Method and device for selectively removing metal coating layer of gold-plated optical fiber

Abstract

The invention provides a method and device for selectively removing a metal coating layer of a gold-plated optical fiber, and the device comprises at least one transparent short tube, a chemical reagent solution with a certain concentration, and at least one gold-plated optical fiber of which the metal coating layer needs to be locally removed at a sensing point. The local removal area of the metal coating layer of the gold-plated optical fiber is arranged in a short tube filled with a chemical reagent solution, and the metal coating layer is removed through reaction under required reaction conditions. According to the method, the metal coating layer attached to the local solution of the short tube is removed through reaction, and selective reaction removal of the metal coating layer is achieved, that is, the metal layer in a non-sensing measuring point area is completely reserved.

Description

Technical Field

[0001] The invention relates to a method and a device for selectively removing a metal coating layer of a gold-plated optical fiber, and belongs to the technical fields of advanced functional materials and optical fiber sensing. Background Art

[0002] The emergence of fiber optic sensing technology has provided a development direction for the leapfrog improvement of sensing monitoring capabilities in strong electromagnetic environments, distributed and structural integration, etc., especially in the field of aerospace, it has special advantages in the efficient acquisition of temperature and strain response data of aircraft ground test structures, and online structural health monitoring applications during the service life of aircraft. It will greatly enrich the traditional aircraft structure sensing monitoring technology system and improve the capability level. It is one of the advanced sensing technologies with urgent application needs.

[0003] In view of the differences in the operating temperature range, the optical fiber materials used in optical fiber sensing technology include quartz optical fiber sensing materials, sapphire optical fiber sensing materials, ceramic optical fiber sensing materials, etc. In the use environment close to 1000℃ (600-1000℃), gold-plated quartz optical fiber is the most mature optical fiber material currently used.

[0004] Theoretically, quartz fiber sensors can be used for a long time at nearly 1000℃. However, due to the complexity of the use environment and objects, especially for the use environment of mechanical and thermal coupling, the quartz fiber is integrated with the structure, and the quartz fiber sensing material is very easy to break due to interference such as structural deformation / vibration, which in turn causes the sensor to fail. For this reason, on the one hand, the sensor is armored with protective layers such as corundum and stainless steel to improve the structural strength / performance stability of the sensor. On the other hand, a surface metal coating solution is proposed to improve the high-temperature mechanical properties of the quartz fiber body, that is, the ability to resist external interference damage.

[0005] Among them, gold-plated quartz fiber sensing materials have two applications. One is distributed sensing. When using it, the end of the gold-plated quartz fiber needs to be processed to remove a certain length (about 3cm) of metal coating, so that the quartz fiber and the fiber connector can be packaged to connect the demodulation equipment. The other way is fiber grating sensing. In addition to removing the metal coating at the end of the fiber, when quartz fiber is used in fiber grating sensing, it is necessary to pass the laser beam through the fiber cladding and then act on the fiber core layer to prepare the fiber grating structure. However, when gold-plated quartz fiber is used to prepare the sensor, the presence of the metal layer will cause the laser to be unable to transmit for fiber grating processing. Therefore, it is necessary to selectively remove a certain length of metal coating at the fiber grating measurement point position (the fiber grating length is about 5mm, so the removal length is between 5mm-1cm).

[0006] The removal of the metal coating of gold-plated quartz optical fiber has high requirements for position accuracy and removal length accuracy. First, the position of the grating measuring point in the fiber grating sensor is determined by the fiber grating sensor layout plan (usually U-shaped or serpentine). In actual use, the center position of the metal coating to be removed (along the length direction) should coincide with the center position of the fiber grating measuring point in the design, so there is a requirement for the control accuracy of the removal position (about 0.5mm). Secondly, for femtosecond laser direct writing fiber grating sensors, the length of the fiber grating itself at each sensing point is about 5mm±1mm. When removing the metal coating at this position, it is very important to control the accuracy of the metal coating removal length under the premise that the position accuracy meets the requirements. In order to prevent failure caused by excessive removal length and incomplete sensor structure caused by too small removal length, the metal coating removal length accuracy is required to be ±1mm.

[0007] Currently, the selective removal of the metal coating of gold-plated quartz optical fiber can generally be achieved by chemical or physical methods. The physical method is mainly achieved by mechanical stripping. Generally, a blade is used to scrape the metal coating of the gold-plated quartz optical fiber at a certain angle. After applying a certain force to cut off the coating, a delamination is introduced between the metal coating and the quartz optical fiber, and then the force is continuously applied along the delamination direction to remove the metal coating along the length direction. In this process, the length of the metal coating removal is generally based on human visual observation and manual control, and for a single fiber grating measurement point, it is necessary to scrape 2-3 times around the circumference to completely remove the metal coating. In addition, for the blade mechanical stripping solution, due to the differences between different operators in manual operation and the fluctuation of manual force, it is easy to introduce defects in the quartz optical fiber material body at the lower end of the knife due to excessive force and angle during the stripping of the metal coating. The existence of this defect will cause the subsequent preparation of the sensor to have a decreased anti-bending performance (easy to break).

[0008] The chemical method is to use chemical reagents to react and remove the metal coating of the gold-plated quartz optical fiber. There are generally two ideas. One is to drop the chemical reagent at the position where the metal coating needs to be removed. The accuracy of the dripping solvent position is difficult to control. At the same time, the solution will spontaneously diffuse to both ends along the length of the gold-plated optical fiber, and the diffusion length is difficult to control. In addition, an open reaction environment is used, and the chemical reagent will become ineffective due to the rapid volatilization of water in the air. The second is the immersion method, which can be whole or partial immersion. Whole immersion requires the preparation of a solution pool of chemical reagents. After isolating and protecting the non-removal area, the gold-plated optical fiber is immersed in the solution pool as a whole. A large amount of solution is required, and additional protection is required for the non-removal area, which increases the cost of protection and chemical reagents. Partial immersion uses a beaker, quartz glass box, etc. to hold the chemical solvent, and the gold-plated optical fiber is placed in the chemical solvent section by section. The amount of chemical solvent used is small. This method is not suitable for high-density arrays of removal positions, such as quasi-distributed sensing. 8-10 fiber grating sensor measurement points need to be prepared on a single gold-plated quartz optical fiber, and the spacing is relatively close. It is constrained by the turning radius of the gold-plated optical fiber itself (about 3cm, and the optical fiber is prone to physical damage if the radius is too small). It is difficult to achieve the simultaneous invasion of two metal coatings at close distances into the solution, and the sequential reaction removal scheme is extremely time-consuming.

[0009] Therefore, physical removal of the metal coating is prone to introduce material defects / damage, which affects the mechanical properties of the fiber Bragg grating sensor prepared based on the material and limits its large-scale engineering application. Conventional chemical removal of the metal coating has the disadvantages of being difficult to ensure position accuracy and removal length accuracy, and the solution is complex, costly, and inconvenient to operate. Summary of the invention

[0010] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method and device for selectively removing the metal coating of a gold-plated optical fiber, which is efficient, low-damage, achieves selective removal, is simple to operate, and takes into account position accuracy, removal length accuracy, and high-density array removal.

[0011] The technical solution of the present invention is a method for selectively removing the metal coating layer of a gold-plated optical fiber, comprising the following steps:

[0012] Determine the type and concentration of chemical solvents and the material, inner diameter, length and quantity of short tubes;

[0013] Prepare chemical reagent solutions and fabricate short tubes; and

[0014] Reaction removal of the metal coating of gold-plated optical fiber,

[0015] The gold-plated optical fiber metal coating removal area is placed in a short tube filled with a chemical reagent solution, reacted under the desired reaction conditions, and repeated until the metal coating of the removal area is completely removed.

[0016] A device for selectively removing the metal coating of a gold-plated optical fiber comprises at least one transparent short tube, a chemical reagent solution of a certain concentration, and at least one gold-plated optical fiber to which the metal coating needs to be partially removed. The local removal area of ​​the metal coating of the gold-plated optical fiber is placed in the short tube filled with the chemical reagent solution, and reacts under the required reaction conditions to remove the metal coating.

[0017] The beneficial effects of the present invention compared with the prior art are as follows:

[0018] (1) The present invention realizes the selective reaction removal of the metal coating layer based on the local solution-attached metal coating layer of the short tube, that is, the metal layer in the non-sensing point area is completely retained;

[0019] (2) The present invention realizes reaction removal with low solution volume requirements. Compared with the solution of preparing a solution pool, isolating and protecting the non-removal area and then immersing the gold-plated quartz optical fiber sample in the solution pool as a whole, this solution uses a short tube for localized reaction, does not require additional protection of the non-removal area, and reduces the solution volume of the entire process;

[0020] (3) The present invention has formulated the optimal inner diameter and reaction time of the short tube, solidified the overall operation process, and removed the metal coating layer of the gold-plated quartz optical fiber measuring point with low damage and high precision (position, length), thereby improving the sensor yield (mechanical properties) and supporting the application and promotion of gold-plated quartz optical fiber sensing materials;

[0021] (4) The metal coating removal method of the present invention is designed by matching the inner diameter of the short tube with the concentration of the chemical solution, taking into account both the removal accuracy and the removal efficiency;

[0022] (5) The present invention is simple and quick to operate, shortens the operation time, and maximizes the reaction effect of the chemical solution;

[0023] (6) The overall operation process of the present invention has the potential for mechanical semi-automation and batch production. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a flow chart of the present invention;

[0025] Figure 2 This is a schematic diagram of the device of Example 1 of the present invention. DETAILED DESCRIPTION

[0026] The present invention is described in detail below with reference to specific examples and accompanying drawings.

[0027] like Figure 1 As shown, the present invention provides a method for selectively removing the metal coating layer of a gold-plated optical fiber, comprising the following steps:

[0028] Determine the type and concentration of the chemical solvent and the material, inner diameter, length and quantity of the short tubes.

[0029] Furthermore, in this step, the short tube is made of a transparent material that does not react with the chemical solvent. Preferably, the inner diameter of the short tube is 4 to 5 mm. Further preferably, the larger the inner diameter of the short tube is, the better, while ensuring that the chemical solvent is filled in the short tube without overflowing.

[0030] In the present invention, by controlling the diameter of the short tube, the chemical reagent solution injected into the short tube is prevented from overflowing or leaking under the constraint of surface tension, thereby achieving local immersion and selective removal of the metal coating layer. Under the premise of using less chemical reagents, high precision of the removal position and length of the metal coating layer is guaranteed.

[0031] The number and length of the short tubes in this step are determined according to the number of locations and the removal length of the metal coating layer required to be removed from the gold-plated optical fiber.

[0032] In this step, the type of chemical solvent is determined according to the type of metal coating layer of the gold-plated optical fiber. The higher the concentration of the chemical solvent, the more beneficial it is to the removal of the coating layer. However, after exceeding a certain concentration, the increase in removal efficiency corresponding to the increase in unit concentration will decrease. The preferred concentration mass percentage is not less than 10%. The specific selection can be made by referring to the known technology in the art.

[0033] Further preferably, this step provides a method for determining the concentration of a preferred chemical solvent and the inner diameter of the short tube, as follows:

[0034] A series of chemical solvent concentrations are selected according to a certain step length, and the maximum inner diameter corresponding to the short tube being filled with chemical solvent without overflowing under each chemical solvent concentration is determined, which is the optimal short tube inner diameter under this concentration.

[0035] It is further preferred that the concentration of the chemical solvent is optimized with the number of repeated removals as an optimization target to ensure that the metal coating layer in the removal area is removed cleanly, with the minimum number of times being best, and then taking into account its storage conditions and reaction costs, etc., comprehensive consideration is taken to determine the optimal concentration.

[0036] Furthermore, the short tube is generally made of a transparent plastic tube. If the chemical solvent is corrosive, inorganic materials such as glass / quartz are preferred.

[0037] Prepare chemical reagent solutions and make short tubes.

[0038] In this step, a chemical reagent solution is prepared according to the determined type and concentration of the chemical reagent, and the required short tubes are manufactured according to the determined short tube material, inner diameter, quantity, and length.

[0039] Reactive removal of the metal coating of gold-plated optical fiber.

[0040] The gold-plated optical fiber metal coating removal area is placed in a short tube filled with a chemical reagent solution, and reacts under the desired reaction conditions to remove the metal coating.

[0041] Furthermore, the reaction conditions required for removal in this step are related to the type of metal coating layer and the type of chemical reagent used, and can refer to the reaction conditions known in the art.

[0042] Furthermore, the reaction time is determined according to the inner diameter of the short tube and the concentration of the chemical reagent solution.

[0043] Further, this step provides the following two preferred methods, and those skilled in the art can select any of the following methods as needed:

[0044] 1. Insert the gold-plated optical fiber into the short tube, fix the short tube in the area where the metal coating of the gold-plated optical fiber is removed, and fill the short tube with chemical reagent solution.

[0045] 2. Fill the short tube with chemical reagent solution, insert the gold-plated optical fiber into the short tube filled with chemical reagent solution, and fix the short tube in the area where the metal coating of the gold-plated optical fiber is to be removed.

[0046] Furthermore, before the short tube is installed on the gold-plated optical fiber, the removal area is marked on the metal coating layer of the gold-plated optical fiber to facilitate the determination of the fixing position of the short tube.

[0047] After cleaning, repeat the reaction removal step of the gold-plated optical fiber metal coating.

[0048] Further, the number of repetitions of this step is determined according to the concentration and the inner diameter of the short tube. Preferably, the number of repetitions is within three times, and the minimum number is the best, to ensure that the metal coating layer in the removal area is completely removed.

[0049] In this step, after each reaction, the chemical reagent residue in the short tube is cleaned to ensure that the short tube is dry and clean when the chemical reagent is injected next time.

[0050] Since the metal coating layer of the gold-plated optical fiber is generally 10-20 microns, which is thicker than the gold-plated layer of conventional electronic devices (hundreds of nanometers), the time required for reaction removal and the solution concentration / dosage need to be optimized to compress the time of the overall process flow. The present invention matches the inner diameter of the short tube with the concentration of the chemical solution, that is, under given solution concentration conditions, the optimal inner diameter of the short tube corresponding to the solution not overflowing and leaking under surface tension constraints (the smaller the inner diameter, the better) and the minimum number of repeated steps (the inner diameter is about 200,000, the better, and the amount of solution in a single reaction is large).

[0051] Furthermore, the present invention also provides a device for selectively removing the metal coating of a gold-plated optical fiber, comprising at least one transparent short tube, a chemical reagent solution of a certain concentration, and at least one gold-plated optical fiber that needs to have its metal coating partially removed. The area where the metal coating of the gold-plated optical fiber needs to be partially removed is placed in the short tube filled with the chemical reagent solution, and reacts under the desired reaction conditions to remove the metal coating.

[0052] Furthermore, the number and length of the transparent short tubes correspond one to one with the number and length of the regions where the metal coating layer of the gold-plated optical fiber needs to be partially removed.

[0053] Furthermore, the inner diameter of the transparent short tube is determined based on the standard that the short tube is filled with chemical solvent without overflowing. Preferably, the inner diameter of the transparent short tube is 4 to 5 mm.

[0054] More preferably, the concentration of the chemical solvent is not less than 10% by mass.

[0055] Furthermore, there exists an optimal inner diameter of the short tube for the chemical reagent solution and the inner diameter of the short tube, which corresponds to the minimum number of cycle steps required under the constraint of surface tension and the solution does not overflow or leak under given solution concentration conditions.

[0056] Furthermore, the device also includes a gold-plated optical fiber operating table, and the gold-plated optical fiber whose metal coating needs to be partially removed is fixedly installed on the gold-plated optical fiber operating table, and the gold-plated optical fiber operating table can fix multiple gold-plated optical fibers.

[0057] Furthermore, a scale is set on the surface of the gold-plated optical fiber operating table, and the center position of the short tube is aligned with the center position of the area where the metal coating needs to be removed through the scale on the surface of the operating table to ensure position accuracy.

[0058] Furthermore, the gold-plated optical fiber and the transparent short tube are fixed to the operating table by means of waterproof tape or a magnetic pressure plate (which is a metal operating table).

[0059] Example

[0060] The metal coating layer of the optical fiber is a gold layer, and the chemical solvent used is a solution of iodine and potassium iodide (KI-I) with a concentration of about 11%. The inner diameter of the transparent plastic short tube is 5mm.

[0061] Use Figure 2 The device shown is implemented by the following steps:

[0062] Chemical solvent solution preparation.

[0063] The chemical solvent is a solution of iodine and potassium iodide (KI-I), with a ratio of 100 ml of water, 10 g of potassium iodide, and 2.5 g of elemental iodine. When preparing, potassium iodide must be fully dissolved in water first, and then the iodine must be dissolved in the potassium iodide solution.

[0064] The prepared solution should be placed in a dark container and kept away from light (light will cause iodine to evaporate and affect the effect).

[0065] (This solution is mainly used for gold layer removal. For other copper-plated, aluminum-plated, nickel-plated quartz optical fibers, corresponding reaction solutions need to be prepared, but the remaining contents are common (when the solution is a corrosive liquid, inorganic transparent tubes such as glass / quartz can be used)).

[0066] Gold-plated optical fiber metal coating removal area marking.

[0067] For the quartz optical fiber connector end where the metal coating needs to be removed, and the fiber grating measurement point position, use an oil-based marker pen to mark the edge of the area where the metal coating needs to be removed.

[0068] Metal coating layer is removed by reaction.

[0069] For the quartz optical fiber connector end where the metal coating needs to be removed, and the fiber Bragg grating measurement point, use a transparent plastic tube with an inner diameter of 5 mm to cut a plastic short tube of the same length and quantity as the area where the metal coating needs to be removed.

[0070] Place the gold-coated optical fiber on the operating table and fix it at one end (with waterproof tape).

[0071] After passing the plastic short tube through the gold-plated quartz optical fiber, place it at the fiber Bragg grating measuring point where the metal coating needs to be removed and the length of the short tube matches. The plastic short tube is aligned with the center of the area where the metal coating needs to be removed through the scale on the surface of the operating table to ensure the position accuracy. Use waterproof tape or a magnetic pressure plate (a metal operating table is required) to fix the position of the plastic short tube, and then fix the other end of the gold-plated quartz optical fiber (waterproof tape).

[0072] Use a disposable plastic capillary to absorb the iodine and potassium iodide solutions, and inject them from one end of the plastic short tube until the short tube is completely filled with the solution through the tube wall (due to the existence of surface tension, the injection process is quick and not easy to overflow. For excess dripping reagents, use a dust-free cloth to absorb and wipe the table surface before re-injecting. During the process, be careful to avoid bubbles in the capillary and short tube. If there are bubbles, use a dust-free cloth to remove them and re-inject.

[0073] Cover the operating table with a blackout cloth for 1-1.5 hours to allow the solution in the short tube to fully react with the metal coating. (When the indoor temperature is high, it is recommended to seal the operating table to prevent water from evaporating too quickly and affecting the reaction effect)

[0074] Remove the shade cloth, use water (it is recommended to use a disposable capillary to absorb clean water and then squeeze it out, or immerse the entire operating table in a pool of water) to gently buffer the solution, and then use a dust-free cloth to absorb the remaining water, especially the residual water in the plastic short tube.

[0075] According to the thickness of the metal coating layer of the gold-plated quartz optical fiber, repeat the above steps of solution injection, light shielding reaction, and clean water cleaning until the metal coating layer is completely removed (for a gold layer with a thickness of about 15 microns and an inner diameter of the plastic short tube of 5 mm, it can be completely removed after three cycles of the steps).

[0076] Example 2

[0077] In this operation, the order of fixing the position of the plastic short tube and injecting the solution is reversed from that in Example 1. At this time, the solvent is injected into the plastic short tube without optical fiber (more efficient), and then the short tube is inserted from one end of the gold-plated quartz optical fiber that is not fixed on the operating table, and moved to the corresponding metal coating removal position, i.e., the fiber grating measurement point, and then the position of the plastic short tube is fixed by waterproof tape or a magnetic pressure plate (needs to be a metal operating table), and then the end of the gold-plated optical fiber is fixed (waterproof tape). When using this sequence, it is necessary to use a dust-free cloth to remove the solvent remaining on the surface of the non-removal area due to the movement of the solvent-containing plastic short tube.

[0078] For the same fiber grating measurement point layout of gold-plated quartz optical fiber material, when repeated preparation, the solvent is cleaned and the tapes at both ends are removed. The gold-plated quartz optical fiber can be replaced to quickly prepare the next sample, and a single operating table can fix multiple gold-plated quartz optical fibers at the same time.

[0079] Morphology inspection of quartz optical fiber after metal coating removal.

[0080] The quartz optical fiber material with the metal coating removed is placed under an optical microscope to observe whether there are impurities adhering to the area where the metal coating is removed and whether there is any damage introduced to the edge.

[0081] The quartz optical fiber material with the metal coating removed is inspected with a ruler to confirm that the position and length of the metal coating removal meet the design requirements. If the error is greater than 2mm, it is considered as scrap.

[0082] After the inspection is correct, the sample can be used to prepare the gold-plated fiber grating sensor.

[0083] Parts of the present invention that are not described in detail are well known to those skilled in the art.

Claims

1. A method for selectively removing the metal coating of a gold-plated optical fiber, characterized in that: The following steps are involved: Determine the type and concentration of chemical solvents and the material, inner diameter, length and quantity of short tubes; Prepare chemical reagent solutions and make short tubes; and Reaction removal of the metal coating of gold-plated optical fiber, The gold-plated optical fiber metal coating removal area is placed in a short tube filled with a chemical reagent solution, reacted under the desired reaction conditions, and repeated until the metal coating of the removal area is completely removed.

2. The method for selectively removing the metal coating of a gold-plated optical fiber according to claim 1, characterized in that: The chemical reagent solution in the short tube is filled with the chemical reagent solution without overflowing under the constraint of surface tension.

3. The method for selectively removing the metal coating of a gold-plated optical fiber according to claim 2, characterized in that: The gold-plated optical fiber is inserted into a short tube, which is fixed in the area where the metal coating of the gold-plated optical fiber is removed, and the short tube is filled with a chemical reagent solution; or the short tube is filled with a chemical reagent solution, and the gold-plated optical fiber is inserted into the short tube filled with the chemical reagent solution, which is fixed in the area where the metal coating of the gold-plated optical fiber is removed.

4. The method for selectively removing the metal coating of a gold-plated optical fiber according to claim 3, characterized in that: The concentration of the chemical solvent solution is optimized with the number of repeated removals as an objective to ensure that the metal coating layer in the removal area is completely removed, with the minimum number of repetitions being the best, while taking into account the storage conditions and reaction costs, and comprehensively considering to determine the optimal concentration.

5. The method for selectively removing the metal coating of a gold-plated optical fiber according to claim 4, characterized in that: The concentration of the chemical solvent and the inner diameter of the short tube are determined by selecting a series of chemical solvent concentrations according to a certain step length, and determining the maximum inner diameter corresponding to the short tube being filled with chemical solvent without overflowing at each chemical solvent concentration, which is the optimal inner diameter of the short tube at this concentration.

6. The method for selectively removing the metal coating of a gold-plated optical fiber according to claim 4, characterized in that: The inner diameter of the short tube is designed to match the concentration of the chemical reagent solution, that is, under given solution concentration conditions, the optimal inner diameter of the short tube corresponds to the minimum number of repeated steps without the solution overflowing or leaking under surface tension constraints.

7. A method for selectively removing the metal coating layer of a gold-plated optical fiber according to any one of claims 1 to 6, characterized in that: The inner diameter of the short tube is 4-5 mm; the mass percentage of the chemical solvent solution concentration is not less than 10%.

8. A method for selectively removing the metal coating of a gold-plated optical fiber according to any one of claims 1 to 6, characterized in that: The number and length of the short tubes are determined according to the number of locations where the metal coating needs to be removed from the gold-plated optical fiber and the length of the removal area; the chemical reagent solution is prepared according to the determined type and concentration of the chemical reagent, and the required short tubes are made according to the determined short tube material, inner diameter, number, and length; the required reaction conditions are related to the type of metal coating and the type of chemical reagent used, and the reaction time is determined according to the inner diameter of the short tube and the concentration of the chemical reagent solution; before the short tube is installed on the gold-plated optical fiber, the removal area is marked on the metal coating of the gold-plated optical fiber to facilitate the determination of the fixed position of the short tube; after each reaction, the chemical reagent residue in the short tube is cleaned to ensure that the short tube is dry and clean when the chemical reagent is injected next time.

9. A method for selectively removing the metal coating of a gold-plated optical fiber according to any one of claims 1 to 6, characterized in that: The short tube is made of a transparent material that does not react with chemical solvents.

10. A device for selectively removing the metal coating of a gold-plated optical fiber, characterized in that: The method comprises at least one transparent short tube, a chemical reagent solution of a certain concentration, and at least one gold-plated optical fiber whose metal coating needs to be partially removed. The area where the metal coating of the gold-plated optical fiber needs to be partially removed is placed in the short tube filled with the chemical reagent solution, and reacts under the required reaction conditions to remove the metal coating.

11. The device for selectively removing the metal coating of a gold-plated optical fiber according to claim 10, characterized in that: The inner diameter of the transparent short tube is determined based on the standard that the short tube is filled with chemical solvent without overflowing.

12. The device for selectively removing the metal coating of a gold-plated optical fiber according to claim 11, characterized in that: The number and length of the transparent short tubes correspond one to one with the number and length of the regions where the metal coating layer of the gold-plated optical fiber needs to be partially removed.

13. The device for selectively removing the metal coating of a gold-plated optical fiber according to claim 11, characterized in that: The chemical reagent solution and the inner diameter of the short tube exist, under given solution concentration conditions, and under the constraint of surface tension, the solution does not overflow or leak, and the optimal inner diameter of the short tube corresponds to the minimum number of circulation steps required.

14. The device for selectively removing the metal coating of a gold-plated optical fiber according to claim 11, characterized in that: The inner diameter of the transparent short tube is 4-5 mm; the mass percentage of the chemical solvent concentration is not less than 10%.

15. A device for selectively removing the metal coating of a gold-plated optical fiber according to any one of claims 10 to 14, characterized in that: It also includes a gold-plated optical fiber operating table. The gold-plated optical fiber that needs to partially remove the metal coating layer is fixedly installed on the gold-plated optical fiber operating table. The gold-plated optical fiber operating table can fix multiple gold-plated optical fibers.

16. The device for selectively removing the metal coating of a gold-plated optical fiber according to claim 15, characterized in that: The gold-plated optical fiber operating table is provided with a table surface scale, and the center position of the short tube is aligned with the center position of the area where the metal coating layer needs to be removed through the table surface scale.

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