Optical fiber array assembly, signal receiving structure and optical module

Abstract

An optical fiber array assembly, a signal receiving structure and an optical module. The optical fiber array assembly comprises an optical fiber array module (1) and a lens module (2) adapted to the optical fiber array module (1), wherein the optical fiber array module (1) comprises a base (11) and at least two optical fibers (14) arranged in an array on one side of the base (11), an end part of each optical fiber (14) is formed as a bevel (141), the lens module (2) is arranged on the other side of the base (11) and corresponds to the end parts of the optical fibers (14), optical signals transmitted by the optical fibers (14) are reflected into the base (11) via the bevels (141), the optical signals pass through the base (11) and then are emitted into the lens module (2), and the lens module (2) is used for converging the optical signals on a transceiver chip (4). On the one hand, a light spot of a smaller size can be obtained, such that not only high coupling efficiency is achieved, but also a position window of the optical fiber array module in which all of channels achieve high coupling efficiency is broader, thereby effectively reducing the process difficulty; on the other hand, the probability of a collision between the optical fiber array module and the transceiver chip is greatly reduced, thereby effectively improving the product yield.

Description

A fiber optic array assembly, a signal receiving structure, and an optical module Technical Field

[0001] This invention relates to the field of optical communication equipment technology, specifically to an optical fiber array assembly, a signal receiving structure, and an optical module. Background Technology

[0002] Optical modules are crucial components in optical communication technology, primarily used for converting between photoelectric and electrical signals. Existing optical modules typically consist of a base, top cover, PCBA board (circuit board), fiber optic interface, receiver (RX), and / or transmitter (TX). The receiver primarily performs photoelectric conversion, while the transmitter performs electro-optic conversion. Optical modules utilize a COB (chip-on-board) packaging process, which aims to optically couple relevant components to the PCBA board, ultimately achieving the photoelectric / electro-optical conversion of optical signals.

[0003] In the receiving section (RX) of existing optical modules, optical signal transmission is generally achieved by directly coupling the optical output from the optical fiber to the receiving chip (such as a photodetector (PD)). The specific implementation structure is shown in Figures 1 and 2. The receiving optical device uses an optical fiber array module, and the receiving chip uses a photodetector. The optical fiber array module includes a first clamping part (base), a second clamping part (cover plate), and at least two optical fibers. Each optical fiber is arranged in an array and clamped between the first clamping part and the second clamping part to fix the optical fiber. As shown in Figure 1, the second clamping part is not covered near the end of the optical fiber, so that the photodetector can be closer to the optical fiber. The ends of the first clamping part and the optical fiber are processed into total internal reflection slopes, as shown in Figure 1, so as to change the transmission direction of the optical signal by using the total internal reflection slopes. The photodetector and the second clamping part are set on the same side of the first clamping part, and the photodetector corresponds to the end of the optical fiber, as shown in Figures 1 and 2, so that the optical signal reflected by the total internal reflection slope can be smoothly coupled into the photodetector.

[0004] Table 1. Relationship between spot diameter and spacing between the photodetector and fiber array module outlines.

[0005] However, the existing design has the following drawbacks: First, since the light emitted from the optical fiber is divergent, to achieve high efficiency in coupling to the photodetector (the diameter of a conventional high-speed PD is 16µm or smaller), the diameter of the light spot hitting the photodetector needs to be less than 16µm. As shown in Table 1, it can be seen from Table 1 that the smaller the spacing between the photodetector and the optical fiber in the fiber array module, the smaller the diameter of the light spot hitting the photodetector. The photodetector needs to be very close to the outline of the optical fiber in the fiber array module to ensure that the light spot diameter is less than 16µm. This requires clear image recognition to determine and control the position of the fiber array module during coupling, which makes this design very demanding on the process. Moreover, in the actual assembly process, even with the assistance of image recognition, the fiber array module is still very easy to collide with the photodetector, causing damage or even destruction to the optical fiber and / or the photodetector, which greatly affects the product yield.

[0006] Secondly, in practice, the light spot size of the beam hitting the photodetector is relatively large, resulting in low coupling efficiency. In addition, there are various manufacturing tolerances in the fiber array module, which makes the coupling position window of the fiber array module that achieves high coupling efficiency for all channels narrow, further increasing the difficulty of the process. Summary of the Invention

[0007] The first aspect of this invention addresses the aforementioned technical problems by providing a fiber optic array assembly. This assembly offers advantages such as simple manufacturing process and higher coupling efficiency. It not only widens the coupling position window of the fiber optic array module but also significantly reduces the probability of collisions between the fiber optic array module and photoelectric detectors, effectively improving product yield. The main concept is as follows:

[0008] A fiber optic array assembly includes a fiber optic array module and a lens module adapted to the fiber optic array module. The fiber optic array module includes a base and at least two optical fibers arranged in an array on one side of the base, with the ends of the optical fibers having beveled structures. The lens module is disposed on the other side of the base and corresponds to the ends of the optical fibers. The optical signal transmitted by the optical fibers is reflected into the base by the beveled structures, and the optical signal passes through the base and enters the lens module. The lens module is used to converge the optical signal onto a light-receiving chip. In this design, the end of the optical fiber is constructed as a bevel to form a total internal reflection surface, which alters the transmission direction of the optical signal. The optical fiber is positioned on one side of the base, and the lens module on the other side, with the lens module aligned with the end of the corresponding optical fiber. This arrangement allows the optical fiber and lens module to be located on opposite sides of the base and work in tandem. Firstly, the light beam reflected from the total internal reflection surface can enter the base and, after passing through it, enter the lens module, achieving smooth and stable optical signal transmission. Secondly, because the base separates the optical fiber and the lens module, the thickness of the base can be controlled or adjusted during production to accommodate lens modules with different focal lengths, thus meeting the needs of lenses with varying focal lengths. The application requirements of the group; the focusing speed and focusing distance of the light beam on the output side of the lens module can also be controlled or adjusted by controlling or changing the thickness of the base. This not only minimizes the distance between the lens module and the light receiving chip while ensuring the beam diameter, which is beneficial to reducing the overall volume of the signal receiving structure and optical module, but also obtains a smaller beam diameter. This can significantly improve coupling efficiency and make the coupling position window of the fiber array module with high coupling efficiency in all channels wider, greatly reducing the difficulty of the process; thirdly, since the base is between the optical fiber and the lens module, it can prevent foreign objects from colliding with the fragile optical fiber during the manufacturing process, thus protecting the optical fiber and improving the product yield. By configuring a lens module to focus the light beam, the beam gradually converges after passing through the lens module and eventually converges onto the receiving chip. This allows for sufficient spacing between the lens module and the receiving chip during assembly. Firstly, the receiving chip does not need to directly contact the lens module, and it is kept away from the optical fiber, significantly reducing the probability of collisions between the fiber array module and the photoelectric detector, effectively improving product yield. Secondly, during assembly, there is no need for precise image recognition to determine and control the position of the fiber array module, simplifying the process. Furthermore, the lens module focuses the beam onto the receiving chip, greatly reducing the diameter of the light spot hitting the chip. This not only further improves coupling efficiency but also allows for a wider coupling position window for all channels of the fiber array module to achieve high coupling efficiency, effectively reducing process complexity.

[0009] Preferably, the lens module is connected to the base using adhesive. In this solution, connecting the lens module and the base with adhesive not only stably fixes the lens module to the base, ensuring that the spacing between the lens module and the optical fiber does not change, which is beneficial for ensuring stable transmission of optical signals, but also eliminates the gap between the lens module and the base, avoiding the problem of optical signal transmittance loss due to the interface between the optical fiber array module and the air, thus improving the transmittance of optical signals.

[0010] Preferably, the adhesive used is a refractive index matching adhesive.

[0011] Preferably, the thickness of the base is 0.1 mm to 1.2 mm. This is beneficial for obtaining a smaller diameter light spot with a smaller overall volume and can effectively improve coupling efficiency.

[0012] A second aspect of this invention addresses the problem of improving light transmission efficiency. Further, the surface of the lens module facing the base is the light-incoming surface, and a first anti-reflective film is provided on this surface. By providing the first anti-reflective film on the light-incoming surface of the lens module, and positioning it precisely between the adhesive and the lens module, the problem of significantly reduced light transmission efficiency due to the large difference in refractive index between the adhesive and the lens module is solved, effectively improving both the transmittance and light transmission efficiency of the optical signal.

[0013] A third aspect of this invention addresses the problem of further improving light transmission efficiency. Specifically, the surface of the lens module facing away from the base is the light-emitting surface, and a second anti-reflective film is provided on this surface. By providing the second anti-reflective film on the light-emitting surface of the lens module, which is positioned precisely between the lens module and the air, the problem of significantly reduced light transmission efficiency due to the large difference in refractive index between the lens module and air is solved, effectively improving both the transmittance and light transmission efficiency of the optical signal.

[0014] To further improve light transmission efficiency, a third anti-reflective film is applied to the surface of the base facing the lens module. By placing this third anti-reflective film on the base surface, positioned precisely between the base and the adhesive, the problem of significantly reduced light transmission efficiency caused by the large difference in refractive index between the base and the adhesive is solved, effectively improving both light signal transmittance and light transmission efficiency.

[0015] The fourth aspect of this invention addresses the issues of reducing size and cost. Furthermore, the lens module employs a silicon lens. Silicon lenses have a high refractive index, making it easier to focus the light beam, thereby shortening the focal length of the lens module. This allows the entire fiber optic array module to be made shorter vertically (longitudinally), ensuring the overall height of the fiber optic array module is not excessive. This not only helps reduce size but also lowers costs.

[0016] The fifth aspect of this invention addresses the problem of fiber edge breakage leading to product yield loss during the manufacturing and use of existing fiber array modules. Furthermore, the fiber array module includes a cover plate connected to a base, which clamps at least both sides of the fiber end between the cover plate and the base. This not only provides a simpler, more stable, and reliable way to constrain the fiber, but also protects both sides of the fiber end by clamping them internally, effectively protecting the fragile ends of the fiber. This significantly reduces the risk of fiber edge breakage during manufacturing and use, improving product yield, and effectively prevents the fiber from being damaged by impacts, thus extending its service life.

[0017] Furthermore, the cover plate or base has at least two grooves for accommodating optical fibers, with each optical fiber disposed within its respective groove, and the grooves filled with refractive index matching adhesive. On one hand, the refractive index matching adhesive can be used to more stably and reliably fix the optical fibers; on the other hand, the refractive index matching adhesive can fill the gaps within the grooves, and because the refractive index of the adhesive can match that of the optical fiber and the base, the loss of optical signal from the optical fiber into the base is reduced, resulting in higher transmittance.

[0018] Preferably, the groove is a V-shaped groove.

[0019] Preferably, one end of the base is constructed as an inclined surface; one end of the cover plate is constructed as an inclined surface.

[0020] The sixth aspect of this invention addresses the problem of ensuring and improving coupling efficiency. Further, the fiber array module includes a spacer block, with the base connected to the spacer block. The spacer block and the lens module are located on the same side of the base, and the spacing between the lens module and the light-receiving chip is controlled by the spacer block. By configuring the spacer block and placing it and the lens module on the same side of the base, not only can the spacer block stably support the base, but the spacing between the lens module and the light-receiving chip can also be controlled and ensured by controlling the thickness of the spacer block. This ensures that the spacing between the lens module and the light-receiving chip meets the design requirements, resulting in a smaller light spot diameter and thus facilitating higher coupling efficiency.

[0021] Preferably, the thickness of the pad is 0.3mm to 2.15mm. This ensures that the spacing between the lens module and the light-receiving chip meets the design requirements while allowing for a smaller light spot diameter, which is more conducive to achieving higher coupling efficiency.

[0022] Preferably, the pad is attached to the base by adhesive.

[0023] A signal receiving structure includes the aforementioned fiber optic array assembly, a light-receiving chip, and a supporting component. The light-receiving chip is disposed on the supporting component and corresponds to the lens module, with a gap between the lens module and the light-receiving chip. In this solution, by aligning the light-receiving chip with the lens module and reserving a gap between the lens module and the light-receiving chip to match the focal length of the lens module, the light beam can gradually converge on the light-receiving chip after passing through the lens module. This significantly reduces the diameter of the light spot hitting the light-receiving chip, further improving coupling efficiency and allowing for a wider coupling position window for the fiber optic array module to achieve high coupling efficiency across all channels, effectively reducing manufacturing complexity. Simultaneously, during assembly, on the one hand, the light-receiving chip does not need to directly contact the lens module, and the light-receiving chip is kept away from the optical fiber, thus greatly reducing the probability of collision between the fiber optic array module and the photoelectric detector, effectively improving product yield. On the other hand, it eliminates the need for clear image recognition to determine and control the position of the fiber optic array module, simplifying the process.

[0024] Preferably, the distance between the lens module and the light-receiving chip is 0.1mm to 2mm. This is beneficial for achieving the above-mentioned technical effects.

[0025] Furthermore, the fiber optic array assembly also includes a spacer block, with the base disposed on the spacer block and the spacer block disposed on the support component. The spacer block controls the spacing between the lens module and the light-receiving chip. In this solution, the light-receiving chip is disposed on the support component, and the base of the fiber optic array assembly is also disposed on the support component via the spacer block. The lens module in the fiber optic array assembly corresponds to the light-receiving chip. This not only allows the fiber optic array assembly to be stably supported by the spacer block, but also allows the spacing between the lens module and the light-receiving chip to be controlled and guaranteed by controlling the thickness of the spacer block. This ensures that the spacing between the lens module and the light-receiving chip meets the design requirements, resulting in a smaller light spot size focused onto the light-receiving chip by the lens module, thereby facilitating higher coupling efficiency.

[0026] Preferably, the light-receiving chip is a photodetector.

[0027] Preferably, the supporting component is a PCB board or a substrate.

[0028] An optical module includes the fiber array assembly or the optical signal receiving structure.

[0029] Furthermore, it also includes a housing, which has an assembly space, and the fiber array assembly or the optical signal receiving structure is disposed in the assembly space.

[0030] Preferably, the housing includes a base and a top plate, the top plate being detachably disposed on the base, and the assembly space being formed between the top plate and the base.

[0031] Preferably, it also includes a fiber optic interface, which is located at one end of the housing. The fiber optic array assembly is connected to the fiber optic interface via an optical fiber, so that external optical signals can be transmitted to the receiving chip inside the optical module through the fiber optic interface.

[0032] Compared with the prior art, the fiber array assembly, signal receiving structure and optical module provided by the present invention can, on the one hand, obtain a smaller light spot, which not only has higher coupling efficiency, but also makes the coupling position window of the fiber array module with high coupling efficiency in all channels wider, effectively reducing the difficulty of the process; on the other hand, it greatly reduces the probability of collision between the fiber array module and the light receiving chip, and effectively improves the product yield. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 is a schematic diagram of the structure of an existing fiber optic array module.

[0035] Figure 2 is a schematic diagram of an existing optical fiber coupling scheme.

[0036] Figure 3 is a schematic diagram of the structure of a fiber optic array assembly provided in Embodiment 1 of the present invention.

[0037] Figure 4 is a three-dimensional structural schematic diagram of an optical fiber array assembly provided in Embodiment 1 of the present invention.

[0038] Figure 5 is a three-dimensional structural schematic diagram of another fiber optic array component provided in Embodiment 1 of the present invention.

[0039] Figure 6 is a schematic diagram of the structure when using the fiber array assembly shown in Figure 3 for fiber coupling.

[0040] Figure 7 is a partial structural schematic diagram of an optical fiber array assembly provided in Embodiment 2 of the present invention.

[0041] Figure 8 is a partial structural schematic diagram of another fiber optic array component provided in Embodiment 2 of the present invention.

[0042] Figure 9 is a schematic diagram of a signal receiving structure provided in Embodiment 3 of the present invention.

[0043] Figure 10 is a comparison of the effects of the coupling scheme provided by the present invention and existing coupling schemes.

[0044] The markings in the diagram are as follows: Fiber optic array module 1, base 11, cover plate 12, groove 13, fiber optic cable 14, inclined surface 141, third anti-reflective film 15; lens module 2, spherical surface 21, first anti-reflective film 22, second anti-reflective film 23; pad 3; light receiving chip 4; adhesive 5; support component 6. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0046] Example 1

[0047] This embodiment provides a fiber optic array assembly, including a fiber optic array module 1 and a lens module 2 adapted to the fiber optic array module 1, as shown in Figures 2-5. The fiber optic array module 1 includes a base 11 and optical fibers 14. In implementation, the number of optical fibers 14 can be determined according to actual needs, and can be one, two, three, etc. In a preferred embodiment, the fiber optic array module 1 is configured with at least two optical fibers 14, and each optical fiber 14 is arranged in an array on one side of the base 11. For example, in this embodiment, the fiber optic array module 1 is configured with four optical fibers 14, as shown in Figures 4 and 5, and the four optical fibers 14 are respectively arranged at array intervals on the upper side of the base 11.

[0048] As shown in Figures 3-5, the ends of each optical fiber 14 are constructed as inclined surfaces 141. The angle of inclination of the inclined surfaces 141 can adopt existing technology so that a total internal reflection surface is formed through the inclined surfaces 141 at the ends of the optical fibers 14, thereby changing the transmission direction of the optical signal. In implementation, the optical fibers 14 in the optical fiber array module 1 have various implementation methods. For example, in one implementation, the optical fibers 14 can be fixed to the upper surface of the base 11 with adhesive. In another implementation, the upper surface of the base 11 is constructed with grooves 13 for accommodating the optical fibers 14. The number of grooves 13 is the same as the number of optical fibers 14, and each optical fiber 14 is respectively disposed in each groove 13, as shown in Figures 4 and 5, and can be fixed with adhesive. Because the front end of the optical fiber 14 in the optical fiber array module 1 is thinned into a total reflection bevel 141, it is very fragile, which makes it easy for the optical fiber 14 to chip during manufacturing and use, resulting in a loss of yield. Therefore, in a further embodiment, the optical fiber array module 1 also includes a cover plate 12 adapted to the base 11. The cover plate 12 is connected to the base 11. For example, the cover plate 12 can be glued to the base 11. The cover plate 12 at least clamps both sides of the end of the optical fiber 14 between the cover plate 12 and the base 11. For example, as shown in Figures 4 and 5, the entire front end of the optical fiber 14 is clamped between the cover plate 12 and the base 11, so that both sides of the end of the optical fiber 14 can be clamped inside, so that both the top and bottom sides of the optical fiber 14 are protected. In particular, it can effectively protect the fragile end of the optical fiber 14. This can not only greatly reduce the risk of chipping of the optical fiber 14 during manufacturing and use, and effectively improve the product yield, but also effectively prevent the optical fiber 14 from being damaged or broken, which is conducive to improving the service life. For example, in another preferred embodiment, a cover plate 12 adapted to the base 11 is also included. The cover plate 12 is constructed with grooves 13 for accommodating optical fibers 14, as shown in FIG5. The number of grooves 13 is the same as the number of optical fibers 14. Each optical fiber 14 is respectively disposed in each groove 13. The cover plate 12 is connected to the base 11, thereby clamping the optical fibers 14 between the cover plate 12 and the base 11, achieving the purpose of more convenient, stable and reliable constraint of the optical fibers 14.

[0049] In implementation, the groove 13 can preferably be filled with refractive index matching adhesive. On the one hand, the refractive index matching adhesive can be used to fix the optical fiber 14 more stably and reliably; on the other hand, the refractive index matching adhesive can fill the gaps in the groove 13, and since the refractive index of the refractive index matching adhesive can match the optical fiber 14 and the base 11, the loss of optical signal from the optical fiber 14 to the base 11 is smaller, and the transmittance is higher. In implementation, the groove 13 can preferably be a V-groove, as shown in Figures 4 and 5, and the portion of the optical fiber 14 sandwiched between the cover plate 12 and the base 11 can include a fiber core and a cladding covering the fiber core. In implementation, the base 11 can preferably be constructed as a plate-like structure or a similar plate-like structure; the cover plate 12 can also preferably be constructed as a plate-like structure or a similar plate-like structure, as shown in Figures 3-5. Both the base 11 and the cover plate 12 can preferably be made of glass.

[0050] During manufacturing, one end of the base 11 can also be constructed as a slope 141, and one end of the cover plate 12 can also be constructed as a slope 141, as shown in Figures 3-5. The inclination angle of each slope 141 can be the same.

[0051] As shown in Figures 3-5, the lens module 2 is located on the other side of the base 11 and corresponds to the end of the optical fiber 14. That is, the lens module 2 and the optical fiber 14 are respectively located on both sides of the base 11. The number and position of the lenses in the lens module 2 are adapted to each optical fiber 14. The optical signal transmitted by the optical fiber 14 is reflected by the inclined surface 141 at the end of the optical fiber 14 and enters the base 11. After passing through the base 11, the optical signal enters the lens module 2. Specifically, the optical signal output by each optical fiber 14 can be injected into each lens, as shown in Figure 6. The lens module 2 has a focusing function. The lens module 2 is mainly used to converge the optical signal onto the light receiving chip 4. In this embodiment, the optical fiber 14 and the lens module 2 are located on both sides of the base 11 and cooperate with each other. During production and manufacturing, the thickness of the base 11 can be controlled or changed to adapt to lens modules 2 with different focal lengths, so as to meet the application requirements of lens modules 2 with different focal lengths. At the same time, the focusing speed and focusing distance of the light beam on the output side of the lens module 2 can also be controlled or adjusted by controlling or changing the thickness of the base 11. This is because if the base 11 is too thin, the distance between the optical fiber 14 and the lens module 2 will be too close, and the focusing distance of the light beam on the output side of the lens module 2 will be greatly increased, which will lead to a significant increase in the size of the entire fiber array assembly and optical module, or make it impossible to achieve the desired size within the predetermined size range. To obtain a smaller light spot size, if the base 11 is too thick, the distance between the optical fiber 14 and the lens module 2 will be too large, which will also greatly increase the size of the entire fiber array assembly and optical module. Therefore, it is necessary to set the thickness of the base 11 reasonably. Usually, the thickness of the base 11 can be configured according to the focal length of the lens module 2. This not only minimizes the distance between the lens module 2 and the light receiving chip 4 while ensuring the light spot diameter, which is beneficial to reducing the overall volume of the signal receiving structure and optical module, but also obtains a smaller light spot diameter. This can significantly improve the coupling efficiency and make the coupling position window of the fiber array module 1 with high coupling efficiency for all channels wider, greatly reducing the manufacturing difficulty. In practical applications, since the light beam gradually converges after passing through the lens module 2 and eventually converges on the light-receiving chip 4, sufficient spacing can be reserved between the lens module 2 and the light-receiving chip 4 during assembly. On the one hand, the light-receiving chip 4 does not need to directly contact the lens module 2, and the light-receiving chip 4 is also far away from the optical fiber 14, thereby greatly reducing the probability of collision between the fiber array module 1 and the photoelectric detector, and effectively improving the product yield. On the other hand, during the assembly process, there is no need to determine and control the position of the fiber array module 1 through clear image recognition, making the process simpler. In addition, the lens module 2 focuses the light beam onto the light-receiving chip 4, which can greatly reduce the diameter of the light spot hitting the light-receiving chip 4. This not only further improves the coupling efficiency, but also makes the coupling position window of the fiber array module 1, which achieves high coupling efficiency in all channels, wider, effectively reducing the difficulty of the process. For a related explanation of the coupling position window of the fiber array module 1, please refer to Example 3, which will not be repeated here.

[0052] During implementation, the thickness of the base 11 can preferably be 0.1mm to 1.2mm, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, etc., which is conducive to achieving better results.

[0053] In implementation, each lens in the lens module 2 can preferably be a spherical lens 21. The lens module 2 can be a one-piece molded component, as shown in Figures 3 and 6. That is, the lens module 2 has a convex surface 21. The spherical surface 21 is used for light emission. The material of the lens module 2 can be determined according to actual needs. In this embodiment, the lens module 2 uses a silicon lens. The silicon lens has a high refractive index, which makes it easier for the light beam to be focused, thereby shortening the focal length of the lens module 2. As a result, the entire fiber array module 1 can be made shorter in the vertical direction (longitudinal direction). The overall height of the fiber array module 1 will not be too high, which is not only conducive to reducing the volume, but also to lowering the cost.

[0054] In existing technologies, the fiber optic array module 1 is directly coupled to the photodetector, as shown in Figure 2. A gap exists between the fiber optic array module 1 and the photodetector, resulting in a loss of approximately 4% in optical signal transmittance due to the interface between the fiber optic array module 1 and the air. In this embodiment, the lens module 2 can be connected to the base 11 using adhesive 5, as shown in Figures 3 and 6. This not only stably fixes the lens module 2 to the base 11, ensuring that the distance between the lens module 2 and the fiber optic cable 14 remains unchanged, thus facilitating stable optical signal transmission, but also eliminates the gap between the lens module 2 and the base 11 using adhesive 5, avoiding the transmittance loss caused by the interface between the fiber optic array module 1 and the air, thereby improving optical signal transmittance. In implementation, refractive index matching adhesive can be preferentially used as the adhesive 5.

[0055] Example 2

[0056] Since the space between the base 11 and the lens module 2 is filled with adhesive 5, when there is a large difference between the refractive index of adhesive 5 and the refractive index of the lens module 2, the light transmission efficiency at the interface between adhesive 5 and lens module 2 will be greatly reduced. Especially when the lens module 2 is made of silicon, the refractive index of the lens module 2 is large, and the difference between the refractive index of adhesive 5 and the refractive index of the lens module 2 is even greater, which seriously affects the light transmission efficiency. To solve this technical problem, the main difference between this embodiment 2 and the above embodiment 1 is that in the fiber array assembly provided in this embodiment, the surface of the lens module 2 facing the base 11 is the light-inlet surface, and the light-inlet surface is provided with a first anti-reflection film 22, as shown in Figure 7. By providing the first anti-reflection film 22 on the light-inlet surface of the lens module 2, the first anti-reflection film 22 is located exactly between adhesive 5 and lens module 2. The first anti-reflection film 22 is used to solve the problem of greatly reduced light transmission efficiency caused by the large difference in refractive index between adhesive 5 and lens module 2, which can effectively improve the transmittance and light transmission efficiency of optical signals.

[0057] Similarly, when there is a large difference between the refractive index of lens module 2 and the refractive index of air, the light transmission efficiency at the interface between lens module 2 and air will be greatly reduced. Especially when lens module 2 is made of silicon, the refractive index of lens module 2 is large, and the difference between the refractive index of air and the refractive index of lens module 2 is even greater, which seriously affects the light transmission efficiency. To solve this technical problem, in a further embodiment, the surface of lens module 2 that faces away from the base 11 and is used for light emission is the light emission surface (including the spherical surface 21). The light emission surface is provided with a second anti-reflection film 23, as shown in Figure 7. By providing the second anti-reflection film 23 on the light emission surface of lens module 2, the second anti-reflection film 23 is located exactly between lens module 2 and air. Thus, the second anti-reflection film 23 can be used to solve the problem of greatly reduced light transmission efficiency caused by the large difference in refractive index between lens module 2 and air, and can further improve the transmittance and light transmission efficiency of light signals.

[0058] In a further embodiment, a third anti-reflective film 15 can be provided on the surface of the base 11 facing the lens module 2, as shown in FIG8. By providing the third anti-reflective film 15 on the surface of the base 11, the third anti-reflective film 15 is located exactly between the base 11 and the adhesive 5. Thus, the third anti-reflective film 15 can be used to solve the problem of the large difference in refractive index between the base 11 and the adhesive 5, which leads to a significant reduction in light transmission efficiency. This can further improve the transmittance and light transmission efficiency of the light signal.

[0059] Example 3

[0060] This embodiment provides a signal receiving structure, mainly used to convert optical signals into electrical signals. In this embodiment, the signal receiving structure includes a light-receiving chip 4, a supporting component 6, and the fiber optic array assembly as in Embodiment 1 or 2. The light-receiving chip 4 is mainly used to receive optical signals and convert them into corresponding electrical signals. As shown in Figure 9, the light-receiving chip 4 is disposed on the supporting component 6, located below and corresponding to the lens module 2. As shown in Figure 9, there is a gap between the lens module 2 and the light-receiving chip 4, and this gap can be much larger than the gap between the fiber optic array module 1 and the light-receiving chip 4 in the prior art. This allows the light beam to gradually converge on the light-receiving chip 4 after passing through the lens module 2, which can greatly reduce the diameter of the light spot hitting the light-receiving chip 4. This not only further improves the coupling efficiency, but also makes the coupling position window of the fiber optic array module 1, which achieves high coupling efficiency in all channels, wider, effectively reducing the manufacturing difficulty. Meanwhile, during the assembly process, on the one hand, the light-collecting chip 4 does not need to directly contact the lens module 2, and the light-collecting chip 4 is also far away from the optical fiber 14, which greatly reduces the probability of the optical fiber array module 1 colliding with the photoelectric detector and effectively improves the product yield; on the other hand, there is no need to determine and control the position of the optical fiber array module 1 through clear image recognition, which simplifies the process.

[0061] During implementation, the spacing between the lens module 2 and the optical fiber 14 can be preferentially controlled to be 0.1mm to 2mm. For example, 0.3mm, 0.36mm, 0.4mm, 0.5mm, 0.6mm, etc. can be preferred to achieve better results.

[0062] To facilitate precise control of the spacing between the lens module 2 and the light-receiving chip 4, the fiber optic array assembly also includes a spacer 3, as shown in Figure 9. The spacer 3 is positioned below the base 11, which can be glued to it. The spacer 3 can be placed on the support component 6. This spacer 3 not only provides stable support for the fiber optic array assembly but also ensures that both the fiber optic array assembly and the light-receiving chip 4 are mounted on the same support component 6, leaving the lens module 2 suspended (as shown in Figure 9) away from the light-receiving chip 4 below. During implementation, the spacer 3 has a predetermined thickness. Controlling the thickness of the spacer 3 controls and ensures that the spacing between the lens module 2 and the light-receiving chip 4 meets design requirements. This results in a smaller light spot size focused onto the light-receiving chip 4 by the lens module 2, thereby improving coupling efficiency.

[0063] During implementation, the thickness of the pad 3 can preferably be 0.3mm to 2.15mm, for example, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, etc., which is conducive to achieving better results.

[0064] In this invention, the coupling position window of the fiber array module 1 refers to the maximum lateral positional deviation (which can be understood as coaxiality, referring to the dashed line in Figure 9) between the fiber array module 1 (lens module 2) and the light-receiving chip 4 that is allowed when assembling the fiber array module 1 or the light-receiving chip 4. It can be understood that the greater the lateral positional deviation between the fiber array module 1 and the light-receiving chip 4, that is, the less aligned the lens module 2 and the light-receiving chip 4 are, the lower the coupling efficiency. Therefore, the coupling position window of the fiber array module 1 that enables all channels to achieve high coupling efficiency refers to the maximum lateral positional deviation between the fiber array module 1 (lens module 2) and the light-receiving chip 4 that is allowed while ensuring that all channels achieve high coupling efficiency. For example, as shown in Figure 10, a comparison is made between the coupling scheme provided by this invention and existing coupling schemes. It can be seen that: First, the theoretical simulation maximum coupling efficiency of existing coupling schemes is only about 90%, while the coupling efficiency of the coupling scheme provided by this invention is significantly higher, approaching 100% in theoretical simulations. Second, in existing coupling schemes, while ensuring a high coupling efficiency above 90%, the maximum allowable lateral position deviation between the fiber array module 1 and the receiving chip 4 is ±1µm; as shown in Figure 10, the coupling scheme provided by this invention, while ensuring a high coupling efficiency above 95%, allows a maximum allowable lateral position deviation between the fiber array module 1 and the receiving chip 4 of ±4µm, and while ensuring a high coupling efficiency close to 100%, allows a maximum allowable lateral position deviation of ±1.5µm, making the coupling position window of the fiber array module 1, which achieves high coupling efficiency for all channels, significantly wider.

[0065] In implementation, the support component 6 can preferably adopt a plate-like structure, as shown in Figure 9. In this embodiment, the support component 6 can be a PCB board or a substrate, etc.; the light receiving chip 4 can be a photodetector to collect light signals.

[0066] In a more complete solution, this signal receiving structure also includes a TIA chip. The light receiving chip 4 can be connected to the TIA chip, and the TIA chip can also be located on the supporting component 6.

[0067] Example 4

[0068] This embodiment provides an optical module, including the fiber array assembly in embodiment 1 or 2 or the optical signal receiving structure in embodiment 3.

[0069] In a more refined embodiment, the optical module further includes a housing with an assembly space within it, where the fiber array assembly or the optical signal receiving structure is disposed. In practice, the housing may include a base and a top plate, with the top plate detachably mounted on the base, forming the assembly space between the top plate and the base.

[0070] In a more complete embodiment, the optical module also includes an optical fiber interface, which can be located at one end of the housing. The optical fiber array assembly can be connected to the optical fiber interface via optical fiber 14 so that external optical signals can be transmitted to the optical receiving chip 4 inside the optical module through the optical fiber interface.

[0071] Example 5

[0072] This embodiment provides a coupling method that makes it easier for all channels to achieve high coupling efficiency, including 1. Design stage, including: (1) Determining the focal length of the lens module 2, specifically the focal length F of the lens module 2 can be determined according to parameters such as the material, shape and size of the lens;

[0073] (2) Determine (calculate) the thickness D1 of the base 11 according to the focal length F of the lens module 2; in practice, the thickness D1 can preferably be 0.1mm to 1.2mm, for example, 0.3mm, 0.4mm, 0.5mm, 0.6mm, etc. are preferred.

[0074] (3) Determine the distance L between the lens module 2 and the light-receiving chip 4 based on the focal length F of the lens module 2 and the thickness D1 of the base 11. In practice, the distance L can preferably be 0.1mm to 2mm, for example, 0.3mm, 0.36mm, 0.4mm, 0.5mm, 0.6mm, etc. (4) Determine the thickness D2 of the pad 3 based on the distance L between the lens module 2 and the light-receiving chip 4. In practice, the thickness D2 can preferably be 0.3mm to 2.15mm, for example, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, etc.

[0075] 2. Assembly stage, including: placing the optical fiber 14 and lens module 2 on opposite sides of the base 11, with the lens module 2 corresponding to the end of the optical fiber 14; connecting the pad 3 to the base 11, with the pad 3 and lens module 2 located on the same side of the base 11; placing the light-receiving chip 4 and pad 3 on the same support component 6, with the lens module 2 corresponding to the light-receiving chip 4, as shown in Figure 9, thus completing the coupling between the optical fiber 14 and the light-receiving chip 4. This coupling method can achieve higher coupling efficiency, greatly reducing the probability of collision between the light-receiving chip 4 and the optical fiber 14, effectively improving product yield; and this coupling method is applicable to the above-mentioned fiber array components, optical signal receiving structures, and optical modules, which can increase the range of the coupling position window of the fiber array module 1 while ensuring higher coupling efficiency, making it easier to achieve high coupling efficiency during construction and assembly, thus greatly reducing the process difficulty.

[0076] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A fiber optic array assembly, characterized in that, The system includes a fiber optic array module and a lens module adapted to the fiber optic array module. The fiber optic array module includes a base and at least two optical fibers arranged in an array on one side of the base. The ends of the optical fibers are constructed as bevels. The lens module is located on the other side of the base and corresponds to the end of the optical fiber. The optical signal transmitted by the optical fiber is reflected into the base by the inclined surface. After passing through the base, the optical signal enters the lens module. The lens module is used to converge the optical signal onto the light receiving chip.

2. The fiber optic array assembly according to claim 1, characterized in that, The lens module is attached to the base with adhesive.

3. The fiber optic array assembly according to claim 2, characterized in that, The adhesive used is a refractive index matching adhesive.

4. The fiber optic array assembly according to claim 1, characterized in that, In the lens module, the surface facing the base is the light-inlet surface, and the light-inlet surface is provided with a first anti-reflective film.

5. The fiber optic array assembly according to claim 1, characterized in that, The surface of the lens module facing away from the base is the light-emitting surface, and the light-emitting surface is provided with a second anti-reflective film.

6. The fiber optic array assembly according to claim 1, characterized in that, The thickness of the base is 0.1mm to 1.2mm.

7. The fiber optic array assembly according to claim 1, characterized in that, The lens module uses lenses made of silicon.

8. The fiber optic array assembly according to claim 1, characterized in that, The fiber array module also includes a cover plate, which is connected to the base and at least clamps both sides of the fiber end between the cover plate and the base.

9. The fiber optic array assembly according to claim 8, characterized in that, The cover plate or base has at least two grooves for accommodating optical fibers, with each optical fiber disposed in its respective groove, and the grooves are filled with refractive index matching adhesive.

10. The fiber optic array assembly according to claim 9, characterized in that, The groove is a V-shaped groove; one end of the base is constructed as a slope; one end of the cover plate is constructed as a slope.

11. The fiber optic array assembly according to claim 1, characterized in that, The fiber array module also includes a pad, and the base is connected to the pad. The pad and the lens module are located on the same side of the base. The spacing between the lens module and the light-receiving chip is controlled by the pad.

12. The fiber optic array assembly according to claim 11, characterized in that, The pad is attached to the base with adhesive.

13. A signal receiving structure, characterized in that, The device includes a light-receiving chip, a support component, and an optical fiber array assembly as described in any one of claims 1-10. The light-receiving chip is disposed on the support component, the light-receiving chip corresponds to the lens module, and there is a gap between the lens module and the light-receiving chip.

14. The signal receiving structure according to claim 13, characterized in that, The distance between the lens module and the light-receiving chip is 0.1mm to 2mm.

15. The signal receiving structure according to claim 13, characterized in that, The fiber array assembly also includes a pad, the base is disposed on the pad, the pad is disposed on the support component, and the spacing between the lens module and the light receiving chip is controlled by the pad.

16. The signal receiving structure according to claim 15, characterized in that, The pad is attached to the base with adhesive.

17. The signal receiving structure according to claim 15, characterized in that, The thickness of the pad is 0.3mm to 2.15mm.

18. The signal receiving structure according to claim 15, characterized in that, The light-receiving chip is a photodetector; the supporting component is a PCB board or substrate.

19. An optical module, characterized in that, It includes the fiber optic array assembly according to any one of claims 1-12 or the optical signal receiving structure according to any one of claims 13-18.

20. The optical module according to claim 19, characterized in that, It also includes a housing, which has an assembly space, and the fiber array assembly or the optical signal receiving structure is disposed in the assembly space; It also includes a fiber optic interface, which is located at one end of the housing, and the fiber optic array assembly is connected to the fiber optic interface via optical fiber.

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