Flexible circuit board folding structure for ar

Abstract

The utility model relates to AR equipment technical field, and disclose AR flexible circuit board folding structure, including the flexible circuit board that is made of the protection outer layer, reinforcing layer and conductive layer from outside to inside through acrylic adhesive hot pressing lamination, the protection outer layer is 25um polyimide film, has 10um nanometer ceramic coating outside, is equipped with first bending area and first transition structure, the reinforcing layer is 50um plain weave aramid fiber fabric, has second bending area, second transition structure and both sides reinforcing rib, the conductive layer contains three layers 50um polyimide dielectric layer, top has parallel copper foil, the dielectric layer near copper foil place bonds 3um nanometer silicon dioxide reinforcing phase, the structure through each layer bending area, transition structure and strengthening design, improve the bending resistance and structural stability, guarantee AR equipment folding time signal stable transmission, prolong the service life.

Description

Technical Field

[0001] This utility model relates to the field of AR device technology, specifically to a folding structure for flexible circuit boards used in AR. Background Technology

[0002] With the rapid development of AR technology, AR glasses and other devices are trending towards miniaturization and lightweight design, while their functions are becoming increasingly rich, requiring the connection of multiple components such as camera modules and display modules. This places higher demands on the space adaptability and signal transmission capabilities of the internal flexible circuit boards. However, existing flexible circuit boards have significant shortcomings in AR devices: on the one hand, the miniaturization of devices limits the space available for flexible circuit boards, making it difficult for traditional structures to achieve a stable layout and connection of complex circuits within a limited space; on the other hand, the temples of AR devices need to be frequently folded relative to the frame, and the bending resistance of existing flexible circuit boards is insufficient, making them prone to breakage and delamination during long-term folding use. In particular, the junction between the copper foil and the dielectric layer is prone to peeling due to stress concentration, affecting the continuity of signal transmission.

[0003] Furthermore, the protective performance of existing flexible circuit boards needs improvement. In daily use and complex environments, the outer layer is easily damaged by external friction and scratches, which in turn affects the internal structure. Simultaneously, some flexible circuit boards suffer from unreasonable layer transition designs, leading to stress concentration at connections with other components of the device. This reduces the overall structural stability and lifespan, failing to meet the long-term reliable operation requirements of AR devices. These issues have collectively driven the development of folded structures for AR flexible circuit boards, possessing high bending resistance, stable signal transmission capabilities, and good protective effects. To address these problems, we propose a folded structure for AR flexible circuit boards. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides a folding structure for flexible circuit boards used in AR, thus solving the aforementioned problems.

[0005] To achieve the above-mentioned objectives, this utility model provides the following technical solution: a flexible circuit board folding structure for AR, comprising a flexible circuit board, and further comprising:

[0006] The flexible circuit board is composed of a multi-layer structure, consisting of a protective outer layer, a reinforcing layer, and a conductive layer from the outside to the inside. The layers are tightly bonded together by an acrylic adhesive through a hot-pressing process.

[0007] The protective outer layer is made of polyimide film with a thickness of 25 μm;

[0008] The reinforcing layer is made of aramid fiber fabric woven in a plain weave and has a thickness of 50 μm;

[0009] The conductive layer has a first dielectric layer, a second dielectric layer and a third dielectric layer inside, and the first dielectric layer, the second dielectric layer and the third dielectric layer are all made of polyimide material with a thickness of 50μm.

[0010] Preferably, a nano-ceramic coating is provided on the outer surface of the protective outer layer, and the nano-ceramic coating is attached by physical vapor deposition process with a thickness of 10 μm.

[0011] Preferably, the protective outer layer has a first bending area in the middle, and both ends of the protective outer layer have a first transition structure;

[0012] The thickness of the first bending region is less than that of the non-bending region, and the thickness of the first transition structure gradually decreases on the side away from the protective outer layer, and the length of the first transition structure is 5mm.

[0013] Preferably, the outer protective layer is fitted with a reinforcing layer inside, and the reinforcing layer has a second bending area in the middle and a second transition structure at both ends.

[0014] The thickness of the second bending region is less than that of the non-bending region; and the thickness of the second transition structure gradually decreases on the side away from the reinforcing layer, and the length of the second transition structure is 5 mm.

[0015] Preferably, multiple sets of parallel reinforcing ribs are fixedly installed on both sides of the reinforcing layer.

[0016] Furthermore, a conductive layer is nested inside the reinforcing layer.

[0017] Preferably, the conductive layer includes a first dielectric layer, a second dielectric layer, and a third dielectric layer, and multiple sets of copper foils are fixedly installed on the top of the first dielectric layer, the second dielectric layer, and the third dielectric layer, and the multiple sets of copper foils are arranged in parallel.

[0018] Preferably, the first dielectric layer, the second dielectric layer, and the third dielectric layer have multiple reinforcing phases chemically bonded together near the multiple sets of copper foils;

[0019] The reinforcing phases in multiple groups are nano-silica particles with a thickness of 3 μm.

[0020] Compared with the prior art, this utility model provides a flexible circuit board folding structure for AR, which has the following advantages:

[0021] 1. This AR uses a flexible circuit board folding structure with excellent bending resistance. The first bending area of ​​the protective outer layer and the second bending area of ​​the reinforcing layer have been optimized in thickness, allowing for flexible deformation with the folding of the AR device's temples to reduce stress concentration. The plain weave aramid fiber fabric of the reinforcing layer, combined with the reinforcing ribs on both sides, significantly improves mechanical strength. The transition structure design further reduces the risk of bending damage, ensuring that it is not easily broken during long-term use. It has strong structural stability. The layers are tightly bonded by hot pressing with acrylic adhesives. The second transition structure of the reinforcing layer and the first transition structure of the protective outer layer work together to reduce interlayer stress. In the conductive layer, the dielectric layer and copper foil are chemically bonded by nano-silica reinforcement phase to prevent copper foil peeling and ensure structural stability during frequent folding. It has efficient and stable signal transmission. The three dielectric layers of the conductive layer and the design of multiple sets of parallel copper foils meet the needs of complex wiring and enable simultaneous transmission of multiple signals. The parallel copper foils reduce interference, and the reinforcement phase ensures stable bonding and ensures continuous and efficient signal transmission. It has outstanding protective performance. The polyimide film of the protective outer layer has excellent insulation, and the 10μm nano-ceramic coating on the outer surface improves wear resistance and hardness, resisting friction and scratches, protecting the internal structure, and extending service life. Attached Figure Description

[0022] Figure 1 This is a three-dimensional front view schematic diagram of the present invention;

[0023] Figure 2 This is a partial cross-sectional view of the present invention;

[0024] Figure 3 This is a schematic diagram of the reinforcing layer of this utility model;

[0025] Figure 4 This is a schematic diagram of the reinforcing layer structure of this utility model;

[0026] Figure 5 This is a schematic diagram of the conductive layer of this utility model.

[0027] In the figure: 1. Protective outer layer; 2. First bending area; 3. First transition structure; 4. Reinforcing layer; 5. Second bending area; 6. Conductive layer; 7. Second transition structure; 8. Reinforcing rib; 9. First dielectric layer; 10. Second dielectric layer; 11. Third dielectric layer; 12. Copper foil; 13. Reinforcing phase. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Please see Figure 1-5 AR flexible circuit board folding structure, including flexible circuit board, also includes:

[0030] The flexible circuit board consists of a multi-layer structure, from the outside to the inside, consisting of a protective outer layer 1, a reinforcing layer 4, and a conductive layer 6, and the layers are tightly bonded together by an acrylic adhesive through a hot-pressing process.

[0031] The outer protective layer 1 is made of polyimide film with a thickness of 25 μm;

[0032] The reinforcing layer 4 is made of aramid fiber fabric using a plain weave, with a thickness of 50μm;

[0033] The conductive layer 6 has a first dielectric layer 9, a second dielectric layer 10 and a third dielectric layer 11 inside, and the first dielectric layer 9, the second dielectric layer 10 and the third dielectric layer 11 are all made of polyimide material with a thickness of 50μm.

[0034] Furthermore, a nano-ceramic coating is provided on the outer surface of the protective outer layer 1. The nano-ceramic coating is attached by physical vapor deposition and has a thickness of 10μm. The 10μm thick nano-ceramic coating on the outer surface of the protective outer layer 1 can significantly improve the surface hardness and wear resistance of the protective outer layer 1, effectively resisting friction and scratches that may occur during the use of AR devices, preventing premature damage to the protective outer layer 1, thereby extending the overall service life of the flexible circuit board. At the same time, the nano-ceramic coating has good insulation properties, which can further enhance the insulation protection capability of the protective outer layer 1.

[0035] Furthermore, a first bending area 2 is provided in the middle of the protective outer layer 1, and a first transition structure 3 is provided at both ends of the protective outer layer 1.

[0036] The thickness of the first bending region 2 is less than that of the non-bending region, and the thickness of the first transition structure 3 gradually decreases on the side away from the protective outer layer 1. The length of the first transition structure 3 is 5mm. The thickness of the first bending region 2 in the middle of the protective outer layer 1 is less than that of the non-bending region, making this region more prone to deformation when the temple of the AR device is folded, reducing stress concentration during bending, and improving the fatigue resistance of the protective outer layer 1 at the bending part. The thickness of the first transition structure 3 at both ends gradually decreases on the side away from the protective outer layer 1 and the length is 5mm. This design enables the protective outer layer 1 to achieve a smooth transition when connected to other components of the AR device, avoiding stress concentration caused by abrupt structural changes at the connection point, and ensuring the stability and reliability of the connection between the protective outer layer 1 and the device.

[0037] Furthermore, an inner reinforcing layer 4 is fitted inside the outer protective layer 1, and a second bending region 5 is provided in the middle of the reinforcing layer 4, and a second transition structure 7 is provided at both ends.

[0038] The thickness of the second bending region 5 is less than that of the non-bending region; and the thickness of the second transition structure 7 gradually decreases on the side away from the reinforcing layer 4, and the length of the second transition structure 7 is 5mm. The thickness of the second bending region 5 in the middle of the reinforcing layer 4 is less than that of the non-bending region, which can enhance the flexibility of the reinforcing layer 4 at the bending part, so that it can better adapt to the folding action of the AR device temple and reduce the risk of breakage due to frequent bending. The thickness of the second transition structure 7 at both ends gradually decreases on the side away from the reinforcing layer 4 and the length is 5mm, which can reduce the stress caused by structural abrupt changes in the connection between the reinforcing layer 4 and the protective outer layer 1 and the conductive layer 6, improve the tightness of the bonding between the reinforcing layer 4 and other layers, and thus enhance the overall structural stability of the flexible circuit board.

[0039] Furthermore, multiple sets of parallel reinforcing ribs 8 are fixedly installed on both sides of the reinforcing layer 4.

[0040] Furthermore, the reinforcing layer 4 has a conductive layer 6 nested inside, and multiple sets of parallel reinforcing ribs 8 are fixedly installed on both sides of the reinforcing layer 4, which can effectively improve the overall mechanical strength and tensile strength of the reinforcing layer 4. As an important support structure of the flexible circuit board, the increased strength of the reinforcing layer 4 can enhance the bending and tear resistance of the entire flexible circuit board, ensuring that the reinforcing layer 4 can stably play a supporting and reinforcing role during the frequent folding and use of AR devices, reducing the deformation and damage of the flexible circuit board.

[0041] Furthermore, the conductive layer 6 includes a first dielectric layer 9, a second dielectric layer 10, and a third dielectric layer 11. Multiple sets of copper foils 12 are fixedly installed on the top of the first dielectric layer 9, the second dielectric layer 10, and the third dielectric layer 11, and the multiple sets of copper foils 12 are arranged in parallel. The multiple sets of parallel copper foils 12 fixedly installed on the top of the first dielectric layer 9, the second dielectric layer 10, and the third dielectric layer 10 of the conductive layer 6 adopt a combination design of multiple dielectric layers and multiple sets of parallel copper foils 12. This design can not only meet the wiring requirements of the complex circuit of AR device and realize the simultaneous transmission of multiple signals, but also reduce the interference between signals through the parallel copper foils 12, ensuring the stability and efficiency of electrical signal transmission, and adapting to the requirements of AR device for high-precision signal transmission.

[0042] Furthermore, the first dielectric layer 9, the second dielectric layer 10, and the third dielectric layer 11 are chemically bonded to multiple sets of copper foils 12, forming multiple sets of reinforcing phases 13.

[0043] Multiple reinforcing phases 13 are 3μm thick nano-silica particles. The first dielectric layer 9, the second dielectric layer 10, and the third dielectric layer 11 are reinforced by chemically bonded 3μm thick nano-silica particles 13 near the multiple copper foils 12. This enhances the interfacial bonding between the dielectric layer and the copper foil 12, preventing the copper foil 12 from peeling off from the dielectric layer during the bending process of the flexible circuit board, and ensuring the stability of the conductive layer 6 structure. At the same time, the addition of nano-silica particles can improve the mechanical properties of the dielectric layer, help enhance the bending resistance of the entire conductive layer 6, and ensure the continuity of electrical signal transmission in AR devices.

[0044] This embodiment describes a flexible circuit board folding structure suitable for frequently used AR glasses, and its specific components are as follows:

[0045] The flexible circuit board consists of a protective outer layer 1, a reinforcing layer 4, and a conductive layer 6, arranged from the outside in. These layers are tightly bonded together using an acrylic adhesive via a hot-pressing process. The protective outer layer 1 is made of a 25μm thick polyimide film, with a 10μm nano-ceramic coating deposited on its outer surface using physical vapor deposition. The protective outer layer 1 has a first bending region 2 in its center, which is thinner than the non-bending region. It also has first transition structures 3, each 5mm long, at both ends, with the thickness of the first transition structures 3 gradually decreasing towards the side away from the protective outer layer 1. The reinforcing layer 4 is made of plain-weave aramid fiber fabric, 50μm thick, with a second bending region 5 in its center, which is thinner than the non-bending region. It also has second transition structures 7, each 5mm long, at both ends, with the thickness of the second transition structures 7 gradually decreasing towards the side away from the reinforcing layer 4. Multiple sets of parallel reinforcing ribs 8 are fixedly installed on both sides of the reinforcing layer 4. The conductive layer 6 contains a first dielectric. Layer 9, the second dielectric layer 10, and the third dielectric layer 11 are all made of 50μm thick polyimide. Multiple sets of parallel copper foils 12 are fixedly installed at the top of each layer. Near the copper foils 12, the first dielectric layer 9, the second dielectric layer 10, and the third dielectric layer 11 are chemically bonded with a 3μm thick nano-silica particle reinforcing phase 13. When the user wears the AR glasses and folds them for storage, the temples fold relative to the frame, causing the first bending area 2 of the protective outer layer 1 to deform, buffering stress. The first transition structure 3 ensures a smooth connection with the device components. The protective outer layer 1 causes the reinforcing layer 4 to move, the second bending area 5 to deform flexibly, the reinforcing rib 8 to increase support, and the second transition structure 7 to ensure the adhesion of each layer. The reinforcing layer 4 causes the conductive layer 6 to deform, the dielectric layer to deform, the copper foil 12 to stably transmit signals, and the reinforcing phase 13 to prevent the copper foil 12 from peeling off from the dielectric layer, achieving stable folding and signal transmission under high-frequency use.

[0046] Instructions for use

[0047] When the temples of the AR device fold relative to the frame, the protective outer layer 1 moves first. The first bending area 2 in the middle of the protective outer layer 1, being thinner than the non-bending area, deforms more easily with the folding motion, buffering the stress generated by the folding through its flexible deformation. Simultaneously, the first transition structures 3 at both ends gradually thin away from the protective outer layer 1, achieving a smooth transition at the connection points with other components of the device, preventing stress concentration that could damage the protective outer layer 1 and ensuring its protective function for the internal structure. A 10μm nano-ceramic coating, applied to the outer surface of the protective outer layer 1 using physical vapor deposition, further enhances its protective function during folding and... In daily use, thanks to its high hardness and wear resistance, it resists external friction and scratches, further protecting the outer protective layer 1 and the internal structure. The movement of the outer protective layer 1 synchronously drives the movement of the internally sleeved reinforcing layer 4. The second bending area 5 in the middle of the reinforcing layer 4, being thinner than the non-bending area, deforms flexibly with the folding action. The reinforcing layer 4 is made of plain-weave aramid fiber fabric, which has high mechanical strength. Combined with multiple sets of parallel reinforcing ribs 8 fixedly installed on both sides, it greatly improves the tensile and tear resistance of the reinforcing layer 4, providing stable support for the entire flexible circuit board during folding. At the same time, the second transition at both ends of the reinforcing layer 4... Structure 7 achieves smooth coordination with the protective outer layer 1 and conductive layer 6 during movement, reducing stress caused by structural abrupt changes and enhancing the tightness of the bonding between layers; the movement of the reinforcing layer 4 drives the movement of the internally nested conductive layer 6. The first dielectric layer 9, second dielectric layer 10, and third dielectric layer 11 in the conductive layer 6 are all made of polyimide, possessing good flexibility and adapting to deformation during folding. Multiple sets of parallel-arranged copper foils 12 are fixedly installed at their tops, maintaining a stable signal transmission path during folding, meeting the simultaneous transmission requirements of multiple signals in the complex circuitry of AR devices, and the parallel arrangement reduces signal interference; the first dielectric layer... 9. The second dielectric layer 10 and the third dielectric layer 11 are reinforced with chemically bonded 3μm nano-silica particles 13 near the copper foil 12, which enhances the interfacial bonding between the dielectric layer and the copper foil 12, prevents the copper foil 12 from peeling off from the dielectric layer during folding, ensures the structural stability of the conductive layer 6, and ensures the continuity of electrical signal transmission. Throughout the process, the protective outer layer 1, the reinforcing layer 4, and the conductive layer 6 are tightly bonded together by hot pressing with acrylic adhesive. The movement of each layer is synchronized and the stress is uniform. While enabling the flexible folding of the AR device's temple, the bending resistance and signal transmission stability of the flexible circuit board are guaranteed, thus extending the service life of the AR device.

[0048] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A flexible circuit board folding structure for AR, comprising a flexible circuit board, characterized in that, Also includes: The flexible circuit board is composed of a multi-layer structure, consisting of a protective outer layer (1), a reinforcing layer (4), and a conductive layer (6) from the outside to the inside. The layers are tightly bonded together by an acrylic adhesive through a hot-pressing process. The protective outer layer (1) is made of polyimide film with a thickness of 25 μm; The reinforcing layer (4) is made of aramid fiber fabric woven in a plain weave and has a thickness of 50 μm; The conductive layer (6) is provided with a first dielectric layer (9), a second dielectric layer (10) and a third dielectric layer (11), and the first dielectric layer (9), the second dielectric layer (10) and the third dielectric layer (11) are all made of polyimide material with a thickness of 50μm.

2. The flexible circuit board folding structure for AR according to claim 1, characterized in that: The outer surface of the protective outer layer (1) is provided with a nano-ceramic coating, and the nano-ceramic coating is attached by physical vapor deposition process with a thickness of 10 μm.

3. The flexible circuit board folding structure for AR according to claim 1, characterized in that: The protective outer layer (1) has a first bending area (2) in the middle, and the protective outer layer (1) has a first transition structure (3) at both ends; The thickness of the first bending region (2) is less than that of the non-bending region, and the thickness of the first transition structure (3) gradually decreases on the side away from the protective outer layer (1), and the length of the first transition structure (3) is 5 mm.

4. The flexible circuit board folding structure for AR according to claim 1, characterized in that: The protective outer layer (1) is fitted with an inner reinforcing layer (4), and the reinforcing layer (4) has a second bending area (5) in the middle and a second transition structure (7) at both ends. The thickness of the second bending region (5) is less than that of the non-bending region; and the thickness of the second transition structure (7) gradually decreases on the side away from the reinforcing layer (4), and the length of the second transition structure (7) is 5 mm.

5. The flexible circuit board folding structure for AR according to claim 1, characterized in that: Multiple sets of parallel reinforcing ribs (8) are fixedly installed on both sides of the reinforcing layer (4); Furthermore, the reinforcing layer (4) is internally fitted with a conductive layer (6).

6. The flexible circuit board folding structure for AR according to claim 1, characterized in that: The conductive layer (6) includes a first dielectric layer (9), a second dielectric layer (10) and a third dielectric layer (11). Multiple sets of copper foils (12) are fixedly installed on the top of the first dielectric layer (9), the second dielectric layer (10) and the third dielectric layer (11), and the multiple sets of copper foils (12) are arranged in parallel.

7. The flexible circuit board folding structure for AR according to claim 6, characterized in that: The first dielectric layer (9), the second dielectric layer (10), and the third dielectric layer (11) are chemically bonded to multiple sets of reinforcing phases (13) near the multiple sets of copper foils (12); The multiple sets of the reinforcing phase (13) are nano-silica particles with a thickness of 3 μm.

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