Flexible display with layered structure

Abstract

Embodiments relate to a flexible display device comprising a plurality of layers, where each layer is connected to at least another layer at a predetermined location, thereby forming a connection, where the flexible display device is part of a display of an electronic device, and where the flexible display device is connected to the connection. Each of the plurality of layers includes a rotational degree of freedom and slides relative to adjacent layers of the plurality of layers about an axis of folding or curling when the display is folded or curled.

Description

[0001] Related Applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 415,016, filed on October 11, 2010, under 35 U.S.C. § 119, which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure relates to the field of electronic devices, and more particularly to flexible display devices that can be bent, folded, or curled along an axis. Background Art

[0004] The following prior art is cited in this section:

[0005] "In a general rollable display device, a flexible display panel can be rolled on a housing. In this case, excessive stress or breakage may occur in a part of the flexible display panel, and thus defects may occur at pixels provided in a part of the flexible display panel." [U.S. Patent Publication No. US 9,710,020 B2, entitled "Rollable display apparatus"]

[0006] "Specifically, in order to improve user convenience, display devices with relatively small sizes and light weights are being developed.

[0007] As a measure of this trend, foldable or bendable flexible display devices are being actively developed in various types. In addition, ways to further improve the bending strength and flexibility of flexible display devices are being demanded." [U.S. Patent Publication No. US 10,459,489 B2, entitled "Display panel and display apparatus including the same"]

[0008] "A foldable display is a recently developed display that can be very thin and made of solid-state semiconductor devices. In a pre-existing organic light-emitting diode ("OLED") display, the semiconductor device section is typically 100 to 500 nanometers thick and includes at least one organic material layer. The semiconductor device section of an existing display is typically supported by a substrate made of transparent plastic, glass, or very thin metal foil. The main function of the substrate is for manufacturing purposes (for deposition and application of organic layers); otherwise, the substrate does not provide any structural benefits.

[0009] One advantage of OLEDs is their ability to be rolled or folded into a compact shape, which can be beneficial for portable electronic devices, whether handheld smartphones or large-area wall-mounted displays. However, OLEDs do not have the structural stability and rigidity to maintain a flat shape, especially after being folded and / or curled multiple times. As the demand for high-definition displays increases, this inability to maintain flatness can adversely affect their optimal functionality. Common materials for substrates in pre-existing display structures, such as plastics, aluminum, and glass, may not provide sufficient strength, rigidity, and durability without adding bulk to the display structure, which in turn adversely affects the flexibility of OLED displays. [U.S. Patent Publication No. US10280493B2, entitled "Foldable display structures"]

[0010] Accordingly, there is a need for a flexible display device / support structure for a display that has a combination of strength, zero memory, and the ability to accommodate a tight bend radius. SUMMARY OF THE INVENTION

[0011] The following is an overview that provides a basic understanding of one or more embodiments described herein. This overview is not intended to identify key or important elements or to delineate any scope of different embodiments and / or any scope of the claims. The sole purpose of the Summary of the Invention is to present some concepts in a simplified form as a prelude to the more detailed description presented herein.

[0012] In view of the foregoing, the inventors have recognized and appreciated the following advantages: providing improved structural support to OLEDs to provide and enhance their flatness and durability while maintaining their flexibility and ability to be folded or rolled into a compact shape for multiple uses.

[0013] According to an embodiment, it is a flexible display device including multiple layers, wherein each layer is connected to at least one other layer at a predetermined position, thereby forming a connection member, wherein the flexible display device is part of a display of an electronic device, and wherein each layer of the multiple layers includes a degree of rotational freedom and slides relative to an adjacent layer of the multiple layers about an axis of folding or curling when the display is folded or curled.

[0014] According to an embodiment of the flexible display device, each layer of the multiple layers includes a material having an elastic limit with at least 1.5% strain.

[0015] According to an embodiment of the flexible display device, a flexible silica glass surface forms a first surface layer facing the display side and is supported by a second surface layer having an amorphous sheet.

[0016] According to an embodiment of the flexible display device, the amorphous sheet includes silica or an alloy.

[0017] According to an embodiment of the flexible display device, an organic light-emitting diode (OLED) is printed on the surface of flexible silica glass.

[0018] According to an embodiment of the flexible display device, the surface of the flexible silica glass is firmly bonded to one or more layers of amorphous alloy along the flexible region.

[0019] According to an embodiment of the flexible display device, the surface of the flexible silica glass is firmly bonded to one or more layers of silica along the flexible region.

[0020] According to an embodiment of the flexible display device, at least one of the plurality of layers includes an amorphous material.

[0021] According to an embodiment of the flexible display device, the amorphous material includes an iron-based amorphous strip.

[0022] According to an embodiment of the flexible display device, the amorphous material includes a silica-based glass sheet.

[0023] According to an embodiment of the flexible display device, the plurality of layers of the flexible display device form a spring structure.

[0024] According to an embodiment of the flexible display device, the iron-based amorphous strip includes iron in the first range of 84% - 100%, silicon in the second range of 0 - 10%, boron in the third range of 0 - 5%, and manganese in the fourth range of 0 - 2%.

[0025] According to an embodiment of the flexible display device, the iron-based amorphous strip includes iron in the first range of 0 - 100%, cobalt in the second range of 0 - 85%, nickel in the third range of 0 - 50%, silicon in the fourth range of 0 - 10%, molybdenum in the fifth range of 0 - 8%, boron in the sixth range of 0 - 5%, and manganese in the seventh range of 0 - 2%.

[0026] According to an embodiment of the flexible display device, the amorphous material includes an amorphous alloy having an elastic strain limit of at least 1.5%, and the amorphous alloy is selected from: (Zr,Ti) a (Ni,Cu,Fe) b (Be,Al,Si,B) c , where a = 30 - 75, b = 5 - 60, and c = 0 - 50 in atomic percentages; (Zr,Ti) a (Ni,Cu) b (Be) c , where a = 40 - 75, b = 5 - 50, and c = 5 - 50 in atomic percentages; (Zr,Ti)a (Ni, Cu) b (Be) c , wherein a = 40 - 65, b = 7.5 - 35, and c = 10 - 37.5 in atomic percentages; and (Zr) a (Nb, Ti) b (Ni, Cu) c (Al) d , wherein a = 45 - 65, b = 0 - 10, c = 20 - 40, and d = 7.5 - 15 in atomic percentages.

[0027] According to an embodiment of the flexible display device, the amorphous alloy includes an amorphous alloy of Zr-based, Ti-based, Zr-Ti-based, Fe-based, or a combination thereof.

[0028] According to an embodiment of the flexible display device, the amorphous alloy is at least substantially free of Be.

[0029] According to an embodiment of the flexible display device, the amorphous alloy further includes a plurality of crystalline precipitates.

[0030] According to an embodiment of the flexible display device, at least one of the plurality of layers includes a plurality of structural components, the plurality of structural components including wires, strips, fibers, tapes, or a combination thereof, wherein the plurality of structural components are configured to provide structural stability and rigidity to maintain a flat shape of the display after the display is folded and opened or curled and unrolled multiple times.

[0031] According to an embodiment of the flexible display device, the plurality of structural components include a series of horizontally aligned strips.

[0032] According to an embodiment of the flexible display device, the plurality of structural components include a grid of horizontally and longitudinally aligned fibers.

[0033] According to an embodiment of the flexible display device, at least one of the plurality of structural components includes (i) a fiber having a diameter of about 0.01 mm to about 0.5 mm or (ii) a tape having a thickness of about 0.023 mm and a width of about 2 mm to about 213 mm.

[0034] According to an embodiment of the flexible display device, the connecting member is a rigid connecting member.

[0035] According to an embodiment of the flexible display device, the connecting member includes a mechanical connecting member, the mechanical connecting member including one of spot welding, fastening connecting members, and rivets.

[0036] According to an embodiment of the flexible display device, the connecting member includes a mechanical connecting member, the mechanical connecting member including a telescopic sliding connecting member.

[0037] According to an embodiment of the flexible display device, a predetermined position is configured such that changing the predetermined position changes the degree of free sliding.

[0038] According to an embodiment of the flexible display device, the display includes at least one organic light emitting diode; at least one of the plurality of layers includes at least one amorphous alloy; and wherein the display remains at least substantially flat after being folded and opened multiple times.

[0039] According to an embodiment of the flexible display device, the flexible display device is part of one or more of a mobile phone, a smart phone, a personal digital assistant, a computer, a television, a wall-mounted display.

[0040] According to an embodiment of the flexible display device, each of the plurality of layers has a different thickness.

[0041] According to an embodiment of the flexible display device, each of the plurality of layers has the same thickness.

[0042] According to an embodiment of the flexible display device, a first layer closest to the display side among the plurality of layers is different from a second layer farthest from the display side among the plurality of layers, the first layer has a first thickness, the second layer has a second thickness, wherein the first thickness is less than the second thickness, and wherein the elastic limits of the first material of the first layer and the second material of the second layer are at least 1.5% strain.

[0043] According to an embodiment of the flexible display device, a lubricating mechanism is positioned between adjacent layers, the lubricating mechanism is configured to reduce friction and facilitate free movement of the layers relative to each other.

[0044] According to an embodiment of the flexible display device, the lubricating mechanism includes a dry lubricant.

[0045] According to an embodiment of the flexible display device, the lubricating mechanism includes a liquid lubricant, and the liquid lubricant is contained in a sealed channel between adjacent layers.

[0046] According to an embodiment of the flexible display device, a magnetic field is used to hold the plurality of layers in a stable position until sufficient force is applied to release the layers.

[0047] According to an embodiment, it is a display including a flexible display device, wherein the flexible display device includes a plurality of layers, wherein each layer is connected to at least one other layer at a predetermined position, thereby forming a connection member, and wherein each of the plurality of layers includes a degree of rotational freedom and slides relative to an adjacent layer among the plurality of layers about an axis of folding or curling when the display is folded or curled.

[0048] According to an embodiment of the display, the display is operable as a secondary display of an electronic device.

[0049] According to an embodiment of the display, the display can operate as an extension of an existing display for an electronic device.

[0050] According to an embodiment of the display, the display can operate to be connected via a wireless connection or a wired connection.

[0051] According to an embodiment of the display, the display can operate to be interconnected with a second display having similar properties to form a continuous display.

[0052] According to an embodiment of the display, the display can operate for wireless charging.

[0053] According to an embodiment of the display, the display is a touch-sensitive display.

[0054] According to an embodiment, there is a manufacturing method, including: selecting layers based on a predetermined thickness of a flexible display device to form a plurality of layers; selecting the thickness of each layer in the plurality of layers; selecting a material for each layer such that the elastic strain limit of the material is at least 1.5%; positioning the layers in a desired configuration; and firmly connecting the layers such that each layer is connected to at least one other layer at a predetermined position, thereby forming a connecting member; and wherein the flexible display device is part of a display of an electronic device; and wherein each layer in the plurality of layers includes a degree of rotational freedom and slides relative to an adjacent layer in the plurality of layers about an axis of folding or curling when the display is folded or curled.

[0055] According to an embodiment of the manufacturing method, the connecting member is a rigid connection point.

[0056] According to an embodiment of the manufacturing method, the connecting member includes a mechanical connecting member, and the mechanical connecting member includes one of spot welding, fastening connecting members, and rivets.

[0057] According to an embodiment of the manufacturing method, the connecting member includes a mechanical connecting member, and the mechanical connecting member includes a telescopic sliding connecting member. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Aspects of the present invention will now be described in more detail with reference to the drawings showing exemplary embodiments of the invention, in which:

[0059] Figure 1A A foldable screen / display of a smartphone according to an embodiment is shown.

[0060] Figure 1B A rolled-up screen / display according to an embodiment is shown.

[0061] Figure 1C A crease surface along a flexure zone of a current foldable display in the market according to an embodiment is shown.

[0062] Figure 2Shows the strain of a single spring on the inner and outer surfaces according to an embodiment.

[0063] Figure 3 Shows a single solid spring and the strain on the inner and outer surfaces according to an embodiment.

[0064] Figure 4 Shows a layered spring and the strain on the inner and outer surfaces according to an embodiment.

[0065] Figure 5 Shows a table comparing the strain in a solid spring and a layered spring according to an embodiment.

[0066] Figure 6 Shows a first example of a layered pattern for a support structure according to an embodiment.

[0067] Figure 7 Shows a second example of a layered pattern for a support structure according to an embodiment.

[0068] Figure 8 Shows a first example of the chemical properties of an iron (Fe)-based amorphous ribbon according to an embodiment.

[0069] Figure 9 Shows a second example of the chemical properties of an iron (Fe)-based amorphous ribbon according to an embodiment.

[0070] Figure 10 Shows the dimensions of commercially available iron (Fe)-based amorphous ribbons according to an embodiment.

[0071] Figure 11 Shows the properties of silica glass according to an embodiment through the characteristics.

[0072] Figure 12 Shows a rollable / foldable screen that can be used as an extension of an existing smartphone screen according to an embodiment.

[0073] Figure 13 Shows a rollable / foldable screen that can be used as an extension of an existing screen according to an embodiment.

[0074] Figure 14 Shows a rollable / foldable screen according to an embodiment, which can be used as an extension in various scenarios and for applications.

[0075] Figure 15 Shows a transverse cross-sectional view schematically showing the internal structure of a display device according to an embodiment.

[0076] Figure 16Illustrated is a display panel that is touchable in a display device having a flexible structure according to an embodiment.

[0077] Figure 17 A schematic diagram of a first exemplary foldable display structure according to an embodiment is shown.

[0078] Figure 18 A schematic diagram of a second exemplary foldable display structure according to an embodiment is shown.

[0079] Figure 19 A schematic diagram of a third exemplary foldable display structure according to an embodiment is shown. Detailed Description

[0080] Definitions and General Techniques

[0081] For simplicity and clarity of illustration, these figures illustrate the general manner of construction. Descriptions and details of well-known features and techniques may be omitted from the description and the drawings to avoid unnecessarily obscuring the present disclosure. Some elements may be drawn larger in size relative to other elements in the drawings to help improve understanding of the embodiments of the present disclosure. The same reference numerals in different drawings denote the same elements.

[0082] Although the detailed description herein contains many details for the purpose of illustration, those of ordinary skill in the art will understand that many variations and changes to the details are considered to be included herein.

[0083] Accordingly, the embodiments herein are not loss of generality and do not limit any of the claims set forth herein. The terms used herein are for the purpose of describing particular embodiments only and are not limiting. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0084] The invention may be embodied in other specific forms without departing from its spirit or characteristics. The described embodiments are illustrative in all respects and not restrictive. Accordingly, the appended claims (rather than the description herein) indicate the scope of the invention. All variations that fall within the meaning and scope of the equivalents of the claims are within its scope.

[0085] Although this specification contains many details, these details are not to be construed as limiting the scope of the disclosure or the claims, but rather as describing features of particular implementations. A single implementation may implement certain features described in this specification in the context of separate implementations. Conversely, multiple implementations may, individually or in any suitable sub-combination, implement different features described herein in the context of a single implementation. Moreover, although the features described herein operate in certain combinations and are even claimed as such initially, in some cases, one or more features from a claimed combination may be deleted from the combination, and the claimed combination may cover a sub-combination or a variation of a sub-combination.

[0086] Similarly, although the operations depicted in the figures herein are shown in a particular order to achieve desired results, this should not be construed as requiring that the operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed to achieve the desired results. In some cases, multitasking and parallel processing may be advantageous. Moreover, the separation of different system components in an implementation should not be construed as requiring such separation in all implementations, and it should be understood that the described program components and systems may be integrated together in a single software product or packaged into multiple software products.

[0087] Even though particular combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of possible implementations. Other implementations are within the scope of the claims. For example, the acts recited in the claims may be performed in a different order and still achieve the desired results. In fact, many of these features may be combined in ways not specifically recited in the claims and / or disclosed in the specification. Although each dependent claim may directly depend on only one claim, the disclosure of possible implementations includes each dependent claim in combination with every other claim in the claim set.

[0088] The present disclosure may be embodied in other specific forms without departing from its spirit or characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. Thus, the scope of the present disclosure is indicated by the appended claims rather than by the foregoing description. All changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.

[0089] Unless otherwise defined herein, scientific and technical terms used in connection with the present disclosure shall have the meanings commonly understood by one of ordinary skill in the art. Moreover, unless the context otherwise requires, the singular terms shall include the plural and the plural terms shall include the singular.

[0090] Unless otherwise indicated, the following terms and phrases shall be understood to have the following meanings.

[0091] As used herein, the articles "a" and "an" as used herein refer to one or more than one (i.e., at least one) grammatical object of the article. By way of example, "an element" means one element or more than one element. Further, unless otherwise specified or clear from the context, the use of the articles "a" and "an" in the specification and the drawings is construed to mean "one or more" and refers to the singular form.

[0092] As used herein, the terms "example" and / or "exemplary" mean serving as an example, instance, or illustration. To avoid doubt, such examples do not limit the subject matter described herein. Further, any aspect or design described herein as "example" and / or "exemplary" is not necessarily superior or advantageous to other aspects or designs, nor does it exclude equivalent exemplary structures and techniques known to those of ordinary skill in the art.

[0093] As used herein, the terms "first", "second", "third", etc. (if any) in the specification and the claims distinguish similar elements and do not necessarily describe a particular sequence or temporal order. In appropriate circumstances, these terms are interchangeable such that embodiments of the present disclosure, for example, can operate in sequences other than those illustrated or otherwise described herein. Further, the terms "include", "have" and any variations thereof cover non-exclusive inclusion such that a process, method, system, article, device or apparatus that includes a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, system, article, device or apparatus.

[0094] As used herein, the terms "left", "right", "front", "back", "top", "bottom", "above", "below", etc. (if any) in the specification and the claims are for descriptive purposes and do not necessarily describe a permanent relative position. The terms used herein are interchangeable in appropriate circumstances such that embodiments of the apparatus, method, and / or article described herein, for example, can operate in other orientations different from those illustrated or otherwise described herein.

[0095] Any element act or instruction used herein is not critical or essential unless expressly so described. Additionally, the term "group" includes items (e.g., related items, unrelated items, combinations of related and unrelated items, etc.) and may be interchangeable with "one or more". When only one item is intended, the term "a" or similar language is used. Also, the terms "has", "have", "having", etc. are open-ended terms. Further, unless otherwise expressly stated, the phrase "based on" means "at least partially based on".

[0096] As used herein, the terms "couple", "coupled", "couples", "coupling", etc. mean to connect two or more elements mechanically, electrically, and / or otherwise. Two or more electrical elements may be electrically coupled together but not mechanically or otherwise coupled together. A coupling can last for any duration, e.g., permanently or semi-permanently or only for an instant. "Electrically coupled" includes all types of electrical couplings. The words "removably", "removable", etc. not being present near the word "couple", etc. does not mean that the coupling, etc. being discussed is removable or non-removable.

[0097] As used herein, the terms "system", "device", "unit", and / or "module" refer to different components, component parts, or assemblies of different levels in that order. However, other expressions that achieve the same purpose may replace these terms.

[0098] As used herein, the term "or" means inclusive "or" rather than exclusive "or". That is, unless otherwise specified or clear from the context, "X employs A or B" means any natural inclusive arrangement. That is, if X employs A; X employs B; or X employs both A and B, then in any of the foregoing cases, "X employs A or B" is satisfied.

[0099] As used herein, the term "substantially" may refer to within a specified or unspecified range of a specified or unspecified stated value. In some embodiments, "substantially" may mean within ±10% of the stated value. In other embodiments, "substantially" may mean within ±5% of the stated value. In additional embodiments, "substantially" may mean within ±3% of the stated value. In still other embodiments, "approximate" may mean within ±1% of the stated value.

[0100] As used herein, two or more elements or modules are "integral" or "integrated" when they operate together functionally. Two or more elements are "non-integral" if each element can operate functionally independently.

[0101] It will be understood that when an element, layer, region or component is referred to as being "on", "connected to" or "coupled to" another element, layer, region or component, it can be directly on, connected or coupled to the other element, other layer, other region, other component, or there can be one or more intervening elements, layers, regions or components. However, "directly connected / coupled" means that one component is directly connected or coupled to another component without an intervening component. At the same time, other expressions describing the relationship between components, such as "between", "directly between" or "adjacent to" and "directly adjacent to", can be similarly interpreted. In addition, it should also be understood that when referring to an element or layer "between" two elements or layers, it can be the only element or layer between the two elements or layers, or it is not the only element, and one or more intervening elements or layers can also be present between the two elements or layers.

[0102] As used herein, the term "fold" refers to the action of bending or wrinkling a flexible display screen along a specific axis or hinge point to change its form factor. A foldable display is designed to be flexible and capable of being repeatedly folded or opened without damaging the screen or affecting its functionality. This flexibility allows the display to switch between different configurations, such as a traditional flat screen mode and a folded mode where the screen is partially or fully bent.

[0103] As used herein, the term "roll" refers to the action of winding or rolling up a flexible display screen around a cylindrical or rollable core or shaft. A rollable display will be designed to be flexible and capable of being repeatedly rolled and unrolled without damaging the screen or affecting its functionality. This flexibility allows the display to switch between different form factors, such as a traditional flat screen mode and a rolled-up mode where the display is compactly stored or partially rolled, thus providing convenience and portability to the user.

[0104] The term "hysteresis" refers to the phenomenon where the response of a material to an external force or stimulus is delayed or lags behind the cause of the stimulus. In other words, the behavior of the material depends not only on the current stimulus but also on its past history. For example, in the context of stress and strain in a material, hysteresis is observed when the stress-strain curve for loading (increasing stress) is different from the curve for unloading (decreasing stress). This difference indicates that when the load is removed, the material does not return to its initial state; it retains some deformation or memory of the past load.

[0105] In the context of flexure cycling, the term "hysteresis loss" refers to the energy dissipation or loss that occurs when a material or component is subjected to repeated flexure or bending. This loss occurs because not all of the energy applied to deform the material during each cycle is recovered when the material returns to its initial shape. Instead, some of the energy is converted into heat or other forms of internal energy within the material.

[0106] The term "zero memory" refers to a material or system that returns to its initial state or position after being subjected to an external force or deformation. In this context, "zero memory" indicates that there is no hysteresis or lag in the response of the material, and it returns precisely or nearly to its initial conditions. Shape memory alloys, such as Nitinol, are exceptions when using the term "zero memory". In these materials, when heated above a certain temperature (austenite finish temperature), they return precisely to their original shape after deformation, exhibiting minimal hysteresis.

[0107] As used herein, the term "display structure" or "support structure" refers to the structure that provides stiffness in a flexible display and is also referred to as the "substrate" or "backplane". The choice of material for the substrate or backplane is crucial because it needs to be rigid to maintain the structural integrity of the display while still allowing a certain degree of flexibility. In the present disclosure, this is also referred to as the display device.

[0108] Definitional problem: Since smartphones have effectively taken over many traditional functions of computers, the amount of information that can be viewed is limited by the size of the display. It is expected that the global average functionality will increase significantly over the next 20 years, which will require a larger display size.

[0109] Not suitable for most pockets and wallets. Even most smartphones are already in the 6" to 7" screen size range.

[0110] The need for a display with a variable geometry that can be easily folded or rolled up and still opened to the size of is the ultimate holy grail.

[0111] Current organic light-emitting diode (OLED) displays develop memory when repeatedly hinged and, as shown in the latest phones, this memory results in visible wrinkles along the curved surface.

[0112] Currently, the materials supporting OLED displays do not have a combination of strength, zero memory, and most importantly, the ability to accommodate a tight bending radius of less than 2.0 mm.

[0113] Flexible display (FD) devices can be divided into two categories: (i) two rigid surfaces connected by flexible zones and (ii) a single large surface that can be rolled up.

[0114] Two rigid surfaces connected by a flexible region: Figure 1A A foldable screen / display of a smartphone according to an embodiment is shown. A large display folded along a limited flexible region, similar to those currently on the market phones. This function of the flexible region is that of a hinge, and the radius of the flexible surface can be from 1.5 mm to 3.0 mm.

[0115] One large surface that rolls up: Figure 1B A rolled-up screen / display according to an embodiment is shown. Another application is a display that rolls up with a radius from 10.0 mm to 30.0 mm. Since the display also serves as an input device with a touchpad function, a certain level of structural integrity and an ultra-thin geometry are necessary.

[0116] Figure 1C A creased surface along the flexure region of a current foldable display in the market according to an embodiment is shown. The display reveals a creased surface 110 along the flexible region. This flexure region is also prone to cracking.

[0117] The support structure behind the OLED display must satisfy three key characteristics:

[0118] i. Maximum volumetric strength.

[0119] ii. Close to ZERO memory or hysteresis loss through bending cycles.

[0120] iii. Available in sheet or foil thickness:

[0121] ○ Between 0.02 mm and 0.05 mm, for folding of two flat surfaces (similar to an SS phone).

[0122] ○ Between 0.1 mm and 0.5 mm, for a rolled-up display.

[0123] The flexible support structure must have sufficient strength to hinge the OLED and other support brackets and surfaces to a flat position and be able to provide sufficient structural integrity to accommodate the touchscreen function. Amorphous alloys have a 10x strength-to-volume advantage over silica glass and a 2x strength-to-volume advantage over silica glass. As shown herein, the volume (density) and strain limit have a linear effect on the achievable bending radius. Thus, the strength-to-weight ratio greatly favors foils made of amorphous alloys.

[0124] Amorphous alloys have perfect memory and no hysteresis loss. This allows the entire hinged surface to return to its initial position.

[0125] A single thick amorphous sheet can function well to maintain a flat surface and structural rigidity. However, since the amorphous metal sheet has an elastic limit of approximately 2.0%, the strain load on the outer surface is proportional to the radius of the curve relative to "t" (the thickness of the spring). In an embodiment, the combined thickness of the layered structure can total up to 0.1 mm to 5.0 mm. As an example, it is possible that a single amorphous body sheet with a thickness of 0.5 mm or an amorphous body alloy foil with a thickness of 0.1 mm may be difficult to curl when added in multiple layers to form a support structure. Therefore, the thickness of the individual layers can be selected such that the thickness of the individual layers is between 0.01 mm and 0.1 mm, forming a combined flexible support structure thickness in the range of 0.01 mm to 5.0 mm. In an embodiment, there may be other materials between the layers of the multiple layers that can affect the overall thickness / combined thickness or size of the support structure. In an embodiment, the thickness of the individual layers can be selected such that the individual layer thickness is between 0.01 mm and 0.2 mm, thereby forming a combined flexible support structure thickness in the range of 0.02 mm to 5.0 mm. In an embodiment, the flexible support structure has at least two layers.

[0126] In an embodiment, it is a flexible display having a layered spring structure that uses an amorphous alloy capable of connecting to multiple devices.

[0127] The strain on the outer surface of the flat spring is linear with the thickness of the sheet. Figure 2 The strain of a single spring on the inner and outer surfaces according to an embodiment is shown. As Figure 2 shown, the strain of a single spring is the difference between the lengths of the inner and outer circles.

[0128] 1 The length of a 1 / 2 circle (circumference of a semi - circle) = radius * π.

[0129] The thickness of the spring becomes a key determinant. Since the elastic limit of most amorphous alloys can be about 2%, the formula given below applies:

[0130] Spring height (t) ≤ radius * 0.02

[0131] where 't' represents the thickness of the spring when the inner surface is in compression and the outer surface is in tension, acting as a fulcrum and being linearly and directly proportional to the amount of stress applied to the outer surface when the spring bends around a radius. Therefore, it can be concluded that when less than 2% of the required bending radius, the thickness of the spring (flat sheet / strip) will maintain the strain in the outer layer within the 2% elastic strain limit. Given the above relationship, if the desired strain limit is not 2% or the bending radius for a given thickness limits the elastic strain limit to a certain desired percentage, the thickness can be obtained.

[0132] A spring is an elongated, flat, and flexible strip of material that can be bent or flexed under load.

[0133] Figure 3 Shown are a single solid spring and the strains on the inner and outer surfaces according to an embodiment. Consider a solid spring with a thickness of 1.00 mm bent to a radius of 10 mm. The innermost layer 301 will have a bending radius of 10 mm, while the outermost layer 302 will have a bending radius of 11 mm. The outermost layer 302 will undergo the maximum strain. Thus, the circumference of the inner surface 301 will be 10π, which is equal to 31.41 mm, and the circumference of the outer surface 302 will be 11π, which is equal to 34.55 mm.

[0134] It is the 5×2% strain limit. The 2% strain limit is typically the elastic strain limit for most materials. The elastic limit is the maximum stress that a material can withstand without sustaining permanent deformation. This is the point on the stress-strain curve beyond which the material cannot return to its initial shape when the stress is removed. For example, if a material has an elastic limit of 0.2% strain or an elastic strain limit of 0.2%, this means that the material can undergo a deformation of up to 0.2% of its original length or dimensions and still recover its original shape and size when the applied stress is removed. In other words, if a material has an elastic limit of 0.2% strain and it has an original length of 100 mm, then the material can undergo a deformation of 0.2 mm before plastic deformation begins.

[0135] As an example, stainless steel has an elastic strain limit of 0.2% - 0.4% strain; thin metal foils of copper and aluminum can have an elastic strain limit in the range of 1% - 3% strain. Plastic OLED substrates can have an elastic strain limit of up to 3% strain; polyethylene terephthalate (PET) can have an elastic strain limit of about 1% - 2% strain; organic light-emitting diode (OLED) displays integrated into flexible substrates can have an elastic strain limit of about 1%.

[0136] Figure 4 Shown are a layered spring and the strains on the inner and outer surfaces according to an embodiment. Consider a layered spring with 10 layers, each 0.1 mm thick and a total thickness of 1.00 mm, bent to a radius of 10 mm. The innermost surface of the innermost layer 401 will have a bending radius of 10 mm, while the outermost surface of the outermost layer 402 will have a bending radius of 11 mm. For the outermost layer 402, the inner surface circumference will be 10.9π, which is equal to 34.24 mm, and the outer surface circumference will be 11π, which is equal to 34.55 mm.

[0137]

[0138] It is the 5×2% strain limit. The 2% strain limit is typically the elastic strain limit of most materials.

[0139] Therefore, compared with a single solid structure, the layered structure has an advantage in restricting the strain on the surface subjected to a tight bending radius. Thus, materials (stainless steel with an elastic strain limit of 0.2%-0.4% strain; thin metal foils of copper and aluminum with an elastic strain limit in the range of 1%-3% strain; plastic OLED substrates with an elastic strain limit of up to 3% strain; polyethylene terephthalate (PET) with an elastic strain limit of approximately 1%-2% strain; organic light-emitting diode (OLED) displays integrated into a flexible substrate with an elastic strain limit of approximately 1%) can function properly when incorporated into the layered structure. In addition, as can be seen from the calculations described herein, the material selection can depend on the bending radius of the support structure and the thickness of the selected layer (based on the number of layers selected to provide the total thickness).

[0140] Figure 5 A table showing the comparison of strain in a solid spring and a layered spring according to an embodiment is shown. Figure 5 The calculation of the strain on a leaf spring is shown. The leaf spring is a solid leaf spring with a thickness of 1 mm and a bending radius of 10 mm, compared with a layered spring. The layered spring has 5 layers, each with a thickness of 0.2 mm. As explained herein and as shown in the calculation of the table presented in Figure 5 the strain in the outermost layer in the layered spring is minimized compared with the solid spring without layers.

[0141] Defined scheme: By stacking multiple layers of amorphous sheets that can slide freely relative to each other, the 'r' value can be reduced while maintaining the structural integrity and durability.

[0142] The thickness of the amorphous spring and the radius of the flexible display: The thickness of the spring is less than 2% of the desired radius. When less than 2% of the required bending radius, the thickness of the spring will keep the strain in the outer layer within the 2% elastic strain limit. For example, if the desired radius is 5.0 mm, the thickness of the amorphous sheet needs to be less than 0.1 mm thick. An amorphous spring of this thickness does not have sufficient strength to provide the desired structural stability and the strength to rebound to a consistent flat position. If the thickness of the spring is increased to overcome these weaknesses, the spring is likely to experience rupture before the desired timeline.

[0143] One way to achieve both a 0.1 mm thickness and structural stability and flexibility of a spring is to use thin sheets and stack them within a total thickness of less than or equal to 0.1 mm while allowing those layers and surfaces to slide against each other. These layers provide strength and stiffness for the combined height of the entire layer, but the strain generated on the outer surface decreases in proportion to the number of layers used. The fulcrum for determining the strain on the outer surface starts at the inner surface of each layer. The thin sheets can be amorphous materials. Figure 6 A first example of a layered pattern for a support structure for a display device according to an embodiment is shown. A plurality of layers are connected at a flexible line where the display will be bent, and the remaining portions of the surfaces of these layers are allowed to move freely (i.e., slide) when the display is folded or rolled up. The top layer 602 faces the display side of the device and is the inner layer.

[0144] Figure 7 A second example of a layered pattern of a support structure / display device according to an embodiment is shown. Another way to implement a layered display device support structure is to join a plurality of layers at predetermined points. These points can be as Figure 7 shown, which will limit stress and thus limit the strain on the outermost surface when bent. Consider other configurations for connecting a plurality of layers, where it is required that the plurality of layers form a sufficient support structure for the display, and each layer will slide freely on other surfaces when connected at predefined positions. The top layer 702 faces the display side of the device and is the inner layer.

[0145] The connection at a predetermined position is advantageous because it provides a simple and robust connection that can accommodate movement and reduce stress. Predetermined means a position or point that has been intentionally selected or specified in advance, at which the layers are joined or connected. These positions are not random, but are carefully selected and designed such that controlled and planned movement can occur between the layers. These connection points are determined based on the desired function and expected movement of the structure. By connecting the layers at predetermined points, the layers can slide or move freely on each other in a controlled and predictable manner. As Figure 6 shown, the connection can be along a flexible line, at the center of the strip 603, rigidly connecting all layers, for example, layers L1, L2, ……, L5, and allowing the remaining portions of the unconnected areas to slide freely relative to adjacent layers. L1 can be the layer closest to the display. In an embodiment, the layers can be arranged as Figure 7 shown. These layers can be formed by a plurality of strips in each layer. For example, layer L2 is formed by two separate strips. Layer L1 is connected to L2 and L3, L2 is connected to L1, and L3 is connected to L4 and L5 (L4 is connected to L3), and so on. As Figure 6 and 7The arrangement of the layers shown is an example, and many such forms can be designed, requiring that the layers must slide over one another, cover a given area, provide sufficient support, and the elastic strain limit in the layers is within 1.5% to 2%. In an embodiment, there may be positions that can provide support points between the layers, but these support points do not rigidly connect the two layers. They can be connected to one layer and rest on other layers, thus providing support while allowing the layers to slide over one another. According to an embodiment, the connection can be a point or spot connection or a continuous connection along a line connecting two surfaces or layers. Each layer L1, L2, etc. has a separate thickness and the flexible display support structure or device has an overall or combined thickness. In an embodiment, the combined thickness may or may not be equal to the sum of the individual layers because there may be other materials between the layers that affect the combined dimensions. The other materials can be electronic components, lubricating materials, etc.

[0146] The laminated spring should consist of separate layers, each layer being capable of bending independently and sliding or curling along the surface of an adjacent layer about a bending axis or a rolling axis. If we have a laminated spring in which all the layers have interconnected surfaces that behave like a single solid spring or a solid plate when bent, it should not be classified as a true laminated spring.

[0147] According to an embodiment, it is a flexible display device including a plurality of layers, wherein each layer is connected to at least one other layer at a predetermined position, thereby forming a connection member, wherein the flexible display device is part of a display of an electronic device, and wherein when the display is folded or curled, each layer of the plurality of layers includes a degree of rotational freedom and slides relative to an adjacent layer of the plurality of layers about the axis of folding or curling.

[0148] According to an embodiment of the flexible display device, each layer of the plurality of layers includes a material having an elastic strain limit of at least 1.5%. According to an embodiment of the flexible display device, a flexible silica glass surface forms a first surface layer facing the display side and is supported by a second surface layer having an amorphous sheet. According to an embodiment of the flexible display device, a flexible silica glass surface forms a first surface layer facing the display side and is supported by a second surface layer having a material with an elastic limit of at least 1%. According to an embodiment of the flexible display device, each layer of the plurality of layers includes a material having an elastic limit of at least 1%.

[0149] According to an embodiment of the flexible display device, the amorphous sheet includes silica or an alloy. According to an embodiment of the flexible display device, an organic light-emitting diode (OLED) is printed on the flexible silica glass surface.

[0150] According to an embodiment of the flexible display device, the flexible silica glass surface is firmly bonded to one or more amorphous alloy layers along the flexible region. According to an embodiment of the flexible display device, the flexible silica glass surface is firmly bonded to one or more layers of silica along the flexible region.

[0151] According to an embodiment of the flexible display device, at least one of the plurality of layers includes an amorphous material. According to an embodiment of the flexible display device, the amorphous material includes an iron-based amorphous strip. According to an embodiment of the flexible display device, the amorphous material includes a silica-based glass sheet. According to an embodiment of the flexible display device, the plurality of layers of the flexible display device form a spring structure.

[0152] According to an embodiment of the flexible display device, a magnetic field is used to hold the plurality of layers in a stable position until sufficient force is applied to release the layers.

[0153] According to an embodiment of the flexible display device, the connecting member is a rigid connecting member. According to an embodiment of the flexible display device, the connecting member includes a mechanical connecting member, and the mechanical connecting member includes one of a spot weld, a fastening connecting member, and a rivet. According to an embodiment of the flexible display device, the connecting member includes a mechanical connecting member, and the mechanical connecting member includes a telescopic sliding connecting member.

[0154] According to an embodiment of the flexible display device, the predetermined position is configured such that changing the predetermined position changes the degree of free sliding. The predetermined position is the position where two layers are joined. It can be based on stiffness and sliding freedom as needed. According to an embodiment of the flexible display device, the display includes at least one organic light-emitting diode; wherein, at least one of the plurality of layers includes at least one amorphous alloy; and wherein, the display remains at least substantially flat after being folded and opened multiple times.

[0155] According to an embodiment of the flexible display device, the flexible display device is part of one or more of a mobile phone, a smartphone, a personal digital assistant device, a computer, a television, a wall-mounted display. According to an embodiment of the flexible display device, each of the plurality of layers has a different thickness. According to an embodiment of the flexible display device, each of the plurality of layers has the same thickness. According to an embodiment of the flexible display device, the first layer closest to the display side among the plurality of layers is different from the second layer away from the display side. The first layer has a first thickness, and the second layer has a second thickness. Wherein, the first thickness is less than the second thickness, and the elastic limits of the first material of the first layer and the second material of the second layer are at least 1.5% strain.

[0156] According to an embodiment of a flexible display device, a lubricating mechanism is positioned between adjacent layers, and the lubricating mechanism is configured to reduce friction and facilitate free movement of the layers relative to each other. According to an embodiment of the flexible display device, the lubricating mechanism includes a dry lubricant. According to an embodiment of the flexible display device, the lubricating mechanism includes a liquid lubricant, and the liquid lubricant is accommodated in a sealed channel between adjacent layers.

[0157] In an embodiment, it is a flexible display with a layered spring. In an embodiment, it is a structure using an amorphous alloy that can be connected to multiple devices. In an embodiment, the amorphous sheet can be fixed at various points to reinforce regions as needed while allowing the layers to move freely to form a layered structure to be used in a display.

[0158] In an embodiment, the layered structure forms a hinged portion of the support structure. The hinge portion of the flexible display refers to a specific region or component within the device that allows the display screen to flex, bend, or fold.

[0159] Variable thickness and geometry of the amorphous layer: The inner layer bent around the minimum radius can be thinner. As long as the 2% strain rule is followed, the thickness of the subsequent support layer can be increased. This can help increase structural stability while maintaining the desired durability. It is conceivable that other materials can also be used as long as the relationship between the spring, the bending radius of the sheet, and the thickness results in an elastic strain limit according to the material properties. Another way of processing with the selected material is to obtain the thickness given the material properties and the bending radius.

[0160] It is possible to laminate flexible silica glass sold by ( glass) to provide the same benefits as the amorphous alloy sheet. However, silica glass cannot match the ultimate strength of a specific volume of amorphous alloy. Since the tightness of the curl radius is a key factor, the layered spring structure made of silica glass may be limited to rolled-up displays with a relatively large diameter.

[0161] Figure 8 A first example of the chemical properties of an iron (Fe)-based amorphous strip according to an embodiment is shown. In an embodiment, the iron-based amorphous strip can be used for a layer of the display structure. In Figure 8 the chemical properties of the iron-based amorphous strip are provided.

[0162] Figure 9 A second example of the chemical properties of an iron (Fe)-based amorphous strip according to an embodiment is shown. In an embodiment, an iron-based amorphous strip with chemical / composition different from that Figure 8 shown can be used for a layer of the display structure. The chemical properties of the iron-based amorphous strip can be as Figure 9 shown.

[0163] According to an embodiment of the flexible display device, the iron-based amorphous ribbon includes iron in a first range of 84%-100%, silicon in a second range of 0-10%, boron in a third range of 0-5%, and manganese in a fourth range of 0-2%.

[0164] According to an embodiment of the flexible display device, the iron-based amorphous ribbon contains iron in a first range of 0-100%, cobalt in a second range of 0-85%, nickel in a third range of 0-50%, silicon in a fourth range of 0-10%, molybdenum in a fifth range of 0-8%, boron in a sixth range of 0-5%, and manganese in a seventh range of 0-2%.

[0165] Figure 10 The dimensions of commercially available iron (Fe)-based amorphous ribbons according to an embodiment are shown. The commercially available amorphous ribbons can be used to form the display device structure. The thickness can be in the range of / about 23 microns. In an embodiment, the thickness can be in the range of 0.1 micron to 1 millimeter (mm). In an embodiment, the lower limit of the thickness can be in the range of 0.1 micron to 0.5 mm. In an embodiment, the upper limit of the thickness can be in the range of 0.3 micron to 0.5 mm.

[0166] In an embodiment, the width of the ribbon can be in the range of 5 mm to 213 mm. In an embodiment, the width of the ribbon can be in the range of 1 mm to 200 mm. In an embodiment, the width of the ribbon can be in the range of 10 mm to 250 mm. In an embodiment, the selected width of the ribbon can be based on the display size of the electronic device that utilizes the layered structure of the display thereon. For example, the width is selected such that it can have the size of the display of the electronic device or half of the size of the display of the electronic device or 1 / 3 of the size of the display of the electronic device or any desired width such that the display of the electronic device has structural integrity and high flexibility and is fully supported.

[0167] In an embodiment, the layer can include a silica-based glass sheet.

[0168] Figure 11 Shown according to an embodiment by Obtained characteristics of the silica glass. The Flex provides a thickness of less than 100 microns, a bending radius of less than 1 mm, and the ability to bend more than 300,000 times. Therefore, commercially available materials can be used to form these layers.

[0169] Several materials can be used for the substrate or backplane in the flexible display, including thin glass substrates such as Corning's Willow Glass from Corning Incorporated or They are specifically designed to be both flexible and rigid. Plastic materials such as polyethylene terephthalate (PET) and polyimide (PI) are also commonly used due to their flexibility and high temperature resistance. Thin metal foils (such as aluminum or copper) provide excellent rigidity while being lightweight. In some cases, organic materials or hybrid substrates combining different materials can be used, where the material selection depends on factors such as display size, shape, durability, and cost. The selection of substrate materials is an important consideration in the design and manufacture of flexible displays.

[0170] In an embodiment, the layers in the plurality of layers can be made of the same material or different materials. In an embodiment, for each layer, the layer can be made of similar thicknesses and different thicknesses. In an embodiment, each layer in the plurality of layers can be made of the same thickness and the same material. In an embodiment, each layer in the plurality of layers can be made of different thicknesses and different materials. In another embodiment, for a group of layers in the plurality of layers, the thickness and material can be the same.

[0171] In an embodiment, the top layer (on which the OLED is printed for display) can be composed of flexible silica glass and is firmly bonded to one or more layers of amorphous alloy or silica carrier along the flexible region.

[0172] Iron (Fe)-based amorphous ribbons and silica-based glass sheets can be used to form these layers. The produced Fe-based amorphous metal ribbons are commercially available in the market and can be selected for the support structure. Flexible silica glass (Gorilla ) sheets can also be used; and only outside the flexible display surface, as a flexible support structure.

[0173] Flexible Displays as an Integrated Display and Input Device

[0174] 1) A foldable display (FD) that can be connected to existing smartphones and other smart devices mainly serves as an input part and a display device. Figure 12 A roll-up / foldable screen is shown that can be used as an extension of the screen of an existing smartphone according to an embodiment.

[0175] The key advantage of using such a simple display / input device with existing smartphones and computers is that the FD utilizes existing devices. Most smartphones can immediately be used as flexible display devices at approximately 1 / 3 of the cost of purchasing a new smartphone with an FD.

[0176] Both foldable displays and roll-up displays can be connected to multiple central processing units (CPUs), smartphones or printers, audio-video devices, and TV remotes to be used as general input-output devices that connect us to our electronic world.

[0177] For example, a pen-sized roll-up display can be unfolded to a mini-pad-sized display and connected to home or office laptops, computers, mobile phones, vehicles, and automotive safety.

[0178] Medical staff can use high-definition displays to show patients MRI and other medical information. Figure 13 A roll-up / foldable screen is shown that can be used as an extension of an existing screen according to an embodiment.

[0179] A flexible display connected to a smartphone can conduct video conferencing as well as personal communication.

[0180] If the main display in a car is used for the GPS map function, the ability to control many other functions in the car simultaneously may be limited. Therefore, an FD can be allocated as the display for the GPS, leaving the main auto display for other functions.

[0181] 2) The use of an FD as a smartphone or laptop hardly needs explanation. However, even a fully independent smartphone with an FD can operate in an integrated manner to control and / or simply display information.

[0182] 3) Two or more flexible displays can be connected to form a single continuous screen.

[0183] The display can operate independently of the CPU via and can be charged using wireless charging. Figure 14 A roll-up / foldable screen according to an embodiment is shown that can be used as an extension and for applications in various situations.

[0184] A flexible display (i) can be connected to a mobile phone, (ii) can be used as a single unit for multiple screens, and (iii) can be used as a secondary display.

[0185] Figure 15 A cross-sectional view is shown that schematically shows the internal structure of a display device according to an exemplary embodiment. As Figure 15As shown, a display device 1500 according to an embodiment may include a housing 1510, a display panel 1520, an image processing board 1530, and a panel support member 1540 inserted between the display panel 1520 and the image processing board 1530. The housing 1510, the display panel 1520, and the image processing board 1530 are bendable by having a flexible structure. The panel support member 1540 is placed behind or below the display panel 1520 and supports the display panel 1520. When a user touches the upper surface of the display panel 1520 in front of or on the display panel 1520, the panel support member 1540 prevents the touched area of the display panel 1520 from being recessed in the -Z direction. In addition, the panel support member 1540 has a flexible structure such that the display device 1500 can be bent in the Z direction or the -Z direction. As described herein Figure 6 and Figure 7 provides a detailed panel support member 1540.

[0186] Figure 16 illustrates that a display panel touched in a display device according to an embodiment has a flexible structure. As Figure 16 shown, according to an embodiment, a display device 1600 is implemented by a mobile device, where a touch screen is applied to the display panel 1610. When a user touches the surface of the display panel 1610, an interaction with the display device 1600 is performed. In order for the display device 1600 to have a flexible structure according to the foregoing exemplary embodiments, the elements constituting the display device 1600 also need to have a flexible structure. If a user touches the display panel 1610 for an operation, the touched area 1611 is pressed and recessed inward, and the image in the corresponding area 1611 is distorted and deformed. To prevent this, a structure for supporting the back surface of the display panel 1610 is applied to the display device 1600.

[0187] According to an embodiment, it is a display including a flexible display device, where the flexible display device includes a plurality of layers, where each layer is connected to at least one other layer at a predetermined position to form a connection member, and where each layer of the plurality of layers includes a rotational degree of freedom and slides relative to an adjacent layer of the plurality of layers around the axis of folding or curling when the display is folded or curled.

[0188] According to an embodiment of the display, the display is operable as a secondary display of an electronic device. According to an embodiment of the display, the display is operable as an extension of an existing display for an electronic device. According to an embodiment of the display, the display is operable to be interconnected with a second display having a similar nature to form a continuous display.

[0189] According to an embodiment of the display, the display is operable to be connected via a wireless connection or a wired connection.

[0190] According to an embodiment of the display, the display is operable for wireless charging. According to an embodiment of the display, the display is a touch-sensitive display.

[0191] Amorphous alloy: An alloy can refer to a solid solution of two or more metallic elements (e.g., at least 2, 3, 4, 5 or more elements) or an intermetallic compound (including at least one metallic element and at least one non-metallic element). The term "element" herein can refer to an element that can be found in the periodic table. A metal can refer to any alkali metal, alkaline earth metal, transition metal, post-transition metal, lanthanide, actinide, and metalloid.

[0192] An amorphous alloy can refer to an alloy having an amorphous, amorphous atoms, or microstructure. An amorphous structure can refer to a glassy structure without observable long-range order; in some cases, the amorphous structure can exhibit some short-range order. Thus, an amorphous alloy can sometimes be referred to as a "metallic glass". Depending on the context, an amorphous alloy can refer to an alloy that is at least partially amorphous, including at least substantially amorphous alloys, such as fully amorphous alloys, etc. In an embodiment, an amorphous alloy can be an alloy in which at least about 50% (e.g., at least about 60%, about 70%, about 80%, about 90%, about 95%, about 99% or more) is an amorphous phase. The percentages herein can refer to volume percentages or weight percentages, depending on the context. The term "phase" herein can refer to physically distinct forms of a substance, such as a microstructure, etc. For example, a solid and a liquid are different phases. Similarly, an amorphous phase is different from a crystalline phase.

[0193] An amorphous alloy can contain multiple metallic elements and / or non-metallic elements. In some embodiments, an amorphous alloy can contain zirconium, titanium, iron, copper, nickel, gold, molybdenum, palladium, aluminum, or a combination thereof. In some embodiments, an amorphous alloy can be zirconium-based, titanium-based, iron-based, copper-based, nickel-based, gold-based, molybdenum-based, palladium-based, or aluminum-based. When referring to an alloy, the term "M-based" can refer to an alloy containing at least about 30% (e.g., about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, about 95%, or higher) of the M element. The percentages herein can refer to volume percentages or weight percentages, depending on the context.

[0194] The amorphous alloy can be a bulk-solidified amorphous alloy. A bulk-solidified amorphous alloy or a bulk amorphous alloy or a bulk metallic glass ("BMG") can refer to an amorphous alloy having dimensions at least in the millimeter range, which is generally thicker than a conventional amorphous alloy that typically has a thickness of 0.02 mm. In one embodiment, this dimension can refer to the minimum dimension. Depending on the geometry, the dimension can refer to thickness, height, length, width, radius, etc. In some embodiments, the minimum size can be at least about 0.5 mm - for example, about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 8 mm, about 10 mm, about 12 mm or greater. The size of the maximum dimension is not limited and can be in the millimeter range, centimeter range or even meter range.

[0195] Compared with the critical cooling rate of 105 K / second or higher for conventional amorphous alloys, the amorphous alloys (including bulk amorphous alloys) described herein can have a critical cooling rate of about 500 K / second or lower. The term "critical cooling rate" herein can refer to the cooling rate below which the amorphous structure is not energetically favorable and thus cannot be formed during the manufacturing process. In some embodiments, the critical cooling rate of the amorphous alloys described herein can be, for example, about 400 K / second or lower - such as about 300 K / second or lower, about 250 K / second or lower, about 200 K / second or lower. Some examples of bulk-solidified amorphous alloys can be found in U.S. Patent Nos. 5,288,344, 5,368,659, 5,618,359, and 5,735,975. In some embodiments where the required diameter (or width, thickness, etc., depending on the geometry) is smaller, a higher cooling rate can be used, such as the cooling rate used in conventional amorphous alloy manufacturing processes.

[0196] The amorphous alloy can have a variety of chemical compositions. In one embodiment, the amorphous alloy is a Zr-based alloy, such as a Zr-Ti-based alloy, such as (Zr,Ti) a (Ni,Cu,Fe) b (Be,Al,Si,B) c , where each of a, b, and c is independently a number representing atomic %, and a is in the range of 30 to 75, b is in the range of 5 to 60, and c is in the range of 0 to 50. There may also be other incidental and unavoidable trace impurities. In some embodiments, these alloys can accommodate a large amount of other transition metals, such as Nb, Cr, V, Co. In one embodiment, "a large amount" can refer to about 5 atomic % or more - for example, 10 atomic %, 20 atomic %, 30 atomic % or more.

[0197] In one embodiment, the amorphous alloy herein can have the chemical formula (Zr,Ti) b (Ni,Cu) b (Be) c , where each of a, b, and c is independently a number representing atomic percent, and a ranges from 40 to 75, b ranges from 5 to 50, and c ranges from 5 to 50. There may also be other incidental and unavoidable trace impurities. In another embodiment, the alloy can have the composition (Zr,Ti) b (Ni,Cu) b (Be) c , where a, b, and c are each independently a number representing atomic percent, and in atomic percentages, a ranges from 45 to 65, b ranges from 7.5 to 35, and c ranges from 10 to 37.5.

[0198] In another embodiment, the amorphous alloy described herein can have the chemical formula (Zr) a (Nb,Ti) b (Ni,Cu) c (Al) d , where each of a, b, c, and d is independently a number representing atomic percent and a ranges from 45 to 65, b ranges from 0 to 10, c ranges from 20 to 40, and d ranges from 7.5 to 15. There may also be other incidental and unavoidable trace impurities.

[0199] In some embodiments, the amorphous alloy can be an iron-based metallic alloy, e.g., an (Fe, Ni, Co)-based composition. Examples of such compositions are disclosed in U.S. Patent No. 6,325,868 and in the publications (A. Inoue et al., Appl. Phys. Lett., Vol. 71, p. 464 (1997)), (Shen et al., Mater. Trans., Jim, Vol. 42, p. 2136 (2001)), and Japanese Patent Application 2000126277 (Publication No. #2001303218A). For example, the alloy can be Fe 72 A l5 Ga2P 11 C6B4 or Fe 72 Al7Zr 10 Mo5W2B 15 .

[0200] Amorphous alloys (including bulk-solidified amorphous alloys) can have high strength and high hardness. Depending on the context, strength can refer to tensile or compressive strength. For example, Zr- and Ti-based amorphous alloys can have a tensile yield strength of about 250 ksi or higher, a hardness value of about 450 Vickers or higher, or both. In some embodiments, the tensile yield strength can be about 300 ksi or higher—for example, at least about 400 ksi, about 500 ksi, about 600 ksi, about 800 ksi, or higher. In some embodiments, the hardness value can be at least about 500 Vickers, for example, at least about 550, about 600, about 700, about 800, about 900 Vickers, or higher.

[0201] In one embodiment, a ferrous-metal-based amorphous alloy (including a ferrous-metal-based bulk-solidified amorphous alloy) can have a tensile yield strength of about 500 ksi or higher and a hardness value of about 1000 Vickers or higher. In some embodiments, the tensile yield strength can be about 550 ksi or higher—for example, at least about 600 ksi, about 700 ksi, about 800 ksi, about 900 ksi, or higher. In some embodiments, the hardness value can be at least about 1000 Vickers, for example, at least about 1100 Vickers, about 1200 Vickers, about 1400 Vickers, about 1500 Vickers, about 1600 Vickers, or higher.

[0202] Thus, any of the above amorphous alloys can have a desired strength-to-weight ratio. Additionally, amorphous alloys (particularly Zr-based or Ti-based alloys) can exhibit good corrosion resistance and environmental durability. Corrosion herein can refer to chemical corrosion, stress corrosion, or a combination thereof.

[0203] The amorphous alloys (including bulk amorphous alloys) described herein can have a high elastic strain limit of at least about 0.5% (including at least about 1%, about 1.2%, about 1.5%, about 1.6%, about 1.8%, about 2%, or higher)—a value much higher than that of any other metal alloy known to date. In an embodiment, at least one layer can comprise an amorphous alloy.

[0204] In some embodiments, the amorphous alloys (including bulk amorphous alloys) can additionally include some crystalline materials, such as crystalline alloys, etc. The crystalline materials can have the same or different chemical properties as the amorphous alloys. For example, in the case where the crystalline alloy and the amorphous alloy have the same chemical composition, they may differ only in microstructure.

[0205] In some embodiments, crystalline precipitates in an amorphous alloy may have an undesirable effect on the properties of the amorphous alloy, particularly on the toughness and strength of these alloys, and thus it is generally preferred to minimize the volume fraction of these precipitates. However, there may be cases where a ductile crystalline phase precipitates in-situ during the processing of the amorphous alloy, which can be beneficial to the properties of the amorphous alloy, particularly the toughness and ductility of the alloy. An exemplary case was disclosed by C.C. Hays et al. in Physical Review Letters, Volume 84, Page 2901 in 2000. In at least one embodiment herein, the crystalline precipitate may comprise a metal or an alloy, wherein the alloy may have the same composition as the amorphous alloy or a different composition from the amorphous alloy. Such amorphous alloys including these beneficial crystalline precipitates can be used in at least one embodiment described herein.

[0206] A particular advantage of bulk-solidified amorphous alloys is their stability in the supercooled liquid region, which in one embodiment is defined as the viscous liquid state above the glass transition temperature. The stability of this viscous liquid state can generally be measured by ΔT, which in one embodiment herein refers to the difference between the crystallization onset temperature Tx and the glass transition onset temperature Tg, as determined by standard differential scanning calorimetry ("DSC") measurements at a conventional heating rate (e.g., 20 °C). In some embodiments, the bulk-solidified amorphous alloy may have a ΔT of at least about 30 °C (e.g., at least about 50 °C, about 60 °C, about 70 °C, about 80 °C, about 90 °C, or higher).

[0207] According to an embodiment of the flexible display device, the amorphous material comprises an amorphous alloy having an elastic limit with at least 1.5% strain, and the amorphous alloy is selected from: (Zr,Ti) a (Ni,Cu,Fe) b (Be,Al,Si,B) c , where a = 30 - 75, b = 5 - 60, and c = 0 - 50 in atomic percentages; (Zr,Ti) a (Ni,Cu) b (Be) c , where a = 40 - 75, b = 5 - 50, and c = 5 - 50 in atomic percentages; (Zr,Ti) a (Ni,Cu) b (Be) c , where a = 40 - 65, b = 7.5 - 35, and c = 10 - 37.5 in atomic percentages; and (Zr) a (Nb,Ti) b (Ni,Cu) c (Al) d, where a = 45 - 65, b = 0 - 10, c = 20 - 40, and d = 7.5 - 15.

[0208] Although bulk-solidifying amorphous chemicals are considered, Fe-based tapes and silica-based sheets can be considered to form a spring structure in order to utilize multilayer thin amorphous sheets.

[0209] According to an embodiment of the flexible display device, the amorphous alloy includes an amorphous alloy of Zr-based, Ti-based, Zr-Ti-based, Fe-based, or a combination thereof.

[0210] According to an embodiment of the flexible display device, the amorphous alloy is at least substantially free of Be. According to an embodiment of the flexible display device, the amorphous alloy further includes a plurality of crystallization precipitates.

[0211] According to an embodiment of the flexible display device, at least one of the plurality of layers includes a plurality of structural components, the structural components including wires, strips, fibers, tapes, or a combination thereof, wherein the plurality of structural components are configured to provide structural stability and rigidity to maintain a flat shape of the display after the display is folded and opened or curled and unrolled multiple times. According to an embodiment of the flexible display device, the plurality of structural components include a series of horizontally aligned strips. According to an embodiment of the flexible display device, the plurality of structural components include a grid of horizontally and longitudinally aligned fibers. According to an embodiment of the flexible display device, at least one of the plurality of structural components includes (i) a fiber having a diameter between about 0.01 mm and about 0.5 mm or (ii) a tape having a thickness between about 0.023 mm and about 2 mm and a width of about 213 mm.

[0212] Amorphous tape: Amorphous tape (also known as metallic glass tape or metallic glass foil) is a unique material with an amorphous atomic structure. Amorphous tapes are typically thin and flat, with widths ranging from fractions of a millimeter (e.g., about 0.025 mm or 25 microns) to several millimeters. Their thickness can vary, but typically ranges from tens to hundreds of microns. The length of amorphous tapes can be quite long, usually wound on a spool or roll, and can be cut to any desired length. Amorphous tapes are typically made from alloys of various metal elements. Common elements for compositions used in metallic glass include transition metal elements such as iron (Fe), nickel (Ni), and cobalt (Co), which are typically used as the main components, and metalloid elements such as boron (B) and silicon (Si) are added to the alloy to disrupt the formation of crystal structures and promote the amorphous state, and may include small amounts of other elements such as phosphorus (P), carbon (C), or chromium (Cr) to fine-tune the properties of the alloy.

[0213] The specific composition of the amorphous strip can vary depending on the desired properties and intended applications. The amorphous strip is produced by a rapid solidification process called melt spinning, in which the molten metal is rapidly quenched on a rotating cooling wheel, preventing the formation of a crystal structure. This rapid cooling results in the amorphous atomic arrangement characteristic of metallic glasses. The thin and flat shape of the strip makes them advantageous for applications where a combination of unique properties such as high strength, magnetic properties, or corrosion resistance is required.

[0214] Foldable Display Structure (FDS): Aspects of the embodiments described herein provide a foldable display structure (“FDS”) that includes an amorphous alloy and a method of manufacturing a near-net shape foldable display structure from the amorphous alloy. At least in part due to the amorphous alloy, the FDS described herein can have properties that are both achievable and significantly superior to pre-existing display structures. The surprising advantages of foldable display structures that incorporate amorphous alloys (particularly bulk-solidifying amorphous alloys) will be described in the following different embodiments.

[0215] One embodiment provides an FDS that includes an amorphous alloy that provides form and shape durability in combination with high flexibility, high resistance to chemical and environmental effects, and low-cost near-net shape manufacturing for complex designs and shapes. Another embodiment provides a method of manufacturing a foldable display structure in near-net shape from such an amorphous alloy. The amorphous alloy can be a bulk-solidifying amorphous alloy.

[0216] In one embodiment, a structure is provided that includes a display and at least one structural component disposed on a portion of the display. The display can include at least one organic material, including OLEDs. In one embodiment, the display does not need to include an organic material. Generally, any flexible display material can be used. The display or a portion thereof can be foldable. In some embodiments, the entire structure is foldable. In one embodiment, the structure can be or can include a foldable display and optional structural components. In one embodiment, the structure includes a display and at least one structural component.

[0217] At least one structural component can include at least one amorphous alloy. In one embodiment, at least one structural component consists essentially of an amorphous alloy. In another embodiment, at least one structural component includes an amorphous alloy. The amorphous alloy can be any of the above amorphous alloys having any of the above properties. In one embodiment, the amorphous alloy can be a bulk-solidifying amorphous alloy.

[0218] In one embodiment, the combination of high strength and high strength-to-weight ratio of the bulk-solidified amorphous alloy can significantly reduce the total weight and bulkiness of the foldable display structure, thereby allowing the thickness of these display structures to be reduced while maintaining structural integrity and high flexibility. Additionally, as described above, the amorphous alloy including the bulk-solidified amorphous alloy has a high elastic strain limit. This property is important for the use and application of the foldable display structure; specifically, the high elastic strain limit can allow the display structure to be thin and highly flexible. Additionally, the high elastic strain limit can also allow the foldable display structures described herein to withstand loads and / or flexure without permanent deformation or failure, and enable them to be folded (and curled) into a compact shape for multiple use and opening and closing. The term "fold" herein may include "curl" to refer to compressing the material. At least in part due to the high elasticity, the foldable displays described herein can remain at least substantially flat, such as completely flat, after the structural components are folded and opened multiple times. In one embodiment, the foldable display can remain at least substantially at the same flatness level as before the first fold after being folded and opened multiple times.

[0219] Furthermore, at least in part due to the amorphous alloy, the foldable display structures described herein can exhibit corrosion resistance (e.g., chemical corrosion, stress corrosion, etc.) and high inertness. The high corrosion resistance and inertness of the amorphous alloy in the structural components can be used to prevent the foldable display structure from degrading due to environmental effects. Finally, in combination with the high strength, high hardness, high elasticity, and corrosion-resistant properties, the above properties can provide a foldable display structure that is durable and resistant to wear and scratches during normal use.

[0220] The foldable display structure including the display and the structural components described herein can have any geometry, including size or shape. The structure can have a symmetric shape or an asymmetric shape. In a plan view, the foldable display structure can be square, rectangular, circular, oval, polygonal, or irregular in shape. Compared to a frame or a housing, the structural components in many of the embodiments described herein do not cover the entire surface of the display. The structural components can also have various geometries at least partially according to the geometry of the foldable display. For example, the structural components can include lines, strips, fibers, tapes, or combinations thereof. These lines, strips, fibers, tapes, etc. can be arranged parallel (or almost parallel) to each other above (or directly on) the display, or they can cross each other to form a grid. In one embodiment, the foldable portion of the display corresponds to the portion of the display on which (or directly on which) at least one structural component is arranged. The structural components can be joined to the display by any technique. In one embodiment, the structural components are joined to the display by a polymer such as epoxy glue or any other material that can bond the structural components to the display.

[0221] The display structures described herein can have multiple layers. In one embodiment, a structural component including an amorphous alloy can be disposed over a substrate layer, which in turn can be disposed over a display. The structural component can be sandwiched between the display and the substrate or can be over the substrate (or directly over the substrate) that is over the display (or directly over the display).

[0222] The structural component can have any suitable size, depending on the application. Figure 17 A schematic view of an exemplary foldable display structure including a display 1701 and a structural component including a series of horizontally aligned strips 1702 is shown, the series of horizontally aligned strips 1702 including an amorphous alloy (e.g., amorphous alloy strips or tapes). As described herein Figure 6 and Figure 7 A structure including multiple layers is provided for each of the horizontally aligned strips 1702. These strips can have a thickness between about 1 μm and 2.0 mm - for example, between about 0.001 mm and about 1.5 mm, between about 0.2 mm and about 1.0 mm, between about 0.4 mm and about 0.8 mm, between about 0.5 mm and about 0.6 mm. Other ranges are possible. These strips can have a width between about 0.5 and about 250.0 mm - for example, between about 0.5 mm and about 15 mm, between about 2.0 mm and about 10 mm, between about 4.0 mm and about 8.0 mm, between about 5.0 mm and about 6.0 mm. Other ranges are possible. The length of the strips can vary at least in part depending on the geometry of the display on which (or directly on which) the structural component is disposed. These strips can extend to the edge of the display or extend further outward from the edge of the display. In this embodiment, the display can be folded (including being curled) in a segmented manner, where the strips provide a certain rigidity along the display. In a preferred embodiment, the strips are bonded to an OLED display using various bonding methods such as using epoxy glue lights.

[0223] Figure 18 A schematic view of an exemplary foldable display structure including a display 1801 and a structural component including a grid of horizontally and longitudinally aligned fibers 1803 is shown, the fibers 1803 including an amorphous alloy (e.g., amorphous alloy strips or tapes). As described herein Figure 6 and Figure 7A structure is provided that includes multiple layers for each of the strips 1801, 1803 for horizontal alignment and vertical alignment. The fibers can have a diameter between about 0.01 mm and 2.0 mm - for example, between about 0.02 mm and about 1.5 mm, between about 0.03 mm and about 1.0 mm, between about 0.05 mm and about 0.5 mm, between about 0.1 mm and about 0.4 mm, between about 0.2 mm and about 0.3 mm. Other ranges are also possible. The mesh network can extend to the edge of the display or can further extend outside the edge of the display. In this embodiment, the display can be folded in a continuous manner, where the fiber mesh provides flexibility for curling and provides rigidity and flatness when the display is opened. In one embodiment, the fiber mesh is bonded to the display using various bonding methods (such as using epoxy glue, etc.).

[0224] Figure 19 (a) shows a schematic diagram of an exemplary foldable display structure that includes a display 1901 and a structural component that includes a set of longitudinally aligned strips 1904, and the set of longitudinally aligned strips 1904 includes an amorphous alloy (e.g., a bulk-solidified amorphous alloy or an amorphous strip). As described herein Figure 6 and Figure 7 A structure is provided that includes multiple layers for each of the strips 1904 for longitudinal alignment. The strips can have a thickness between about 1 μm and 2.0 mm (e.g., between about 0.02 mm and about 1.5 mm, between about 0.03 mm and about 1.0 mm, between about 0.05 mm and about 0.5 mm, between about 0.1 mm and about 0.4 mm, between about 0.2 mm and about 0.3 mm). The strips can have a width between about 0.5 mm and about 20.0 mm (e.g., between about 1.0 mm and about 15 mm, between about 2.0 mm and about 10 mm, between about 4.0 mm and about 8.0 mm, between about 5.0 mm and about 6.0 mm). The strips can extend to the edge of the display or can further extend outward from the edge of the display. In this embodiment, the display can be folded in a continuous manner, where the strips can provide flexibility for curling and provide rigidity and flatness when the display is opened. In one embodiment, the strip mesh is bonded to the display using various joining methods (such as using epoxy glue, etc.).

[0225] In some embodiments described herein, the terms "strip" and "fiber" refer to highly flexible components, each of which can be folded (as Figure 19a diameter in the range of about 10 mm to about 100 mm (e.g., about 20 mm to about 80 mm, about 40 mm to about 60 mm) as shown at 1902 in (b), while the terms "ribbon" and "line" refer to relatively rigid components, each of which can be folded into a diameter greater than 30 mm (e.g., greater than 40 mm, 50 mm, 60 mm or more).

[0226] At least in part due to the desired properties described above, the FDSs described herein can be used as components of various devices including electronic devices. The electronic devices herein can refer to mobile phones, smart phones, PDAs, computers (e.g., laptop computers, desktop computers, tablet computers, etc.), televisions, and different wall-mounted displays. The devices can contain multiple FDSs described herein. In one embodiment, multiple FDSs can be combined together to form a large display. For example, small-sized (e.g., smaller than a pre-existing personal reader or tablet computer) FDSs can be used as secondary displays outside of a device (e.g., a smart phone). In an embodiment where the FDS is part of a smart phone, one FDS can be used to perform a navigation function, while another FDS is used to read emails, and at the same time the smart phone can be used for calls - which can also be done with one data plan. In another embodiment, at home or in the office, a "connected" device can be used to drive multiple FDSs simultaneously, sequentially, or both, some as televisions, some as computers, and some as communication devices. In at least one embodiment, compared to pre-existing glass-based displays such as LCDs (liquid crystal displays), the display structures described herein are more desirable due to their extremely light weight, flexibility, and less susceptibility to breakage.

[0227] Manufacturing method: Another aspect of the embodiments described herein provides a method of manufacturing a foldable display structure, such as a foldable display structure in a near-net shape, the foldable display structure including a display that includes an organic material and at least one structural component including at least one amorphous alloy. The display and the structural component can be any of those described above.

[0228] An embodiment provides a method of fabricating a foldable display structure, the method comprising: providing a feedstock of an amorphous alloy, the amorphous alloy feedstock being substantially amorphous and having an elastic strain limit of about 1.5% or greater and a ΔT of 30 °C or greater; heating the feedstock to near the glass transition temperature; shaping the heated feedstock into a desired near-net shape of the foldable display structure; and cooling the formed component to a temperature well below the glass transition temperature. As described above, ΔT refers to the difference between the crystallization onset temperature Tx and the glass transition onset temperature Tg. In one embodiment, the temperature near the glass transition refers to a temperature that can be below, at, or near the glass transition and above the glass transition temperature, but always at a temperature below the crystallization temperature Tx. The cooling step can be carried out at a rate similar to the heating rate of the heating step. Alternatively, it can be carried out at a rate greater than the heating rate of the heating step. The cooling step can also be achieved while maintaining the shaping and forming.

[0229] An embodiment provides a method of fabricating a foldable display structure, the method comprising: providing a homogeneous alloy ingot (not necessarily fully or partially amorphous); heating the feedstock to a casting temperature above the melting temperature; introducing the molten alloy into a mold cavity having a near-net shaped foldable display structure, and quenching the molten alloy to a temperature below the glass transition.

[0230] One embodiment provides a method of fabricating a foldable display structure, the method comprising assembling the display with at least one structural component. The assembly can involve disposing and / or attaching at least one structural component on a portion of the display. As described above, the attachment can involve gluing the display and at least one structural component (e.g., using an epoxy adhesive) together. An advantage of the methods described herein is that the assembly of the components of the foldable display structure can involve little (or no) use of fasteners.

[0231] In one embodiment where the display structure provided herein has a substrate and a display, the structural component can be disposed above (or directly on) the substrate during the production of the substrate. The substrate can comprise any material, including those used in pre-existing displays, such as plastics, glass, etc. Since the amorphous alloy (of the structural component) can withstand higher temperatures than most plastic and synthetic substrate materials, a synthetic material can be poured over the structural component to form a tight bond. The bond can be chemical, physical, or both. A tight bond can refer to a bond having a very small observable gap between the bonded components, and in some cases, as a result, the components may not be easily separable. Alternatively, one or more structural components can be provided between two adhesive substrate materials such that all of these can be bonded.

[0232] At least one structural component can be made by a method that includes heating a feedstock comprising at least substantially an amorphous alloy to a first temperature greater than or equal to the glass transition temperature (Tg) of the alloy; forming the heated feedstock into a preform; and cooling the preform to a second temperature below Tg to form at least one structural component.

[0233] The feedstock can include an alloy that is at least partially (such as at least substantially, such as completely) amorphous. The method can further include a method of making the alloy feedstock. The method of making the alloy feedstock can include heating at least one ingot comprising an alloy that is not at least partially amorphous to a third temperature greater than or equal to the melting temperature (Tm) of the alloy; and cooling the heated ingot at a rate sufficient to form a feedstock comprising at least substantially an amorphous alloy. The ingot can include a mixture of elements to be alloyed to form the feedstock. The ingot can be homogeneous (although it need not be) with respect to the chemical composition of the elements of the alloy mixture, but can be non - amorphous. The cooling rate during making the feedstock can be fast enough to bypass the crystallization - formation region in the time - temperature - transformation (TTT) diagram to avoid forming a crystalline phase, thereby forming at least partially an amorphous feedstock.

[0234] In one embodiment, during the process of making a foldable display structure, the heated feedstock is formed into a preform before cooling the preform to form the final structural components of the display structure. Forming can include, for example, shaping the preform into a desired shape. The process can involve any technique known in the art. For example, this can involve casting, which involves introducing the feedstock into a cavity of a mold to form the preform. In some embodiments, forming can involve shaping the feedstock into a preform using pressure. The pressure can be mechanical pressure, such as by hand, tool, or pneumatic pressure. The preform can be a near - net shape of the structural component. In other words, no (or minimal) additional machining is required to shape the preform into the desired shape of the structural component. In some embodiments, certain post - treatments, such as certain surface treatments, can be employed. For example, a surface treatment can be used to remove oxides from the surface. Chemical etching (with or without a mask) as well as polishing and buffing operations can also be employed to improve the surface finish.

[0235] The near-net shape of the structural components of the illustrated structure during the process described herein is a distinguishing feature compared to pre-existing processes. Specifically, the preferred materials of existing processes using shape memory Ti-Ni alloys and / or spring steels can be produced only in very limited shapes and forms (such as wires and flat strips, etc.) because it is difficult to produce near-net shaped products. In contrast, the near-net shaping ability of the amorphous alloys (especially bulk-solidified amorphous alloys) of the processes described herein allows for the fabrication of complex foldable display structures with high precision and reduced process steps. Additionally, this can also allow for minimal use of bending and welding, which can degrade structural performance and increase manufacturing cost and aesthetic defects. In one embodiment, manufacturing the foldable display structure in a near-net shaped form can significantly reduce manufacturing cost while still forming a foldable display structure with complex features (such as precision curves, etc.) and a high surface finish on aesthetically sensitive areas. Moreover, without being bound by any particular theory, but (bulk-solidified) amorphous alloys retain their fluidity from above the melting temperature down to the glass transition temperature due to the lack of a first-order phase change. This is distinguishable from conventional crystalline metals and alloys or even certain amorphous alloys in some cases. Since the amorphous alloys retain their fluidity, they do not accumulate significant stresses as they cool from their casting temperature down below the glass transition temperature. Thus, dimensional distortions from thermal stress gradients can be minimized.

[0236] Exemplary embodiments: In one embodiment, the foldable display structure includes at least one component made of a bulk-solidified amorphous alloy or an amorphous alloy strip.

[0237] In another embodiment, the foldable display structure includes longitudinally aligned strips or fibers made substantially of a bulk-solidified amorphous alloy or an amorphous strip and attached to the back (substrate side) of the OLED display.

[0238] In another embodiment, the foldable display structure includes horizontally aligned strips or fibers made substantially of a bulk-solidified amorphous alloy or an amorphous strip and attached to the back of the OLED display.

[0239] In yet another embodiment, the foldable display structure includes a grid of strips or fibers made substantially of a bulk-solidified amorphous alloy or an amorphous strip and attached to the back of the OLED display.

[0240] In yet another embodiment, the foldable display structure includes a set of strips or fibers made substantially of a bulk-solidified amorphous alloy or an amorphous strip and connected to the back of the OLED display.

[0241] In yet another embodiment, the foldable display structure includes diagonally crossing and rigid strips or lines made of a bulk metallic glass or amorphous ribbon and attached to the back of the OLED display.

[0242] In one embodiment, the foldable display structure is at least partially made of a Zr-Ti based bulk metallic glass or amorphous ribbon.

[0243] In another embodiment, the bulk metallic glass or amorphous ribbon in the foldable display structure is Be-free.

[0244] In another embodiment, the foldable display structure is at least partially made of a Zr / Ti based bulk metallic glass or amorphous ribbon having in-situ ductile crystalline precipitates.

[0245] In another embodiment, a molten sheet of the bulk metallic glass or amorphous ribbon is cast into a near-net-shape fabricated foldable display structure.

[0246] In another embodiment, a feedstock of the bulk metallic glass or amorphous ribbon is molded into a near-net-shape fabricated foldable display structure.

[0247] In another embodiment, at least a portion of a near-net-shape fabricated foldable display structure is formed by casting or molding a bulk metallic glass.

[0248] In another embodiment, the near-net-shape fabricated foldable display structure is a near-net-shape molded part.

[0249] In another embodiment, the near-net-shape fabricated foldable display structure is a near-net-shape cast part.

[0250] An embodiment provides a method of fabricating a near-net-shape fabricated foldable display structure, the method including the steps of: providing a molten alloy feedstock above Tm; introducing the molten alloy into a mold cavity having a near-net-shape foldable display structure; quenching and removing the part from the mold cavity; and final finishing.

[0251] Another embodiment provides a method of fabricating a near-net-shape fabricated foldable display structure, the method including the steps of: providing an at least partially amorphous alloy feedstock; heating the feedstock above Tg but below Tx, shaping the heated feedstock into a desired near-net-shape foldable display structure; cooling; and final finishing.

[0252] Another embodiment provides a foldable display structure including a bulk metallic glass or amorphous ribbon.

[0253] Another embodiment provides a method of manufacturing a foldable display structure in a near-net shape, including a bulk-solidified amorphous alloy or an amorphous strip.

[0254] Another embodiment provides a foldable display structure having a structure substantially made of a bulk-solidified amorphous alloy or an amorphous strip, wherein structural components are fixed without using fasteners.

[0255] According to an embodiment, it is a manufacturing method, including: selecting a number of layers to form a plurality of layers based on a predetermined thickness of a flexible display device; selecting a thickness of each of the plurality of layers; selecting a material for each layer such that an elastic limit of the material is at least 1.5% strain; positioning the layers in a desired configuration; and firmly connecting the layers such that each layer is connected to at least one other layer at a predetermined position to form a connection member; and wherein the flexible display device is part of a display of an electronic device; and wherein each of the plurality of layers includes a degree of rotational freedom and slides relative to an adjacent layer among the plurality of layers about an axis of folding or curling when the display is folded or curled.

[0256] According to an embodiment of the manufacturing method, the connection member is a rigid connection point. According to an embodiment of the manufacturing method, the connection member includes a mechanical connection member, which includes one of spot welding, fastening connection members, and rivets. According to an embodiment of the manufacturing method, the connection member includes a mechanical connection member, and the mechanical connection member includes a telescopic sliding connection member.

[0257] U.S. Patent Publication No. US11183651B2, titled "Electronic apparatus", the entire content of which is incorporated herein by reference, attempts to provide an electronic device having improved reliability against stress caused by bending. The electronic device EA includes a first component MB1, a second component MB2, a third component MB3, a first adhesive component AM1, and a second adhesive component AM2.

[0258] U.S. Patent Publication No. US9029846B2, entitled "Display apparatus having improved bending properties and method of manufacturing same" (the entire content of which is incorporated herein by reference), attempts a display apparatus having improved bending properties. The disclosed display apparatus includes: a display module including a flexible substrate, a display panel, and a encapsulation film; a lower module disposed below the display module; an upper module disposed on the display module; and an elastic adjustment layer including an adhesive material, the elastic adjustment layer being disposed on or below the display module to adjust the position of the neutral plane in the bending of the display apparatus, wherein the elastic modulus of the elastic adjustment layer is less than the elastic modulus of at least one of the display module, the lower module, or the upper module so as to position the neutral plane within or near the display module.

[0259] In the above prior art, attempts have been made to reduce the bending stress by having an adhesive layer between the foldable display layers. Having an adhesive layer between the layers bonds the layers together and still moves them together as a single solid piece when a force is applied. Except for the support structures explained in this disclosure, the electronic devices and controls, and the housing for the display screen are similar in nature and operation to the prior art patents.

[0260] The description of one or more embodiments is for illustrative purposes and not intended to be exhaustive or limiting of the embodiments described herein. Many modifications and variations will be apparent to a person of ordinary skill in the art without departing from the scope and spirit of the embodiments described. The terms used herein are best used to explain the principles of the embodiments, practical applications, and / or technical improvements over the technology found in the marketplace, and / or to enable a person of ordinary skill in the art to understand the embodiments described herein.

[0261] Introduced for reference

[0262] All references mentioned herein (including issued patents and patent application publications) are incorporated herein by reference in their entirety.

[0263] U.S. Patent Publication No. US10035184B2, entitled "Material for eyewear and eyewear structure".

[0264] U.S. Patent Publication No. US10280493B2, entitled "Foldable display structures".

[0265] U.S. Patent Publication No. US10301708B2, entitled "Foldable display structures".

[0266] U.S. Patent Publication No. US10697049B2, entitled "(Foldable display structures)".

[0267] U.S. Patent Publication No. US9710020B2, entitled "Rollable display apparatus".

[0268] U.S. Patent Publication No. US10459489B2, entitled "Display panel and display apparatus including the same".

[0269] U.S. Patent Publication No. US10133381B2, entitled "Display apparatus".

[0270] U.S. Patent Publication No. US11183651B2, entitled "Electronic apparatus".

[0271] U.S. Patent Publication No. US9029846B2, entitled "Display apparatus having improved bending properties and method of manufacturing same".

Claims

1. A flexible display device includes a plurality of layers, wherein, Each layer is connected to at least one other layer at a predetermined position, thereby forming a connecting member, wherein the flexible display device is part of a display of an electronic device, and wherein each of the plurality of layers includes a degree of freedom of rotation, and when the display is folded or curled, each of the plurality of layers slides relative to an adjacent layer of the plurality of layers about an axis of folding or curling.

2. The flexible display device according to claim 1, wherein, Each of the plurality of layers includes a material having an elastic strain limit of at least 1.5%.

3. The flexible display device according to claim 1, wherein, A flexible silica glass surface forms a first surface layer facing the display side and is supported by a second surface layer having an amorphous sheet.

4. The flexible display device according to claim 3, wherein, The amorphous sheet includes silica or an alloy.

5. The flexible display device according to claim 3, wherein, An organic light-emitting diode (OLED) is printed on the flexible silica glass surface.

6. The flexible display device according to claim 3, wherein, The flexible silica glass surface is firmly bonded to one or more layers of amorphous alloy along a flexible region.

7. The flexible display device according to claim 3, wherein The flexible silica glass surface is firmly bonded to one or more layers of silica along a flexible region.

8. The flexible display device according to claim 1, wherein, At least one of the plurality of layers includes an amorphous material.

9. The flexible display device according to claim 8, wherein, The amorphous material includes an iron-based amorphous strip.

10. The flexible display device according to claim 8, wherein, The amorphous material includes a silica-based glass sheet.

11. The flexible display device according to claim 1, wherein, The plurality of layers of the flexible display device form a spring structure.

12. The flexible display device according to claim 9, wherein, The iron-based amorphous strip includes 84%-100% of iron in a first range, 0-10% of silicon in a second range, 0-5% of boron in a third range, and 0-2% of manganese in a fourth range.

13. The flexible display device according to claim 9, wherein, The iron-based amorphous strip includes 0-100% of iron in a first range, 0-85% of cobalt in a second range, 0-50% of nickel in a third range, 0-10% of silicon in a fourth range, 0-8% of molybdenum in a fifth range, 0-5% of boron in a sixth range, and 0-2% of manganese in a seventh range.

14. The flexible display device according to claim 8, wherein, The amorphous material includes an amorphous alloy having an elastic strain limit of at least 1.5%, and the amorphous alloy is selected from: (Zr,Ti) a (Ni,Cu,Fe) b (Be,Al,Si,B) c , where a = 30 - 75, b = 5 - 60, and c = 0 - 50 in atomic percentage; (Zr,Ti) a (Ni,Cu) b (Be) c , where a = 40 - 75, b = 5 - 50, and c = 5 - 50 in atomic percentage; (Zr,Ti) a (Ni,Cu) b (Be) c , where a = 40 - 65, b = 7.5 - 35, and c = 10 - 37.5 in atomic percentage; and (Zr) a (Nb,Ti) b (Ni,Cu) c (Al) d , where a = 45 - 65, b = 0 - 10, c = 20 - 40, and d = 7.5 - 15.

15. The flexible display device according to claim 14, wherein, The amorphous alloy includes an amorphous alloy of Zr-based, Ti-based, Zr-Ti-based, Fe-based or a combination thereof.

16. The flexible display device according to claim 14, wherein, The amorphous alloy is at least substantially free of Be.

17. The flexible display device according to claim 14, wherein, The amorphous alloy further includes a plurality of crystalline precipitates.

18. The flexible display device according to claim 1, wherein, At least one of the plurality of layers includes a plurality of structural components, the plurality of structural components including wires, strips, fibers, tapes or a combination thereof, wherein the plurality of structural components are configured to provide structural stability and rigidity to maintain a flat shape of the display after the display is folded and opened or curled and unfolded multiple times.

19. The flexible display device according to claim 18, wherein, The plurality of structural components include a series of horizontally aligned strips.

20. The flexible display device according to claim 18, wherein The plurality of structural components include a grid of horizontally aligned and longitudinally aligned fibers.

21. The flexible display device according to claim 18, wherein, At least one of the plurality of structural components includes: (i) a fiber having a diameter between about 0.01 mm and about 0.5 mm, or (ii) a tape having a thickness between about 0.023 mm and about 2 mm and a width of about 213 mm.

22. The flexible display device according to claim 1, wherein, The connecting member is a rigid connecting member, wherein the rigid connecting member includes a mechanical connecting member, and the mechanical connecting member includes one of spot welding, fastening connecting members, rivets and telescopic sliding connecting members.

23. The flexible display device according to claim 1, wherein, Each of the plurality of layers has a thickness in the range of 0.01 mm to 0.1 mm.

24. The flexible display device according to claim 1, wherein, The combined thickness of the plurality of layers is in the range of 0.01 mm to 5.0 mm.

25. The flexible display device according to claim 1, wherein, The predetermined position is configured such that changing the predetermined position changes the degree of free sliding.

26. The flexible display device according to claim 1, wherein, The display includes at least one organic light-emitting diode; wherein at least one of the plurality of layers includes at least one amorphous alloy; and wherein the display remains at least substantially flat after being folded and opened a plurality of times.

27. The flexible display device according to claim 1, wherein The flexible display device is part of one or more of a mobile phone, a smartphone, a personal digital assistant, a computer, a television, a wall-mounted display.

28. The flexible display device according to claim 1, wherein Each of the plurality of layers has a different thickness.

29. The flexible display device according to claim 1, wherein Each of the plurality of layers has the same thickness.

30. The flexible display device according to claim 1, wherein, The first layer closer to the display side among the plurality of layers has a first thickness different from the second thickness of the second layer farther from the display side among the plurality of layers, wherein the first thickness is less than the second thickness, and wherein the elastic strain limits of the first material of the first layer and the second material of the second layer are at least 1.5%.

31. The flexible display device according to claim 1, wherein, A lubricating mechanism is positioned between adjacent layers, and the lubricating mechanism is configured to reduce friction and facilitate free movement of the layers relative to each other.

32. The flexible display device according to claim 31, wherein, The lubricating mechanism includes a dry lubricant.

33. The flexible display device according to claim 31, wherein, The lubricating mechanism includes a liquid lubricant that is accommodated in a sealed channel between adjacent layers.

34. The flexible display device according to claim 1, wherein, A magnetic field is used to hold the plurality of layers in a stable position until sufficient force is applied to release the layers.

35. A display including a flexible display device, wherein, The flexible display device includes a plurality of layers, wherein each layer is connected to at least one other layer at a predetermined position, thereby forming a connection member, and wherein each of the plurality of layers includes a degree of rotational freedom, and when the display is folded or curled, each of the plurality of layers slides relative to an adjacent layer among the plurality of layers about the axis of folding or curling.

36. The display according to claim 35, wherein, The display is operable as a secondary display of an electronic device.

37. The display according to claim 35, wherein, The display is operable as an extension of an existing display for an electronic device.

38. The display according to claim 35, wherein, The display is operable to be connected via a wireless connection or a wired connection.

39. The display according to claim 35, wherein, The display is operable to interconnect with a second display having similar properties to form a continuous display.

40. The display according to claim 35, wherein, The display is operable for wireless charging.

41. The display according to claim 35, wherein, The display is a touch-sensitive display.

42. A manufacturing method, comprising: selecting the number of layers to form a plurality of layers based on a predetermined thickness of a flexible display device; selecting the thickness of each of the plurality of layers; selecting a material for each layer such that the elastic strain limit of the material is at least 1.5%; positioning the layers in a desired configuration; and firmly connecting the layers such that each layer is connected to at least one other layer at a predetermined position, thereby forming a connection member; and wherein the flexible display device is part of a display of an electronic device; and wherein each of the plurality of layers includes a degree of rotational freedom, and when the display is folded or curled, each of the plurality of layers slides relative to an adjacent layer among the plurality of layers about the axis of folding or curling.

43. The manufacturing method according to claim 42, wherein, The connection member is a rigid connection member.

44. The manufacturing method according to claim 42, wherein, The connection member includes a mechanical connection member, and the mechanical connection member includes one of spot welding, a fastening connection member, and a rivet.

45. The manufacturing method according to claim 42, wherein, The connecting member includes a mechanical connecting member, and the mechanical connecting member includes a telescopic sliding connecting member.

Images