Double-core contact pin assembly, hybrid optical fiber coupling device and manufacturing method of hybrid optical fiber coupling device

Abstract

The invention relates to the technical field of optical communication, in particular to a dual-core contact pin assembly, a hybrid optical fiber coupling device and a manufacturing method thereof, and the dual-core contact pin assembly comprises a sleeve and a dual-core capillary tube arranged in the sleeve; the double-core capillary tube comprises a first optical fiber and a second optical fiber, the optical fiber diameter and the mode field diameter of the first optical fiber are smaller than those of the second optical fiber, the tail end of the first optical fiber is subjected to beam expanding treatment to form a matched optical fiber, and the mode field diameter of the matched optical fiber is matched with that of the second optical fiber. The mode field diameter of the first optical fiber is expanded to be matched with that of the second optical fiber through beam expansion processing, and the problem of insertion loss caused by mode field mismatch is effectively solved. Compared with a traditional coupling method such as welding transition optical fibers or adding a lens system, the beam expanding processing not only improves the coupling efficiency, but also greatly reduces the size of the device due to the fact that a protective sleeve or a complex lens system does not need to be used, and therefore higher-density device arrangement is achieved, the space utilization rate is improved, and the overall cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of optical communication technology, and in particular to a dual-core ferrule assembly, a hybrid optical fiber coupling device, and a method for manufacturing the same. Background Technology

[0002] In fiber optic communication systems, various new types of optical fibers are constantly emerging, such as large effective area fibers, whose mode field diameters are typically larger than those of ordinary single-mode fibers, generally used for high-speed, long-distance transmission; and polarization-maintaining fibers suitable for special environments, whose structures and mode field characteristics also differ from conventional single-mode fibers. These new fibers and traditional single-mode fibers often need to be fused together in actual network deployments, but due to differences in parameters such as mode field diameter and refractive index distribution, fusion is more difficult and insertion loss is more severe. Furthermore, the reduction in coupling efficiency is particularly prominent when fusion splicing single-mode fibers with different mode field diameters. Efficient coupling between fibers requires that their mode field diameters be matched as closely as possible; otherwise, optical energy cannot be smoothly transmitted from one fiber to another. Taking the common direct fusion splicing method as an example, if the mode field diameters of the two fibers differ significantly, the optical fields cannot overlap well at the splice site, and the optical signal energy cannot be concentrated in the core region for continued transmission. Instead, a considerable portion leaks into the cladding and even the surrounding environment, resulting in a significant decrease in coupling efficiency. This not only reduces the effective transmission power of the optical signal, but also forces the transmitter to increase the optical power to maintain the signal strength, thereby increasing the system's energy consumption and cost. Furthermore, excessively high optical power may also cause nonlinear effects in optical fibers, further interfering with signal transmission.

[0003] Therefore, overcoming the shortcomings of the existing technology is an urgent problem to be solved in this technical field. Summary of the Invention

[0004] The technical problem to be solved by this invention is that different types of optical fiber communication products use single-mode optical fibers with different mode field diameters. Existing hybrid optical fiber coupling methods cannot solve the problems of high insertion loss and low coupling efficiency caused by mode field diameter mismatch when coupling single-mode optical fibers with different mode field diameters. In addition, due to the different mode field diameters, conventional coupling schemes such as fusion splicing of transition fibers increase the device size and cannot achieve device miniaturization.

[0005] The present invention adopts the following technical solution: In a first aspect, the present invention provides a dual-core pin assembly 1, including a sleeve 10 and a dual-core capillary 11 disposed inside the sleeve 10; The dual-core capillary 11 includes a first optical fiber 110 and a second optical fiber 111. The fiber diameter and mode field diameter of the first optical fiber 110 are smaller than those of the second optical fiber 111. The tail end of the first optical fiber 110 is expanded to form a matching optical fiber 112. The mode field diameter of the matching optical fiber 112 matches that of the second optical fiber 111.

[0006] Furthermore, the dual-core capillary 11 includes a first transverse through-hole 113 and a second transverse through-hole 114, wherein the first optical fiber 110 passes through the first transverse through-hole 113 and the second optical fiber 111 passes through the second transverse through-hole 114. The front ends of the first transverse through hole 113 and the second transverse through hole 114 are in the shape of a trumpet.

[0007] Furthermore, the tail end of the dual-core capillary 11 extends beyond the sleeve 10 to couple with other optical devices; Alternatively, the tail end of the dual-core capillary 11 and the front ends of other optical devices are both housed inside the sleeve 10; Alternatively, the tail end of the dual-core capillary 11 and the front end of other optical devices are both housed inside the sleeve 10, and the sleeve 10 is provided with a longitudinal through hole 100, which is used to provide a dispensing channel for dispensing adhesive at the tail end of the dual-core capillary 11 and the front end of other optical devices.

[0008] In a second aspect, the present invention provides a hybrid optical fiber coupling device, comprising the dual-core ferrule assembly 1 and the optical modification unit 2 described in the first aspect; The tail end of the dual-core pin assembly 1 and the front end of the optical modification unit 2 are bonded together.

[0009] Furthermore, the optical modification unit 2 includes: a lens 20 and a filter 21; The dual-core pin assembly 1 is coupled to one side of the lens 20, and the side of the dual-core pin assembly 1 is coupled to the side of the lens 20. The other side of the lens 20 is bonded to the filter 21 to form a dual-core collimator 3.

[0010] Furthermore, a single-core collimator 4 is disposed behind the dual-core collimator 3. The dual-core collimator 3 is coupled to the single-core collimator 4. Both the dual-core collimator 3 and the single-core collimator 4 are encapsulated in the encapsulation tube 5 to form a wavelength division multiplexer.

[0011] Furthermore, the optical modification unit 2 includes: a beam splitter lens 22; The tail end of the dual-core pin assembly 1 is coupled to the front end of the beam splitter 22, and the side of the dual-core pin assembly 1 is bonded to the side of the beam splitter 22 to form a reflector 6. A single-core collimator 4 is disposed behind the reflector 6. The reflector 6 is coupled to the single-core collimator 4. Both the reflector 6 and the single-core collimator 4 are encapsulated in the encapsulation tube 5 to form a beam splitter.

[0012] Thirdly, the present invention provides a method for manufacturing a hybrid optical fiber coupling device, wherein the method for manufacturing the hybrid optical fiber coupling device described in the second aspect comprises: The tail end of the first optical fiber 110 is expanded to change the mode field diameter of the tail end of the first optical fiber 110 so that it matches the mode field diameter of the second optical fiber 111. The first optical fiber 110 and the second optical fiber 111, after being expanded, are fixed in the through hole inside the dual-core capillary tube 11 to form the dual-core capillary tube 11. The dual-core capillary tube 11 is horizontally pushed into the sleeve 10, and the dual-core capillary tube 11 is bonded to the inner wall of the sleeve 10 to form a dual-core pin assembly 1. The tail end of the dual-core pin assembly 1 and the front end of the optical modification unit 2 are bonded together.

[0013] Furthermore, the method also includes: The lens 20 and the filter 21 are bonded together to form the optical modification unit 2; The coupling position between the two is adjusted by the reflection adjustment system, and the two are fixed when the optical indicators meet the requirements to form a dual-core collimator 3; A supplementary optical fiber of the same type as the first optical fiber 110 is fused into the light source fiber to store light through the supplementary optical fiber; The dual-core collimator 3 is placed at the front end of the encapsulation tube 5, and the single-core collimator 4 is placed at the rear end of the encapsulation tube 5. The coupling position between the two is adjusted by an automatic coupling system, and the two are fixed to form a wavelength division multiplexer when the optical indicators meet the requirements.

[0014] Furthermore, the optical modification unit 2 includes a beam-splitting lens 22, and the method further includes: The second optical fiber 111 and the light source fiber are fused together, and the first optical fiber 110 is connected to the optical power meter; The coupling position between the dual-core pin assembly 1 and the beam splitter 22 is adjusted by the reflection adjustment system. When the optical indicators meet the requirements, the two are fixed to form the reflector 6. The coupling position between the reflector 6 and the single-core collimator 4 is adjusted by the transmission adjustment system. When the optical parameters meet the requirements, the two are fixed to form a beam splitter.

[0015] The beneficial effects of this invention are as follows: by expanding the mode field diameter of the first optical fiber to match that of the second optical fiber, the insertion loss problem caused by mode field mismatch is effectively solved. Compared with traditional hybrid fiber coupling methods such as fusion splicing of transition fibers or adding lens systems, this technology not only significantly improves coupling efficiency, but also greatly reduces the device size because it eliminates the need for protective sleeves or complex lens systems. This allows for higher density device arrangement, improves space utilization, and reduces overall cost. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of a dual-core pin assembly provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the end face structure of a dual-core capillary provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a dual-core pin assembly provided in an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the coupling effect between a dual-core pin assembly and other optical elements provided in an embodiment of the present invention; Figure 5 This is a schematic diagram illustrating the coupling effect between a dual-core pin assembly and other optical elements provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of a dual-core collimator provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of an optical modification unit provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of a wavelength division multiplexer provided in an embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of a reflector provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of a beam splitter provided in an embodiment of the present invention; Figure 11 This is a schematic flowchart of a method for manufacturing a hybrid optical fiber coupling device according to an embodiment of the present invention.

[0018] The reference numerals in the accompanying drawings are: Dual-core ferrule assembly 1, sleeve 10, longitudinal through hole 100, dual-core capillary tube 11, first optical fiber 110, second optical fiber 111, matching optical fiber 112, first transverse through hole 113, second transverse through hole 114, wedge groove 115, first adhesive 116, second adhesive 117, optical modification unit 2, lens 20, filter 21, beam splitter lens 22, third adhesive 23, fourth adhesive 24, dual-core collimator 3, single-core collimator 4, collimating lens 40, third optical fiber 41, horn 42, encapsulation tube 5, reflector 6. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as openly inclusive, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples; that is, although they may be incorporated into embodiments or examples using the above terms for reasons such as order and position, it does not limit them to be incorporated in combination by a single embodiment or example.

[0021] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more. Furthermore, for example, the description may use the prefix "A" or "B" to describe the same type of nouns as two independent entities. In this case, the corresponding features defined with "A" and "B" are used only to distinguish between similar entities and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features.

[0022] In describing some embodiments, the terms "coupled," "coupled," and "connected," and their derivative expressions, may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact with each other. Similarly, the term "coupled" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact. However, the terms "connected" or "coupled" may also refer to two or more components that do not have direct contact with each other but still cooperate or interact with each other, such as "optical coupling," "wireless connection," etc. The embodiments disclosed herein are not necessarily limited to the scope of this invention.

[0023] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0024] Example 1: Embodiment 1 of the present invention provides a dual-core pin assembly, such as... Figure 1 As shown, the dual-core ferrule assembly 1 includes a sleeve 10 and a dual-core capillary 11 disposed inside the sleeve 10; the dual-core capillary 11 includes a first optical fiber 110 and a second optical fiber 111, the optical fiber diameter and mode field diameter of the first optical fiber 110 are both smaller than the optical fiber diameter and mode field diameter of the second optical fiber 111, the tail end of the first optical fiber 110 is expanded to form a matching optical fiber 112, the mode field diameter of the matching optical fiber 112 is matched with the mode field diameter of the second optical fiber 111.

[0025] The dual-core ferrule assembly of this embodiment can be applied to various types of optical fiber communication products, including but not limited to wavelength division multiplexers, TAP splitters, and isolators. For ease of use, the input and output ends of these optical fiber communication products are designed with conventional optical fibers, while the internal links are designed with narrow-diameter optical fibers due to space constraints. In this embodiment, the first optical fiber 110 is a narrow-diameter optical fiber with a cladding diameter of 80 μm ± 1 μm; the second optical fiber 111 is a conventional optical fiber with a cladding diameter of 125 μm ± 1 μm and a mode field diameter of 9.6 μm ± 1 μm.

[0026] Not only do narrow-diameter optical fibers and conventional optical fibers differ in cladding diameter, but they also differ in mode field diameter. In optical fiber communication and optical systems, coupling between single-mode fibers with different mode field diameters is a common problem. This is mainly due to the insertion loss and mode mismatch caused by the mode field diameter mismatch. The difference in mode field diameter between different single-mode fibers can lead to discontinuous optical field distribution, causing higher-order mode excitation or energy leakage, and increasing loss.

[0027] In order to enable the first optical fiber 110 to be effectively coupled with the external conventional optical fiber, the tail end of the first optical fiber 110 is expanded to form a matching optical fiber 112. The mode field diameter of the matching optical fiber 112 is the same as that of the second optical fiber 111 (i.e., the conventional optical fiber).

[0028] In practical applications, the sleeve 10 can be a glass sleeve, a plastic sleeve, or a metal sleeve, etc. In order to reduce costs while ensuring reliability, a glass sleeve is selected in this embodiment.

[0029] In one embodiment, see further. Figure 2 The dual-core capillary 11 includes a first transverse through-hole 113 and a second transverse through-hole 114. The first optical fiber 110 passes through the first transverse through-hole 113, and the second optical fiber 111 passes through the second transverse through-hole 114. In order to facilitate the insertion of optical fibers, in a preferred embodiment, the front ends of the first transverse through-hole 113 and the second transverse through-hole 114 are in the shape of a flared mouth.

[0030] like Figure 2 As shown, the optical fibers and through holes correspond one-to-one. The first lateral through hole 113 is used to accommodate the first optical fiber 110, and the second lateral through hole 114 is used to accommodate the second optical fiber 111. In this embodiment of the invention, the diameter of the first lateral through hole 113 is smaller than the diameter of the second lateral through hole 114. Specifically, the diameter of the first lateral through hole 113 can be 82μm±1μm, and the diameter of the second lateral through hole 114 can be 127μm±1μm. The distance between the center of the first lateral through hole 113 and the center of the second lateral through hole 114 can be 131μm±1μm. The diameter of the lateral through holes is larger than the diameter of the optical fiber cladding to ensure that the optical fiber can pass smoothly through the through hole.

[0031] like Figure 3 As shown, in order to fix the optical fiber in the through hole, a wedge-shaped groove 115 is provided on the outer side of the first transverse through hole 113 and the second transverse through hole 114. The two wedge-shaped grooves 115 are symmetrical about the central axis of the dual-core capillary tube 11 and are in the shape of a trumpet. The wedge-shaped groove 115 is used to accommodate the first adhesive 116. In actual use, silicone is provided in the wedge-shaped groove 115. The silicone is used to protect the optical fiber from breakage.

[0032] It should be noted here that, with Figure 1 For example, the tail end of the first optical fiber 110 refers to the right end of the first optical fiber 110, and the lateral direction refers to the direction from the left end to the right end of the first optical fiber 110. In this embodiment, the tail end and lateral direction are based on... Figure 1The orientations shown are described only for the purpose of illustrative purposes and are not intended to require the invention to be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0033] Among them, with Figure 3 Taking a perspective example, a wedge-shaped groove 115 is provided on the upper side of the left port of the first transverse through hole 113, and a wedge-shaped groove 115 is provided on the lower side of the left port of the second transverse through hole 114.

[0034] In practical applications, the first adhesive 116 can be a UV-curable adhesive, epoxy resin adhesive, or cyanoacrylate, etc. Depending on the requirements of the application temperature, curing speed, etc., in a preferred embodiment, the first adhesive 116 is selected as a UV-curable adhesive. In the embodiments of the present invention, the selection of other adhesives is the same as that of the first adhesive 116, and will not be repeated here.

[0035] After the dual-core capillary is fabricated, it is ground, polished, and processed to the required length and angle range. According to actual needs, the beveled end of the dual-core capillary is coated. In this embodiment, the processing angle of the dual-core capillary is 8°, and the coating range is R≤0.2%@1260~1620nm.

[0036] In one embodiment, such as Figure 3 As shown, the tail end of the dual-core capillary 11 extends beyond the sleeve 10 for coupling with other optical devices. The sleeve 10 houses the dual-core capillary 11, and the length of the sleeve 10 is less than the length of the dual-core capillary 11. The inner wall of the sleeve 10 and the dual-core capillary 11 are in contact. When the dual-core capillary 11 is housed within the sleeve 10, the front end of the dual-core capillary 11 is substantially flush with the front sidewall of the sleeve 10, and the tail end of the dual-core capillary 11 protrudes beyond the tail end of the sleeve 10. The sleeve 10 and the dual-core capillary 11 are bonded together with a second adhesive 117 to form a dual-core insert assembly 1.

[0037] In one embodiment, such as Figure 4 As shown, the tail end of the dual-core capillary 11 and the front end of other optical devices are both housed inside the sleeve 10. The length of the dual-core capillary 11 is less than that of the sleeve 10. The sleeve 10 is used to house the tail end of the dual-core capillary 11 and the front end of other optical devices, thus coupling the dual-core capillary 11 and other optical devices together.

[0038] In one embodiment, such as Figure 5As shown, the tail end of the dual-core capillary 11 and the front end of other optical devices are both housed inside the sleeve 10. The sleeve 10 has two longitudinal through holes 100, which are symmetrical along the central axis of the sleeve 10. The longitudinal through holes 100 are used to provide dispensing channels. When the dual-core capillary 11 is coupled with other optical devices, the longitudinal through holes 100 are aligned with the coupling position to dispense adhesive at the tail end of the dual-core capillary 11 and the front end of other optical devices.

[0039] In this embodiment, the mode field diameter of the first fiber 110 is expanded to match that of the second fiber 111 through a beam-expanding process, effectively solving the insertion loss problem caused by mode field mismatch. Compared with traditional hybrid coupling methods such as fusion splicing of transition fibers or adding lens systems, this technology not only significantly improves coupling efficiency but also greatly reduces device size because it eliminates the need for protective sleeves or complex lens systems. This allows for higher density device arrangement, improves space utilization, and reduces overall cost.

[0040] Example 2: Based on the dual-core pin assembly provided in Embodiment 1 above, combined with Figures 6-10 Embodiment 2 of the present invention provides a hybrid optical fiber coupling device, including the dual-core ferrule assembly 1 and the optical modification unit 2; the tail end of the dual-core ferrule assembly 1 and the front end of the optical modification unit 2 are bonded together.

[0041] Different optical modification units 2 can be set according to the type of hybrid fiber coupling device.

[0042] In one embodiment, such as Figure 6 As shown, an optical modification unit 2 is provided on the rear side of the dual-core ferrule assembly 1. The optical modification unit 2 is used for wave splitting, wave combining, or adjusting the propagation direction of the incident beam, etc. The dual-core ferrule assembly 1 and the optical modification unit 2 are bonded together by a fourth adhesive 24 to form the hybrid fiber coupling device. Wherein, in Figure 6 The dual-core pin assembly used is based on Figure 3 The structure shown can be, in other embodiments, used to Figure 4 or Figure 5 The dual-core pin assembly 1 shown is used in this embodiment.

[0043] like Figure 7 As shown, in order to achieve beam collimation and wavelength selection, the optical modification unit 2 includes a lens 20 and a filter 21; the dual-core pin assembly 1 is coupled to one side of the lens 20, and the side of the dual-core pin assembly 1 is coupled to the side of the lens 20; the other side of the lens 20 is bonded to the filter 21 to form a dual-core collimator 3.

[0044] In one embodiment, the optical modification unit 2 includes a lens 20 and a filter 21. The lens 20 collimates the input port beam into a parallel beam, and the filter 21 transmits specific wavelengths and reflects other wavelengths. The tail end of the lens 20 and the front side of the filter 21 are bonded together by a third adhesive 23 to form the optical modification unit 2. Depending on actual needs, the lens 20 can be a spherical lens, an aspherical lens, or a graded refractive index lens, etc., and the filter 21 can be a thin-film interference filter, an arrayed waveguide grating, or a fiber Bragg grating, etc. The lens 20 and the filter 21 can be flexibly combined to suit various application scenarios.

[0045] The tail end of the dual-core capillary 11 in the dual-core pin assembly 1 is coupled to the front end of the lens 20. The side of the dual-core pin assembly 1 and the side of the lens 20 are dotted with adhesive. The adhesive is used to fix the dual-core pin assembly 1 and the optical modification unit 2 together to form a dual-core collimator 3.

[0046] Based on the aforementioned dual-core collimator 3, this embodiment can fabricate a wavelength division multiplexer. Specifically, a single-core collimator 4 is disposed behind the dual-core collimator 3, the dual-core collimator 3 is coupled to the single-core collimator 4, and both the dual-core collimator 3 and the single-core collimator 4 are encapsulated in a packaging tube 5 to form a wavelength division multiplexer.

[0047] like Figure 8 As shown, a single-core collimator 4 is disposed behind the dual-core collimator 3. To ensure the stability of the collimated beam, a preset distance, namely the collimation distance, exists between the single-core collimator 4 and the dual-core collimator 3. A collimating lens 40 is disposed at the front end of the single-core collimator 4. The collimating lens 40 is used to convert the beam passing through the optical modification unit 2 from divergent light into parallel light. To achieve effective coupling, a third optical fiber 41 is disposed inside the single-core collimator 4. The third optical fiber 41 serves as a transmission optical fiber. A flared end 42 is disposed at the rear end of the single-core collimator 4. The flared end 42 is used to accommodate adhesive. Adhesive is applied to the root of the flared end 42 to fix the third optical fiber 41 inside the single-core collimator 4.

[0048] Both the dual-core collimator 3 and the single-core collimator 4 are disposed within the encapsulation tube 5. In actual use, the encapsulation tube 5 can be made of glass, plastic, or metal. To ensure structural stability, in this embodiment of the invention, the encapsulation tube 5 is designed to be made of glass. Both the dual-core collimator 3 and the single-core collimator 4 are encapsulated within the encapsulation tube 5 using adhesive. The encapsulation tube 5, the dual-core collimator 3, and the single-core collimator 4 are bonded together to form a wavelength division multiplexer.

[0049] In one embodiment, such as Figure 9 As shown, the optical modification unit 2 includes: a beam splitter lens 22; the tail end of the dual-core pin assembly 1 is coupled to the front end of the beam splitter lens 22, and the side surface of the dual-core pin assembly 1 is bonded to the side surface of the beam splitter lens 22 to form a reflector 6; wherein, in Figure 9 The dual-core pin assembly used is based on Figure 3 The structure shown can be, in other embodiments, used to Figure 4 or Figure 5 The dual-core pin assembly 1 shown is used in this embodiment.

[0050] like Figure 10 As shown, a single-core collimator 4 is disposed behind the reflector 6. The reflector 6 is coupled to the single-core collimator 4. Both the reflector 6 and the single-core collimator 4 are encapsulated in the encapsulation tube 5 to form a beam splitter.

[0051] The beam splitter 22 can be a TAP beam splitter or other types of beam splitter.

[0052] like Figure 9 As shown, the reflector 6 includes the dual-core pin assembly 1 and the beam-splitting lens 22. The positions of the first transverse through-hole 113 and the second transverse through-hole 114 within the dual-core pin assembly 1 are adjustable, such as... Figure 10 As shown, in this embodiment of the invention, the first optical fiber 110 accommodated in the first transverse through-hole 113 serves as the input port of the reflector 6, the second optical fiber 111 accommodated in the second transverse through-hole 114 serves as the reflection port of the reflector 6, and the third optical fiber 41 in the single-core collimator 4 serves as the transmission port of the beam splitter.

[0053] The beam splitter 22 is used for signal splitting, separating the reflection path from the transmission path. In practical applications, different beam splitting ratios can be achieved by designing the coating of the beam splitter 22 or changing its structure. The reflection path is used to continue transmitting optical signals, ensuring that the main communication link is not affected, and the optical power ratio is generally 95% to 99%. The transmission path is used to monitor optical indicators such as optical power, wavelength, or quality signals in real time, and the optical power ratio is generally 1% to 5%.

[0054] In this embodiment, the dual-core ferrule assembly based on Embodiment 1 can also be applied to optical devices such as isolators, optical switches, and integrated wavelength division multiplexers (IWDM). Optical devices are widely used in many important fiber optic sensing systems such as power grids, 5G communications, amplifiers, radar equipment, and aerospace, and have significant application and economic value. After processing, the coupling parameters of optical fibers with different mode fields can be optimized, and the problem of high insertion loss during fiber splicing of optical fibers with different mode field diameters can be solved.

[0055] Example 3: Based on the aforementioned Embodiments 1 and 2, as Figure 11 As shown, Embodiment 3 of the present invention provides a method for fabricating a hybrid optical fiber coupling device, comprising the following steps: Step 101: Perform a beam expansion process on the tail end of the first optical fiber 110 to change the mode field diameter of the tail end of the first optical fiber 110 so that it matches the mode field diameter of the second optical fiber 111.

[0056] The first optical fiber 110 is generally a narrow-diameter optical fiber, and the second optical fiber 111 is generally a conventional optical fiber. Since the mode field diameters of the first optical fiber 110 and the second optical fiber 111 are not matched, and the mode field diameter of the optical fiber coupled to the first optical fiber 110 is generally the same as that of the second optical fiber 111, the tail end of the first optical fiber 110 needs to be expanded.

[0057] Step 102: Fix the first optical fiber 110 and the second optical fiber 111 after the beam expansion treatment in the through hole inside the dual-core capillary tube 11 to form the dual-core capillary tube 11.

[0058] After the first optical fiber 110 and the second optical fiber 111 pass through the through hole in the dual-core capillary tube 11, adhesive is applied to fix the optical fibers stably in the through hole.

[0059] Step 103: Push the dual-core capillary tube 11 horizontally into the sleeve 10 and bond the dual-core capillary tube 11 to the inner wall of the sleeve 10 to form a dual-core pin assembly 1; bond the tail end of the dual-core pin assembly 1 to the front end of the optical modification unit 2.

[0060] Different optical modification units 2 can be set according to the type of hybrid fiber coupling device.

[0061] In step 101, in order to optimize the insertion loss when single-mode fibers with different mode field diameters are coupled, the mode field diameter at the tail end of the first fiber 110 is expanded to form a matching fiber 112, wherein the mode field diameter of the matching fiber 112 is matched with the mode field diameter of the second fiber 111.

[0062] In step 102, the first optical fiber 110 is horizontally inserted into the first transverse through-hole 113, and the expanded matching optical fiber 112 is placed at the tail end. The second optical fiber 111 is horizontally inserted into the second transverse through-hole 114, with the tail end of the optical fiber flush with the through-hole to form a sealing interface. After determining the positions of the first optical fiber 110 and the second optical fiber 111, the first adhesive 116 is applied to the root of the two wedge grooves 115. The first adhesive 116 is used to bond the first optical fiber 110 and the second optical fiber 111 to the through-hole of the dual-core capillary tube 11 to form the dual-core capillary tube 11.

[0063] In step 103, the tail end of the dual-core capillary tube 11 is aligned with the front end of the sleeve 10, and it is pushed horizontally into the sleeve 10 from front to back. During the pushing process, the dual-core capillary tube 11 adheres to the inner wall of the sleeve 10. After being pushed to the designated position, a second adhesive 117 is applied to the adhesion point to bond the dual-core capillary tube 11 to the inner wall of the sleeve 10 to form a dual-core pin assembly 1.

[0064] In one embodiment, combined Figure 3 The dual-core capillary tube 11 is advanced along the inner wall of the sleeve 10 until the tail end of the dual-core capillary tube 11 protrudes from the rear side wall of the sleeve 10. The optical modification unit 2 is provided on the rear side of the dual-core pin assembly 1. The tail end of the dual-core pin assembly 1 and the front end of the optical modification unit 2 are fixed together by adhesive. The adhesive covers the side of the tail end of the dual-core pin assembly 1 and the side of the front end of the optical modification unit 2.

[0065] In one embodiment, combined Figure 4 The dual-core capillary tube 11 is pushed along the inner wall of the sleeve 10 until it is completely contained within the sleeve 10. The optical modification unit 2 is pushed into the sleeve 10 from the other end, and the front end of the optical unit is contained within the sleeve 10. The optical modification unit 2 is attached to the inner wall of the sleeve 10, and adhesive is applied at the attachment point to fix the front end of the optical modification unit 2 to the tail end of the dual-core pin assembly 1.

[0066] In one embodiment, combined Figure 5 The dual-core capillary tube 11 is advanced along the inner wall of the sleeve 10 until the tail end of the dual-core capillary tube 11 partially overlaps with the longitudinal through hole 100 at the tail end of the sleeve 10. The front end of the optical unit is advanced from the other side of the sleeve 10 until the front end of the optical unit partially overlaps with the longitudinal through hole 100. Adhesive is applied to the longitudinal through hole 100 to fix the tail end of the dual-core pin assembly 1 and the front end of the optical modification unit 2 together.

[0067] In this embodiment, taking the optical modification unit 2, which includes a lens 20 and a filter 21, as an example, the lens 20 and the filter 21 are bonded together to form the optical modification unit 2. The coupling position between the two is adjusted by a reflection adjustment system, and the two are fixed when the optical indicators meet the requirements to form a dual-core collimator 3. A supplementary optical fiber of the same type as the first optical fiber 110 is fused into the light source fiber to store light through the supplementary optical fiber. The dual-core collimator 3 is placed at the front end of the encapsulation tube 5, and the single-core collimator 4 is placed at the tail end of the encapsulation tube 5. The coupling position between the two is adjusted by an automatic coupling system, and the two are fixed when the optical indicators meet the requirements to form a wavelength division multiplexer.

[0068] The lens 20 and the filter 21 are bonded together with a third adhesive 23 to form the optical modification unit 2. The optical modification unit 2 and the dual-core pin assembly 1 are placed in the reflection adjustment system. The reflection adjustment system is used to perform optical adjustments on the optical modification unit 2 and the dual-core pin assembly 1 in five dimensions to ensure accurate alignment of the optical path, adjust the coupling position between the two to minimize the insertion loss, and monitor optical indicators such as return loss to the qualified range. Then, the dual-core pin assembly 1 and the optical modification unit 2 are bonded together with a fourth adhesive 24 to form the dual-core collimator 3.

[0069] After the fourth adhesive 24 has fully cured, the first optical fiber 110, i.e. the input optical fiber, is colored, while the second optical fiber 111, which serves as the reflective optical fiber, is not colored. In actual use scenarios, color marking can help to quickly identify the direction of the optical path, reduce manual inspection time, and quickly locate the transmission port, so as to prioritize collimation or coupling adjustment of the transmission port.

[0070] To prevent insertion loss during the fusion splicing of the second fiber 111 and the first fiber 110, a supplementary fiber is fused into the light source fiber. The supplementary fiber is of the same type as the first fiber 110 and is used for coupling and storing light to optimize the optical signal transmission rate.

[0071] Based on the aforementioned dual-core collimator 3, coupling the dual-core collimator 3 with the single-core collimator 4 further yields a wavelength division multiplexer. The specific fabrication process is as follows: the dual-core collimator 3 and the single-core collimator 4 are placed in an automatic coupling system, and light is passed through the automatic coupling system to adjust the insertion loss and return loss. In this embodiment, during the adjustment process, the first fiber 110 in the dual-core collimator 3 is used as the input port, and the third fiber 41 in the single-core collimator 4 is used as the transmission port. After the optical parameters are adjusted to the qualified range, the encapsulation tube 5 is inserted, and the dual-core collimator 3, the single-core collimator 4, and the encapsulation tube 5 are bonded together using adhesive, so that the dual-core collimator 3 and the single-core collimator 4 are encapsulated in the encapsulation tube 5 to form the wavelength division multiplexer. The wavelength division multiplexer is subjected to optical performance tests, specifically, its insertion loss, isolation, in-band ripple, return loss, and polarization-dependent loss are tested. If all the above indicators meet the standard requirements and the product appearance is found to be correct, the fabrication of the wavelength division multiplexer is complete.

[0072] In this embodiment of the invention, taking the optical modification unit 2 including the beam-splitting lens 22 as an example, based on the aforementioned fabricated dual-core ferrule assembly 1, the dual-core ferrule assembly 1 is coupled with the beam-splitting lens 22 to form a reflector 6. Further coupling the reflector 6 with the single-core collimator 4 yields a beam splitter. The specific fabrication process is as follows: the second optical fiber 111 and the light source fiber are fused together; the first optical fiber 110 is connected to the optical power meter; the coupling position between the dual-core ferrule assembly 1 and the beam-splitting lens 22 is adjusted using a reflection adjustment system; when the optical parameters meet the requirements, the two are fixed to form the reflector 6; the coupling position between the reflector 6 and the single-core collimator 4 is adjusted using a transmission adjustment system; when the optical parameters meet the requirements, the two are fixed to form the beam splitter.

[0073] The dual-core ferrule assembly 1 and the beam splitter lens 22 are placed into the reflection adjustment system to store light. In this embodiment, during adjustment, the second optical fiber 111 is used as the input port and the first optical fiber 110 is used as the reflection port. The input port and the light source fiber are fused together, and the reflection port is connected to the optical power meter. The insertion loss and return loss of the reflection port are adjusted to within the acceptable range through the reflection adjustment system. The dual-core ferrule assembly 1 and the beam splitter lens 22 are bonded together with the fourth adhesive 24 to form the reflector 6.

[0074] The transmission adjustment system stores light. The reflector 6 and the single-core collimator 4 are placed into the transmission adjustment system, and the optical parameters are adjusted to the qualified range through the transmission adjustment system. The system is then fitted into the encapsulation tube 5, and the reflector 6 and the single-core collimator 4 are encapsulated within the encapsulation tube 5 using adhesive to form the beam splitter. The beam splitter is then subjected to optical parameter tests, specifically testing its insertion loss, isolation, in-band ripple, return loss, and polarization-dependent loss. If all the above parameters meet the standard requirements and the product appearance inspection is satisfactory, the fabrication of the beam splitter is complete.

[0075] In practical applications, to ensure versatility and reliability, in the preferred embodiment, the second optical fiber 111, as the input port for interfacing with the user, is made of conventional optical fiber, which is easy to plug in and maintain. To ensure that the monitoring signal can be successfully connected to external testing equipment, in the preferred embodiment, the third optical fiber 41, as the transmission port, is made of conventional optical fiber, which is easy to match with standard interfaces. To optimize loss, in the preferred embodiment, the first optical fiber 110, as the reflection port, is made of thin-diameter optical fiber, which can save space and achieve device miniaturization.

[0076] To ensure the long-term reliability of the device, after the first adhesive 116 is fully cured, the dual-core capillary 11 is subjected to aging tests and temperature cycling. In one embodiment, the dual-core capillary 11 is placed in a room temperature environment to allow the first adhesive 116 to fully cure, releasing stress and preventing fiber misalignment. After the first adhesive 116 is fully cured, the dual-core capillary 11 is placed in a dry environment at 85°C for 48 hours to screen for early failure devices and detect the performance degradation of the first adhesive 116 after long-term use. After the aging test is completed, the dual-core capillary 11 is placed in an environment of -40°C to 85°C for 24 hours to verify the thermomechanical reliability of the device. The curing, aging test, and temperature cycling operations of the second adhesive 117, the third adhesive 23, and the fourth adhesive 24 are the same as those for the first adhesive 116 and will not be described again here.

[0077] In this embodiment, the mode field diameter of the first fiber 110 is expanded to match that of the second fiber 111 through a beam-expanding process, effectively solving the insertion loss problem caused by mode field mismatch. Compared with traditional hybrid coupling methods such as fusion splicing of transition fibers or adding lens systems, this technology not only significantly improves coupling efficiency but also greatly reduces device size because it eliminates the need for protective sleeves or complex lens systems. This allows for higher density device arrangement, improves space utilization, and reduces overall cost.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A dual-core pin assembly, characterized in that, include: Sleeve (10) and a double-core capillary (11) disposed inside the sleeve (10). The dual-core capillary (11) includes a first optical fiber (110) and a second optical fiber (111). The fiber diameter and mode field diameter of the first optical fiber (110) are smaller than those of the second optical fiber (111). The tail end of the first optical fiber (110) is expanded to form a matching optical fiber (112). The mode field diameter of the matching optical fiber (112) matches that of the second optical fiber (111).

2. The dual-core pin assembly according to claim 1, characterized in that, The dual-core capillary (11) includes a first transverse through hole (113) and a second transverse through hole (114). The first optical fiber (110) passes through the first transverse through hole (113), and the second optical fiber (111) passes through the second transverse through hole (114). The front ends of the first transverse through hole (113) and the second transverse through hole (114) are in the shape of a trumpet.

3. The dual-core pin assembly according to claim 1, characterized in that, The tail end of the dual-core capillary (11) extends beyond the sleeve (10) to couple with other optical devices; Alternatively, the tail end of the dual-core capillary (11) and the front ends of other optical devices are both housed inside the sleeve (10); Alternatively, the tail end of the dual-core capillary (11) and the front end of other optical devices are both housed inside the sleeve (10), and the sleeve (10) is provided with a longitudinal through hole (100) for providing a dispensing channel to dispense adhesive at the tail end of the dual-core capillary (11) and the front end of other optical devices.

4. A hybrid fiber optic coupling device, characterized in that, Includes the dual-core insert assembly (1) and optical modification unit (2) as described in any one of claims 1-3; The tail end of the dual-core pin assembly (1) and the front end of the optical modification unit (2) are bonded together.

5. The hybrid fiber optic coupling device according to claim 4, characterized in that, The optical modification unit (2) includes: a lens (20) and a filter (21); The dual-core pin assembly (1) is coupled to one side of the lens (20), and the side of the dual-core pin assembly (1) is coupled to the side of the lens (20). The other side of the lens (20) is bonded to the filter (21) to form a dual-core collimator (3).

6. The hybrid fiber optic coupling device according to claim 5, characterized in that, A single-core collimator (4) is provided behind the dual-core collimator (3). The dual-core collimator (3) is coupled to the single-core collimator (4). Both the dual-core collimator (3) and the single-core collimator (4) are encapsulated in a packaging tube (5) to form a wavelength division multiplexer.

7. The hybrid fiber optic coupling device according to claim 4, characterized in that, The optical modification unit (2) includes: a beam splitter lens (22); The tail end of the dual-core pin assembly (1) is coupled to the front end of the beam splitter (22), and the side of the dual-core pin assembly (1) is bonded to the side of the beam splitter (22) to form a reflector (6). A single-core collimator (4) is provided behind the reflector (6). The reflector (6) is coupled to the single-core collimator (4). Both the reflector (6) and the single-core collimator (4) are encapsulated in a packaging tube (5) to form a beam splitter.

8. A method for fabricating a hybrid optical fiber coupling device, characterized in that, The method for fabricating the hybrid fiber optic coupling device as described in any one of claims 4-7 comprises: The tail end of the first optical fiber (110) is expanded to change the mode field diameter of the tail end of the first optical fiber (110) so that it matches the mode field diameter of the second optical fiber (111). The first optical fiber (110) and the second optical fiber (111) after the beam expansion process are fixed in the through hole inside the dual-core capillary (11) to form the dual-core capillary (11). The dual-core capillary tube (11) is pushed horizontally into the sleeve (10), and the dual-core capillary tube (11) is bonded to the inner wall of the sleeve (10) to form a dual-core pin assembly (1). The tail end of the dual-core pin assembly (1) and the front end of the optical modification unit (2) are bonded together.

9. The method for manufacturing a hybrid fiber optic coupling device according to claim 8, characterized in that, The method further includes: The lens (20) and the filter (21) are bonded together to form the optical modification unit (2); The coupling position between the two is adjusted by the reflection adjustment system, and the two are fixed when the optical indicators meet the requirements to form a dual-core collimator (3). A supplementary optical fiber of the same type as the first optical fiber (110) is fused into the light source fiber to store light through the supplementary optical fiber; The dual-core collimator (3) is placed at the front end of the encapsulation tube (5), and the single-core collimator (4) is placed at the rear end of the encapsulation tube (5). The coupling position between the two is adjusted by an automatic coupling system, and the two are fixed to form a wavelength division multiplexer when the optical indicators meet the requirements.

10. The method for manufacturing a hybrid fiber optic coupling device according to claim 8, characterized in that, The optical modification unit (2) includes a beam splitter lens (22), and the method further includes: The second optical fiber (111) and the light source fiber are fused together, and the first optical fiber (110) is connected to the optical power meter. The coupling position between the dual-core pin assembly (1) and the beam splitter (22) is adjusted by the reflection adjustment system. When the optical parameters meet the requirements, the two are fixed to form a reflector (6). The coupling position between the reflector (6) and the single-core collimator (4) is adjusted by the transmission adjustment system, and when the optical parameters meet the requirements, the two are fixed to form a beam splitter.

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