Flexible circuit board, display module and electronic device

Abstract

The application provides a flexible circuit board, a display module and an electronic device. The flexible circuit board comprises at least two conductive layers and at least one adhesive layer. Two adjacent conductive layers are connected by one adhesive layer. The adhesive layer comprises a first connecting part, a second connecting part and a folding part. The folding part is connected between the first connecting part and the second connecting part. The first connecting part and the second connecting part can be folded and unfolded relative to each other. The folding part can be bent. The folding part is provided with a plurality of opening structures. The plurality of opening structures penetrate the folding part along the thickness direction of the folding part. The plurality of opening structures are arranged in an array. The embodiment of the application can avoid the phenomenon that the flexible circuit board is wrinkled during folding. The wrinkling of the flexible circuit board does not affect the flatness of the display screen of the electronic device. The folding position of the display screen does not bring bad visual experience to the user.

Description

Technical Field

[0001] This application relates to the field of electronics, specifically to a flexible circuit board, a display module, and an electronic device. Background Technology

[0002] Currently, foldable electronic devices typically require flexible circuit boards to electrically connect the circuit boards under the two folded displays. However, wrinkles can easily form at the folding points of these flexible circuit boards, resulting in unevenness in the folded area of ​​the display and affecting the display quality of the electronic device. Summary of the Invention

[0003] The embodiments of this application provide a flexible circuit board, a display module, and an electronic device, which can avoid wrinkles in the flexible circuit board during folding, prevent wrinkles in the flexible circuit board from affecting the flatness of the electronic device's display screen, and prevent the folding position of the display screen from causing unpleasant visual experience for the user.

[0004] In a first aspect, this application provides a flexible circuit board, including at least two conductive layers and at least one adhesive layer. Two adjacent conductive layers are connected by an adhesive layer. The adhesive layer includes a first connecting portion, a second connecting portion, and a folding portion. The folding portion is connected between the first connecting portion and the second connecting portion. The first connecting portion and the second connecting portion can be folded and unfolded relative to each other. The folding portion can be bent. The folding portion is provided with multiple opening structures. The multiple opening structures penetrate the folding portion along the thickness direction of the folding portion. The multiple opening structures are arranged in an array.

[0005] In this embodiment, the folded portion can be bonded to the bending position of the two conductive layers. When the flexible circuit board is folded, the connection strength between the folded portion and the conductive layers is high, and the folded portion is less likely to delaminate from the conductive layers. This avoids the flexible circuit board delaminating and touching the display screen of the electronic device, which could cause wrinkles at the bending position of the display screen, thus preventing unevenness in the folded area of ​​the display screen and ensuring that the display effect is not affected.

[0006] Furthermore, the perforated structure reduces the stiffness of the adhesive layer, making it easier to bend and allowing the folded portion to adapt more readily to the shape changes of adjacent conductive layers. This ensures coordinated deformation between layers during bending. It also prevents excessive differences in properties such as the elastic modulus between the adhesive and conductive layers, avoiding excessive stress concentration during bending of the flexible circuit board and preventing delamination between the adhesive and conductive layers. Additionally, it prevents irregular shapes of the delaminated conductive layer from contacting the folded area of ​​the display screen, thus avoiding separation between the display screen and other components. This prevents impacting the bending reliability and appearance of the electronic device's display module, ensuring the relative position of the folded area of ​​the flexible circuit board and the folded area of ​​the display screen conforms to preset standards, guaranteeing that the display effect is not affected.

[0007] In one possible implementation, the folded portion includes a first region, a second region, and a third region, which are arranged sequentially along the extending direction of the folded portion, with the opening structure located in the second region.

[0008] In this embodiment, the first and third regions are the edge regions at both ends of the folded portion. In actual use, stress concentration is more likely to occur at the connection between the edge region of the conductive layer and the edge region of the adhesive layer, causing the adhesive layer and the conductive layer to easily separate. By not providing openings in the first and third regions at the edge of the adhesive layer, the bonding area between the adhesive layer and the conductive layer is increased, the connection strength between the adhesive layer and the conductive layer is improved, and separation of the edge region of the folded portion of the adhesive layer from the conductive layer is prevented. This avoids the raised conductive layer pressing against the display screen, which could cause unevenness in the display screen and lead to a poor visual experience for the user.

[0009] Furthermore, an opening structure is provided in the second region, making the middle area easier to bend. This allows the second region of the folded section to more easily adapt to the shape changes of the two adjacent conductive layers. This ensures coordinated deformation between the layers during bending, preventing excessive stress concentration on the flexible circuit board during bending, which could lead to delamination between the adhesive and conductive layers. It also ensures that the folding position of the flexible circuit board does not affect the shape of the display screen during folding, thus guaranteeing normal display performance.

[0010] In one possible implementation, the folded portion includes a first surface and a second surface, which are disposed opposite to each other. Each opening structure includes a first opening and a second opening, with the first opening located on the first surface and the second opening located on the second surface.

[0011] When the folded part is in the flattened state, the opening diameter of the first opening is the first diameter, and the opening diameter of the second opening is the second diameter. When the folded part is in the folded state, the first surface is the inner surface of the folded part, the second surface is the outer surface of the fold, the opening diameter of the first opening is the third diameter, which is smaller than the first diameter, and the opening diameter of the second opening is the fourth diameter, which is larger than the second diameter.

[0012] In this embodiment, during the folding process of the flexible circuit board, the opening structure deforms, allowing the shape of the folded portion to adapt to the folding shape of the conductive layer. The end of the opening structure facing inward can be compressed, thereby reducing the stress on the first surface, while the end facing outward can be stretched, thereby reducing the stress on the second surface. The opening structure reduces the stress on the folded portion, preventing excessive stress from causing deformation and delamination from the conductive layer. This ensures that the folding position of the flexible circuit board does not affect the shape of the display screen during the folding process, thus ensuring the normal display effect.

[0013] In one possible implementation, the depth of the opening structure is greater than or equal to the thickness of the fold, and the diameter of the opening structure is smaller than the depth of the opening structure.

[0014] In this embodiment, the opening structure can be an elongated hole. This avoids the opening occupying too much of the surface area of ​​the folded part, ensuring that the bonding area between the folded part and the conductive part is large enough to give the folded part and the conductive part good connection strength and prevent the folded part and the conductive part from delaminating during the folding process.

[0015] In one possible implementation, the conductive layer includes a first insulating layer, a connecting layer, a metal layer, and a second insulating layer stacked sequentially, with the second insulating layers of two adjacent conductive layers connected by an adhesive layer.

[0016] In one possible implementation, the periphery of the second insulating layer protrudes relative to the periphery of the adhesive layer.

[0017] In this embodiment, stress concentration is more likely to occur at the edge of the conductive layer. The edge of the second insulating layer of the conductive layer is not connected to the adhesive layer, which can avoid the edge of the conductive layer from delaminating with the edge of the adhesive layer and prevent the flexible circuit board from contacting the display layer, thus avoiding display defects of the display layer.

[0018] In addition, recessing the periphery of the adhesive layer relative to the periphery of the conductive layer can prevent the adhesive structure of the adhesive layer from overflowing from the periphery of the conductive layer, thus avoiding the formation of additional stress points by overflowing adhesive dots, which would increase the risk of equipment failure during long-term use.

[0019] Secondly, this application also provides a display module, including a display layer and a flexible circuit board as described above. The display layer includes a first part, a second part, and a bent part. The display layer is connected to the conductive layer of the flexible circuit board. The first part is stacked with the first connection part of the adhesive layer in the thickness direction. The second part is stacked with the second connection part of the adhesive layer in the thickness direction. The bent part is stacked with the folded part of the adhesive layer in the thickness direction.

[0020] In one possible implementation, the periphery of the display layer protrudes relative to the periphery of the flexible circuit board.

[0021] In one possible implementation, the display module further includes a support layer connected to the side of the flexible circuit board opposite to the display layer.

[0022] Thirdly, this application also provides an electronic device, including a first middle frame, a second middle frame and a display module as described above, wherein the first middle frame and the second middle frame are foldable and unfoldable relative to each other, and the side of the support layer away from the conductive layer is connected to the first middle frame and the second middle frame. Attached Figure Description

[0023] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application;

[0025] Figure 2 yes Figure 1 An exploded view of the electronic device shown;

[0026] Figure 3 yes Figure 2 The diagram shown is a structural schematic of the display module.

[0027] Figure 4 yes Figure 3 The diagram shows the structure of the flexible circuit board.

[0028] Figure 5 yes Figure 4 The diagram shows a cross-sectional view of the conductive layer.

[0029] Figure 6 yes Figure 4 A schematic diagram of the flexible circuit board from another angle is shown.

[0030] Figure 7 yes Figure 6 The diagram shows the structure of the adhesive layer.

[0031] Figure 8 yes Figure 7 The diagram shows a cross-sectional view of the adhesive layer in a folded state. Detailed Implementation

[0032] The specific embodiments of this application will now be described in more detail with reference to the accompanying drawings. Although exemplary embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in other ways different from those described herein, and therefore, this application is not limited to these embodiments.

[0033] For ease of understanding, the terminology used in the embodiments of this application will be explained first.

[0034] And / or: This is simply a way of describing the relationship between related objects. It indicates that there can be three kinds of relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0035] Multiple: refers to two or more.

[0036] Connection: should be interpreted broadly. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through an intermediary.

[0037] The specific embodiments of this application will now be clearly described in conjunction with the accompanying drawings.

[0038] Please see Figure 1 , Figure 1 This is a schematic diagram of the structure of the electronic device 1000 provided in the embodiments of this application. Figure 2 yes Figure 1 The diagram shows an exploded view of the electronic device 1000. This application provides an electronic device 1000. For ease of description, the width direction of the electronic device 1000 is defined as the Y direction, the length direction as the X direction, and the thickness direction as the Z direction. The X, Y, and Z directions are mutually perpendicular. It should be noted that... Figure 1 The dimension of the electronic device 1000 in the X direction can also be smaller than the dimension of the electronic device 1000 in the Y direction. In this embodiment, the X direction is simply defined as the axial direction of the folding axis of the electronic device.

[0039] For example, electronic device 1000 can be a smart consumer electronic device such as a mobile phone, tablet computer, or laptop computer. Alternatively, electronic device can also be a wearable device such as augmented reality (AR), virtual reality (VR), smart glasses, smart goggles, smartwatches, smart bracelets, wireless headphones, bone conduction wireless headphones, neckband wireless headphones, or true wireless stereo (TWS) headphones.

[0040] In this embodiment, a mobile phone is used as an example to illustrate the electronic device 1000. The electronic device 1000 shown in this embodiment is an electronic device capable of being folded once. In some other embodiments, the electronic device 1000 may also be an electronic device capable of being folded multiple times (more than twice). In this case, the electronic device 1000 may include multiple parts, two adjacent parts may be folded relatively close together until the electronic device 1000 is in a folded state, and two adjacent parts may be unfolded relatively far apart until the electronic device 1000 is in a flattened state.

[0041] Please continue reading. Figure 2 The electronic device 1000 may include a first housing 100, a second housing 200, a motherboard 300, a first middle frame 400, a second middle frame 500, a hinge mechanism 600, and a display module 700.

[0042] The first middle frame 400 and the second middle frame 500 are respectively mounted on the first housing 100 and the second housing 200, and the pivot mechanism 600 is located between the first middle frame 400 and the second middle frame 500. The pivot mechanism 600 is connected to the first housing 100 and the second housing 200. The main board 300 can be mounted on the first middle frame 400 and / or the second middle frame 500. The display module 700 covers the first middle frame 400 and the second middle frame 500 and is connected to the first housing 100 and the second housing 200.

[0043] In this embodiment, the first housing 100 and the second housing 200 can protect the internal components of the electronic device 1000 and greatly reduce the probability of screen damage. The pivot mechanism 600 realizes the rotation between the first housing 100 and the second housing 200 to realize the folding or opening of the electronic device 1000.

[0044] The motherboard 300 can be electrically connected to the display module 700. The motherboard 300 may have functions such as power management, communication interface, control and management. The motherboard 300 is the central hub for connecting and coordinating the various hardware components in the electronic device 1000.

[0045] Currently, foldable electronic devices typically require flexible circuit boards to electrically connect the internal electrical components of the two folded parts. However, wrinkles are prone to form at the folding points of these flexible circuit boards, resulting in unevenness in the corresponding display screen area and affecting the display quality of the electronic device.

[0046] This application provides a display module 700 that can prevent wrinkles from forming on the flexible circuit board during folding, thus avoiding the wrinkles affecting the flatness of the display layer of the electronic device 1000 and preventing the folding position of the display layer from causing an unpleasant visual experience for the user. The following detailed description, in conjunction with the accompanying drawings, illustrates specific embodiments.

[0047] Please see Figure 3 , Figure 3 yes Figure 2 The diagram shows the structure of the display module 700. The display module 700 may include a display layer 710, a flexible circuit board 720, and a support layer 730. The display layer 710, the flexible circuit board 720, and the support layer 730 are stacked sequentially along the thickness direction of the display module 700.

[0048] It should be noted that, Figure 3The purpose of this illustration is solely to depict the positional relationship between the display layer 710, the flexible circuit board 720, and the support layer 730, and it is not intended to specifically limit the connection positions, specific structures, or quantities of the various devices. Furthermore, the structures illustrated in this application's embodiments do not constitute a specific limitation on the display module 700. In other embodiments of this application, the display module 700 may include more or fewer components than illustrated, or combine certain components, or split certain components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of both.

[0049] The display layer 710 includes a first portion 711, a second portion 712, and a bending portion 713. The bending portion 713 is located between the first portion 711 and the second portion 712, and the bending portion 713 can be bent, causing the first portion 711 and the second portion 712 to fold relative to each other. The display surfaces of the first portion 711, the second portion 712, and the bending portion 713 together constitute a screen. In this embodiment, the display layer 710 uses a flexible screen, such as an organic light-emitting diode (OLED) screen, an active-matrix organic light-emitting diode (AMOLED) screen, a mini organic light-emitting diode (MLED) screen, a micro organic light-emitting diode (MOLED) screen, a microorganic light-emitting diode (MOLED) screen, or a quantum dot light-emitting diode (QLED) screen. The first portion 711 and the second portion 712 are also bendable when not fixed.

[0050] Please see Figure 4 , Figure 4 yes Figure 3The diagram shows the structure of the flexible circuit board 720. The flexible circuit board 720 is connected to the non-display surface of the display layer 710. The flexible circuit board 720 includes at least two conductive layers 721 and at least one adhesive layer 722, with adjacent conductive layers 721 connected by an adhesive layer 722. For example, the flexible circuit board 720 may include two conductive layers 721 and one adhesive layer 722. An adhesive layer 722 connects the two conductive layers 721. Alternatively, the flexible circuit board 720 may include three conductive layers 721 and one or two adhesive layers 722. The three conductive layers 721 are stacked. Adjacent conductive layers 721 are connected by an adhesive layer 722. Furthermore, the flexible circuit board 720 may also include four conductive layers 721 and three adhesive layers 722. The four conductive layers 721 are stacked. Adjacent conductive layers 721 are connected by an adhesive layer 722. It should be noted that the embodiments of this application do not impose specific limitations on the number of conductive layers 721 and adhesive layers 722 of the flexible circuit board 720.

[0051] The conductive layer 721 includes a first conductive portion 7211, a second conductive portion 7212, and a first folded portion 7213. The first folded portion 7213 connects the first conductive portion 7211 and the second conductive portion 7212. The first conductive portion 7211, the first folded portion 7213, and the second conductive portion 7212 are arranged sequentially along the Y direction. The first folded portion 7213 is bendable so that the first conductive portion 7211 and the second conductive portion 7212 can unfold relative to a folding mechanism.

[0052] For example, please refer to Figure 5 , Figure 5 yes Figure 4 The diagram shows a cross-sectional view of the conductive layer 721. The conductive layer 721 can be a flexible copper clad laminate (FCCL). The conductive layer 721 can include multiple sub-layers. The multiple sub-layers can be a first insulating layer 7214, a connecting layer 7215, a metal layer 7216, and a second insulating layer 7217 stacked sequentially. The second insulating layers 7217 of two adjacent conductive layers 721 are connected by an adhesive layer 722.

[0053] The metal layer 7216 is a sublayer with good conductivity within the conductive layer 721. The metal layer 7216 is typically made of metals (such as copper, aluminum, etc.) or highly doped semiconductor materials, which can provide conductive paths.

[0054] The first insulating layer 7214 and the second insulating layer 7217 are located on opposite sides of the metal layer 7216. The first insulating layer 7214 and the second insulating layer 7217 can prevent short circuits between the multiple conductive layers 721 and ensure that the currents between the multiple circuits do not affect each other. The first insulating layer 7214 and the second insulating layer 7217 can also isolate and protect the metal layer 7216, thereby preventing damage to the structure of the metal layer 7216.

[0055] The connecting layer 7215 connects the first insulating layer 7214 and the metal layer 7216, and can firmly bond the first insulating layer 7214 and the metal layer 7216 together to form an integral structure. This bonding effect not only enhances the bonding force between the first insulating layer 7214 and the metal layer 7216, but also improves the stability and reliability of the entire structure.

[0056] Please refer to the following: Figure 6 , Figure 6 yes Figure 4 This is a schematic diagram of the flexible circuit board 720 from another angle. An adhesive layer 722 connects two adjacent conductive layers 721. The periphery of the adhesive layer 722 can be recessed relative to the periphery of the conductive layer 721. That is, the periphery of the conductive layer 721 protrudes relative to the periphery of the adhesive layer 722.

[0057] In this embodiment, stress concentration is more likely to occur at the edge of the conductive layer 721. The edge of the conductive layer 721 is not connected to the adhesive layer 722, which can avoid the edge of the conductive layer 721 from delaminating with the edge of the adhesive layer 722, and prevent the flexible circuit board 720 from contacting the display layer 710 at the delamination position, which would lead to display defects in the display layer 710.

[0058] In addition, by recessing the periphery of the adhesive layer 722 relative to the periphery of the conductive layer 721, the adhesive structure of the adhesive layer 722 can be prevented from overflowing from the periphery of the conductive layer 721, thus preventing overflowing adhesive dots from forming additional stress points and increasing the risk of malfunction of the electronic device 1000 during long-term use.

[0059] Please continue reading. Figure 6The adhesive layer 722 includes a first connecting portion 7221, a second connecting portion 7222, and a folded portion. For ease of description, the folded portion of the adhesive layer 722 is defined as the second folded portion 7223. The second folded portion 7223 is connected between the first connecting portion 7221 and the second connecting portion 7222. The second folded portion 7223 is bendable, allowing the first connecting portion 7221 and the second connecting portion 7222 to be folded and unfolded relative to each other. The first connecting portion 7221 is connected between the first conductive portions 7211 of two adjacent conductive layers 721. The second connecting portion 7222 is connected between the second conductive portions 7212 of two adjacent conductive layers 721. The second folded portion 7223 is connected between the first folded portions 7213 of two adjacent conductive layers 721.

[0060] Please refer to the following: Figure 7 and Figure 8 , Figure 7 yes Figure 6 The diagram shows the structure of the adhesive layer 722. Figure 8 yes Figure 7 The diagram shows a cross-sectional view of the adhesive layer 722 in a folded state. The second folded portion 7223 includes a first surface 7224 and a second surface 7225, which are disposed opposite to each other.

[0061] The second fold portion 7223 is provided with multiple opening structures 7226, which penetrate the first surface 7224 and the second surface 7225 of the second fold portion 7223 along its thickness direction. The multiple opening structures 7226 are arranged in an array. Figure 8 As shown, each opening structure 7226 includes a first opening 7227 and a second opening 7228. The first opening 7227 is located on a first surface 7224, and the second opening 7228 is located on a second surface 7225. For example, the depth of the opening structure 7226 is greater than or equal to the thickness of the second folded portion 7223, and the diameter of the opening structure 7226 is smaller than its depth. When the depth of the opening structure 7226 is greater than the thickness of the second folded portion 7223, the extending direction of the opening structure 7226 is different from the thickness direction of the second folded portion 7223.

[0062] In this embodiment, the second folded portion 7223 can be bonded to the first folded portion 7213 of the two conductive layers 721. When the flexible circuit board 720 is folded, the connection strength between the second folded portion 7223 and the first folded portion 7213 is high, and the second folded portion 7223 is less likely to delaminate from the first folded portion 7213. This avoids the flexible circuit board 720 from delaminating and contacting the display layer 710 of the electronic device 1000, which could cause wrinkles at the bending position of the display layer 710. This also prevents unevenness in the folded area of ​​the display layer 710, ensuring that the display effect of the display layer 710 is not affected.

[0063] The perforated structure 7226 reduces the stiffness of the adhesive layer 722, making it easier to bend. This allows the second folded portion 7223 to more easily adapt to the shape changes of the two adjacent first folded portions 7213, ensuring coordinated deformation between the layers during bending. It also prevents excessive stress concentration during bending of the flexible circuit board 720 due to significant differences in properties such as the elastic modulus between the adhesive layer 722 and the conductive layer 721, which could lead to delamination between the adhesive layer 722 and the conductive layer 721. Furthermore, it prevents the irregular shape of the delaminated conductive layer 721 from contacting the bending area of ​​the display layer 710, ensuring that the relative position of the folded area of ​​the flexible circuit board 720 and the folded area of ​​the display layer 710 conforms to a preset standard, thus guaranteeing that the display effect of the screen is not affected.

[0064] The opening structure 7226 can be an elongated hole. This avoids the opening of the opening structure 7226 occupying too much of the surface area (first surface 7224 and second surface 7225) of the second folded portion 7223, ensuring that the bonding area between the second folded portion 7223 and the conductive layer 721 is large enough to give the second folded portion 7223 and the conductive layer 721 good connection strength and prevent the second folded portion 7223 and the conductive layer 721 from delaminating during the folding process.

[0065] For example, please refer to [the document / reference]. Figure 6 and Figure 7 The second fold portion 7223 includes a first region 7231, a second region 7232, and a third region 7233, which are sequentially arranged along the extending direction (X direction) of the second fold portion 7223. The first region 7231 and the third region 7233 do not have opening structures 7226. The second region 7232 has multiple opening structures 7226 arranged in an array.

[0066] In this embodiment, the first region 7231 and the third region 7233 are the edge regions at both ends of the second folded portion 7223 along its length. In actual use, stress concentration is more likely to occur at the connection between the edge region of the conductive layer 721 and the edge region of the adhesive layer 722, causing the adhesive layer 722 and the conductive layer 721 to easily separate. By not providing the opening structure 7226 in the first region 7231 and the third region 7233 at the edge position of the adhesive layer 722, the bonding area between the adhesive layer 722 and the conductive layer 721 is increased, the connection strength between the adhesive layer 722 and the conductive layer 721 is improved, and separation of the edge region of the second folded portion 7223 of the adhesive layer 722 from the conductive layer 721 is avoided. This prevents the raised conductive layer 721 from abutting against the display layer 710, thus avoiding unevenness in the display layer 710 and preventing unevenness in the display layer 710 from causing a poor visual experience for the user.

[0067] An opening structure 7226 is provided in the second region 7232, making the middle region easier to bend. This allows the second region 7232 of the second folded portion 7223 to more easily adapt to the shape changes of the two adjacent conductive layers 721. This ensures coordinated deformation between the layers during bending, preventing excessive stress concentration in the flexible circuit board 720 during bending, which could cause delamination between the adhesive layer 722 and the conductive layer 721. It also ensures that the folding position of the flexible circuit board 720 does not affect the shape of the display screen during folding, thus ensuring normal display performance.

[0068] When the display module 700 is in a flattened state, the second folding part 7223 is in a flattened state, the opening diameter of the first opening 7227 of the opening structure is the first diameter, and the opening diameter of the second opening 7228 is the second diameter.

[0069] When the display module 700 is in a folded state, the second folding portion 7223 is also folded. The first surface 7224 is the inner surface of the second folding portion 7223, and the second surface 7225 is the outer surface of the fold. At this time, the opening structure 7226 deforms. The opening diameter of the first opening 7227 is a third diameter, which is smaller than the first diameter. The opening diameter of the second opening 7228 is a fourth diameter, which is larger than the second diameter.

[0070] In this embodiment, during the folding process of the flexible circuit board 720, the opening structure 7226 deforms, allowing the shape of the second folded portion 7223 to adapt to the folding shape of the conductive layer 721. The end of the opening structure 7226 facing the inward side of the fold can be compressed, thereby reducing the stress on the first surface 7224. The end of the opening structure 7226 facing the outward side of the fold can be stretched, thereby reducing the stress on the second surface 7225. The opening structure 7226 reduces the stress on the second folded portion 7223, preventing excessive stress from causing deformation and delamination from the conductive layer 721. This ensures that the folding position of the flexible circuit board 720 does not affect the shape of the display layer 710 during the folding process, ensuring the normal display effect of the display layer 710.

[0071] The support layer 730 is connected to the conductive layer 721. The support layer 730 has a bendable area. The bendable area is located at the middle position in the Y direction of the support layer 730. In this embodiment, the support layer 730 can provide a stable base for supporting the flexible circuit board 720 and the display layer 710, ensuring that the flexible circuit board 720 and the display layer 710 can be unfolded or folded normally.

[0072] The side of the flexible circuit board 720 without the support layer 730 is connected to the display layer 710. The conductive layer 721 of the flexible circuit board 720 can be electrically connected to the display layer 710. The periphery of the adhesive layer 722 of the flexible circuit board 720 can be recessed relative to the periphery of the display layer 710.

[0073] Specifically, the first conductive portion 7211 is connected to the first portion 711 of the display layer 710. The first conductive portion 7211, the first connecting portion 7221 of the adhesive layer 722, and the first portion 711 of the display layer 710 are stacked in the Z direction. The second conductive layer 721 is connected to the second portion 712. The second conductive portion 7212, the second connecting portion 7222 of the adhesive layer 722, and the second portion 712 of the display layer 710 are stacked in the Z direction. The first folded portion 7213 is connected to the bent portion 713. The first folded portion 7213, the second folded portion 7223 of the adhesive layer 722, and the bent portion 713 of the display layer 710 are stacked in the thickness direction.

[0074] The side of the support layer 730 facing away from the conductive layer 721 can be fixedly connected to the mid-frame or housing of the electronic device 1000. The bendable area of ​​the support layer 730 can be stacked with the pivot mechanism 600 in the Z direction.

[0075] The above are exemplary embodiments of this application. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A flexible circuit board, characterized in that, It includes at least two conductive layers and at least one adhesive layer. Two adjacent conductive layers are connected by an adhesive layer. The adhesive layer includes a first connecting portion, a second connecting portion, and a folded portion. The folded portion is connected between the first connecting portion and the second connecting portion. The first connecting portion and the second connecting portion can be folded and unfolded relative to each other. The folded portion can be bent. The folded portion has a plurality of opening structures. The plurality of opening structures penetrate the folded portion along the thickness direction of the folded portion. The plurality of opening structures are arranged in an array.

2. The flexible circuit board according to claim 1, characterized in that, The folded portion includes a first region, a second region, and a third region. Along the extending direction of the folded portion, the first region, the second region, and the third region are arranged sequentially, and the opening structure is located in the second region.

3. The flexible circuit board according to claim 1 or 2, characterized in that, The folded portion includes a first surface and a second surface, which are disposed opposite to each other. Each of the opening structures includes a first opening and a second opening, with the first opening located on the first surface and the second opening located on the second surface. When the folded part is in a flattened state, the opening diameter of the first opening is the first diameter, and the opening diameter of the second opening is the second diameter. When the folded part is in a folded state, the first surface is the inner surface of the folded part, the second surface is the outer surface of the fold, the opening diameter of the first opening is a third diameter, the third diameter is smaller than the first diameter, and the opening diameter of the second opening is a fourth diameter, the fourth diameter is larger than the second diameter.

4. The flexible circuit board according to claim 3, characterized in that, The depth of the opening structure is greater than or equal to the thickness of the folded portion, and the diameter of the opening structure is smaller than the depth of the opening structure.

5. The flexible circuit board according to claim 1 or 2, characterized in that, The conductive layer comprises a first insulating layer, a connecting layer, a metal layer, and a second insulating layer stacked sequentially, with the second insulating layers of two adjacent conductive layers connected by an adhesive layer.

6. The flexible circuit board according to claim 5, characterized in that, The periphery of the second insulating layer protrudes relative to the periphery of the adhesive layer.

7. A display module, characterized in that, The invention includes a display layer and a flexible circuit board as described in any one of claims 1-6. The display layer includes a first portion, a second portion, and a bent portion. The display layer is connected to a conductive layer of the flexible circuit board. The first portion is stacked with a first connection portion of the adhesive layer in the thickness direction. The second portion is stacked with a second connection portion of the adhesive layer in the thickness direction. The bent portion is stacked with a folded portion of the adhesive layer in the thickness direction.

8. The display module according to claim 7, characterized in that, The periphery of the display layer protrudes relative to the periphery of the flexible circuit board.

9. The display module according to claim 8, characterized in that, The display module also includes a support layer, which is connected to the side of the flexible circuit board opposite to the display layer.

10. An electronic device, characterized in that, It includes a first middle frame, a second middle frame, and a display module as described in any one of claims 7-9, wherein the first middle frame and the second middle frame are foldable and unfoldable relative to each other, and the side of the support layer opposite to the conductive layer is connected to the first middle frame and the second middle frame.

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