Universal optical fiber fusion point system and optical fiber fusion point processing method

Abstract

The invention relates to a universal optical fiber fusion point system and an optical fiber fusion point processing method. Firstly, an electro-optical layer 1 with a variable refractive index is formed on the surface of a cladding of an optical fiber welding part, then a thermoelectric light absorption layer 2 is formed on the surface of the electro-optical layer 1, leaked light is absorbed through the thermoelectric light absorption layer 2, the optical power is measured, the refractive index needed by the electro-optical layer 1 is determined by combining the use requirement of a welding point and optical fiber parameters, and then the optical fiber welding part is placed in an electric field 4. The refractive index of the electro-optical layer 1 is regulated to a required value by adjusting the direction and the intensity of the electric field 4, so that the use requirement of the optical fiber fusion point is met. The method has the advantages of being simple in process, wide in application range, outstanding in effect, flexible and efficient in adjusting mode and the like, and has good application and popularization prospects.

Description

Technical Field

[0001] The present invention relates to the field of optical fiber technology, and in particular to a universal optical fiber fusion splice system and an optical fiber fusion splice processing method. Background Art

[0002] Optical fiber (short for optical fiber) is a fiber made of glass or plastic, which usually includes a core, a cladding, and a coating from the inside out. As a tool for light transmission, optical fiber is widely used in communications, medical treatment, industrial processing and other fields. When using optical fiber for light transmission, it is usually necessary to align two optical fibers and connect them together by welding to establish a reliable optical signal transmission channel. When performing the welding operation on the optical fiber, it is necessary to first strip off the coating attached to the surface of the optical fiber, and then use the welding equipment to weld it. For the specific process, please refer to the applicant's earlier patent achievement CN116023045B.

[0003] In order to restore the physical and optical properties of the optical fiber, enhance the flexibility of the optical fiber to protect the bare fiber and the fusion point, the fusion point and the stripped section need to be processed after the fusion is completed. The commonly used fusion point processing method is to use a fiber coating machine to coat a layer of ultraviolet curing coating on the fusion point and the bare fiber surface, and then irradiate ultraviolet light to form an elastic protective layer.

[0004] However, there are large differences in the geometric dimensions, core and cladding refractive indices of different optical fibers. In some practical applications, it is necessary to extract light of a specific power from the fusion point or monitor the optical power extracted near the fusion point. If the optical fiber coating machine is used, it is necessary to frequently replace the clamps and glue for different optical fiber fusion points, which is not only complicated to operate but also cannot meet the needs. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned problems existing in the prior art and to provide a universal optical fiber fusion point system, which includes a fusion-joined optical fiber, an electro-optical layer 1 with a variable refractive index, and a thermoelectric absorption layer 2, wherein the electro-optical layer 1 is coated on the optical fiber fusion joint, and the thermoelectric absorption layer 2 is coated on the outer surface of the electro-optical layer 1.

[0006] Furthermore, the electro-optical layer 1 completely covers the optical fiber fusion-spliced ​​portion, and extends to both ends to cover a portion of the optical fiber that is not fusion-spliced.

[0007] Furthermore, the material of the electro-optical layer 1 is selected from at least one of lithium niobate, iron-doped lithium niobate, and magnesium-doped lithium niobate.

[0008] Furthermore, the thermoelectric light-absorbing layer 2 includes an absorber and a thermoelectric material coating attached to the absorber.

[0009] Furthermore, the absorber is made of metal, such as copper, iron, stainless steel, etc.

[0010] Furthermore, a thermopile sensor for monitoring optical power is built into the side of the thermoelectric light-absorbing layer 2 facing the electro-optical layer 1 .

[0011] Furthermore, the thermopile sensor is specifically a plurality of (ie, more than 2) thermocouples connected in series, and a thermoelectric material coating is coated on the surface thereof.

[0012] Furthermore, the material of the thermoelectric material coating is BB wide spectrum absorption material or EX excimer laser special absorption material.

[0013] Furthermore, the universal optical fiber fusion point system also includes a heat sink 3 , which is coated on the outer surface of the thermoelectric light absorbing layer 2 .

[0014] Furthermore, the universal optical fiber fusion splicing point system also includes an electric field 4 , and the fusion splicing part of the optical fiber is located in the electric field 4 .

[0015] The present invention also provides a universal method for processing optical fiber fusion splices, comprising: forming an electro-optical layer 1 with a variable refractive index on the cladding surface of the optical fiber fusion splice; forming a thermoelectric absorption layer 2 on the outer surface of the electro-optical layer 1; utilizing the thermoelectric absorption layer 2 to absorb leaked light and measure the optical power, and determining the required refractive index of the electro-optical layer 1 in combination with the use requirements of the fusion splice and the optical fiber parameters; placing the optical fiber fusion splice in an electric field 4, and adjusting the direction and intensity of the electric field 4 so that the refractive index of the electro-optical layer 1 increases or decreases to a required value, thereby meeting the use requirements of the optical fiber fusion splice.

[0016] Furthermore, the electro-optical layer 1 and the thermoelectric light-absorbing layer 2 are formed by coating, adsorption, epitaxial growth, adhesion, bonding, and the like.

[0017] The present invention uses electric field to dynamically and flexibly adjust the refractive index of the electro-optical layer, ensuring better forward transmission of the optical fiber at the fusion point, avoiding a large amount of optical fiber leakage from the cladding to the outside, and finally meeting the use requirements of the optical fiber fusion point. By forming multiple functional coating layers on the outer surface of the optical fiber cladding, it can not only provide physical protection for the optical fiber fusion point, but also adapt to optical fiber fusion points with different parameters, and can dynamically change the refractive index of the electro-optical layer outside the optical fiber cladding as needed, so that it meets the actual use requirements of the fusion point, and has strong versatility and practical value. The method also has the advantages of simple process, wide applicability, outstanding effect, etc., and has a good prospect for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The figure is a flow chart of a general method for processing optical fiber fusion splicing points.

[0019] Figure 2 It is a structural schematic diagram of a universal optical fiber fusion splicing point system.

[0020] Wherein: 1-electro-optic layer, 2-thermoelectric absorption layer, 3-heat sink, 4-electric field, 5-left optical fiber, 51-left fiber core, 52-left cladding, 6-right optical fiber, 61-right fiber core, 62-right cladding. DETAILED DESCRIPTION

[0021] In order to enable ordinary technicians in the field to fully understand the technical solutions and beneficial effects of the present invention, further description is given below in conjunction with specific embodiments and drawings.

[0022] like Figure 1-2 As shown, the left optical fiber 5 and the right optical fiber 6 are aligned and then fused. The fused optical fiber cannot ensure that the fusion point meets various usage requirements. For this reason, we have developed a universal optical fiber fusion point system and a corresponding optical fiber fusion point processing method. The whole process includes three steps, as follows:

[0023] S101: depositing an electro-optical layer 1 on the surface of the optical fiber cladding where the optical fiber coating layer is stripped by coating, adsorption or epitaxial growth, and using the electro-optical layer 1 to wrap the optical fiber fusion point and the vicinity of the fusion point.

[0024] The fusion point to be processed is formed by stripping and welding the left optical fiber 5 and the right optical fiber 6 of any geometric size or refractive index parameter. The left optical fiber 5 and the right optical fiber 6 are both common single-clad optical fibers, and the diameters of the left core 51 and the right core 61 are both 10μm, and the refractive index is about 1.45. At the same time, the diameters of the left cladding 52 and the right cladding 62 are both 125μm, and the refractive index is about 1.46. The stripping length of the left optical fiber 5 and the right optical fiber 6 is 10mm, and the bare fiber length after welding is 20mm.

[0025] The material of the electro-optic layer 1 is an electro-optic material with variable electro-refractive index, such as lithium niobate, iron-doped lithium niobate, magnesium-doped lithium niobate, etc. Taking iron-doped lithium niobate as an example, its initial refractive index is 1.48, and a thin film is formed on the surface of the bare fiber cladding after fusion by adsorption, which completely wraps the left optical fiber 5 and the right optical fiber 6 after stripping and fusion and the surrounding area.

[0026] S102: A thermoelectric light-absorbing layer 2 is formed on the surface of the electro-optical layer 1 by adhesion, adsorption or bonding. The specific process is as follows: first, a light absorber is prepared, and then a thermopile sensor is installed on the light absorber. Next, a layer of thermoelectric material is coated on the surface of the thermopile sensor. After drying, a thermoelectric light-absorbing layer 2 is formed. Finally, the side of the thermoelectric light-absorbing layer 2 coated with the thermoelectric material is coated on the surface of the electro-optical layer 1.

[0027] In this process, it is necessary to ensure that the thermoelectric absorption layer 2 completely wraps the electro-optical layer 1 and the optical fiber segment it covers. The function of the thermoelectric absorption layer 2 is to absorb the light leaking from the optical fiber fusion point or the optical fiber cladding to the electro-optical layer 1, and at the same time, the thermopile sensor built into the thermoelectric absorption layer 2 performs real-time power measurement of the absorbed light. The thermopile sensor is a thermopile structure formed by multiple thermocouples connected in series. Its surface is coated with thermoelectric materials such as BB wide-spectrum absorption material and EX excimer laser special absorption material, and is fixed on the surface of the electro-optical layer 1 by adhesion. The working principle of the thermopile sensor is: the thermoelectric absorption layer 2 converts the absorbed light into heat, the heat is transferred to the thermopile and forms a temperature gradient field, and the thermopile sensor converts the temperature change into an electrical signal output, thereby obtaining the magnitude of the optical power.

[0028] S103: Under the initial refractive index conditions of the electro-optical material in the electro-optical layer 1, according to the optical power measured in the previous step and the actual requirements for the use of the fusion splicing point, combined with the aforementioned optical fiber geometric dimensions, optical fiber stripping section length, optical fiber core and optical fiber cladding refractive index and other parameters, determine the refractive index change trend or parameter range required for the electro-optical material with variable refractive index.

[0029] Specifically, the initial refractive index of the variable electro-optic material is 1.48, which is higher than the refractive index of the left optical fiber 5 and the right optical fiber 6 and the optical fiber cladding (52 and 62) of 1.46, and the light does not meet the total reflection condition when it is transmitted in the optical fiber cladding. Considering that the total length of the optical fiber stripping is 20mm, a large amount of light in the optical fiber cladding will leak into the electro-optic layer 1 and be absorbed by the thermoelectric absorption layer 2. In order to avoid this problem and improve the safety and stability of the fusion point, it is necessary to reduce the light leaking into the electro-optic layer 1 as much as possible, so it is necessary to change (here it needs to be reduced) the refractive index of the variable electro-optic material until the optical power measured by the thermoelectric absorption layer 2 is as low as a certain level.

[0030] S104: Place the fused left optical fiber 5 and right optical fiber 6 in an electric field, adjust the intensity and direction of the electric field according to the refractive index change trend or parameter range of the electro-optical material with variable refractive index determined in the previous step, and dynamically adjust the refractive index of the electro-optical material with variable refractive index in real time until it meets the use requirements.

[0031] Specifically, in order to ensure the actual use of the fusion point, the refractive index of the electro-optic material with variable electro-optical refractive index needs to be reduced. To achieve this goal, we place the processed optical fiber fusion point and the stripped section in the electric field 4, and use an electric field of sufficient intensity to reduce the refractive index of the electro-optic material with variable electro-optical refractive index. During this period, the optical power measured by the thermoelectric absorption layer 2 is observed in real time. When the optical power is reduced to the allowable range, the electric field 4 is kept unchanged. At this time, the optical fiber fusion point can meet the use requirements.

[0032] In order to ensure the temperature stability and safety of the optical fiber fusion point, in some cases, it may be necessary to set a circle of heat sink 3 on the outer surface of the thermoelectric light absorbing layer 2, and use the heat sink 3 to completely wrap the thermoelectric light absorbing layer 2 and the electro-optical layer 1 underneath, the optical fiber fusion point, etc. The heat sink 3 is cooled by water or air to effectively dissipate heat from the thermoelectric light absorbing layer 2 and the left and right optical fibers, etc., to protect the normal use of the optical fiber.

[0033] In summary, the present invention utilizes an electric field to dynamically adjust the refractive index of the electro-optical material with variable refractive index wrapped outside the cladding near the optical fiber fusion point. On the one hand, it realizes the physical protection of the optical fiber fusion point. On the other hand, it can adapt to the optical fiber fusion point with different parameters to meet various different usage requirements. It has strong versatility and practical value.

Claims

1. A universal optical fiber splicing point system, characterized in that: The system comprises a fused optical fiber, an electro-optic layer (1) with a variable refractive index, and a thermoelectric light absorbing layer (2), wherein the electro-optic layer (1) is coated on the optical fiber fusion portion, and the thermoelectric light absorbing layer (2) is coated on the outer surface of the electro-optic layer (1).

2. The universal optical fiber splicing point system according to claim 1, characterized in that: The electro-optical layer (1) completely covers the optical fiber fusion-spliced ​​portion and extends to both ends to cover the unfused optical fiber portions.

3. The universal optical fiber splicing point system according to claim 1, characterized in that: The material of the electro-optical layer (1) is selected from at least one of lithium niobate, iron-doped lithium niobate, and magnesium-doped lithium niobate.

4. The universal optical fiber splicing point system according to claim 1, characterized in that: The thermoelectric light-absorbing layer (2) comprises an absorber and a thermoelectric material coating attached to the absorber, wherein the material of the absorber is selected from at least one of copper, iron, and stainless steel, and the material of the thermoelectric material coating is selected from at least one of BB wide-spectrum absorption material and EX excimer laser special absorption material.

5. The universal optical fiber splicing point system according to claim 1, characterized in that: A thermopile sensor for monitoring optical power is built into the side of the thermoelectric light-absorbing layer (2) facing the electro-optical layer (1).

6. The universal optical fiber splicing point system according to claim 5, characterized in that: The thermopile sensor is specifically two or more thermocouples connected in series, and a thermoelectric material coating is coated on the surface of the thermocouple.

7. The universal optical fiber splicing point system according to claim 1, characterized in that: The universal optical fiber fusion point system also includes a heat sink (3), wherein the heat sink (3) is coated on the outer surface of the thermoelectric light absorption layer (2).

8. The universal optical fiber splicing point system according to claim 1, characterized in that: The universal optical fiber fusion point system also includes an electric field (4), and the fusion point of the optical fiber is located in the electric field (4).

9. A universal method for processing optical fiber fusion splices, characterized in that The processing method comprises: forming an electro-optical layer (1) with a variable refractive index on the cladding surface of the optical fiber fusion splice; forming a thermoelectric absorption layer (2) on the outer surface of the electro-optical layer (1); utilizing the thermoelectric absorption layer (2) to absorb leaked light and measure the optical power, and determining the required refractive index of the electro-optical layer (1) in combination with the use requirements of the fusion splice point and the optical fiber parameters; placing the optical fiber fusion splice site in an electric field (4), and adjusting the direction and intensity of the electric field (4) so ​​that the refractive index of the electro-optical layer (1) increases or decreases to a required value.

10. The method according to claim 9, characterized in that: The electro-optical layer (1) and the thermoelectric light-absorbing layer (2) are formed by coating, adsorption, epitaxial growth, adhesion and bonding.

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