Electronic device with folded display with flexible zone support structure

Abstract

A foldable display may have a display cover layer that is curved about a bending axis and a display panel. The display panel may have an array of pixels configured to display an image through the display overlay. The display cover layer may be formed from a glass layer. A recess may be formed in the glass layer that extends along and overlaps the bending axis. The recess forms a flexible locally thinned portion in the glass that allows the display cover layer to bend. A polymer may be formed in the recess. A hardened structure, such as a glass strip and a glass bead having one or more diameters, may be embedded in the polymer to help resist inward compression of the surface of the display overlay in the locally thinned area while allowing the display overlay to bend about the bending axis.

Description

Electronic devices with foldable displays featuring flexible support structures

[0001] This application is a divisional application of the invention patent application with application number 202180084611.7, application date December 8, 2021, entitled "Electronic device with foldable display having flexible area support structure".

[0002] This application claims priority to U.S. Patent Application No. 17 / 538,701, filed November 30, 2021; U.S. Provisional Patent Application No. 63 / 127,690, filed December 18, 2020; and U.S. Provisional Patent Application No. 63 / 166,555, filed March 26, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates in general to electronic devices, and more specifically to electronic devices having a display. Background Technology

[0004] Electronic devices typically have a display. Portability may be a concern for some devices, which often limits the available space for the display. Summary of the Invention

[0005] An electronic device may have a foldable housing that allows the device to fold and unfold about a bending axis. A flexible display may be mounted within the foldable housing. The flexible display may have a pixel array forming a display panel. The display panel may be configured to bend along the bending axis when the device is folded.

[0006] The flexible display may have a display cover layer that overlaps with the display panel. The display cover layer may be formed of a glass layer. A groove-shaped recess may be formed in the glass layer, extending parallel to a bending axis. This recess forms a flexible, locally thinned portion in the glass above the bending axis, allowing the display to bend around the bending axis.

[0007] Polymers can be placed in recesses to help flatten the inner surface of the display cover. Hardened structures such as glass strips and / or glass beads with one or more diameters can be embedded in the polymer to help harden the surface of the display cover in locally thinned areas, so that the outer surface of the display cover is not too easily deformed by external pressure from objects such as styluses. When supporting the outer surface of the display cover, the hardened structures allow the display cover to bend satisfactorily about a bending axis. Attached Figure Description

[0008] Figure 1 is a schematic diagram of an exemplary electronic device according to the implementation scheme.

[0009] Figure 2 is a perspective view of an exemplary electronic device with a display according to an embodiment.

[0010] Figure 3 is a cross-sectional side view of an exemplary electronic device according to the implementation scheme.

[0011] Figure 4 is a cross-sectional side view of an exemplary display with a cover layer having a hinge region with local thinning, according to an embodiment.

[0012] Figure 5 is a cross-sectional side view of an exemplary partially thinned display overlay with an outer coating and an inner coating according to an embodiment.

[0013] Figure 6 is a cross-sectional side view of an exemplary partially thinned display overlay with an inner coating, which is formed as an integral part of the recess filling layer according to an embodiment.

[0014] Figure 7 is a cross-sectional side view of an exemplary locally thinned display cover with a polymer filler containing embedded particles, according to an embodiment.

[0015] Figure 8 is a graph showing the average particle size in the layer according to the distance through which the polymer layer is filled in the exemplary recess, based on the embodiment.

[0016] Figure 9 is a cross-sectional side view of an exemplary display cover with a locally thinned portion according to the embodiment.

[0017] Figures 10 and 11 are cross-sectional side views of an exemplary display overlay with a locally thinned region according to an embodiment, the locally thinned region having a polymer with an embedded hardened member.

[0018] Figure 12 is a cross-sectional side view of an exemplary hardening member for increasing compressive rigidity to a locally thinned portion of the cover layer, according to an embodiment. Detailed Implementation

[0019] Electronic devices may be equipped with a display. The display can be used to show images to a user. The display may be formed from an array of light-emitting diode pixels or other pixels. For example, the device may have an organic light-emitting diode display or a display formed from an array of micro light-emitting diodes (e.g., diodes formed from crystalline semiconductor dies).

[0020] Figure 1 illustrates a schematic diagram of an exemplary electronic device with a display. Device 10 may be a cellular phone, tablet computer, laptop computer, wristwatch or other wearable device, television, stand-alone computer monitor or other monitor, computer monitor with an embedded computer (e.g., desktop computer), system embedded in a vehicle, multimedia terminal or other embedded electronic device, media player or other electronic equipment. Configurations where device 10 is a cellular phone, tablet computer or other portable electronic device may sometimes be described herein as examples. This is exemplary. In general, device 10 may be any suitable electronic device with a display.

[0021] Device 10 may include control circuitry 20. Control circuitry 20 may include storage and processing circuitry for supporting the operation of device 10. This storage and processing circuitry may include storage devices such as non-volatile memory (e.g., flash memory or other electrically programmable read-only memory configured to form a solid-state drive), volatile memory (e.g., static or dynamic random access memory), etc. The processing circuitry in control circuitry 20 may be used to acquire input from sensors and other input devices, and may be used to control output devices. The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors and other wireless communication circuits, power management units, audio chips, application-specific integrated circuits, etc. During operation, control circuitry 20 may use displays and other output devices to provide visual output and other outputs to the user.

[0022] To support communication between device 10 and external equipment, control circuitry 20 may communicate using communication circuitry 22. Circuitry 22 may include an antenna, radio frequency transceiver circuitry (wireless transceiver circuitry), and other wireless communication circuitry and / or wired communication circuitry. Circuitry 22, sometimes referred to as control circuitry and / or control and communication circuitry, may support bidirectional wireless communication between device 10 and external equipment via a wireless link (e.g., circuitry 22 may include radio frequency transceiver circuitry, such as a wireless LAN transceiver circuitry configured to support communication via a wireless LAN link, a near-field communication transceiver circuitry configured to support communication via a near-field communication link, a cellular transceiver circuitry configured to support communication via a cellular telephone link, or a transceiver circuitry configured to support communication via any other suitable wired or wireless communication link). For example, this could be achieved via Bluetooth. ® Link, WiFi ®Wireless links, including wireless links operating at frequencies between 6 GHz and 300 GHz, 60 GHz links or other millimeter-wave links, cellular phone links, wireless LAN links, personal area network communication links, or other wireless communication links, support wireless communication. Device 10 may, if desired, include power circuitry for transmitting and / or receiving wired and / or wireless power, and may include a battery or other energy storage device. For example, device 10 may include coils and rectifiers to receive wireless power supplied to the circuitry in device 10.

[0023] Device 10 may include input-output devices such as device 24. Input-output device 24 may be used to acquire user input, to acquire information about the user's surrounding environment, and / or to provide output to the user. Device 24 may include one or more displays, such as display 14. Display 14 may be an organic light-emitting diode display, a liquid crystal display, an electrophoretic display, an electrowetting display, a plasma display, a microelectromechanical system (MEMS) display, a display having a pixel array formed of crystalline semiconductor light-emitting diode dies (sometimes referred to as microLEDs), and / or other displays. Configurations in which display 14 is an organic light-emitting diode display or a microLED display are sometimes described herein as examples.

[0024] Display 14 may have an array of pixels configured to display images to a user. The pixels may be formed as part of a flexible display panel. This allows device 10 to fold and unfold about a bending axis. For example, the flexible (bendable) display in device 10 can be folded so that device 10 can be placed in a compact shape for storage and unfolded when it is desired to view an image on the display.

[0025] The sensor 16 in the input-output device 24 may include force sensors (e.g., strain gauges, capacitive force sensors, resistive force sensors, etc.), audio sensors (such as microphones), touch and / or proximity sensors (such as capacitive sensors, e.g., two-dimensional capacitive touch sensors integrated into the display 14, two-dimensional capacitive touch sensors overlapping the display 14 and / or touch sensors forming buttons, touchpads or other input devices not associated with the display), and other sensors. If desired, sensor 16 may include optical sensors (such as optical sensors that emit and detect light), ultrasonic sensors, optical touch sensors, optical proximity sensors and / or other touch and / or proximity sensors, monochrome and color ambient light sensors, image sensors, fingerprint sensors, temperature sensors, sensors for measuring three-dimensional non-contact posture (“aerial posture”), pressure sensors, sensors for detecting position, orientation, and / or motion (e.g., accelerometers, magnetic sensors such as compass sensors, gyroscopes, and / or inertial measurement units containing some or all of these sensors), health sensors, radio frequency sensors, depth sensors (e.g., structured light sensors and / or depth sensors based on stereo imaging devices that capture three-dimensional images), optical sensors such as self-mixing sensors and light-detection and ranging (LiDAR) sensors that collect time-of-flight measurements, humidity sensors, moisture sensors, eye-tracking sensors, and / or other sensors. In some arrangements, device 10 may use sensor 16 and / or other input-output devices to acquire user input. For example, buttons can be used to capture button press input, touch sensors that overlap with the display can be used to capture user touchscreen input, touchpads can be used to capture touch input, microphones can be used to capture audio input, accelerometers can be used to monitor when a finger touches the input surface and therefore can be used to capture finger press input, etc.

[0026] If necessary, electronic device 10 may include additional components (see, for example, other devices 18 in input-output device 24). Additional components may include tactile output devices, audio output devices such as speakers, light-emitting diodes for status indicators, light sources such as light-emitting diodes illuminating portions of the housing and / or display structure, other optical output devices, and / or other circuitry for collecting input and / or providing output. Device 10 may also include batteries or other energy storage devices, wired communication for supporting auxiliary equipment, connector ports for receiving wired power, and other circuitry.

[0027] Figure 2 is a perspective view of an electronic device 10 in an exemplary configuration, where device 10 is a portable electronic device, such as a cellular phone or tablet computer. As shown in Figure 2, device 10 may have a display, such as display 14. Display 14 may cover part or all of the front of device 10. Touch sensor circuitry, such as two-dimensional capacitive touch sensor circuitry, may be integrated into display 14.

[0028] Display 14 may be mounted in housing 12. Housing 12 may form the front and rear housing walls, side wall structures, and / or internal support structures (e.g., frames, optional intermediate plate members, etc.) of device 10. Glass structures, transparent polymer structures, and / or other transparent structures covering other portions of display 14 and device 10 may provide structural support for device 10 and may sometimes be referred to as housing structures. For example, a transparent housing portion such as a glass or polymer housing structure that covers and protects the pixel array in display 14 may act as a display overlay for the pixel array and also as a housing wall on the front of device 10. In configurations where the display overlay is formed of glass, the display overlay may sometimes be referred to as a display cover glass or display cover glass layer. Portions of housing 12 on the side and rear walls of device 10 may be formed of glass or other transparent and / or opaque structures. The side and rear wall structures may be formed as extensions to the front portion of housing 12 (e.g., as an integral part of the display overlay) and / or may include separate housing wall structures.

[0029] The housing 12 may have a flexible structure (e.g., a bendable housing wall structure) and / or a hinge structure, such as hinge 30. Hinge 30 may have a hinge axis aligned with the bending axis 28 of the device. The hinge 30 and / or the flexible housing structure overlapping the bending axis 28 may allow the housing 12 to bend about the bending axis 28. For example, the housing 12 may have a first portion located on one side of the bending axis 28 and a second portion located on the opposite side of the bending axis 28, and these two housing portions may be connected by hinge 30 for rotational movement about axis 28.

[0030] When the housing 12 bends about the bending axis 28, the flexibility of the display 14 allows the display 14 to bend about the axis 28. In an exemplary configuration, the housing 12 and the display 14 can bend 180°. This allows the display 14 to fold backward on itself (where the first outward-facing portion and the second outward-facing portion of the display 14 face each other). The ability to position the device 10 in a folded configuration in this way helps to make the device 10 compact, allowing the device 10 to be stored efficiently. When it is desired to view an image on the display 14, the device 10 can unfold about the axis 28 to position the device 10 in the unfolded configuration of FIG. 2. This allows the display 14 to lie flat and allows the user to view a flat image on the display 14. The ability to fold the display 14 back onto itself allows the device 10 to exhibit inward-folding behavior. The display 14 can be flexible enough to allow the device 10 to fold outward and / or inward.

[0031] The device 10 of Figure 2 has a rectangular outline (rectangular perimeter) with four corners. As shown in Figure 2, the first pair of parallel edges (e.g., the left and right edges of device 10 in the example of Figure 2) may be longer than the second pair of parallel edges (e.g., the upper and lower edges of device 10 in Figure 2), which are oriented at right angles to the first pair of parallel edges. In this type of configuration, the housing 12 extends along a longitudinal axis perpendicular to the bending axis 28. If desired, the housing 12 may have other shapes (e.g., a shape in which the housing 12 has a longitudinal axis extending parallel to the bending axis 28). Using the type of arrangement shown in Figure 2, the length of device 10 along its longitudinal axis can be reduced by folding device 10 around axis 28.

[0032] Figure 3 is a cross-sectional side view of an exemplary foldable electronic device. Device 10 of Figure 3 can be bent about a bending axis 28. The bending axis 28 can be aligned with the display overlay 14CG or other structures in device 10. For example, the bending axis 28 can pass through a portion of the display overlay 14CG, or it can be located above or below the layer 14CG.

[0033] As shown in Figure 3, the display 14 includes a pixel P array of a display panel 14P formed under the inward-facing surface of the display cover layer 14CG. The display panel 14P can be, for example, a flexible organic light-emitting diode display or a micro-LED display, wherein the light-emitting pixels are formed on a flexible substrate layer (e.g., a flexible layer of polyimide or a sheet of other flexible polymers). The flexible support layer for the display 14 can also be formed of flexible glass, flexible metal and / or other flexible structures.

[0034] The display overlay 14CG may be formed of a polymer, glass, a crystalline material such as sapphire, other materials, and / or combinations of these materials. To enhance flexibility, a portion of layer 14CG that overlaps with and extends along the bending axis 28 may be locally thinned (e.g., this portion may be thinner relative to a portion of layer 14CG that does not overlap with the bending axis 28). The thickness of layer 14CG (e.g., the non-thinned portion of layer 14CG) may be 50 to 200 micrometers, 70 to 150 micrometers, 100 to 200 micrometers, 100 to 600 micrometers, at least 100 micrometers, at least 200 micrometers, less than 600 micrometers, less than 400 micrometers, less than 250 micrometers, less than 150 micrometers, less than 100 micrometers, at least 50 micrometers, or other suitable thicknesses.

[0035] In the example of Figure 3, housing 12 has a portion on its rear R that forms a rear housing wall and has side portions that form side walls 12W. The rear housing wall of housing 12 may form a support layer for components in device 10. Housing 12 may also have one or more internal support layers (e.g., frame structures, such as optional intermediate plates, etc.). These internal support layers and the rear housing wall may have first and second portions that are coupled to opposite sides of a hinge aligned with bending axis 28 (see, for example, hinge 30 in Figure 2) or may be flexible enough to bend about bending axis 28.

[0036] Electronic components 32 may be installed inside the device 10 (e.g., between the display 14 and the rear of the housing 12). Component 32 may include circuitry of the type shown in FIG. 1 (e.g., control circuitry 20, communication circuitry 22, input-output devices 24, battery, etc.). The display 14 may be mounted on the front surface F of the device 10. When the device 10 is folded about axis 28, the display cover 14CG, the display panel 14P, and other structures of the device 10 that overlap with the bending axis 28 may flex and bend to accommodate the folding.

[0037] The outer and / or inner surfaces of the display cover layer 14GC may be coated. These coatings may include, for example, anti-reflective coatings, scratch-resistant coatings, anti-fouling coatings, and / or other coatings. As an example, consider a cross-sectional side view of the display cover layer 14CG of FIG. 4. As shown in FIG. 4, the display cover layer may have an outer surface (facing the outer surface) such as surface 40 and an opposite inner surface (facing the inner surface) such as surface 42. A strip-shaped region of the display cover layer 14CG that overlaps with and extends parallel to the bending axis 28 may be locally thinned (e.g., a groove or other recess extending parallel to the bending axis 28 may be formed in the layer 14CG to form a locally thinned portion 44 of the layer 14CG). The locally thinned portion 44 of the layer 14CG may be thinner than other portions of the layer 14CG, such as non-thinned portions 46 (which may be, for example, a planar glass layer portion of the layer 14CG). The presence of portion 44 in the display cover layer 14CG facilitates bending of the display cover layer 14CG around the bending axis 28.

[0038] To help flush the inner surface 42 and thus facilitate (e.g., using an adhesive layer) mounting of the display panel 14P against the inner surface 42, an elongated recess (groove) forming a thinned portion 44 in the inner surface of the layer 14CG can be filled with polymer 50. Polymer 50 can be sufficiently flexible to bend about a bending axis 28 when the device 10 is opened and closed. The refractive index of polymer 50 can be matched with the refractive index of the display overlay layer 14CG to help minimize light reflection (e.g., by incorporating inorganic nanoparticles into polymer 50). For example, at a wavelength of 500 nm, the refractive index of polymer 50 can differ from the refractive index of layer 14CG by less than 0.15, less than 0.1, or less than 0.05 (as an example).

[0039] Coating 52 may be formed on the outer surface 40. Coating 52 may include, for example, a scratch-resistant layer (sometimes referred to as a hard coating), a protective polymer layer, an antifog layer, an anti-fog layer, an anti-reflective layer, an antistatic layer, an adhesive layer, and / or other coatings. In some configurations, each of these functions may be achieved using a separate, appropriate coating. In other configurations, a single layer may provide multiple functions. Generally, coatings such as coating 52 may be formed on the outer surface 40 and / or the inner surface 42. In the exemplary configuration of FIG. 4, coating 52 is formed on the outer surface 40.

[0040] Coating 52 can be provided in any suitable order. As an example, the bottommost coating of coating 52 (e.g., a coating formed directly on surface 40 of FIG. 4) can be a hard coating or another scratch-resistant layer that helps prevent scratches that may damage layer 14CG. An anti-reflective coating can be formed on top of the scratch-resistant layer. The anti-reflective layer can be a thin-film interference filter anti-reflective coating comprising a stack of thin-film layers, such as dielectric sublayers with alternating refractive indices. One of the thin-film layers can be a conductive layer used as an antistatic layer, such as a transparent semiconductor layer (e.g., an indium tin oxide layer). An anti-fogging or anti-hazing coating can be formed on top of the anti-reflective layer. An anti-fogging coating (e.g., a hydrophobic polymer coating) helps reduce fingerprints and other undesirable marks on the surface of display 14. An example of an anti-fogging coating is a fluoropolymer coating (e.g., a fluoropolymer formed from evaporated perfluoropolyether) used as an oleophobic layer. An intermediary adhesive layer can be used to adhere the fluoropolymer to the underlying coating.

[0041] As shown in Figure 5, the recessed portion forming the locally thinned portion 44 in the display cover layer 14CG may have a tapered cross-sectional shape. For example, as shown in Figure 5, the top portion of the recess may be characterized by a width W1 that is narrower than the width W2 of the lower portion of the recess. This type of arrangement helps avoid abrupt transitions in the thickness of the cover glass and thus helps reduce stress concentration while visually concealing the presence of the recess. To help protect the display cover layer 14CG (e.g., to avoid processing-induced defects), one or more coatings may be formed on the inner surface 42. For example, as shown in Figure 5, a protective coating 54 (e.g., a polymer layer) may be formed on the inner surface 42. Layer 54 may have any suitable thickness (e.g., at least 0.05 micrometers, at least 0.1 micrometers, at least 0.4 micrometers, at least 2 micrometers, at least 5 micrometers, less than 50 micrometers, less than 20 micrometers, less than 7 micrometers, less than 3 micrometers, or other suitable thicknesses). If desired, a protective polymer layer, such as layer 54, may be formed on the outer surface 40 (for example, one of the layers 52 in FIG4 may be a protective polymer layer such as layer 54).

[0042] The protective layer 54 can be formed on the inner surface 42 by depositing polymer 50 and layer 54 separately (either using the same polymer material for both polymer 50 and layer 54 or using different polymers for polymer 50 and layer 54). As an example, polymer 50 can be deposited in the recess forming the thinned portion 44 and cured before the protective polymer layer is deposited and cured on polymer 50 and the non-thinned area of ​​the inner surface 42.

[0043] In another exemplary arrangement, the protective layer on the inner surface 42 may be formed as an integral part of the polymer in the recesses of the filling layer 14CG. As shown in FIG6, for example, the same polymer (polymer 50) may be used to fill the recesses under the thinned portion 44 and to form a protective coating (polymer 50') on the surface 42. In this type of arrangement, polymers 50 and 50' may be deposited by applying a liquid polymer material to the inner surface 42, followed by the application of heat, light (e.g., ultraviolet light) and / or a catalyst to promote polymer curing.

[0044] During use of device 10, a computer stylus, fingertip, or other external object may press against the outer surface 40 of display cover 14CG (e.g., to supply touch input to a touch sensor located between the opposing inner surfaces of display panel 14P and display cover 14CG, or to supply touch input to a touch sensor formed as part of display panel 14P). The thinned portion 44 of display cover 14CG is preferably flexible enough to allow display cover 14CG to bend about bending axis 28. Simultaneously, it may be desirable to prevent the area of ​​surface 40 overlapping with bending axis 28 from being pressed inward too easily, as this could create undesirable detectable differences in the hardness of outer surface 40 when an external object moves across bending axis 28. To help prevent excessive inward compression of surface 40 in the area of ​​display cover 14CG overlapping with thinned portion 44, a hardened structure separate from display cover 14CG may be incorporated into polymer 50 in a recess beneath thinned portion 44. These hardened structures may be granules or elongated members (e.g., elongated strips, rods, etc.). The material forming the hardened structure can be glass, polymer, ceramic, crystalline material such as sapphire, and / or other rigid materials (e.g., one or more materials having a higher elastic modulus than polymer 50, and therefore being harder). By incorporating a structure more rigid than polymer 50 into polymer 50, the stiffness of the thinned portions of layer 14CG can be locally enhanced (e.g., resistance to localized inward compression) while still allowing display 14 to bend freely about axis 28.

[0045] As an example, consider the arrangement in Figure 7. As shown in Figure 7, a hardening structure such as hardening particles 60 can be incorporated into the polymer 50 within a recess beneath the thinned portion 44 of the display overlay layer 14CG. Particles 60 can be spherical or other shaped particles and can be formed of a material such as glass with an elastic modulus greater than that of the polymer 50 (e.g., particles 60 can be glass beads). This hardens the polymer 50 and helps prevent the portion of surface 40 above the thinned portion 44 from being too easily pressed down (e.g., too easily deformed inwards locally) by pressure from the tip of a stylus or other external object on surface 40. Simultaneously, because the particles 60 are not directly connected to each other by any rigid structure (e.g., because a portion of polymer 50 exists between adjacent particles), the particles 60 move freely relative to each other when the polymer 50 flexes. Therefore, layer 14CG and polymer 50 can still be freely bent about bending axis 28.

[0046] Particle 60 can be any suitable size. As an example, the diameter of the particle (e.g., average diameter) can be at least 0.1 micrometer, at least 0.2 micrometer, at least 0.3 micrometer, at least 0.5 micrometer, at least 1 micrometer, at least 2 micrometer, at least 5 micrometer, at least 25 micrometer, 0.2 micrometer to 10 micrometer, 1 micrometer to 20 micrometer, 1 micrometer to 50 micrometer, 0.5 micrometer to 50 micrometer, less than 100 micrometer, less than 50 micrometer, less than 25 micrometer, less than 12 micrometer, less than 6 micrometer, or less than 2.5 micrometer (as an example).

[0047] To help match the refractive index of polymer 50 with that of display overlay 14CG, in addition to including optional hardening structures such as hardened particles 60 or other hardening structures, it is also desirable to include refractive index matching particles 62 in polymer 50. As an example, the refractive index matching particles 62 may be formed from particles of inorganic dielectrics (e.g., silicon dioxide, metal oxides such as zirconium oxide particles, alumina particles, titanium dioxide particles, etc.). Such refractive index matching particles may have a nanoscale size and are sometimes referred to as refractive index matching nanoparticles. As an example, the refractive index matching particles 62 may have a subwavelength size (e.g., diameters of about 10 nm, 1 nm to 100 nm, at least 2 nm, less than 300 nm, less than 250 nm, less than 200 nm, less than 150 nm, less than 100 nm, less than 50 nm, less than 40 nm, 1 nm to 50 nm, 2 nm to 40 nm, etc.). The concentration of the refractive index matching particles 62 may be increased to increase the effective refractive index of polymer 50 and may be decreased to decrease the effective refractive index of polymer 50. In this way, the refractive index of polymer 50 can be matched with the refractive index of display cover layer 14CG and with the refractive index of particles 60 or other hardened structures (e.g., to reduce reflections at the contact surfaces between polymer 50 and these structures).

[0048] The diameter of particle 60 may be uniform, or particle 60 may comprise spheres or other particles of different sizes. If desired, the diameter of particle 60 (e.g., average diameter) may be constant throughout polymer 50. In arrangements where the size of particle 60 varies, the diameter of particle 60 may vary depending on its position within polymer 50. As an example, the diameter of particle 60 (e.g., average diameter) may decrease or otherwise vary depending on a distance d from surface 40. Generally, any one or more properties of particle 60 may vary with distance d. As shown in the graph of Figure 8, one or more properties of particle 60, such as property M, may vary continuously (see, for example, the smooth and continuously decreasing curve 64 of Figure 8) and / or may vary gradually (see, for example, the gradually decreasing curve 66 of Figure 8). Property M may be any suitable particle property, such as particle diameter, particle material, particle refractive index, particle shape, particle concentration in polymer 50 (e.g., number of particles per unit volume), and / or other particle properties.

[0049] In an arrangement where the diameter of the particles 60 decreases with increasing distance from the surface 42 at the top of the recess in the cover layer 14CG of the polymer 50 (and therefore with increasing distance from the outer surface 40), larger particles that contribute to hardening of the surface 40 will be present near the top of the recess (e.g., closer to the outer surface 40), and smaller particles will be present near the bottom of the recess (e.g., closer to the rear of layer 14CG). The presence of smaller particles near the bottom of the recess helps to make the lower portion of the polymer 50 more flexible than the upper portion of the polymer 50. Because the bottom portion of polymer 50 tends to stretch more than the upper portion of polymer 50 when the display cover 14CG is bent about the bending axis 28 (e.g., when the two halves of display 14 are folded toward themselves), the use of graded particle sizes (e.g., a curing scheme in which the average diameter of particle 60 decreases with increasing distance d) helps to provide the desired amount of surface curing to the area of ​​surface 40 that overlaps with polymer 50, while maintaining the desired flexibility in the display cover 14CG, allowing device 10 and display 14 to be folded. Any suitable technique can be used to form polymer 50 with embedded curing structures such as particles 60 with a size gradient. Using an illustrative configuration, a mixture of liquid polymer material containing particles 60 of varying sizes is used to cover the thinned region 44, while the display cover 14CG rests with its inner surface facing upwards. In this type of configuration, gravity will tend to separate the particles by size, after which the polymer material can be cured.

[0050] As described in conjunction with curve 66 in Figure 8, the characteristic M of particle 60 can exhibit a gradual change with distance d. This type of arrangement is shown in a cross-sectional side view of the display overlay 14CG in Figure 9. In the example of Figure 9, a first polymer layer 50-1 containing particles 60 of a first diameter is used, followed by a second polymer layer 50-2 containing particles 60 of a second diameter smaller than the first diameter (at a greater distance d from the surface 40) to form polymer 50. In this example, polymer 50 is deposited in two layers (e.g., a first layer as a liquid deposition and curing and a second layer as a liquid deposition on the cured first layer and subsequently cured). A configuration with three or more discrete layers, each discrete layer containing particles 60 of a different size, can also be used.

[0051] If desired, elongated members formed of glass or other hardened materials can be incorporated into the polymer 50 within the locally thinned region 44. As shown in Figure 10, for example, a series of parallel elongated members, such as glass strips 70 or other members extending parallel to the bending axis 28, can serve as a hardening structure. Strips 70 can be incorporated into the polymer 50 to help vertically harden the surface 40 within the locally thinned portion 44 of the display cover layer 14CG (e.g., to help prevent the surface 40 from deforming inward too easily when the portion of surface 40 overlapping the thinned portion 44 is contacted by a computer stylus or other external object pressing inward on the surface 40). Although strips 70 provide enhanced vertical rigidity to surface 40 above portion 44, the presence of strips 70 will not reduce the flexibility of the display 14 relative to bending around the bending axis 28, because strips 70 move freely relative to each other and relative to the thinned portion 44 of the display cover layer 14CG when the display 14 is folded.

[0052] The polymer 50 filling the recess of the thinned portion 44 of the display cover layer 14CG may extend laterally to cover an area of ​​the inner surface 42 on the non-thinned portion of the display cover layer 14CG (see, for example, portion 50', as described in conjunction with FIG. 6). If desired, a separate polymer protective coating may be formed on the inner surface 42 (see, for example, coating 54 of FIG. 5). As described in conjunction with layer 52 of FIG. 4, one or more optional layers, such as layer 52 of FIG. 10, may be provided on the outer surface 40. Any suitable number of parallel strips 70 may be present in the recess of the thinned portion 44. In the example of FIG. 10, three strips 70 are present. If desired, fewer or more than three strips 70 may be present. The strips 70 may be formed of glass or other rigid transparent materials (transparent ceramic, sapphire, or other crystalline materials, etc.). Configurations in which the strips 70 are glass strips and are placed parallel to surfaces 40 and 42 when the display 14 is in an unfolded planar state are sometimes described herein as examples. The presence of strip 70 helps ensure that surface 40 does not deform inward too easily when touched by a stylus or other external object. The presence of elongated polymer-filled gaps between adjacent strips 70 (e.g., gaps extending parallel to the bending axis 28) helps ensure that display 14 exhibits sufficient flexibility to bend around axis 28 when device 10 is folded and unfolded.

[0053] In the example of Figure 11, a display cover layer similar to the display cover layer of Figure 10 has been constructed using a pair of laminated layers. In the locally thinned portion 44, the display cover layer 14CG exhibits enhanced local flexibility because only a single thickness of display cover layer material (e.g., a single glass layer) is present (e.g., display cover layer 14CG-1 is present in portion 44, but display cover layer 14CG-2 is absent). In portion 46, the display cover layer 14CG comprises both an upper display cover layer 14CG-1 and a lower display cover layer 14CG-2 (e.g., an additional glass layer). The lower display cover layer 14CG-2 is attached to the upper display cover layer 14CG-1 by a polymer layer (e.g., a portion of polymer 50 or a separate polymer layer) such as polymer adhesive 72. Polymer 50 may have a portion 50' extending to form a protective inner surface cover layer on surface 42, or a separate protective polymer layer may be formed on surface 42, as shown in Figure 5. The layer 14CG-2 of Figure 11 has two halves (e.g., a left and right half separated by a gap forming a recess in the display cover layer 14CG beneath the thinned portion 44). The gap in layer 14CG-2 helps enhance the flexibility of layer 14CG, allowing layer 14CG to bend about the bending axis 28. Strips 70 and / or other hardened structures may be embedded in the polymer 50 formed in the gap between the left and right halves of layer 14CG.

[0054] To help reduce cracks that could weaken strip 70, strip 70 may be etched in a glass etchant (e.g., HF) and / or mechanically polished. This process and / or other processing techniques may be used to form glass strips such as strip 70 of Figure 12, which have a rectangular shape with rounded corners 70R in their cross-sectional profile. The presence of rounded corners 70R or other curved surface profiles helps prevent chipping and other damage when adjacent strips 70 come into contact with each other, and helps remove cracks that could lead to crushing.

[0055] The thickness of the display overlay 14CG in region 44 can be 30 micrometers to 200 micrometers, at least 10 micrometers, at least 20 micrometers, less than 500 micrometers, less than 300 micrometers, less than 200 micrometers, less than 100 micrometers, or other suitable thicknesses less than the thickness of the display overlay 14CG in the non-thinning region. The thickness of the glass strip 70 (which can be the same as the thickness of layer 14CG-2 in the configuration of FIG. 11) can be 30 micrometers to 200 micrometers, at least 10 micrometers, at least 20 micrometers, less than 500 micrometers, less than 300 micrometers, less than 200 micrometers, less than 100 micrometers, or other suitable thicknesses. The thickness of the display overlay 14CG in region 46 can be 30 micrometers to 600 micrometers, 100 micrometers to 600 micrometers, 100 micrometers to 400 micrometers, at least 30 micrometers, at least 100 micrometers, at least 200 micrometers, less than 3000 micrometers, less than 1000 micrometers, less than 600 micrometers, less than 400 micrometers, or other suitable thicknesses.

[0056] Strips 70 may each have the same width, or the widths of strips 70 may differ from one another. The width of each strip 70 may be at least 10 micrometers, at least 100 micrometers, at least 500 micrometers, at least 1.5 mm, at least 3 mm, at least 6 mm, 1 mm to 10 mm, 1 mm to 3 mm, 0.5 mm to 2 mm, less than 10 mm, less than 7 mm, less than 4 mm, less than 2.5 mm, less than 1.5 mm, or other suitable width. The length of each strip 70 may span the entire width of device 10 (e.g., each strip 70 may have a length equal to the distance of the bending axis 28 across device 10 and display 14), or each strip of strip 70 may be divided along its length into two or more segments (e.g., a strip may have two or more segments arranged end-to-end with a common width spanning display 14). Strips 70 may be formed of the same material as display cover layer 14CG (e.g., the same glass), or may be formed of a material having the same or similar refractive index. This helps to match the refractive index value of strip 70 with the refractive index of display overlay 14CG (for example, such that the refractive index of strip 70 differs from the refractive index of layer 14CG and from the refractive index of polymer 50 by less than 0.15, less than 0.1, or less than 0.05, as an example).

[0057] To help enhance the rigidity of surface 40 above thinned portion 44, polymer 50 of Figures 10 and 11 may include glass beads or other hardened particles in addition to hardened structures such as strip 70 (e.g., the polymer-filled groove under portion 44 may contain both hardened structures such as glass beads and hardened structures such as glass strips). The hardened particles may be particles such as particle 60 of Figure 7. Such particles may have a single diameter or may have a varying diameter (e.g., a varying diameter as shown by curves 64 and 66 of Figure 8, or otherwise a diameter that decreases as the distance from the outer surface 40 into polymer 50 increases). If desired, refractive index matching nanoparticles 62 may also be incorporated into polymer 50 to help match the refractive index of polymer 50 with that of strip 70 and display overlay 14CG (e.g., thinned portion 44).

[0058] Polymer 50 may be hardened and / or matched to the refractive index of display overlay 14CG using a non-uniform mixture or a homogeneous mixture of embedded particles (particles of different sizes, shapes, and / or materials). The embedded particles (e.g., particles 60 and / or 62 and / or other particles in polymer 50) may be formed from materials having a refractive index different from that of polymer 50 (e.g., particles used to match the refractive index of polymer 50 to overlay 14CG and optionally harden polymer 50) and / or from materials having a matching refractive index (e.g., particles used to harden polymer 50 but not to change the refractive index of polymer 50). The embedded particles may be nanoparticles and / or larger particles having fixed properties throughout polymer 50 and / or having one or more properties that vary depending on the distance through the thickness of polymer 50.

[0059] The embedded particles may, for example, have an average size or other properties (e.g., composition, shape, etc.) that vary in a smooth and continuous (non-gradual) manner and / or in a gradual manner according to their position within the polymer 50 (e.g., according to distance d). The embedded particles may be formed from glass beads, other glass particles, and / or other dielectrics (e.g., beads or other particles formed from silica, metal oxides such as zirconium oxide particles, alumina particles, titanium dioxide particles, etc.). The embedded particles may be spherical, plate-shaped (e.g., sheet-like), rod-shaped, and / or may have other suitable shapes.

[0060] In an exemplary configuration, the embedded particles are characterized by their average diameter. The average diameter of the particles can be 0.01 μm to 50 μm, 0.05 μm to 25 μm, 0.01 μm to 25 μm, 0.03 μm to 50 μm, at least 0.01 μm, at least 0.1 μm, at least 1 μm, less than 50 μm, less than 5 μm, less than 0.5 μm, etc. The average diameter can be fixed throughout the homogeneous mixture in the polymer 50 and / or can have values ​​within these ranges or other suitable ranges that vary depending on the location within the polymer 50 (e.g., according to distance d). As an example, the dielectric particles embedded in the polymer 50 can be characterized by an average diameter of 0.01 μm to 50 μm (or other suitable range), which is fixed throughout the polymer 50 or varies depending on the distance through the polymer 50 (e.g., distance d), while simultaneously enhancing the resistance of the outer surface of the display cover layer 14CG to inward deformation over locally thinned portions of the display cover layer and simultaneously allowing the display cover layer to bend about the bending axis 28.

[0061] As described above, one aspect of this technology involves collecting and using information, such as information from input-output devices. This disclosure envisions, in some cases, the collection of data including personal information that uniquely identifies or can be used to contact or locate specific individuals. Such personal information data may include demographic data, location-based data, telephone numbers, email addresses, Twitter IDs, home addresses, data or records related to a user's health or fitness level (e.g., vital sign measurements, medication information, exercise information), date of birth, usernames, passwords, biometric information, or any other identifying information or personal information.

[0062] This disclosure recognizes that the use of such personal information within the technology disclosed herein can be used to benefit users. For example, the personal information data can be used to deliver targeted content that is of interest to the user. Therefore, the use of such personal information data enables users to have planned control over the content delivered. Furthermore, this disclosure also anticipates other uses of personal information data that are beneficial to users. For example, health and fitness data can be used to provide insights into a user's overall health status or as positive feedback for individuals using technology to pursue health goals.

[0063] This disclosure assumes that entities responsible for collecting, analyzing, disclosing, transmitting, storing, or otherwise using such personal information data will comply with established privacy policies and / or privacy practices. Specifically, such entities should implement and adhere to privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy and security of personal information data. Such policies should be easily accessible to users and should be updated as data collection and / or use change. Personal information from users should be collected for the entity's lawful and reasonable purposes and not shared or sold outside of these lawful uses. Furthermore, such collection / sharing should be conducted only after obtaining informed consent from users. Additionally, such entities should consider taking any necessary steps to protect and safeguard access to such personal information data and ensure that others with access to such personal information data comply with their privacy policies and processes. Furthermore, such entities may be subject to third-party evaluations to demonstrate their compliance with widely accepted privacy policies and practices. Additionally, policies and practices should be adapted to the specific types of personal information data collected and / or accessed, and to applicable laws and standards, including specific considerations regarding jurisdiction. For example, in the United States, the collection or access to certain health data may be governed by federal and / or state laws such as the Health Insurance and Accountability Act (HIPAA), while in other countries health data may be subject to other regulations and policies and should be processed accordingly. Therefore, different privacy practices should be maintained for different types of personal data in each country.

[0064] Regardless of the foregoing, this disclosure also anticipates implementation schemes for users to selectively block the use or access to personal information data. That is, this disclosure anticipates providing hardware and / or software components to prevent or block access to such personal information data. For example, the technology may be configured to allow users to opt-in or opt-out at any time during or after registering for the service. Alternatively, users may choose not to provide specific types of user data. Furthermore, users may choose to limit the length of time user-specific data is retained. In addition to providing opt-in and opt-out options, this disclosure also envisions providing notifications related to access to or use of personal information. For example, users may be informed that their personal information data will be accessed when downloading an application (“Application”), and then reminded again before the application accesses the personal information data.

[0065] Furthermore, the purpose of this disclosure is to manage and process personal information data to minimize the risk of unintentional or unauthorized access or use. Risk can be minimized by limiting data collection and deleting data once it is no longer needed. Additionally, and where applicable, including in certain health-related applications, data deidentification can be used to protect user privacy. Where appropriate, deidentification can be facilitated by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or characteristics of stored data (e.g., collecting location data at the city level rather than address level), controlling how data is stored (e.g., aggregating data among users), and / or other methods.

[0066] Therefore, while this disclosure broadly covers the use of information, including personal information data, to implement one or more of the various disclosed embodiments, it is also contemplated that various embodiments can be implemented without accessing personal information data. That is, various embodiments of the present invention will not be rendered inoperable due to the absence of all or part of such personal information data.

[0067] According to one embodiment, an electronic device is provided, comprising a foldable housing configured to bend about a bending axis; a flexible display panel overlapping the bending axis; a display cover layer overlapping the flexible display panel, the display cover layer having an inner surface facing the flexible display panel and an outer surface opposite thereto, and the display cover layer having a groove extending along the bending axis, the groove forming a locally thinned portion of the display cover layer; a polymer located in the groove; and a hardening structure embedded in the polymer, the hardening structure enhancing the outer surface's resistance to inward deformation over the locally thinned portion while allowing the display cover layer to bend about the bending axis.

[0068] According to another embodiment, the hardened structure comprises particles.

[0069] According to another embodiment, the particle has an average diameter that varies depending on the distance traveled through the polymer.

[0070] According to another embodiment, the particle has a first average diameter at a first distance from the outer surface to the polymer, and the particle has a second average diameter smaller than the first diameter at a second distance from the outer surface to the polymer greater than the first distance.

[0071] According to another embodiment, the average diameter of the particle varies smoothly and continuously depending on the distance traveled through the polymer.

[0072] According to another embodiment, the average diameter of the particle is characterized by a gradual change based on the distance traveled through the polymer.

[0073] According to another implementation, the average diameter is 0.5 micrometers to 50 micrometers.

[0074] According to another embodiment, the particles include glass particles.

[0075] According to another embodiment, the particles comprise glass beads.

[0076] According to another embodiment, the glass bead has a diameter of 1 micrometer to 50 micrometers, and the polymer contains inorganic nanoparticles with a diameter of less than 250 nm.

[0077] According to another embodiment, the hardening structure includes glass strips.

[0078] According to another embodiment, the glass strip has a rectangular cross-sectional profile with rounded corners.

[0079] According to another embodiment, the hardened structure includes glass strips and glass beads.

[0080] According to another embodiment, the polymer contains a certain concentration of nanoparticles with a diameter of less than 300 nm, the polymer has a first refractive index, the display cover layer has a second refractive index, and the concentration is configured to ensure that the difference between the first refractive index and the second refractive index is less than 0.05.

[0081] According to another embodiment, the display cover layer includes a glass layer and has a non-thinning portion, and the electronic device includes a polymer coating located on the inner surface of the non-thinning portion.

[0082] According to another embodiment, the polymer coating is an extension of the polymer in the groove.

[0083] According to another embodiment, the polymer coating and the polymer in the groove are different polymer materials.

[0084] According to one embodiment, an electronic device is provided, comprising a foldable housing configured to bend about a bending axis; a flexible display panel overlapping the bending axis; a glass display cover layer overlapping the flexible display panel, the glass display cover layer having an outer surface and an inner surface facing the flexible display panel, and the glass display cover layer having a recess in the inner surface extending along the bending axis and forming a locally thinned portion of the glass display cover layer; and a polymer located in the recess, the polymer comprising a glass strip that hardens the outer surface over the recess while allowing the glass display cover layer to bend about the bending axis.

[0085] According to another embodiment, the electronic device includes glass beads in the polymer.

[0086] According to one embodiment, a foldable display is provided, the foldable display including a foldable display panel configured to fold about a bending axis; and a display cover layer overlapping the foldable display panel, the display cover layer having a recess forming a partially thinned portion of the display cover layer extending along the bending axis, the display cover layer including a first glass layer overlapping the flexible display panel; a second glass layer attached to the inner surface of the first glass layer by a polymer layer, the second glass layer having a first half and a second half separated by a gap forming the recess; and a polymer comprising a glass-hardened structure located in the recess.

[0087] According to another embodiment, the glass-hardening structure includes glass beads.

[0088] According to another embodiment, at least one property of the glass bead varies depending on the distance traveled through the polymer layer.

[0089] According to another embodiment, the glass hardening structure includes a glass strip extending parallel to the bending axis.

[0090] According to another embodiment, the glass-hardened structure includes glass beads, the foldable display includes nanoparticles having a diameter of less than 200 nm in the polymer; a polymer coating located on the surface of the second glass layer facing the flexible display panel; and an anti-reflective coating located on the outer surface of the first glass layer opposite to the flexible display panel.

[0091] According to one embodiment, an electronic device is provided, comprising a foldable housing configured to bend about a bending axis; a flexible display panel overlapping the bending axis; a display cover layer overlapping the flexible display panel, the display cover layer having an inner surface facing the flexible display panel and an outer surface facing the opposite surface, and the display cover layer having a groove extending along the bending axis, the groove forming a locally thinned portion of the display cover layer; a polymer located in the groove; and dielectric particles embedded in the polymer, the dielectric particles enhancing the outer surface's resistance to inward deformation over the locally thinned portion while allowing the display cover layer to bend about the bending axis, the dielectric particles having an average diameter between 0.01 micrometers and 50 micrometers, and the average diameter varying according to the distance traveled through the polymer.

[0092] The foregoing description is merely illustrative and various modifications can be made to the described implementation scheme. The described implementation scheme can be implemented independently or in any combination.

Claims

1. An electronic device, comprising: A foldable housing configured to bend about a bending axis; A flexible display panel, wherein the flexible display panel overlaps with the bending axis; A display cover layer overlapping the flexible display panel, wherein the display cover layer has an inner surface facing the flexible display panel and an outer surface facing the opposite surface, and wherein the display cover layer has a recess extending along the bending axis, the recess forming a locally thinned portion of the display cover layer; a polymer located in the recess. And a hardener located in the recess, wherein a portion of the polymer is disposed between the hardener and the display overlay.

2. The electronic device of claim 1, wherein the hardened material comprises an elongated member extending parallel to the bending axis.

3. The electronic device of claim 2, wherein the elongated member comprises a glass strip.

4. The electronic device of claim 2, wherein the elongated member hardens the outer surface over the recess while allowing the display cover to bend about the bending axis.

5. The electronic device of claim 1, wherein the hardened material comprises parallel strips.

6. The electronic device of claim 5, wherein the parallel strip has a rectangular cross-sectional profile with rounded corners.

7. The electronic device of claim 1, wherein the hardened material comprises particles embedded in the polymer.

8. The electronic device of claim 7, wherein the particles comprise glass beads that enhance the resistance of the outer surface to inward deformation over the locally thinned portion, while allowing the display overlay to bend about the bending axis.

9. The electronic device of claim 1, wherein the hardened material comprises a transparent material.

10. The electronic device of claim 9, wherein the display cover layer comprises glass, and the transparent material of the hardened material comprises glass.

11. A foldable display, comprising: A foldable display panel, the foldable display panel being configured to fold about a bending axis; and a display cover layer, the display cover layer overlapping the foldable display panel, wherein the display cover layer has a recess that forms a locally thinned portion of the display cover layer extending along the bending axis; And a polymer comprising a hardened structure located in the recess, wherein a portion of the polymer is disposed between the hardened structure and the display overlay.

12. The foldable display of claim 11, wherein the hardened structure comprises a strip extending parallel to the bending axis.

13. The foldable display of claim 12, wherein the strip comprises a material selected from the group consisting of glass, sapphire, polymers and ceramics.

14. The foldable display of claim 11, wherein the display overlay comprises a glass layer and has a non-thinning portion, and the foldable display further comprises: A polymer coating is located on the inner surface of the non-thinned portion.

15. The foldable display of claim 14, wherein the polymer coating is an extension of the polymer in the recess.

16. The foldable display of claim 14, wherein the polymer coating and the polymer in the recess are different polymer materials.

17. An electronic device comprising: A foldable housing configured to bend about a bending axis; A flexible display panel, wherein the flexible display panel overlaps with the bending axis; The display cover layer overlaps with the flexible display panel, wherein the display cover layer has an outer surface and an inner surface facing the flexible display panel, and wherein the display cover layer has a recess in the inner surface, the recess extending along the bending axis and forming a locally thinned portion of the display cover layer; and a polymer located in the recess, the polymer comprising a hardened structure separated from the display cover layer.

18. The electronic device of claim 17, wherein the hardened structure comprises a strip, and a portion of the polymer is disposed between the strip and the display overlay.

19. The electronic device of claim 17, wherein the hardened structure comprises an elongated member embedded in the polymer.

20. The electronic device of claim 17, wherein the hardened structure comprises dielectric particles embedded in the polymer.

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