HK40073634A - Lamination for flexible oled display - Google Patents

Description

Lamination for flexible OLED displays

Background

Electronic devices typically include a display component to display content to a user. For example, portable devices, personal digital assistants, wearable devices (such as smart watches and smart glasses), and the like typically include a display assembly for presenting content and information to a user. The electronic device may have a cover housing, such as a housing formed of plastic or metal, that exposes an active area of the display to display content. Some designs seek to maximize the effective area of the display panel relative to the overall device footprint in order to minimize the non-displayable area at the borders or edges of the display panel, thereby facilitating viewing from different angles and over a wider range for the user. Furthermore, the reduction in the relative size of the housing at the boundary of the active area of the display also enhances the overall aesthetics of the display assembly.

In order to maximize the active area of the display, a meandering housing, such as a meandering cover glass, is often used. However, the interface between the edge or border of the meandering cover glass and the curved peripheral display area typically carries most of the mechanical forces or stresses during the lamination process, thus increasing the complexity of manufacturing. Poor lamination often results in display components cracking, blistering, or wrinkling.

Disclosure of Invention

The present disclosure provides an electronic device that utilizes a flexible display panel having a plurality of embossed features to facilitate lamination to a meandering cover glass. In one example, a display assembly includes a flexible display panel positioned below a cover layer. The flexible display panel has a bent portion formed at a peripheral area of the flexible display panel. A plurality of relief features are formed in the curved portion of the flexible display panel.

In some examples, the flexible display panel further includes a planar portion formed on a central region of the flexible display panel. The planar portion has a circular shape. The planar portion has a polygonal shape or an irregular shape.

In some examples, the relief feature is a cut-out formed in a bend of the flexible display panel. The flexible display panel includes organic light emitting diodes. The flexible display panel further includes an active area formed in the bent portion of the flexible display panel. The active area includes an array of pixel circuits.

In some examples, the flexible display panel further includes an inactive area in the bend, and a plurality of electronic components formed on the inactive area in the bend. A display device integrated circuit is coupled to the flexible display panel. An accessory is coupled to the housing. A flexible display panel is located within the housing. The display device integrated circuit is disposed in an accessory proximate the housing.

In some examples, an optically clear adhesive couples the flexible display panel to the cover sheet layer. The relief features have an arcuate configuration, a triangular configuration, an elliptical configuration, or a semi-circular configuration. The display assembly is integrated in the wearable device. The curved portion of the flexible display panel has a curvature that matches the meandering side region of the cover layer.

Another aspect of the present disclosure includes an electronic device. The electronic device includes a cover plate layer. The flexible display panel has a planar central region and a meandering peripheral region. The serpentine peripheral region is bendable and the planar central region has a circular shape. A plurality of embossed features are formed in a serpentine periphery region of the flexible display panel.

In some examples, the meandering perimeter region of the flexible display panel includes an inactive area. A plurality of electronic components are formed on the inactive area in the meandering peripheral region. The relief features have an arcuate configuration, a triangular configuration, an elliptical configuration, or a semi-circular configuration. The pixel circuit array is formed in a meandering peripheral region of the flexible display panel.

Another aspect of the present disclosure includes a method for forming a display assembly for an electronic device. The method includes laminating a flexible display panel to a meandering coverboard layer, and positioning a plurality of embossed features formed in a meandering peripheral region of the flexible display panel under a meandering side region of the meandering coverboard layer.

Drawings

Fig. 1A-1B illustrate an example smart watch having a flexible display panel according to aspects of the present disclosure.

Fig. 2 is an example functional block diagram of an example electronic device, in accordance with aspects of the present disclosure.

Fig. 3A-3B illustrate cross-sectional views of a display assembly according to aspects of the present disclosure.

Fig. 4A-4B illustrate top views of active areas in a display assembly according to aspects of the present disclosure.

Fig. 5A-5B show perspective views of examples of peripheral portions of a flexible display panel with multiple bends before and after bending, according to aspects of the present disclosure.

Fig. 6A-6B show perspective views of another example of a perimeter portion of a flexible display panel with multiple bends before and after bending, according to aspects of the present disclosure.

Fig. 7A-7B illustrate top views of flexible curved displays with multiple bends defined by multiple relief features with different active area sizes, according to aspects of the present disclosure.

Fig. 8 illustrates a top view of an irregularly configured flexible curved display with multiple curves, according to aspects of the present disclosure.

Fig. 9 illustrates a top view of one example of a smart watch having a Display Device Integrated Circuit (DDIC) integrated therein, in accordance with aspects of the present disclosure.

Fig. 10 illustrates a top view of another example of a smart watch having a Display Device Integrated Circuit (DDIC) integrated therein, in accordance with aspects of the present disclosure.

Detailed Description

The present disclosure provides an electronic device that presents or displays information, content, or images to a user using a flexible display panel. The electronic device may be a portable device, a wearable device, or other suitable electronic device. In one example, the electronic device employed herein is a smart watch. An electronic device includes a flexible display panel having a plurality of bends embedded therein. The curvature of the bend matches the meandering side of the meandering cover sheet layer to which the flexible display panel is attached.

In one example, a plurality of embossed features are formed at a bend of a flexible display panel. When laminating a flexible display panel to a meandering cover sheet layer, the relief features formed at the bend may help to relieve local bending stresses or bending strains generated at the interface. An active area, such as an active content display area, may also be formed in the curved portion to provide a continuous display that enables a user to view the border area of the electronic device.

FIG. 1A illustrates an example electronic device. In this example, the electronic device is a wearable device, such as the smart watch 100. However, it should be understood that the wearable device may be any of a variety of wearable devices, such as a pendant, a head-mounted display, such as smart glasses, a smart helmet, an ear-bud, or any of a variety of other devices.

The smart watch 100 includes a watch body 145. The case 199 is for enclosing the watch body 145. Although in the illustrated example, the watch body 145 is circular or circular in shape, the watch body 145 may be any shape, such as rectangular, square, irregular, oval, polygonal, arbitrary, and the like. The watch body 145 may include a display assembly 150. The display assembly 150 includes a cover plate layer 141 and a display panel 142 disposed under the cover plate layer 141. In one example, the cover plate layer 141 may be made of various materials, such as metal, plastic, glass, ceramic, or any combination of these or other materials. In the example depicted herein, the cover plate layer 141 is made of a transparent material, such as glass.

The display panel 142 may be an Organic Light Emitting Diode (OLED) display or other suitable display. The display panel 142 may include a flat portion 120 and a bent portion 122. The bent portion 122 is formed at a frame region, a peripheral region, a boundary region, or an edge region of the display panel 142 with respect to the planar portion 120. The bend 122 allows an active area 124 (shown in fig. 1A as a shaded pattern) to extend from the planar portion 120 to a boundary/corner region of the watch body 145 to continuously display content, information, or images in the display panel 142. Thus, the continuous display of the display panel 142 from the planar portion 120 to the curved portion 122 may provide a wider viewing range and angle for the user, such as a high screen body ratio to achieve a "full screen" design, as well as enhance the overall aesthetic appearance of the watch body 145. The active area 124 includes an array of display pixels associated with pixel circuitry including at least one switching Thin Film Transistor (TFT) and at least one driver TFT. Each pixel circuit may be electrically connected to gate and data lines and communicate with drive circuits (such as gate and data drivers) located in inactive areas of display panel 142 to operate the associated pixel. It should be noted that various additional components, such as inverter circuits, multiplexers, electrostatic discharge (ESD) circuits, etc., may be located in the inactive area of the display panel 142, generating various signals for operating the pixels in the active area 124. In addition, the display panel 142 may also include components having different functions in addition to operating the pixels located in the active area 124. For example, the display panel 142 may include components for providing touch sensing operations, user authentication processes, such as fingerprint scanning, multi-stage pressure sensing processes, tactile feedback processes, and/or various other processes or operations for the electronics employed in the display panel 142.

The bend 122 of the display panel 142 may eliminate, reduce, or minimize dead space from the front of the display assembly 150. By employing the bent portion 122 at an edge, bezel, border, or peripheral region of the display panel 142, the inactive area of the display panel 142 may then be limited in the bent portion 122 to be folded to a vertical side or bottom side of the display panel 142, such as not visible from the front of a user, so the active area of the display in the display panel 142 is maximized and the aesthetics of the overall device may be enhanced.

In one example, display assembly 150 can include capacitive touch sensor electrodes for a capacitive touch sensor array or other touch sensor structure. The touch sensor electrode may be disposed on a touch layer interposed between the display panel 142 and the cover plate layer 141, or may be formed on the lower side of the cover plate layer 141, or may be combined on the flat portion 120 and a portion of the bent portion 122 of the display panel 142.

In one example, the planar portion 120 may have a rounded or circular shape. The planar portion 120 may also have an irregular, polygonal, or other suitable shape.

A plurality of embossed features 143 are formed in the bend 122 of the display panel 142. The relief features 143 may relieve mechanical or bending stresses associated with bending at the bend 122. The embossed features 143 may be cut-outs or cut-out structures that remove some material from the peripheral region of the display panel 142. The relief features 143 may be of any configuration, pattern, or dimension. In one example, the relief features 143 may be shaped in an arcuate configuration, a triangular configuration, an elliptical configuration, a semi-circular configuration, or other suitable configuration. In the examples described herein, some of the relief features 143 may be omitted entirely or may be altered from the form shown, for example, by forming more or fewer relief features 143, by relief features 143 of a different cross-section, number, or shape than those shown, or by other structures that mitigate mechanical stresses associated with bending at the bend 122.

The cover plate layer 141 may be attached or bonded to the display panel 142 through a lamination process. In one example, the cover sheet layer 141 includes a planar region 161 and a serpentine side region 162. The planar region 161 is bonded to the planar portion 120 of the display panel 142, and the meandering side region 162 is bonded to the curved portion 122 of the display panel 142. As shown in fig. 3, an adhesive material 302 may be used to bond the cover plate layer 141 to the display panel 142, minimizing interface defects, such as bubbles or gaps. The embossed features 143 formed in the bend 122 of the display panel 142 also help to minimize gaps or vent air during the lamination process in order to prevent wrinkles or cracks and provide a good conforming interface.

Wearable device 100 may include one or more accessories, such as a wristband 130. In other examples where wearable device 100 is a different device, the body of the device may have different types of accessories. For example, the pendant may include an accessory such as a necklace. Wristband 130 may be made of a variety of materials, such as metal, rubber, nylon, cotton, plastic, glass, ceramic, or any combination of these or other materials. Wristband 130 may be adapted to be worn on a person's wrist. For example, wristband 130 includes a strap 140. The band 140 may be adjusted to provide a secure and comfortable fit around the wearer's wrist. In other examples, the band may be a bracelet, such as for a looser fit, or other type of attachment mechanism.

The watch band 130 may further include a receptacle 170 adapted to secure the watch body 145 of the smart watch 100 to the watch band 130. For example, to accommodate the watch body 145, the receptacle 170 may have a similar shape to the watch body 145. Further, the receptacle 170 may include features such as grooves, hooks, locks, screws, pins, magnets, etc., which may interlock with features of the watch body 145 to ensure a secure attachment. Although a socket 170 is shown in this example, in other examples, wristband 130 may include other mechanical features, such as pins, screws, hooks, locks, etc., that secure wristband 130 directly to watch body 145.

In some examples, wristband 130 may be configured to contain electronic and/or mechanical components. For example, electronic components 172 are shown located inside socket 170. It should be noted that the electronic electronics 172 may be located in any suitable location of the smart watch 100, such as in the band 140. The electronic electronics 172 may include drive circuitry, such as gate drivers, display device integrated circuits, transmit (source) drivers, power supply (VDD) routing, electrostatic discharge (ESD) circuitry, multiplexing (mux) circuitry, data signal lines, etc., to transmit data from components in the watch body 145 to and/or receive data from other devices or circuits. The electronic component may further comprise an identification and/or authentication device, such as a Radio Frequency Identification (RFID) device, which may be linked to a user profile or account. The conductive traces 174 may be used to maintain electrical communication between the electronic components 172 and electronic components in the watch body 145 including the display panel 142.

Fig. 1B depicts another example of a smart watch 190 that is substantially similar to the smart watch 100 depicted in fig. 1A, except that the active area 124 of the display does not extend to the bend 122 of the display panel 142. For example, the active area 124 of the display is configured to be in the planar portion 120 without extending to the bend portion 122, maintaining the active area 124 in the planar portion 120 while forming the inactive area 125 in the bend portion 122. A plurality of embossed features 143 are formed in the bend 122 to facilitate lamination of the display panel 142 with the switchback side regions 162 of the cover sheet layer 140.

It should be noted that the area, size, dimensions of the active area formed in the display panel may vary based on different design, manufacturing, and cost considerations.

Fig. 2 is a block diagram of an example of a watch body 145 in a smart watch 100, 190 including a plurality of electronic components, including a display panel 142 laminated with a cover plate layer 140, according to aspects of the present disclosure. The example block diagrams depicted herein should not be viewed as limiting the scope of the disclosure or the use of features described herein. In the illustrated example, the watch body 145 may contain one or more processors 112, memory 114, and other components typically found in general purpose computing devices.

The memory 114 may store information, including instructions 116, accessible by the one or more processors 112, which may be executed by the one or more processors 112. The memory 114 may also include data 118 that may be retrieved, manipulated, or stored by the processor 112.

Further, as shown in fig. 2, the watch body 145 may include a user interface 120 that includes one or more input devices 111 and one or more output devices 113. For example, the input device 111 may include a touch screen 202 and the output device 113 may include a display panel 142. Other components, such as mechanical actuators, soft actuators, peripherals, sensors, and/or other suitable features may also be included in the user interface 120. It should be noted that the touch screen 202 and the display panel 142 described herein may refer to the same object that provides multiple functions. For example, the display panel 142 may not only display content but also provide a touch activated interface, referred to as a touch screen 202, with the touch screen 202 allowing a user to enter and actively interact with commands. In some examples, the touch screen 202 may be incorporated as a touch layer formed on the display panel 142, or as an underside layer formed on the lower surface of the cover sheet layer 140.

The user may be able to interact with the smart watch 100, 190 using the input device 111, such as opening a web page or email, composing a message, controlling a display or audio function, controlling a sensor to monitor heart rate or body temperature, positioning via GPS, and so forth. The watch body 145 may include one or more output devices, such as output device 113. For example, the output device 113 may include one or more speakers, transducers, or other audio outputs, a display panel 142, a haptic interface, or other tactile feedback to provide non-visual and non-audible information to the user. For example, the display panel 142 in the output device 113 may display visual information, content, or images, such as text, graphics, video, etc., to the user. As another example, speakers in the output device 113 may be used to play music, emit audio for navigation or other guidance, for multimedia files, for voice calls, for translating voice, and so forth. Further, haptic or tactile feedback in the output device 113 may be used to generate non-visual and non-audible alerts, such as by vibration.

The watch body 145 may include one or more sensors, such as sensor 115. For example, the sensors may include visual sensors, audio sensors, touch sensors, and the like. The sensors may also include motion sensors, such as inertial measurement units ("IMUs"). According to some examples, the IMU may include an accelerometer, such as a 3-axis accelerometer, and a gyroscope, such as a 3-axis gyroscope. The sensors may further include barometers, vibration sensors, thermal sensors, Radio Frequency (RF) sensors, magnetometers, barometric pressure sensors, heart rate sensors, body temperature sensors. Additional or different sensors may also be employed. In some examples, the sensors 115 may include sensors for detecting battery status, the presence of a wireless charging device, or any of a variety of other conditions.

The watch body 145 may include a communication interface 110. The communication interface 110 may enable the exchange of information with other devices. The communication interface 110 may include a communication receiver and transmitter system to modulate and transmit signals for data or signal transmission. The communication interface 110 may be controlled by a processor 112. In other examples, the communication interface 110 may alternatively be configured to transmit and/or receive data according to a wireless signal transmission standard, a bluetooth standard, or other suitable standard, among others.

The communication interface 110 may enable wireless network connections, wireless ad hoc connections, and/or wired connections. The communication system may be configured to support communication via cellular, LTE, 4G, 5G, WiFi, GPS, and other networking architectures. The communication interface 110 may be configured to supportBluetooth LE, Near Field Communication (NFC) standard, Qi standard, and non-networked wireless arrangements. The communication interface 110 may support a wired connection, such as a USB, micro-USB, USB type C, or other connector, for example to receive data and/or power from a laptop, tablet, smartphone, or other device.

The watch body 145 may include one or more accumulators, such as the accumulator 119 configured to receive and store the generated power. In one example, the accumulator 119 may be a battery.

Watch body 145 also includes a Display Device Integrated Circuit (DDIC)117, which may be in electrical communication with touch screen 202 and display panel 142 in user interface 120. Display Device Integrated Circuit (DDIC)117 may control and provide display panel 142 with a desired level of display resolution. Display Device Integrated Circuit (DDIC)117 provides an interface between processor(s) 112 and display panel 142. Display Device Integrated Circuit (DDIC)117 transmits electrical signals to activate an array of pixels in display panel 142 to ultimately produce an image on display panel 142.

Although not shown, the watch body 145 may also include other additional components. For example, the watch body 145 may include a location determination module, which may include a GPS chipset or other positioning system component. The location determination module may use information from sensors and/or data received or determined from a remote device (such as a wireless base station or wireless access point) to calculate or otherwise estimate the physical location of the watch body 145 and/or watchband 130. As another example, the watch body 145 may include one or more internal clocks. The internal clock may provide timing information that may be used for time measurement of applications and other programs run by the computing device, as well as for basic operation of the computing device, sensors, input/output terminals, GPS, communication systems, and the like.

Although the components shown in fig. 2 are included in the watch body 145, it should be noted that one or more of the components of fig. 2 may also be implemented or configured at other locations of the smart watch 100, such as the wristband 130.

Fig. 3A depicts a cross-sectional view of a display assembly 300 comprising a cover sheet layer 141 and a display panel 142 bonded by an adhesive material 302. In one example, the adhesive material 302 may be an Optically Clear Adhesive (OCA). It should be noted that the example depicted in fig. 3 is for illustration purposes only. For ease of description, some components, such as devices, transistors, signal lines, or other details or components, are not shown in fig. 3A.

Display assembly 300 generally includes a planar region 304 (such as a central region) and a meandering region 306 (such as a peripheral region) formed on an edge, bezel, border, or peripheral region of display assembly 300. Planar region 304 includes a planar region 161 in cover plate layer 141 that is bonded from display panel 142 to planar portion 120, while meandering region 306 includes meandering side regions 162 that are bonded from cover plate layer 141 to curved portions 122 from display panel 142. Planar area 304 has a substantially circular or rounded shape. It should be noted that planar area 304 may also be irregular, polygonal, or other suitable shape. The cover plate layer 141 may be a transparent material for protecting the display panel 142. The cover plate layer 141 may be formed of plastic or glass, and may be flexible or rigid. The meandering side region 162 of the cover layer 141 may provide a meandering surface having a desired curvature to fit to the bend 122 from the display panel 142.

The inflection zones 306 of the display assembly 300 provide a bezel-minimizing effect on the edges of the display assembly 300, thus providing an immersive visual experience 350 and aesthetic for the user and increasing the utilized active area of the display panel 142.

In one example, the display panel 142 may be a flexible display including a plurality of structures formed on the substrate 314. Fig. 3B depicts an enlarged view of a portion of display panel 142 having structures 360 formed in display panel 142. The structure 360 formed in the display panel 142 includes a pixel array including an organic light emitting diode structure. For example, a plurality of layers may be formed on the substrate 314 including the OLED structure for emitting light to display an image. The encapsulation layer 362 is formed on an organic light emitting material layer 364 on which a plurality of thin film transistor devices 366 are formed. Each pixel may be associated with a pixel circuit that includes at least one switching Thin Film Transistor (TFT) device and at least one drive TFT device. Each pixel circuit may be electrically connected to gate and data lines and in communication with drive circuits (such as gate and data drivers) to operate the associated pixel. A base layer, such as the substrate 314, is then formed in contact with the organic light emitting material layer 364. Substrate 314 may include a thin flexible plastic film formed from polyimide, polyethylene naphthalate (PEN), polyethylene terephthalate (PET), other suitable polymers, combinations of these polymers, and the like. Other suitable substrates that may be used to form substrate 314 include glass, metal foils covered with a dielectric, multi-layer polymer stacks, thin glass films bonded to thin polymers, polymer composite films comprising polymeric materials combined with nanoparticles or microparticles dispersed therein, and the like.

Fig. 4A-4B depict top views of display assemblies 402, 404 having different sized active areas 124A, 124B formed in the display panel 142. The display component 402 depicted in fig. 4A may be a top view of the smart watch 100 depicted in fig. 1A, while the display component 404 depicted in fig. 4B may be a top view of the smart watch 190 depicted in fig. 1B. A plurality of relief features 143, such as cut-outs, may be formed in the bend 122 to help relieve local bending stresses. In the example depicted in fig. 4A, the active area 124A is formed in the planar portion 120 and extends to the bend portion 122 of the display panel 142. Accordingly, the inactive area formed in the bent portion 122 is relatively minimized. The embossed features 143 formed in the bend 122 remove a portion of the active area from the display panel 142.

In contrast, in the example depicted in fig. 4B, the effective area 124B is formed in the planar portion 120 without extending to the bent portion 122. Thus, the bend 122 in the example depicted in fig. 4B includes a relatively large inactive area 125, such as where no pixel array is formed. The relatively large size of the inactive area 125 may allow various peripheral circuits or components formed therein to facilitate electrical communication between the display panel 142 and other components disposed in the watch body 145, such as a processor or DDIC. Thus, with different design requirements, different sized inactive areas formed in the bend 122 may be selected to facilitate positioning of various peripheral drivers, circuits, or components.

In one example, the bend 122 is bendable, such as bendable tabs, which may create a tortuous surface that mates with the curvature defined by the tortuous side regions 162 of the cover sheet layer 141. Thus, a good mating interface can be obtained by matching curvatures between them, thereby eliminating interface defects, cracks, or wrinkles during the lamination process. When the bend 122 is connected with the planar segment 120, the bend 122 defined between the relief features 143 can flare outward from a rounded edge 405 (otherwise referred to as a perimeter or rounded end) of the planar segment 120.

In some examples, ink or other material may be applied to the cover plate layer 141 to cover or disguise the embossed features 143 for the overall aesthetic appearance of the display assemblies 402, 404. For example, ink or other material may be applied in a pattern or mask corresponding to the relief features 143. Further, the ink may be colored to match the color of the active area of the display assembly. Thus, the relief features 143 may be hidden or disguised.

Fig. 5A-5B depict enlarged views of a portion of the bend portion 122 (such as a bendable flap) of the display panel 142 before and after the bend portion 122 is bent along the bend line, with the active area 124 extending to the bend portion 122. A plurality of bend lines 508 may be formed in the display panel 142 such that the bend portions 122 may be bendable and/or foldable along the bend lines 508. Fig. 5A depicts an example of bend portion 122 of display panel 142 before bending, and fig. 5B depicts an example of bend portion 122 of display panel 142 after bending along bend line 508. A plurality of embossed features 143 are formed at the bend 122 of the display panel 142. In one example, the bend 122 may be curved along bend line 508 with a radius of less than 3mm, such as less than 2 mm. When the active area 214 extends into the bend 122, the functional device (such as an OLED stack) formed in the active area 214 may be fabricated in a manner that provides flexibility so that the functional device may be folded without degrading the device structure.

When the active area 124 extends into the bend 122 of the display panel 142, content, information, or images may be shown in the bend 122. For example, features 575, such as alphanumeric, roman numerals, word numerals, dots, bars, or other suitable features for depicting time and/or information may be displayed in the curved portion 122. In addition, the active area 124 in the curved portion may also be used to show symbols, text messages, or other information that does not require a large display size, such as battery power, telecommunication signal strength level, biometric information, e.g., heart beat, or other information set by the user. A plurality of electronic components, such as drivers 506a or circuits 506b, may be formed on the inactive area 502 in the flexure 122. The inactive area 502 in the bend 122 may provide space to facilitate positioning of various peripheral drivers, circuits, or components thereon, such as the driver 506a or the circuit 506 b. The plurality of signal lines 504 may be used to provide electrical connections between peripheral drivers, circuits, or components to the processor or display panel 142 located elsewhere on the smart watch 100, 190. Thus, the peripheral drivers, circuits or components may be folded to the side or even the bottom of the display panel 142, thereby maximizing the displayable active area formed on the front side of the smart watch 100.

Fig. 6A-6B depict enlarged views of a portion of bend portion 122 of display panel 142 before and after bend portion 122 is bent along bend line 602, wherein active area 124 is defined in planar portion 120 without extending to extension portion 122. A plurality of bend lines 602 may be formed in display panel 142 such that bend 122 may be bendable and/or foldable along bend lines 602. Fig. 6A depicts an example of bend portion 122 of display panel 142 before bending, and fig. 6B depicts an example of bend portion 122 of display panel 142 after bending along bend line 602. A plurality of embossed features 143 are formed at the bend 122 of the display panel 142. A plurality of electronic components, such as drivers 506a or circuits 506b, may be formed on the inactive area 125 in the flexure 122. Since the active area 124 does not extend into the bend 122, the relatively larger size of the inactive area 125 in the bend 122 may provide more available space to facilitate positioning of various peripheral drivers, circuits, or components thereon, such as the driver 506a or the circuit 506 b. The plurality of signal lines 504 may be used to provide electrical connections between peripheral drivers, circuits, or components to the processor or display panel 142 located elsewhere on the smart watch 100, 190. Thus, the peripheral drivers, circuits or components may be folded to the side or even the bottom of the display panel 142, thereby maximizing the effective area formed on the front face of the front side of the smart watch 100.

Fig. 7A-7B depict top views of the display panel 124 prior to bonding to the cover plate layer 141, where different sized active areas 124a, 124B are formed in the display panel 142. A plurality of relief features 143, such as cut-outs, may be formed in the bend 122 to help relieve local bending stresses. In the example depicted in fig. 7A, the effective area 124b is formed in the planar portion 120 without extending to the curved portion 122 of the display panel 142. Accordingly, the bend 122 in the example shown in fig. 7A includes a relatively large inactive area 125, such as a pixel array that is not formed thereon. In the example depicted in fig. 7B, the effective area 124a is formed in the planar portion 120 and further extends to the curved portion 122. Therefore, the ineffective area 502 formed in the bent portion 122 is relatively minimized. In the example depicted in fig. 7A-7B, a total of twelve embossed features 143 are formed in the display panel 142, thus defining a total of twelve bends 122 in a perimeter region, such as an end or perimeter, of the display panel. It should be noted that the relief features 143 may be formed in any number, such as four, twelve, twenty, or any suitable number. In one example, the planar portion 120 may have a circular configuration, an elliptical configuration, or other substantially circular configuration. It should be noted that the bend 122 may or may not be continuously formed around the perimeter of the display panel 142. For example, some of the bends 122 may be skipped to allow for additional features formed in the display panel 124, such as buttons or a crown. Further, some of the bends 122 may have different dimensions to accommodate different design requirements.

The central region, such as planar portion 120, may have a circular or rounded configuration. A perimeter region, such as bend 122, may extend from planar segment 120 and flare to form a circular edge 702 or circular perimeter of planar segment 120.

Fig. 8 depicts a top view of an example display panel 800 having an irregular configuration, such as a polygonal configuration or other suitable configuration. A plurality of embossed features 850 may be formed at an edge or perimeter region of the display panel 800. The display panel 800 may include a planar portion 820 and a plurality of bent portions 804 connected to the planar portion 820. The bend 804 may be bendable or foldable along bend line 806. Similarly, as described above, the active area may be formed or limited only in the planar portion 820 of the display panel 800 or may be formed in the planar portion 820 extending to the bent portion 804 at the same time, based on different design requirements.

Fig. 9 depicts a top view of a portion of an example smart watch 800. The smart watch 800 includes a display assembly 402 (not visible from the top) disposed on the watch body. A plurality of embossed features 143 are formed in the bend 122 of the display panel 142, wherein the cover plate layer 141 is laminated on the display panel 142. The tail 937 may be formed and connected to the display panel 142. The tail 937 may be bendable. Thus, the tail 937 may be folded to the back side of the display panel 142. In the example depicted in fig. 9, the Display Device Integrated Circuit (DDIC)804 is disposed on the rear portion 937 of the display panel 142. Tail 937 may provide additional real estate to facilitate formation of DDIC 804 or other additional peripherals, drivers, or circuits thereon. Alternatively, the DDIC 804 or other additional peripherals, drivers, or circuits may also be disposed on or in an accessory (such as a wristband) that is attached to a portion of the housing 905. In this example, a Display Device Integrated Circuit (DDIC)804 may be disposed on a watchband that is connected in close proximity to the display assembly 402. The location of Display Device Integrated Circuit (DDIC)804 is selected to be in close proximity to display panel 142 to minimize electrical signal transmission or travel electrical signal distance between display panel 142 and DDIC 804. It should be noted that other peripheral devices, drivers, or circuits may also be disposed in close proximity to the display panel 142.

It should be noted that the area 904 of the display panel 142 in which the tail 937 is attached may be configured with relatively larger sized relief features 905, e.g., relatively larger sized cutout structures, to facilitate coupling the tail 937 to the display panel 142. In the example depicted in fig. 9, the tail 937 is formed on one side 803 of the display panel 142. In this example, eleven bendable tabs 122 are formed in the display panel 142 along with the tail 937. Alternatively, the tails 937, 807 can be formed at two opposing ends of the display assembly 402, such as the lower side 803 and the upper side 811, as shown in fig. 10. In this example, ten bendable tabs 122 are formed in the display assembly 402 along with two tails 937, 807. Accordingly, DDIC 804 or other peripheral devices, drivers, or circuits 812 may be located or distributed between two sides (such as lower side 803 and upper side 811) of display panel 142 relative to display assembly 402. This may provide an even or equal distribution over different locations of the smart watch 800.

The present disclosure provides an electronic device utilizing a flexible display panel with a plurality of embossed features formed in a peripheral bend of the flexible display panel. The plurality of embossed features may facilitate lamination of the flexible display panel to the circuitous cover sheet layer. The flexible display panel may have a plurality of embossed features formed in the curved portion of the edge periphery of the flexible display panel in a circular configuration with the plurality of embossed features formed in the curved portion of the edge periphery of the flexible display panel. The plurality of relief features may help to relieve local bending stresses, thereby eliminating the possibility of cracks or wrinkles forming during the lamination process. The active area for displaying images may extend to the bend of the flexible display panel, thereby providing a wide viewing range and/or angle for the user and enhancing the overall aesthetic appearance of the electronic device.

Unless otherwise specified, the above-described alternative examples are not mutually exclusive, but may be implemented in various combinations to achieve unique advantages. As these and other variations and combinations of the features discussed above can be utilized without departing from the subject matter defined by the claims, the foregoing description of the embodiments should be taken by way of illustration rather than by way of limitation of the subject matter defined by the claims. Additionally, the examples described herein are provided, and terms expressed as "such as," "including …," etc., should not be construed to limit the claimed subject matter to the specific examples; rather, these examples are intended to illustrate only one of many possible embodiments. Moreover, the same reference numbers in different drawings may identify the same or similar elements.

Claims (20)

1. A display assembly, comprising:

a flexible display panel located below a cover sheet layer, the flexible display panel having a bend formed in a peripheral region of the flexible display panel; and

a plurality of embossed features formed in the bend of the flexible display panel.

2. The display assembly of claim 1, wherein the flexible display panel further comprises a planar portion formed on a central region of the flexible display panel.

3. The display assembly of claim 2, wherein the planar portion has a circular shape.

4. The display assembly of claim 2, wherein the planar portion has a polygonal shape or an irregular shape.

5. The display assembly of claim 1, wherein the embossed feature is a cut-out portion formed in the bend of the flexible display panel.

6. The display assembly of claim 1, wherein the flexible display panel comprises eleven or twelve embossed features.

7. The display assembly of claim 1, wherein the flexible display panel further comprises an active area formed in the bend of the flexible display panel.

8. The display assembly of claim 7, wherein the active area comprises an array of pixel circuits.

9. The display assembly of claim 1, wherein the flexible display panel further comprises an inactive area in the bend, and a plurality of electronic components formed on the inactive area in the bend.

10. The display assembly of claim 1, further comprising:

a display device integrated circuit coupled to the flexible display panel.

11. The display assembly of claim 10, further comprising an accessory coupled to a housing, wherein the flexible display panel is located within the housing, and wherein the display device integrated circuit is disposed in the accessory proximate to the housing.

12. The display assembly of claim 1, further comprising:

an optically clear adhesive coupling the flexible display panel to a cover plate layer.

13. The display assembly of claim 1, wherein the relief features have an arcuate configuration, a triangular configuration, an elliptical configuration, or a semi-circular configuration.

14. The display assembly of claim 1, wherein the display assembly is integrated in a wearable device.

15. The display assembly of claim 1, wherein the curved portion of the flexible display panel has a curvature that mates with a tortuous side region of a cover sheet layer.

16. An electronic device, comprising:

a cover plate layer; and

a flexible display panel having a planar central region and a serpentine peripheral region, wherein the serpentine peripheral region is bendable and the planar central region has a circular shape;

a plurality of relief features formed in the serpentine peripheral region of the flexible display panel.

17. The electronic device defined in claim 16 wherein the serpentine perimeter region of the flexible display panel comprises an inactive area and further comprising a plurality of electronic components formed on the inactive area in the serpentine perimeter region.

18. The electronic device of claim 16, wherein the relief features have an arcuate configuration, a triangular configuration, an elliptical configuration, or a semi-circular configuration.

19. The electronic device of claim 16, further comprising:

an array of pixel circuits formed in the serpentine peripheral region of the flexible display panel.

20. A method for forming a display assembly for an electronic device, comprising:

laminating the flexible display panel to a meandering cover sheet layer; and

positioning a plurality of embossed features formed in a serpentine peripheral region of the flexible display panel under a serpentine side region of the serpentine bezel layer.