A sealed structure of a multi-core optical fiber

Abstract

The application discloses a sealing structure of a multi-core optical fiber, comprising an optical fiber and a sealing assembly, wherein the sealing assembly comprises a first shell and a second shell connected in a head-to-tail mode, a tail end surface of the first shell is provided with N through holes arranged in a close mode, N is a natural number not less than 2, and a head end surface of the second shell is provided with sleeve holes for accommodating the through holes; and the optical fiber sequentially passes through the through holes and the sleeve holes. The multi-hole fiber penetration is adopted, the surface plating layer of the optical fiber is thin and uniform, the optical fiber is prevented from being unevenly distributed in the inner cavity of the sealing sleeve due to fiber twisting, and then the air tightness of the optical fiber is prevented from being affected. Meanwhile, the structure design simplifies the operation difficulty of workers and is convenient for batch processing and production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of optical fiber sealing, in particular to a sealing structure of multi-core optical fiber. BACKGROUND

[0002] Air-tight ribbon optical fiber is widely used due to its high resistance to electrostatic fatigue and hydrogen diffusion-induced optical loss. At present, the mature air-tight optical fiber is mainly small-core products, and the sealing device is mainly designed for air-tight packaging of small-core optical fiber. Typically, the surface coating layer of several optical fibers is peeled off, the surface of the optical fiber is metalized through a chemical plating process, and then the optical fiber is welded with a fiber connector. However, for multi-core ribbon optical fiber products, the performance in batch processing and air-tightness is not ideal. At the same time, the operation requirements for workers are relatively high, which requires a lot of time cost for training, and is not conducive to mass production.

[0003] Therefore, it is necessary to provide a sealing structure of multi-core optical fiber to ensure the air-tightness of multi-core optical fiber. At present, the following problems need to be solved: 1. How to ensure that the multi-core optical fiber is not twisted and bent in the sealing device to ensure the attenuation of the optical fiber. 2. How to prevent the optical fiber from being damaged due to stress concentration under high temperature conditions. 3. How to design the sealing structure to ensure air-tightness while reducing the difficulty of worker operation and realizing batch production. SUMMARY

[0004] In view of the above problems, the technical problem to be solved by the present application is to provide a sealing structure of multi-core optical fiber. The internal structure of the ribbon optical fiber sealing connector is improved, the inner hole is changed to a plurality of parallel long and flat holes, the multi-core optical fiber is uniformly arranged, so that the solder on the surface of each ribbon optical fiber is thin and uniformly distributed, and finally the good air-tightness of the multi-core optical fiber is realized.

[0005] The technical scheme of the present application is as follows:

[0006] A sealing structure of multi-core optical fiber, comprising a ribbon optical fiber and a sealing assembly, the sealing assembly comprising a first shell and a second shell connected end to end, the tail end face of the first shell being provided with N closely arranged through holes, N being a natural number not less than 1, the head end face of the second shell being provided with a sleeve hole for accommodating the through holes; the ribbon optical fiber passes through the through holes and the sleeve hole in turn.

[0007] Further, the shape of the through hole is the same as the shape of the cross section of the ribbon optical fiber, and the size of the through hole is slightly larger than the size of the ribbon optical fiber.

[0008] Further, the head end surface of the first shell is provided with a first groove connected with the through hole, and the tail end surface of the second shell is provided with a second groove connected with the sleeve hole, and the gap between the ribbon optical fiber and the first groove and the second groove is filled with sealant.

[0009] Further, the gap between the ribbon optical fiber and the through hole is sealed by welding.

[0010] Further, the head end surface of the second shell is sleeved outside the tail end surface of the first shell.

[0011] Further, the connection between the head end surface of the second shell and the tail end surface of the first shell is sealed by welding.

[0012] Further, the head end surface of the second shell is sleeved outside the tail end surface of the first shell.

[0013] Further, a detachable support for separating the ribbon optical fiber is arranged at the middle section of the sleeve hole.

[0014] Further, the surface of the ribbon optical fiber cladding between the through hole and the sleeve hole is successively plated with a nickel layer and a gold layer, the thickness of the nickel layer is 3-5 um, and the thickness of the gold layer is 0.1-0.3 um.

[0015] Further, the surface and the inner wall of the sealing assembly are successively plated with a nickel layer and a gold layer from inside to outside, the thickness of the nickel layer is not less than 2.5 um, and the thickness of the gold layer is not less than 0.5 um.

[0016] Compared with the prior art, the beneficial effects of the present application are:

[0017] The through hole is designed to be highly matched with the shape of the ribbon optical fiber, and the number of holes is determined according to the specific core number, which ensures that the plating layer on the surface of the ribbon optical fiber is thin and uniform, avoids uneven distribution of the ribbon optical fiber in the inner cavity of the sealing sleeve caused by twisting of the ribbon optical fiber, and further affects the air tightness of the ribbon optical fiber. At the same time, the structure design simplifies the operation difficulty of workers and is convenient for batch processing and production. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is an appearance schematic view of the sealing structure of the multi-core optical fiber.

[0019] Figure 2 It is a side sectional view of the sealing structure of the multi-core optical fiber.

[0020] Figure 3 It is an appearance schematic view of the sealing assembly.

[0021] Figure 4 It is an appearance schematic view of the first shell.

[0022] Figure 5 is a schematic view of the appearance of the second housing.

[0023] Figure 6 is a side sectional view of the sealing assembly.

[0024] Figure 7 is a front view of the stainless steel bracket. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0026] As shown in Figures 1 to 3 , the present application is a sealing structure of a multi-core optical fiber, comprising a ribbon optical fiber 1 and a sealing assembly, the sealing assembly comprising a first housing 3 and a second housing 2 connected head to tail, a plurality of through holes 31 being arranged closely on the tail end face of the first housing 3, the long sides of the oblong holes being parallel to the long sides of the first assembly end face, and being arranged uniformly in 2 rows and 3 columns, the shape and size of the oblong holes being determined according to the shape and size of the ribbon optical fiber, a sleeve hole 21 being arranged on the head end face of the second housing 2 for accommodating the through holes, and the ribbon optical fiber sequentially passing through the through holes 31 and the sleeve hole 21.

[0027] As shown in Figure 1 and 2 , the surface of the cladding of the ribbon optical fiber between the through holes 31 and the sleeve hole 21 is successively plated with a nickel layer and a gold layer, the thickness of the nickel layer being 3-5 um, and the thickness of the gold layer being 0.1-0.3 um, the housing of the sealing assembly being made of Kovar alloy, the expansion coefficient of which is close to that of solder, thereby ensuring the air tightness of the sealed junction of the ribbon optical fiber. The surface of the housing and the inner cavity wall are successively plated with a nickel layer and a gold layer, the thickness of the nickel layer being ≥2.5 um, and the thickness of the gold layer being ≥0.5 um. The sealing assembly penetrates the metallized ribbon optical fiber, and the gap between the sealing assembly and the ribbon optical fiber is filled with tin-gold solder. In this way, the difference in thermal expansion coefficient between the gold-plated layer on the surface of the ribbon optical fiber and the sealing assembly is greatly reduced, under high temperature conditions, the ribbon optical fiber is no longer deformed or damaged due to uneven stress, at the same time, the gap of the holes is also greatly reduced, thereby ensuring the air tightness of the ribbon optical fiber. The first groove 32 and the second groove 22 of the sealing assembly are filled with cured Araldite, thereby further ensuring the air tightness of the ribbon optical fiber.

[0028] As shown in Figures 3 to 5As shown in the sealing structure of the multi-core optical fiber, the sealing structure comprises six 12-core ribbon optical fibers and a sealing assembly, the sealing assembly comprises a first shell 3 and a second shell 2, the first shell 3 is provided with six flat holes 31 with the same size as the 12-core ribbon optical fiber on the welding end, the long edges of the flat holes 31 are arranged in three rows and two columns in the transverse direction along the long edges of the end face, and each flat hole 31 can accommodate one 12-core single-mode ribbon optical fiber ribbon. This design is beneficial to distinguish different ribbon optical fibers and avoid the multi-core ribbon optical fibers being twisted together, the gaps between the multi-core ribbon optical fibers being uneven, the plating thickness being uneven, and the airtightness of the ribbon optical fiber being affected.

[0029] As shown in Figure 6 and Figure 7 As shown in the sleeve hole, a detachable support 7 for separating the ribbon optical fibers is arranged at the middle section of the sleeve hole. In this way, the ribbon optical fibers can maintain a gap between each other in the sleeve hole, and it is ensured that the ribbon optical fibers will not be curled together due to uneven force. The support 7 can be detached, so that it is no longer necessary to process isolation holes in the sleeve hole, and the process difficulty is greatly reduced.

[0030] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A sealed structure of a multi-core optical fiber including a ribbon optical fiber and a sealing assembly, characterized by: The sealing assembly comprises a first shell and a second shell, the head end surface of the second shell is sleeved outside the tail end surface of the first shell, the tail end surface of the first shell is provided with N through holes arranged in a close manner, N is a natural number not less than 1, the head end surface of the second shell is provided with sleeve holes for accommodating the through holes, and the ribbon optical fibers pass through the through holes and the sleeve holes in sequence. The gap between the ribbon optical fibers and the through holes is sealed by welding. A detachable support for separating the ribbon optical fibers from different through holes is arranged in the middle section of the sleeve hole.

2. The sealed structure of a multicore optical fiber according to claim 1, characterized by: The shape of the through hole is the same as the shape of the cross section of the ribbon optical fiber, and the size of the through hole is slightly larger than the size of the ribbon optical fiber.

3. The sealed structure of a multicore optical fiber according to claim 1, characterized by: The head end surface of the first shell is provided with a first groove connected with the through holes, the tail end surface of the second shell is provided with a second groove connected with the sleeve holes, and the gap between the ribbon optical fibers and the first groove and the second groove is filled with sealant.

4. The sealed structure of a multicore optical fiber according to claim 1, characterized by: The connection between the head end surface of the second shell and the tail end surface of the first shell is sealed by welding.

5. The sealed structure of a multicore optical fiber according to claim 3, characterized by: The depth of the first groove and the second groove is 1 / 3 of the total depth of the first shell and the second shell, respectively.

6. The sealed structure of a multicore optical fiber according to claim 1, characterized by: The surface of the ribbon optical fiber cladding between the through hole and the sleeve hole is plated with a nickel layer and a gold layer in sequence.

7. The sealed structure of a multicore optical fiber according to claim 6, characterized by: The thickness of the nickel layer is 3-5 um, and the thickness of the gold layer is 0.1-0.3 um.

8. The sealed structure of a multicore optical fiber according to claim 1, characterized by: The surface and the inner wall of the sealing assembly are plated with a nickel layer and a gold layer in sequence from inside to outside, the thickness of the nickel layer is not less than 2.5 um, and the thickness of the gold layer is not less than 0.5 um.

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