support structure 110 may selectively have a plurality of hole structures (not shown), and the hole structures may be correspondingly located in the rollable region R2, for example, to facilitate the bending of the support structure 110, but the invention is not limited thereto.

[0031] Please refer to Figure 4 , and cooperate with Figure 1 , Figure 2 and Figure 3 ,in Figure 4 FIG. 1 is a partially enlarged cross-sectional schematic diagram of a rollable display device according to a first embodiment of the present invention, which illustrates the detailed correspondence between the film layers of the rollable display device according to the present invention. Figure 4 The rollable display device 100a shown can be applied to Figures 1 to 3 In the rollable display device 100. 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., a normal direction of the substrate 230), but is 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 glue layer 114 (e.g., a 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 glue layer 114. In some embodiments, the thickness of the glue layer 114 may be, for example, 20 microns (um) to 300 microns (20 microns ≤ thickness ≤ 300 microns) or 30 microns to 200 microns (30 microns ≤ thickness ≤ 200 microns), for example, 20 microns, 30 microns, 40 microns, 80 microns, but is not limited thereto. In some embodiments, the material of the support plate 112 may include a metal material (for example, but not limited to a stainless steel material), a heat dissipation material or other suitable material, but is not limited thereto. In some embodiments, the support plate 112 may be used, for example, as a heat sink, but is not limited thereto. As described above, the support plate 112 corresponding to the portion of the rollable region R2 may, for example, have holes (or have a patterned design) so that the support plate 112 of that portion has higher flexibility. In some embodiments, the display layer 200 may, for example, include a substrate 210, a glue layer 220, a substrate 230 (for example, a flexible substrate), an insulating layer 240 (for example, a buffer layer), a circuit layer 250, a light-emitting structure 260, an encapsulation layer 270 and / or a touch layer 280 stacked in sequence along a first direction D1, but is not limited thereto. Other layers may be selectively inserted between any two stacks in the above-mentioned display layer 200, or any stack in the above-mentioned display layer 200 may be selectively deleted. In some embodiments, the substrate 210 may include polyimide (PI), polyethylene terephthalate (PET), other suitable materials or combinations thereof, but is not limited thereto. In some embodiments, the substrate 230 may include, for example, polyimide or other suitable materials. In some embodiments, the substrate 210 may be attached to the substrate 230 via the adhesive layer 220, and the thickness of the adhesive layer 220 may be, for example, 20 microns to 300 microns (20 microns ≤ thickness ≤ 300 microns) or 40 microns to 200 microns (40 microns ≤ thickness ≤ 200 microns), for example, 20 microns, 30 microns, 40 microns, 80 microns, but is not limited thereto.

[0032] In some embodiments, the circuit layer 250 may include a plurality of thin film transistors (TFTs) 252 and / or conductive lines. The thin film transistors 252 may be used as switch elements or drive elements, but are not limited thereto. Figure 4 In the embodiment, 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 stacking of the thin film transistor 252 shown is only one example, but not limited to this. In some embodiments, the light emitting structure 260 may include a plurality of light emitting elements 262, and the light emitting element 262 may include, for example, an organic light emitting diode element or a light emitting diode element. 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, and the lower electrode 262a may be, for example, electrically connected to the drain 252D (or source 252S) of the thin film transistor 252, but not limited to this. In some embodiments, the upper surface of the light emitting element 262 may be selectively provided with an insulating layer 264, and the insulating layer 264 may include an organic insulating layer, an inorganic insulating layer, or a combination thereof. In some embodiments, light conversion layers (not shown) may be selectively provided on different light emitting elements 262, and the light conversion layers may include filter materials, fluorescence, phosphorescence, or quantum dots, but not limited to this.

[0033] In some embodiments, the encapsulation layer 270 may cover the light emitting structure 260. In some embodiments, the encapsulation layer 270 may be used as a flat layer or a protective layer. For example, the encapsulation layer 270 may 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. For example, the touch layer 280 may include at least one insulating layer 290 and a plurality of touch elements 282 and / or wires (not shown). The touch element 282 may include a transmission electrode and / or an output electrode, but is not limited thereto. The touch element 282 may selectively have a mesh structure (for example, a metal mesh) or other structures. In some embodiments, in the first direction D1, the pattern of the touch layer 280, for example, does not overlap with the light emitting structure 260. In some embodiments, the insulating layer 290 may cover the touch element 282 to reduce the chance of water and oxygen intrusion into the touch element 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 materials of the base layer 310 and the functional layer 320, please refer to the following Figure 6 Detailed description.

[0034] In some embodiments, an adhesive layer 122 (such as optically clear adhesive (OCA)) may be selectively provided between the optical layer 300 and the cover layer 120 to adhere the optical layer 300 and the cover layer 120 to each other. Figure 4 The rollable display device 100a of the touch-sensitive type (on-cell touch) is shown, but is not limited thereto. It should be noted that the materials and thicknesses of the above-mentioned film layers are only examples, and 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 may be adjusted according to the material and design, and the following embodiments are also the same and will not be repeated.

[0035] Please refer to Figure 5 , and cooperate with Figure 1 , Figure 2 and Figure 3 ,in Figure 5 FIG. 2 is a partially enlarged cross-sectional schematic diagram of a rollable display device according to a second embodiment of the present invention, which illustrates the detailed correspondence between the film layers of the rollable display device according to the present invention. Figure 5 The rollable display device 100b shown can be applied to Figures 1 to 3 In the rollable display device 100. Figure 5 As shown, the rollable display device 100b may include a support structure 110, a display layer 200, an adhesive layer 400, an optical layer 300, a glue layer 122 and / or a cover layer 120 stacked in sequence along a first direction D1. The support structure 110 may include at least one support plate 112 and at least one glue layer 114. In some embodiments, the display layer 200 may include a substrate 210, a glue layer 220, a substrate 230, an insulating layer 240, a circuit layer 250, a touch layer 280, a light-emitting structure 260 and / or an encapsulation layer 270 stacked in sequence along the first direction D1, but is not limited thereto. Similarly, the optical layer 300 may include a base layer 310 and a functional layer 320, and the functional layer 320 is disposed between the base layer 310 and the adhesive layer 400. Different from the previous embodiment, Figure 5The touch layer 280 of the embodiment shown may be, for example, located between the circuit layer 250 and the light emitting structure 260. The light emitting element 262 (e.g., an inorganic light emitting diode) in the light emitting structure 260 may include, for example, a first electrode (not shown), a first semiconductor layer (not shown), a light emitting layer 262d (e.g., an inorganic light emitting layer), a second semiconductor layer (not shown), and a second electrode (not shown) stacked in order from bottom to top along the first direction D1. The first electrode may, for example, contact or be electrically connected to the lower electrode 262a, and the second electrode may, for example, contact or be electrically connected to the upper electrode 262c, but is not limited thereto. In some embodiments, the glue layer 122 between the optical layer 300 and the cover layer 120 may be selectively removed. In some embodiments, in the first direction D1, a portion of the pattern of the touch layer 280 may, for example, overlap with the driving element 252, but is not limited thereto. In some embodiments, in the first direction D1, a portion of the pattern of the touch layer 280 may, for example, overlap with a portion of the lower electrode 262a, but is not limited thereto. The film layers, components, structures and materials included in the rollable display device 100b of this embodiment can refer to the rollable display device 100a of the aforementioned embodiment, and will not be described in detail here. Figure 5 The rollable display device 100b is an in-cell touch display.

[0036] Please refer to Figure 6 , Figure 6 FIG. 1 is a cross-sectional schematic diagram of an optical layer of a rollable display device according to an embodiment of the present invention. Figure 6 As shown, the optical layer 300 may include a base layer 310 and a functional layer 320, and in the rollable display device 100 (or the rollable display device 100a, the rollable display device 100b), the optical layer 300 may be attached to the display layer 200 (such as the rollable display device 100a) by, for example, an adhesive layer 400. Figure 2 and Figure 3As shown in the figure, the functional layer 320 may be disposed between the base layer 310 and the adhesive layer 400, and the functional layer 320 may be attached to the base layer 310 through the adhesive layer 400. In some embodiments, the base layer 310 may include a soft substrate material, which may be used to carry the functional layer 320. In some embodiments, the material of the base layer 310 may include, for example, poly(methyl methacrylate) (PMMA), polyethylene terephthalate, triacetylcellulose (TAC), cycle-olefin polymer (COP), polyvinyl alcohol (PVA) or other suitable substrate materials or combinations thereof, but is not limited thereto. In some embodiments, the functional layer 320 may include, for example, an anti-reflection layer, a polarizing layer, a retardation layer, a filter layer, a light path adjustment layer, other suitable optical stacking structures or combinations thereof, but is not limited thereto.

[0037] For example, the functional layer 320 may include a polarizing layer 322 and / or a delay layer 324. The polarizing layer 322 may be, for example, disposed between the delay layer 324 and the base layer 310, but is not limited thereto. In some embodiments, the polarizing layer 322 may include iodine, such as polyvinyl alcohol containing iodine, and the material may provide a polarization effect, but is not limited thereto. In some embodiments, the delay layer 324 may include a liquid crystal material or other suitable material to provide a phase delay function, but is not limited thereto. In some embodiments, the delay layer 324 may be a quarter-wave delay layer or a delay layer of other suitable wavelength (such as a half-wave delay layer), but is not limited thereto. In some embodiments, the functional layer 320 may include at least one polarizing layer 322 and at least one delay layer 324 (such as Figure 6 For example, the functional layer 320 may include a polarizing layer 322 and two retardation layers 324. The two retardation layers 324 may be, for example, a quarter-wavelength retardation layer and a half-wavelength retardation layer, respectively. The half-wavelength retardation layer may be, for example, disposed between the quarter-wavelength retardation layer and the polarizing layer 322, but is not limited thereto. Figure 6As shown, the optical layer 300 may include one or more intermediate layers 330, and the intermediate layers 330 may be selectively disposed between the polarizing layer 322 and the base layer 310, between the retardation layer 324 and the polarizing 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, ultraviolet curing glue (UV glue) or other suitable glue layers, and the adhesion between the layers may be improved by the intermediate layer 330, but the invention is not limited thereto. In some embodiments, the intermediate layer 330 may be partially or completely removed to simplify the stacking structure of the optical layer 300 and make the thickness of the optical layer 300 thinner, but the invention is not limited thereto.

[0038] In some embodiments, in the process of manufacturing the optical layer 300, the functional layer 320 may be formed on the base layer 310 through a multi-pass coating process. In some embodiments, the process of manufacturing the optical layer 300 may include the following steps. First, a base layer 310 is provided. Next, the polarizing layer 322 is coated on the base layer 310, or, in some embodiments, the intermediate layer 330 may be coated on the base layer 310 first, and then the polarizing layer 322 is coated on the intermediate layer 330, and the intermediate layer 330 is used as a connecting medium between the base layer 310 and the polarizing layer 322, but not limited thereto. In some embodiments, the material of the polarizing layer 322 may be coated on the base layer 310 by a blade coating method, and the blade coating may, for example, align the polarizing layer 322 at the same time, and after the coating is completed, it may be dried (for example, dried at a temperature of 80° C. to 100° C., but not limited thereto), and the polarizing layer 322 may be formed on the base layer 310 by the above method, but not limited thereto. In some embodiments, the alignment of the polarizing layer 322 may be achieved, for example, by photo-alignment, rubbing, photolithography or other suitable alignment methods, but is not limited thereto.

[0039] After the step of forming the polarizing layer 322, the retardation layer 324 may be coated on the polarizing layer 322, or, in some embodiments, the intermediate layer 330 may be coated on the polarizing layer 322 first, and then the retardation layer 324 may be coated on the intermediate layer 330, and the intermediate layer 330 may be used as a connecting medium between the retardation layer 324 and the polarizing layer 322. In some embodiments, the thickness of the intermediate layer 330 may be, for example, 0.1 micrometer to 4 micrometers (0.1 micrometer ≤ thickness ≤ 4 micrometers) or 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 may be, for example, 1.5 micrometers to 4 micrometers (1.5 micrometers ≤ thickness ≤ 4 micrometers) or 2 micrometers to 3.5 micrometers (2 micrometers ≤ thickness ≤ 3.5 micrometers), but is not limited thereto. In some embodiments, the delay layer 324 may be a quarter-wavelength delay layer, and it may be designed to correspond to a single wavelength (e.g., a wavelength of 550 nanometers (nm) or other suitable wavelengths), or to have multiple regions corresponding to different wavelengths of sub-pixels (e.g., corresponding to red light, green light, and blue light wavelengths, respectively), but not limited thereto. In some embodiments, after the step of forming the delay layer 324, another delay layer 324 may be coated on the formed delay layer 324, or in some embodiments, the intermediate layer 330 may be coated on the delay layer 324 first, and then another delay layer 324 may be coated on the intermediate layer 330, but not limited thereto.

[0040] Please refer to Figure 7 , Figure 7 FIG. 1 is a partially enlarged cross-sectional schematic diagram of a rollable display device according to a third embodiment of the present invention, which illustrates the detailed correspondence between the film layers of the rollable display device according to 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. Figure 7 As shown, in some embodiments, the rollable display device 100c may include a substrate SB, an insulating layer 240 (e.g., a buffer layer), a circuit layer 250, a light emitting structure 260, an encapsulation layer 270, a touch layer 280, an adhesive layer 400, an optical layer 300 and / or a cover layer 120 stacked in sequence along a first direction D1. The manufacturing process of the rollable display device 100c may include the following steps. First, a substrate SB is provided. The substrate SB may include, for example, Figure 4 or Figure 5 The substrate 210, the adhesive layer 220 and the substrate 230 shown in the figure, the substrate SB may be provided with Figure 4 or Figure 5The support structure 110 shown in the figure is not limited thereto. In some embodiments, the touch layer 280 may include multiple conductive layers. The touch layer 280 may include, for example, a conductive layer 289, an insulating layer 290, a conductive layer 284 and / or an insulating layer 292 in sequence. The conductive layer 284 may, for example, be filled into the opening of the insulating layer 290 to be electrically connected to the conductive layer 289. The insulating layer 292 may, for example, cover the conductive layer 284 and / or the conductive layer 289, but is 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 a touch electrode of the touch layer 280, but is not limited thereto. Figure 7 The rollable display device 100 c shown is, for example, a multi-layer touch rollable display device 100 c .

[0041] Please refer to Figure 8 , Figure 8 This is a schematic diagram of a process 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. Figure 8 As shown, the bonding process of the optical layer 300 and the display layer 200 may include the following steps. First, an optical layer 300 is provided. The optical layer 300 may include a base layer 310 and a functional layer 320. The functional layer 320 may include a polarizing layer 322 and / or a delay layer 324. The process steps of the optical layer 300 may refer to the aforementioned embodiments and will not be repeated here. Next, an adhesive layer 400 is coated on the optical layer 300, for example, the adhesive layer 400 is coated on the surface of the delay layer 324 of the optical layer 300. Then, the structure of the optical layer 300 and the adhesive layer 400 is turned over so that the adhesive layer 400 faces the display layer 200, that is, the functional layer 320 is closer to the display layer 200 relative to the base layer 310. Next, pressure is applied on the base layer 310 so that the optical layer 300 is attached to the display layer 200 through the adhesive layer 400. In some embodiments, the adhesive layer 400 may be coated on the display layer 200 first, and then the functional layer 320 of the optical layer 300 may face the adhesive layer 400, and then pressure is applied on 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 temporary carrier mentioned in the above embodiments. Figure 8. In summary, the processes of the layers (such as the polarizing layer 322 and / or the delay layer 324) in the optical layer 300 of the present invention can all be completed by a coating process. Compared with the traditional optical layer including multiple substrate layers, the optical layer 300 of the present invention may, for example, only include one substrate layer 310. This structural design can reduce the thickness of the optical layer 300, thereby reducing the stress generated by the rollable display device during the roll-up process and reducing the risk of damage to the display layer 200. In addition, in the bonding process of the optical layer 300 and the display layer 200, for example, applying pressure on the substrate 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.

[0042] like Figure 8 As shown on the right side of the figure, by applying pressure on the base layer 310, the optical layer 300 is attached to the display layer 200 through the adhesive layer 400, and at least one edge 400e of the adhesive layer 400 is more prominent 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 may be curved or have other irregular shapes, so that the edge 400e of the adhesive layer 400 protrudes from the edge 320e of the corresponding functional layer 320 (or the edge 310e of the corresponding base layer 310), but is not limited thereto. The protrusion or curvature of the edge 400e of the adhesive layer 400 can be used to determine whether the degree of lamination is within the standard range, for example, whether the pressure applied to the base layer 310 is sufficient. For example, the adhesive layer 400 may have a thickness T, and the arc of the edge 400e of the adhesive layer 400 has a curvature radius R, and the curvature radius R may 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, so that the optical layer 300 and the display layer 200 are not easily peeled off, but the present invention is not limited thereto. The method for measuring the thickness T of the adhesive layer 400 will be described in detail later. Fig.10 The relevant content will be further explained.

[0043] Please refer to Fig. 9 , Fig. 9 FIG. 1 is a partial cross-sectional enlarged schematic diagram of a display layer, an adhesive layer and an optical layer of a rollable display device according to an embodiment of the present invention, wherein the captured portion shown is adjacent to the edge of the optical layer, and the width WP of the captured portion is, for example, 200 microns, i.e., a partial cross-sectional enlarged schematic diagram of the optical layer portion from the edge 300e of the optical layer 300 to 200 microns inward. Fig. 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 peeled off by stretching during the curling process. The thickness Ta can be defined as the thickness of the adhesive layer 400 on an extension line L_310e approximately 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 adhesiveness, or that 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 Fig. 9 is omitted.

[0044] 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, 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 reduced, thereby improving the functions and performances of the layers and enhancing the quality of the rollable display device.

[0045] In addition, in the functional layer 320, the thickness T3 of the polarization layer 322 may be greater than the thickness T4 of the retardation layer 324, i.e., T3>T4. Since the polarization layer 322 and the retardation layer 324 are, for example, both formed by a coating process, their thicknesses are generally uniform or consistent in each region, but this is not limited thereto. When the retardation layer 324 may include multiple sub-layers (not shown), an intermediate layer (not shown) may be selectively provided between these sub-layers, for example. For instance, 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 overall thickness of the retardation layer 324 may be obtained, for example, by separately measuring the thicknesses of the respective sub-layers in the retardation layer 324 and adding up these sub-layer thicknesses, i.e., the thickness of the retardation layer 324 may ignore the thickness of the intermediate layer between the sub-layers of different retardation layers 324. When the polarization layer 322 may include multiple sub-layers (not shown), an intermediate layer (not shown) may be selectively provided between these sub-layers, for example. Similarly, the thickness of the polarization layer 322 may be obtained by separately measuring the thicknesses of the respective sub-layers in the polarization layer 322 and adding up these sub-layer thicknesses, i.e., the thickness of the polarization layer 322 may ignore the thickness of the intermediate layer between the sub-layers of different polarization layers 322.

[0046] 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, i.e., (T1+T2)<T5. In some embodiments, the thickness range of the optical layer 300 may be from 10 micrometers to 50 micrometers (i.e., 10 micrometers ≤ the thickness of the optical layer 300 ≤ 50 micrometers) or from 20 micrometers to 40 micrometers (i.e., 20 micrometers ≤ the thickness of the optical layer 300 ≤ 40 micrometers). For example, the thickness of the optical layer 300 may be 20 micrometers, 30 micrometers, 45 micrometers, but this is not limited thereto. In some embodiments, the thickness range of the display layer 200, T5, may be from 45 micrometers to 300 micrometers (i.e., 45 micrometers ≤ thickness T5 ≤ 300 micrometers) or from 80 micrometers to 200 micrometers (i.e., 80 micrometers ≤ thickness T5 ≤ 200 micrometers). For example, the thickness T5 of the display layer 200 may be 60 micrometers, 75 micrometers, 110 micrometers, 150 micrometers, 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 may range from 0.3 to 0.6, i.e., 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 damage or peeling problems 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.

[0047] Please refer to Fig.10 , Fig.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. Fig.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 Fig.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. Fig.10 , the extension line L_310e can refer to Fig. 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.

[0048] In summary, according to the rollable display device of the embodiment of the present invention, the structural design of the optical layer and the adhesion layer to attach the optical layer to the display layer can reduce the influence of the stress generated during repeated extension and / or retraction on the film layer in the structure, or adjust the distribution of the stress in the structure to reduce the risk of device damage, improve the function and performance of each layer in the rollable display device, and thus enhance the quality of the rollable display device and its display image.

[0049] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the present invention.

Claims

1. A rollable display device having a normal display state and an extended display state, characterized in that: include: a display layer, wherein when the rollable display device is in the extended display state, the display layer has a larger display area than when the rollable display device is in the normal display state; as well as An optical layer is attached to the display layer through an adhesive layer, and includes a base layer and a functional layer arranged between the base layer and the adhesive layer, wherein the functional layer contacts the adhesive layer, wherein an edge of the adhesive layer is an arc with a curvature radius, and the curvature radius is greater than or equal to 0.4 times the thickness of the adhesive layer and less than or equal to 0.6 times the thickness of the adhesive layer.

2. The rollable display device according to claim 1, characterized in that: The functional layer is formed on the base layer through a multi-pass coating process.

3. The rollable display device according to claim 1, characterized in that: The functional layer includes a polarizing layer and a retardation layer.

4. The rollable display device according to claim 3, characterized in that: The thickness of the polarizing layer is greater than the thickness of the retardation layer.

5. The rollable display device according to claim 3, characterized in that: The polarizing layer includes iodine.

6. The rollable display device according to claim 1, characterized in that: The thickness of the functional layer is smaller than the thickness of the base layer.

7. The rollable display device according to claim 6, characterized in that: The ratio of the thickness of the functional layer to the thickness of the base layer ranges from 0.1 to 0.

8.

8. The rollable display device according to claim 1, characterized in that: The thickness of the base layer is smaller than the thickness of the adhesive layer.

9. The rollable display device according to claim 1, characterized in that: The thickness of the optical layer is smaller than the thickness of the display layer.

10. The rollable display device according to claim 1, characterized in that: The edge of the adhesive layer is more protruding than the edge of the functional layer.

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