Optical fiber device for online stripping of cladding light and preparation method thereof
By introducing a lossy core rod into the cladding of the fiber device and absorbing cladding light, the problem of residual light in existing fiber lasers affecting the beam quality is solved, improving the reliability of the fiber device and reducing costs.
Patent Information
- Application Number
- CN202510071580.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-16
- Publication Date
- 2025-04-04
AI Technical Summary
In existing fiber lasers, pump light is not completely absorbed by doped fibers, resulting in residual light output through the cladding, affecting the beam quality. The traditional stripping method reduces the fiber reliability and increases costs.
Introducing a lossy mandrel with a lossy medium into the cladding of the fiber device, absorbing and consuming cladding light, improving the reliability of the fiber device and reducing manufacturing/use costs.
By introducing a lossy mandrel, the cladding light is effectively stripped, the reliability of optical fiber devices is improved, and the cost of use is reduced, avoiding damage to the cladding structure in traditional methods.
Smart Images
Figure CN119758516A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present invention relate to the technical field of optical fiber devices, and in particular to an optical fiber device for online stripping of cladding light and a preparation method thereof. Background Art
[0002] Fiber lasers have gradually become an emerging choice in industrial processing, medical cosmetology, military scientific research and other fields due to their advantages such as good beam quality, high transmission efficiency and low maintenance cost. In order to achieve high-quality laser output, fiber lasers usually use doped fibers as active fibers, and form lasers by injecting pump light into the active fiber. However, the pump light in the fiber is often impossible to be completely absorbed by the doped fiber, and the residual light will be directly output through the fiber cladding and the output end of the laser, which will seriously affect the quality of the output beam spot. Therefore, stripping the residual light in the fiber cladding is crucial to improving the quality of the output beam. The traditional way to filter out the cladding light is to directional destroy the cladding structure of the transmission fiber. The most common method is wet etching or laser etching. The strength of the fiber under this process will be reduced, and the reliability will also be reduced; at the same time, the cumbersome manufacturing process will also lead to an increase in cost. Summary of the invention
[0003] The present invention provides an optical fiber device for online stripping of cladding light and a preparation method thereof. By introducing a lossy core rod with a lossy medium into the cladding of the device to absorb and consume the cladding light, the problems of low reliability and high manufacturing / use cost of related stripping devices in the prior art can be solved.
[0004] As a first aspect of the present application, the present application discloses an optical fiber device for online stripping of cladding light, which comprises:
[0005] An optical fiber body, the optical fiber body comprising a fiber core and a cladding disposed on the fiber core, wherein the fiber core and the cladding are coaxially disposed; and
[0006] At least one lossy core rod is disposed inside the cladding, the extension direction of the lossy core rod is the same as the axial direction of the optical fiber body, and there is a preset distance between the lossy core rod and the optical fiber core.
[0007] As a preferred solution, the extension direction of the lossy core rod is the same as the axial direction of the fiber core.
[0008] As a preferred solution, the lossy core rod is arranged to be rotated and extended around the fiber core.
[0009] As a preferred solution, the distance between the center of the lossy core rod and the center of the fiber core is greater than the distance between the center of the lossy core rod and the outside of the cladding.
[0010] As a preferred embodiment, the cross-sectional shape of the lossy core rod is any one of circular, D-shaped and polygonal.
[0011] As a preferred solution, the lossy core rod is doped with metal elements, and the metal elements include at least one of cobalt, iron, chromium, manganese and nickel.
[0012] As a preferred solution, it also includes a coating layer, and the coating layer covers the cladding layer.
[0013] As another aspect of the present application, a method for preparing an optical fiber device is also provided. The optical fiber device includes at least one lossy core rod. The preparation method includes:
[0014] S1. Providing an optical fiber preform and at least one lossy core rod;
[0015] S2, forming at least one core rod channel inside the optical fiber preform, wherein each core rod channel is eccentrically arranged relative to the central axis of the optical fiber preform to accommodate a lossy core rod respectively;
[0016] S3, performing a melting and shrinking process on the optical fiber preform and the lossy core rod received in the core rod channel to form a new cladding preform;
[0017] S4. Drawing the new cladding preform rod to obtain an optical fiber device.
[0018] As a preferred solution, the cladding new preform rod is subjected to a drawing process to obtain an optical fiber device, including:
[0019] By adopting the direct wire drawing process, the extension direction of the loss core rod is the same as the axial direction of the new cladding preform rod.
[0020] As a preferred solution, the cladding new preform rod is subjected to a drawing process to obtain an optical fiber device, including:
[0021] The rotary wire drawing process is adopted to obtain a lossy core rod which is rotated and stretched around the central axis of a new cladding preform rod.
[0022] In summary, the optical fiber device for online stripping of cladding light provided by the present application includes an optical fiber body and at least one lossy core rod, the optical fiber body includes a core and a cladding coated on the core, the core and the cladding are coaxially arranged; the lossy core rod is arranged inside the cladding, and its extension direction is the same as the axial direction of the optical fiber body, and there is a preset distance between the core and the optical fiber. The optical fiber device of the present application introduces a lossy core rod with a lossy medium into the cladding to absorb and consume the cladding light, which is beneficial to improve the reliability of the device; at the same time, the optical fiber device can be directly connected to the optical path under low power conditions, and the use cost is low. The present application solves the problem that the reliability of the current cladding light stripping technology is reduced due to the need to directional damage the cladding of the transmission optical fiber. The stripping of the cladding light in the optical fiber no longer needs to be achieved by destroying the cladding structure, and an optical fiber-based, online optical fiber device is realized. The reliability of the device is greatly improved, and its use cost is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is a structural schematic diagram of an optical fiber device provided by the present application;
[0024] Figure 2 yes Figure 1 A schematic cross-sectional view of an optical fiber device is provided;
[0025] Figure 3 is a schematic structural diagram of another optical fiber device provided by the present application;
[0026] Figure 4 yes Figure 3 A cross-sectional schematic diagram of another optical fiber device is provided;
[0027] Figure 5 yes Figure 1 A cross-sectional schematic diagram of another optical fiber device is provided;
[0028] Figure 6 It is a structural schematic diagram of an optical fiber device provided by the present application;
[0029] Figure 7 yes Figure 6 A refractive index profile of a fiber optic device is provided;
[0030] Figure 8 yes Figure 6 A fiber optic device is provided that shows the loss characteristics of the optical fiber under different rotation drawing processes;
[0031] Fig. 9 yes Figure 6 A simulated light intensity distribution of a fiber optic device is provided;
[0032] Fig.10 yes Figure 6 Optical phase information of an optical fiber device provided;
[0033] Fig.11 yes Figure 1 A cross-sectional schematic diagram of another optical fiber device is provided;
[0034] Fig.12 It is a schematic diagram of a method for preparing an optical fiber device provided in the present application. DETAILED DESCRIPTION
[0035] The present invention will be further described in detail below in conjunction with the accompanying drawings and examples. It will be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings. It is obvious to those skilled in the art that various modifications and changes can be made in the present invention without departing from the spirit or scope of the present invention. Therefore, the present invention is intended to cover modifications and changes of the present invention that fall within the scope of the corresponding claims (technical solutions for protection) and their equivalents. It should be noted that the implementation methods provided in the embodiments of the present invention can be combined with each other without contradiction.
[0036] Figure 1 is a schematic diagram of the structure of an optical fiber device provided in this application, Figure 2 yes Figure 1 A cross-sectional schematic diagram of an optical fiber device is provided, Figure 3 is a schematic diagram of the structure of another optical fiber device provided by the present application, Figure 4 yes Figure 3 Another cross-sectional schematic diagram of an optical fiber device is provided, see Figure 1-Figure 4 The optical fiber device 100 provided in the embodiment of the present application includes an optical fiber body, which includes a core 10 and a cladding 20 covering the core 10, wherein the core 10 and the cladding 20 are coaxially arranged. The optical fiber device 100 also includes at least one lossy core rod 30, which is located inside the cladding 20, and has an extension direction that is the same as the axial direction of the optical fiber body, and is spaced from the core 10 by a preset distance, and is used to absorb cladding light in the cladding 20.
[0037] The extension direction refers to the tendency or path of the lossy core rod (object or system) to extend or expand in a specific direction; the cladding light refers to the light leaking from the core 10 to the cladding 20.
[0038] Figure 1-Figure 2 Only one lossy core rod 30 is shown in the cladding 20. Figure 3-Figure 4 It is shown that two lossy core rods 30 are arranged in the cladding 20, and more embodiments are not shown one by one.
[0039] Specifically, refer to Figure 1-Figure 4When the optical fiber device 100 provided in the present application is in use, light is refracted from the outside into the core 10. The refractive index of the core 10 is greater than the refractive index of the cladding 20, which can cause the light to be deflected toward the optical fiber axis and propagate forward along the core 10. In this way, light leakage can be prevented. However, in the process of light propagation, it is inevitable that some leaked light will enter the cladding 20 to form cladding light, resulting in heat concentration in the cladding 20, causing hazards such as thermal effects. The present application adopts the symmetrical structural design of traditional transmission optical fibers, that is, the cladding 20 and the core 10 are coaxial and concentric structures. At least one doped lossy core rod 30 is introduced at an appropriate position inside the cladding 20. The lossy core rod 30 has a high loss characteristic and can absorb the cladding light in the cladding 20. In this way, problems such as optical fiber damage caused by heat concentration in the cladding 20 can be improved.
[0040] It should be noted that, when setting the position of the lossy core rod 30, the present application needs to ensure that the interval between the lossy core rod 30 and the fiber core 10 has a preset distance, that is, no contact, so that the light normally transmitted in the optical fiber 10 can be prevented from leaking into the cladding 20. Among them, the preset distance can be reasonably designed according to parameters such as the actual core diameter, the cladding diameter, the lossy core rod 30 diameter, and the energy of the cladding light. Specifically:
[0041] Optional, reference Figure 2 When setting the position of the lossy core rod 30, it is also necessary to consider that the distance L1 between the center of the lossy core rod 30 and the center of the fiber core 10 is greater than the distance L2 between the center of the lossy core rod 30 and the outside of the cladding 20, that is, L1>L2. In the embodiment of the present application, it is found in the test that when the parameters such as the diameter of the fiber core 10, the diameter of the lossy core rod 30, and the thickness of the cladding 20 are fixed, combined with the absorption efficiency of the lossy core rod 30 for the cladding light, the position of the lossy core rod 30 usually has an optimal value range, so the present application can be reasonably set according to actual needs.
[0042] For example, the diameter of the lossy core rod 30 is 50um, the distance L1 from the center of the lossy core rod 30 to the center of the fiber core 10 is 75um, and the distance L2 from the center of the lossy core rod 30 to the outside of the cladding 20 is 50um. In the optical fiber device obtained by this parameter setting, the lossy core rod 30 has a high absorption rate for the cladding light.
[0043] Furthermore, the shape of the lossy core rod 30 can also be designed. Figure 5 yes Figure 1 A cross-sectional schematic diagram of another optical fiber device is provided. Figure 1-Figure 5 The cross-sectional shape of the loss core rod 30 is any one of a circle, a D-shaped shape, and a polygon, such as a triangle, a hexagon, an octagon, etc., in order to increase the absorption rate of the loss core rod 30 to the cladding light.
[0044] Furthermore, the extension direction of the lossy core rod 30 can have various forms. For a feasible implementation, refer to Figure 1 The extension direction of the lossy core rod 30 is the same as the extension direction of the fiber core 10.
[0045] The extension direction refers to the expansion or extension of the sacrificial core rod (object or system) in one direction. It should be noted that in this application, extension refers to one direction, which is longitudinal; extension can be in all directions, which is transverse.
[0046] Specifically, when the optical fiber device 100 is drawn, at least one lossy core rod 30 may be added to the cladding 20, and the interval between the lossy core rod 30 and the core 10 is a preset distance. Exemplarily, a direct drawing process is adopted to linearly draw the core 10, the cladding 20, and the lossy core rod 30 into the optical fiber device 100, and the lossy core rod 30 absorbs the cladding light in the cladding 20.
[0047] Figure 6 This is a schematic diagram of the structure of an optical fiber device provided by this application, refer to Figure 6 In a feasible implementation, the lossy core rod 30 is rotated and stretched around the fiber core 10. It can also be understood that the lossy core rod 30 is rotated and stretched around the fiber core 10. Exemplarily, when the optical fiber device 100 is drawn, the lossy core rod 30 can be rotated and set in the cladding 20, and the interval between the lossy core rod 30 and the fiber core 10 is a preset distance. The fiber core 10, the cladding 20, and the lossy core rod 30 are rotated and drawn into the optical fiber device 100 by a rotary drawing process. Such a setting is conducive to increasing the probability of the cladding light passing through the lossy core rod 30, thereby improving the efficiency of the lossy core rod 30 in absorbing the cladding light.
[0048] For example, refer to Figure 6 The loss core rod 30 is made of asymmetric submicron porous glass. The cladding 20 is doped with asymmetric submicron porous glass. Figure 7 yes Figure 6 The refractive index profile of a fiber optic device is provided. Figure 8 yes Figure 6 The invention provides a fiber optic device and the loss characteristics of the fiber optic under different rotation drawing processes. Fig. 9 yes Figure 6 The simulated light intensity distribution of a fiber optic device is provided. Fig.10 yes Figure 6 Provides optical phase information of an optical fiber device. Figure 7-10 It reflects the display of the same optical fiber under different scanning states. Figure 7 , Fig. 9 and Fig.10 The three figures show the cross-sections of the lossy core rod in different states when it is made of porous glass. Figure 8As shown in FIG. 1 , the preliminary simulation shows that the loss of the cladding light by the 10 mm long lossy core rod 30 is 14 dB, so it can be known that the rotational drawing increases the loss of the cladding light. Furthermore, by increasing the drawing rotation rate or the optical fiber length, such as when a 20 mm long lossy core rod 30 is used, the loss of the cladding light by the lossy core rod 30 can be further increased, which can also be understood as improving the absorption effect of the lossy core rod 30 on the cladding light.
[0049] Fig.11 yes Figure 1 Another cross-sectional schematic diagram of an optical fiber device is provided, based on the above embodiment, with reference to Fig.11 The optical fiber device 100 further includes a coating layer 40 . The coating layer 40 covers the cladding layer 20 . The coating layer 40 is used to protect the optical fiber device 100 .
[0050] It should be noted that Figure 1-Figure 11 The optical fiber device 100 further includes a coating layer, which covers the cladding 20 , which is not shown in the present application.
[0051] Based on the above embodiments, Figure 1-Figure 11 The lossy core rod 30 is doped with metal elements, and the metal elements include at least one of cobalt, iron, chromium, manganese, and nickel. Specifically, the lossy core rod 30 is doped with some metal elements, such as cobalt ions, iron ions, chromium ions, manganese ions, nickel ions, etc. The ratio between the various metal elements can be reasonably designed according to the attenuation band area, and the embodiment of the present application is not limited.
[0052] Based on the above embodiments, Figure 1-Figure 11 The material of the fiber core 10 provided in the embodiment of the application includes silicon dioxide doped with germanium and phosphorus, and the material of the cladding 20 includes silicon dioxide. The manufacturing cost of the optical fiber device 100 can be comparable to that of ordinary optical fibers, which is conducive to mass production.
[0053] Based on the same inventive concept, the embodiment of the present application also provides a method for preparing an optical fiber device, wherein the optical fiber device includes at least one lossy core rod, Fig.12 Schematic diagram of a method for preparing an optical fiber device provided in the present application, the preparation method comprising:
[0054] S1. Providing an optical fiber preform and at least one lossy core rod;
[0055] S2, forming at least one core rod channel inside the optical fiber preform, wherein each core rod channel is eccentrically arranged relative to the central axis of the optical fiber preform to accommodate a lossy core rod respectively;
[0056] S3, performing a melting and shrinking process on the optical fiber preform and the lossy core rod received in the core rod channel to form a new cladding preform;
[0057] S4. Drawing the new cladding preform rod to obtain an optical fiber device.
[0058] In step S1, the optical fiber preform includes an optical fiber body, the optical fiber body includes a fiber core and a cladding disposed on the fiber core, and the fiber core and the cladding are coaxially disposed.
[0059] In one embodiment, the steps of preparing the optical fiber preform are as follows:
[0060] Step S111, making the core rod: the fluorine-doped quartz liner is cleaned, corroded and dried, and then the PCVD (Plasma-enhanced Chemical Vapor Deposition, PCVD, plasma vapor deposition technology) process is used to continuously inject oxides such as silicon tetrachloride and / or germanium tetrachloride, and the plasma vapor deposition technology is used to continuously form silicon dioxide and germanium dioxide deposits on the surface of the liner by heating, thereby forming the core 10 and cladding 20 of the optical fiber.
[0061] Step S112, cleaning the core rod: After the completed core rod is melted and shrunk, it is cleaned and dried. The melting and shrinking refers to removing the air inside to form a solid rod.
[0062] Step S113, making a preform: matching and assembling the core rod and the sleeve, and forming a conventional optical fiber preform after melting and shrinking. Exemplarily, the sleeve is a pure quartz rod.
[0063] In one embodiment, the steps of preparing the consumable core rod in step S1 are as follows:
[0064] Step S121, making a core rod: After cleaning, etching and drying the pure quartz liner, PCVD process is used to continuously inject oxides such as silicon tetrachloride and / or germanium tetrachloride, especially doping phosphorus, cobalt and aluminum elements, and transporting them into the quartz liner through the chloride gas corresponding to the elements. The doping amount of aluminum element is 1mol% to 3mol%, the doping amount of phosphorus element is 0.1mol% to 0.3mol%, and the doping amount of cobalt element is generally 0.02mol% to 0.2mol%.
[0065] Step S122, cleaning the core rod: cleaning, corroding and drying the core rod after the drilling.
[0066] In the process of preparing the lossy core rod, in order to improve the efficiency of coupling the cladding light to the lossy core rod, the lossy core rod can be punched to destroy the interface condition. As an example, cold machine air can be used to uniformly punch holes on the core rod surface, with a hole diameter of 1um to 5um, a hole depth of 10um to 20um, and a hole spacing of 20um to 50um.
[0067] For step S2, the core rod channel can be formed by punching holes in the cladding of the optical fiber preform along its axial direction, and the channel size is processed corresponding to the loss core rod size. For example, the punching size is 0.5 mm larger than the loss core rod size, and cleaning, etching and drying are performed after the punching is completed.
[0068] In step S3, the lossy core rod and the punched optical fiber preform are reassembled, and a new cladding preform is obtained after melting and shrinking. The new cladding preform is then subjected to a drawing process to obtain the optical fiber device required by the present application.
[0069] Exemplarily, the drawing process in step S4 is: placing the obtained cladding new preform on a fiber drawing tower to draw the fiber, during which the preform can be rotated at a constant speed of 100 to 200 rpm, and after drawing, an optical fiber that can be used to strip the optical fiber cladding light can be obtained. Then, a coating operation is performed on it to obtain a complete cladding light attenuation optical fiber.
[0070] Based on the above embodiment, in step S4, the preparation method may include:
[0071] By adopting the direct wire drawing process, the extension direction of the loss core rod is the same as the axial direction of the new cladding preform rod.
[0072] refer to Figure 1 When the optical fiber device 100 is drawn, at least one lossy core rod 30 can be added to the cladding 20, and a direct drawing process is adopted to draw the core 10, the cladding 20, and the lossy core rod 30 in a uniform straight line to form the optical fiber device 100. The extension direction of the obtained lossy core rod 30 is the same as the extension direction of the core 10, and the interval between the lossy core rod 30 and the core 10 is a preset distance. The lossy core rod 30 can absorb the cladding light in the cladding 20.
[0073] Based on the above embodiment, in step S4, the preparation method may include:
[0074] The rotary wire drawing process is adopted to obtain a lossy core rod which is rotated and stretched around the central axis of a new cladding preform rod.
[0075] Exemplary, reference Figure 6 When the optical fiber device 100 is drawn, a rotary drawing process is adopted to uniformly rotate and draw the core 10, the cladding 20, and the loss core rod 30 to form the optical fiber device 100. The obtained loss core rod 30 is rotated and extended around the core 10. The interval between the loss core rod 30 and the core 10 is a preset distance. The loss core rod 30 can absorb the cladding light in the cladding 20.
[0076] It can be understood that the above preparation method can be particularly used to prepare the optical fiber device for online stripping of cladding light with synchronous removal in the present application.
[0077] Based on the same inventive concept, the embodiment of the present application also provides a method for using an optical fiber device, wherein the optical fiber device provided by the above embodiment is used to transmit signal light, and the power of the signal light includes a first power and a second power, and the first power is less than the second power. The signal light can be a low-power laser used for optical communication, or a high-power laser used in laser processing and other fields. Figure 1-Figure 6 and Fig.11 The optical fiber device 100 further includes a coating layer, and the coating layer covers the cladding layer 20. The method for using the optical fiber device 100 includes:
[0078] When the transmission signal light is at the first power, the optical fiber is connected to a position where the cladding light needs to be filtered out.
[0079] Specifically, refer to Figure 1-Figure 6 and Fig.11 When the optical fiber device 100 is used to transmit a signal light of a first power, for example 0 to 50 W, the optical fiber device 100 can be directly integrated into a position where the cladding light needs to be filtered out, and the lossy core rod 30 can directly absorb and consume the cladding light in the cladding 20 to avoid thermal effects.
[0080] When the transmission signal light is the second power, the coating layer of a part of the optical fiber is stripped, and the optical fiber is connected to the position where the cladding 20 light needs to be filtered out, and heat dissipation treatment is added to the position where the coating layer is stripped.
[0081] The stripping length of the coating layer is controlled according to the loss coefficient of the loss core rod 30 .
[0082] Specifically, when the second power signal light is transmitted by 100, for example, 50 to 10000W, the coating layer 40 of a part of the optical fiber device 100 is stripped according to the loss coefficient of the loss core rod 30, and a heat dissipation treatment is provided for the stripped coating layer 40. The heat dissipation treatment can be performed by attaching a metal plate, water cooling, and the like.
[0083] When transmitting low-power and high-power signal light, the optical fiber device proposed in the embodiment of the present application has a simpler manufacturing process than the prior art, and there is no need to corrode and then coat the cladding of the optical fiber device. The lossy core rod can directly absorb the cladding light. The optical fiber device has the advantages of good mechanical reliability and low manufacturing cost. It is a cladding light stripping solution with high reliability and low cost.
[0084] It should be noted that the stripping efficiency per unit length of the optical fiber device provided in the embodiment of the present application is relatively fixed, so different lengths can correspond to different stripping efficiencies. The present application controls the stripping length of the coating layer according to the loss coefficient of the lossy core rod, while taking into account the heat dissipation efficiency, and reasonably designs the stripping length of the coating layer according to the power of the transmitted signal light, which has the advantage of flexibility and variability, and the specific numerical values are not specifically limited in the embodiment of the present application.
[0085] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.
Claims
1. An optical fiber device for online stripping of cladding light, characterized in that: include: An optical fiber body, the optical fiber body comprising a core and a cladding disposed on the core, the core and the cladding being coaxially disposed; as well as At least one lossy core rod is disposed inside the cladding, an extending direction of the lossy core rod is the same as the axial direction of the optical fiber body, and a preset distance is provided between the lossy core rod and the optical fiber core.
2. The optical fiber device according to claim 1, characterized in that: The extension direction of the lossy core rod is the same as the axial direction of the fiber core.
3. The optical fiber device according to claim 1, characterized in that: The lossy core rod is rotatably extended around the fiber core.
4. The optical fiber device according to claim 1, characterized in that: The distance between the center of the lossy core rod and the center of the core is greater than the distance between the center of the lossy core rod and the outside of the cladding.
5. The optical fiber device according to claim 1, characterized in that: The cross-sectional shape of the lossy core rod is any one of a circular shape, a D-shaped shape, and a polygonal shape.
6. The optical fiber device according to claim 1, characterized in that: The lossy core rod is doped with metal elements, and the metal elements include at least one of cobalt, iron, chromium, manganese and nickel.
7. The optical fiber device according to claim 1, further comprising a coating layer, wherein the coating layer covers the cladding layer.
8. A method for preparing an optical fiber device, characterized in that: The optical fiber device includes at least one lossy core rod, and the preparation method includes: S1. Providing an optical fiber preform and at least one lossy core rod; S2, forming at least one core rod channel inside the optical fiber preform, wherein each core rod channel is eccentrically arranged relative to the central axis of the optical fiber preform to accommodate one of the lossy core rods respectively; S3, performing a melting and shrinking process on the optical fiber preform and the lossy core rod received in the core rod channel to form a new cladding preform; S4, drawing the new cladding preform rod to obtain the optical fiber device.
9. The preparation method according to claim 8, characterized in that: The new cladding preform rod is subjected to a drawing process to obtain the optical fiber device, comprising: The direct wire drawing process is adopted to obtain the lossy core rod whose extension direction is the same as the axial direction of the new cladding preform rod.
10. The preparation method according to claim 8, characterized in that: The new cladding preform rod is subjected to a drawing process to obtain the optical fiber device, comprising: The lossy core rod is obtained by adopting a rotary wire drawing process and is arranged to be rotated and stretched around the central axis of the new cladding preform rod.