A magnetically controlled flexible CO2 laser few-mode multi-core power transfer fiber and its fabrication method

Abstract

The application provides a magnetic control flexible CO2 laser few-mode multi-core energy transmission optical fiber and a preparation method thereof. The magnetic control flexible CO2 laser few-mode multi-core energy transmission optical fiber has at least two independent laser transmission structures, a polymer cladding layer wrapped around the outer periphery of the laser transmission structure, and a magnetic outer cladding layer wrapped around the outer periphery of the polymer cladding layer, a single laser transmission channel outputs less than two modes of CO2 laser, and the adjustable controllability of the optical fiber output light field is realized, while the flexibility, robustness and actuation of the optical fiber are ensured. By controlling the fiber core diameter or the refractive index difference of the core cladding material, the single optical channel laser single-mode or few-mode output can be controlled, by controlling the number, position, distance and adding the inter-channel polymer of the optical fiber laser transmission channel, the optical crosstalk between channels can be reduced, the output light field of the optical fiber can be precisely adjusted, by controlling the magnetic particle doping amount, diameter and external magnetic field of the magnetic outer cladding layer, the movement and turning of the optical fiber can be controlled, and high-precision minimally invasive surgical medical operation is realized.

Description

Technical Field

[0001] This invention relates to the field of special optical fiber technology, and in particular to a magnetically controlled flexible CO2 laser few-mode multi-core power transmission optical fiber and its preparation method. Background Technology

[0002] Laser technology, with its high coherence, high collimation, and high intensity, is widely used in industrial processing, surgical medicine, chemical sensing, and national defense. Compared to traditional contact-based industrial processing technologies, laser processing, as a novel processing method, offers advantages such as high efficiency, safety (non-contact), no wear, and easy control. In the field of minimally invasive surgery, laser scalpel technology is gradually replacing traditional metal scalpels, electrosurgical units, and ultrasonic scalpels, providing a highly efficient, non-contact, infection-free, and low-damage surgical procedure. CO2 lasers, in particular, due to their specific operating wavelength (9.3-10.6μm) and ultra-high adjustable laser intensity, can efficiently and precisely process biological soft and hard tissues compared to other laser sources, making them the preferred laser source in surgical medicine.

[0003] In recent years, laser scalpels, which can be flexibly manipulated in extremely complex and confined environments, have gradually become a new direction in the development of minimally invasive surgery. Chinese invention patent CN207586471U discloses a vertical torsion spring CO2 laser light guide arm, which constrains the laser transmission inside by reflecting the inner wall of the metal light guide tube and adjusts the laser direction by using a reflector. However, such systems are large and heavy, and the system itself does not have flexibility, making them only suitable for superficial surgeries. Chinese invention patent CN109998671A discloses a carbon dioxide fractional laser device for surgical applications. By adding a smoke removal device to an existing carbon dioxide fractional laser instrument, a gas pump is used to continuously clear harmful fumes generated within the laser scalpel's working area, improving the operator's treatment efficiency. However, the use of a light guide arm for transmission limits the laser's application to surface surgeries, rendering it ineffective for processing in complex environments. Chinese invention patent CN113113834A discloses a mid-infrared hollow light guide with an integrated electroluminescent structure and its fabrication method. This method uses liquid-phase chemical deposition to obtain a silver-plated mid-infrared hollow light guide, resulting in low cost and high integration. The integrated electroluminescent structure emits blue-green light that can be transmitted and output synchronously with the CO2 laser within the hollow waveguide, achieving optical path indication and illumination within a certain distance. However, the light guide fabrication process is complex, difficult to operate, and lacks flexibility. Therefore, the current laser medical field still lacks a flexible, efficient, stable, and low-cost CO2 laser processing tool.

[0004] Beyond the existing requirements for flexible laser transmission tools in the field of laser medicine, efficient laser processing demands that laser transmission tools possess characteristics such as the ability to transmit high-power lasers, high laser damage threshold, and tunable single-mode or few-mode mode fields. Chinese invention patent CN111474625A discloses a multi-band transmission optical fiber. This flexible composite optical fiber combines laser transmission fiber, illumination fiber, and light-emitting fiber, enabling simultaneous ablation, illumination, and aiming. However, existing infrared materials have low laser damage thresholds, especially chalcogenide glass, the only material capable of covering the CO2 laser transmission window, whose CO2 laser damage threshold is less than 100 kW / cm². 2 Therefore, solid core-clad optical fibers cannot transmit high-power mid-infrared lasers, resulting in low laser processing efficiency. Chinese invention patent CN110333570A discloses a hollow-core energy-transmitting mid-infrared optical fiber and its fabrication method. This fiber achieves low optical loss transmission, a wide transmission range, and high-power laser transmission. Furthermore, the polymer makes the fiber lightweight, flexible, and portable, enabling portable transmission of lasers emitted by quantum cascade lasers. However, this fiber is complex to fabricate, and the hollow laser transmission fiber has a large aperture, on the order of hundreds of micrometers, resulting in multiple output laser modes, poor beam quality, and difficulty in controlling the optical field. The poor output beam quality corresponds to multiple output laser modes with uneven intensity, reducing laser processing efficiency. In addition, it also causes unevenness and excessive debris on the processed surface. Chinese invention patent CN111580230A discloses a flexible hollow optical fiber with high-power laser transmission capability. The flexible reinforcement layer comprises at least two layers, and adjacent layers in the flexible reinforcement layer and the outermost layer of the optical fiber structure have similar rheological properties to increase the overall flexibility of the fiber. However, this fiber optic transmission window is narrow, the beam output quality is poor, and it is difficult to process a neat cut interface. Alternatively, polycrystalline optical fibers can also be used to transmit high-power CO2 lasers, but due to limitations in crystal material processing technology, polycrystalline optical fibers are short in length, have a large core diameter, poor output beam quality, and high bending loss.

[0005] In recent years, multi-core power-transmitting fibers, which increase the number of laser transmission channels in a single optical fiber, have become increasingly popular. Compared to single-core solid fibers, multi-core fibers can increase the laser power threshold that the fiber can transmit by several times. Compared to hollow fibers, multi-core fibers have a simpler structure, higher strength, controllable optical field output modes, better beam output quality, and each optical channel can achieve uniform single-mode laser output. Chinese invention patent CN109678334B discloses a multi-core composite optical fiber with a chalcogenide glass core / tellurate glass cladding and its preparation method. By drawing mid-infrared optical fibers using different glass material combinations, the fiber laser transmission power threshold can be improved. However, this fiber is an all-glass structure, lacking robustness and flexibility, and optical crosstalk easily occurs between different laser transmission channels, resulting in poor beam output quality. Utility model patent CN208243925U discloses a portable infrared physiotherapy device based on an infrared fiber bundle, which transmits infrared laser through the infrared fiber bundle. Although infrared fiber bundles can increase the infrared laser transmission power threshold through multiple laser transmission channels, the large diameter of infrared fiber bundles results in insufficient device flexibility and large output beam spacing, making it difficult to achieve precise laser processing and complicating fabrication. While laser processing has advantages such as no direct contact, no noise, no vibration, and high precision, its application has long been limited by the lack of flexibility of laser transmission tools, low transmittable power threshold, and difficulty in optical field control.

[0006] Furthermore, in practical applications, achieving precise and efficient laser processing and minimally invasive surgical procedures places higher demands on the actuation and steering control of high-power CO2 laser energy transmission fibers. Patent CN 113911223 A discloses a soft robot and its control method. In complex environments, the soft robot can perform functions such as forward movement, backward movement, turning, and obstacle avoidance. However, this technology suffers from bulky components, insufficient flexibility, and a lack of efficient tissue ablation capabilities. Patent CN111663198A discloses a micro / nano magnetic fiber that can achieve efficient flexible actuation in medical settings. However, this technology lacks efficient surgical ablation capabilities, limiting its application in real-world medical settings.

[0007] Simultaneously achieving a driveable, highly flexible, high laser damage threshold, and few-mode optical field modulated multi-core power transmission fiber will be a new choice for transmission fibers in CO2 laser minimally invasive surgery. CO2 laser processing technology, as a new generation of efficient, high-precision, and low-cost processing method, suffers from problems such as insufficient flexibility of the transmission medium, low laser power threshold, poor beam output quality, and lack of driving function. These issues will be addressed by the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber of this invention. Summary of the Invention

[0008] In view of this, the present invention proposes a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber and its preparation method, which solves the problems of insufficient flexibility of the transmission medium, low laser power threshold, poor beam output quality and lack of driving function in the existing CO2 laser processing technology.

[0009] In a first aspect, the present invention provides a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, comprising:

[0010] At least two independent laser transmission structures are used to transmit few-mode CO2 lasers, and the number of CO2 laser modes output by a single laser transmission structure is less than 2.

[0011] A polymer cladding that covers the outer periphery of the laser transmission structure;

[0012] A magnetic material outer layer covers the outer periphery of the polymer outer layer.

[0013] Secondly, the present invention also provides a method for preparing the aforementioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, comprising the following steps:

[0014] Fabrication of laser transmission structure core rod;

[0015] Preparation of polymer-coated rods;

[0016] The laser transmission structure core rod and the polymer cladding rod are assembled into an optical fiber preform.

[0017] The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0018] Preparation of magnetic materials;

[0019] Magnetic materials are coated onto the surface of a flexible CO2 laser few-mode multi-core power transmission fiber.

[0020] Magnetizing a magnetic material yields a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber. The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber of this invention has the following advantages over existing technologies:

[0021] This invention relates to a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, which has at least two independent laser transmission structures. It enables high-power few-mode CO2 laser energy output through multiple laser transmission channels, with each channel outputting fewer than two modes of CO2 laser. This achieves tunability of the fiber's output optical field and modes while ensuring the fiber's flexibility and robustness. The fiber's flexible actuation and steering are controlled via a magnetic field, making it widely applicable in the field of precise CO2 laser minimally invasive surgical procedures. By controlling the core diameter of the laser transmission channels within the fiber or the refractive index difference between the core and cladding materials, the single-mode or few-mode output of a single optical channel can be controlled. By controlling the number, positional relationship, and distance of the laser transmission channels within the fiber, and by adding polymer materials between channels, optical crosstalk between channels can be reduced, allowing for precise adjustment of the fiber's output optical field and output of a high-quality laser beam. For different laser application scenarios, fiber actuation and steering can be achieved by controlling the strength and direction of the external magnetic field, enabling high-precision minimally invasive surgical procedures. By using hot drawing and coating methods, flexible multi-core optical fibers for magnetron CO2 lasers can be fabricated in a single process, achieving a length of 100 meters. The fibers can be mass-produced, with a simple process and high repeatability. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in Embodiment 1 of the present invention;

[0024] Figure 2 This is a schematic diagram of assembling a laser transmission structure core rod and a polymer cladding rod into an optical fiber preform using the extrusion method of the present invention.

[0025] Figure 3 This is a schematic diagram of the structure of the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in Embodiment 2 of the present invention;

[0026] Figure 4 This is a schematic diagram of the structure of the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in Embodiment 3 of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in Embodiment 4 of the present invention;

[0028] Figure 6This is a schematic diagram of the structure of the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in Embodiment 5 of the present invention;

[0029] Figure 7 This is a schematic diagram of the structure of the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in Embodiment 6 of the present invention;

[0030] Figure 8 This is a schematic diagram illustrating how the optical fiber preform is heated and drawn into an optical fiber in a heating furnace according to the present invention. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0032] This application provides a flexible CO2 laser multi-core power transmission fiber, comprising:

[0033] At least two independent laser transmission structures are used to transmit CO2 lasers, and the number of CO2 laser modes output by a single laser transmission structure is less than 2.

[0034] A polymer cladding is applied to the periphery of the laser transmission structure.

[0035] A magnetic material outer layer is used to cover the outer periphery of the polymer outer layer.

[0036] It should be noted that the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber of this application includes at least two independent laser transmission structures. A polymer cladding surrounds the outer periphery of the laser transmission structure, and a magnetic material cladding covers the outer periphery of the polymer cladding. The polymer cladding provides sufficient mechanical support for the entire flexible CO2 laser multi-core power transmission fiber while achieving flexibility. The laser transmission structure is located inside the fiber and is used to transmit high-power CO2 lasers, which are used for minimally invasive surgical procedures. The magnetic material cladding is located on the outermost layer of the fiber and is used to control the movement and orientation of the fiber under an applied external magnetic field.

[0037] In some embodiments, the number of CO2 laser modes output by a single laser transmission structure is less than two, specifically, the fundamental mode LP. 01 or LP 11 .

[0038] In some embodiments, the laser transmission structure is a core-cladding structure, which includes an optical fiber core and an optical fiber cladding covering the outer periphery of the optical fiber core, a polymer cladding covering the outer periphery of the optical fiber cladding, and a magnetic material cladding covering the outer periphery of the polymer cladding.

[0039] In some embodiments, the materials used for the fiber core and fiber cladding are different chalcogenide glasses or different glass materials that are transparent to the CO2 laser working window.

[0040] In the above embodiments, the fiber core and fiber cladding are made of different chalcogenide glasses or other glass materials. Specifically, chalcogenide glasses include As-Se, Sb-Se, Ge-As-Se, Ge-Sb-Se, Ge-Se, Ga-Se, Cd-Se, Ge-Se-Sn, GeSe2-Ga2Se3-KI, Ge-Se-Te, Ge-As-Se-Te, As-Se-Te, As-Te, Ge-Ga-Te, Ge-Te-Ag, Ge-Ga-Te-Cu, Ge-Te-BiI3, Ge-Te-AgI, Ge-Te-CuI, Ge-Te-Ag, etc.

[0041] In some embodiments, the polymer cladding material is a thermoplastic polymer.

[0042] In some embodiments, the thermoplastic polymer includes any one of the following: carbonate polymers (e.g., polycarbonate PC), sulfone polymers (e.g., polyether sulfone PES, polyphenylene sulfone resin PPSU), etherimide polymers (e.g., polyetherimide PEI), acrylate polymers (e.g., polymethyl methacrylate PMMA, styrene-dimethyl methacrylate copolymer SMMA), cyclic olefin copolymers (COC), polystyrene, polycarbonate, polyethylene, polypropylene, ABS, fluoropolymers, or blends of any combination thereof; the thermoplastic polymers described above have good thermal tensile properties and flexibility.

[0043] In some embodiments, the core and cladding materials of the laser transmission structure are in the same 10-1 ratio as the material used for the polymer cladding. 4 ~10 8 The viscosity range of the laser transmission structure has an overlapping temperature range. The glass transition temperature difference between the material used in the laser transmission structure and the material used in the polymer cladding is less than 50°C. This ensures that the core and cladding materials of the laser transmission structure and the material used in the polymer cladding are structurally stable, without distortion, and have stable fiber-forming properties during the hot drawing process. The drawing temperature of the material used in the laser transmission structure and the material used in the polymer cladding is 100–500°C.

[0044] In some embodiments, the magnetic material comprises a composite of magnetic particles and a substrate, wherein the magnetic particles include at least one of metallic magnetic particles, metal oxide magnetic particles, and metal alloy magnetic particles; the metallic magnetic particles include at least one of ferromagnetic particles, cobalt magnetic particles, and nickel magnetic particles; the metal oxide magnetic particles include at least one of Fe3O4 magnetic particles and γ-Fe2O3 magnetic particles; and the metal alloy magnetic particles include at least one of neodymium iron boron alloy magnetic particles, samarium cobalt alloy magnetic particles, nickel cobalt alloy magnetic particles, and iron cobalt alloy magnetic particles; and the substrate is silicone rubber.

[0045] In some embodiments, the diameter of the optical fiber core is 20–60 μm, the diameter of the optical fiber cladding is 100–200 μm, the diameter of the polymer cladding is 500–1000 μm, and the diameter of the magnetic material outer cladding is 600–2000 μm.

[0046] If a flexible CO2 laser few-mode multi-core power transmission fiber includes at least two independent laser transmission structures, then the spacing between two adjacent laser transmission structures is 100–200 μm.

[0047] In some embodiments, the magnetic particle size is 0.005–250 μm; the mass fraction of magnetic particles in the magnetic material is 0.01%–90%.

[0048] In some embodiments, the number of laser transmission structures is at least two, and the positional relationship of each laser transmission structure is a two-dimensional symmetrical structure such as parallel, triangular, quadrilateral, pentagonal, or hexagonal.

[0049] In practical applications, depending on the requirements of different processing materials and processing environments, flexible few-mode multi-core power transmission fibers with different numbers or arrangements of optical transmission channels for magnetron-controlled CO2 lasers can be selected to control the fiber output power threshold, optical field distribution, beam mode, and fiber flexibility.

[0050] Based on the same inventive concept, this application also provides a method for fabricating a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, comprising the following steps:

[0051] S1. Fabrication of laser transmission structure core rod;

[0052] S2. Prepare polymer outer coating rods;

[0053] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0054] S4. The fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0055] S5. Preparation of magnetic materials;

[0056] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0057] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0058] In some embodiments, the laser transmission structure core rod is prepared by any one of the following methods: double crucible method, melting and casting method, tube and rod method, hot stretching method, and extrusion method.

[0059] Polymer-coated rods were prepared by hot pressing or mechanical cold working.

[0060] Magnetic composite materials were prepared using a physical mixing method.

[0061] In some embodiments, the laser transmission structure core rod and the polymer outer cladding rod are assembled into an optical fiber preform using an extrusion method or a vacuum thermosetting method.

[0062] This application presents a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber with at least two independent laser transmission structures. This enables high-power CO2 laser energy output through multiple laser transmission channels, achieving tunable output optical field while ensuring fiber flexibility and robustness. The fiber's flexible actuation and steering are controlled via magnetic field control, offering broad application value in precision CO2 laser material processing and minimally invasive surgical procedures. Single-mode or few-mode laser output from individual optical channels can be controlled by adjusting the core diameter or refractive index difference of the core cladding material within the laser transmission channels. The output optical field can be precisely adjusted by controlling the number, positional relationship, and distance of the laser transmission channels. Adding polymer materials between the laser transmission channels effectively reduces optical crosstalk between channels, as all polymers are opaque in the CO2 laser band. For different laser application scenarios, fiber actuation and steering can be achieved by controlling the strength and direction of the external magnetic field, enabling high-precision processing and minimally invasive surgical procedures. The CO2 laser flexible multi-core optical fiber can be fabricated in a single process using a hot drawing and coating method. The fiber can be mass-produced with a simple process and high repeatability.

[0063] The following further illustrates the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber of this application with specific embodiments. This section further describes the content of the present invention in conjunction with specific embodiments, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in the art.

[0064] Example 1

[0065] This application provides a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, which is a dual-channel laser transmission structure, such as... Figure 1 As shown, it includes:

[0066] Two independent laser transmission structures are used to transmit few-mode CO2 lasers, and a single transmission channel outputs a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0067] The polymer cladding 110 covers the periphery of the laser transmission structure and provides sufficiently large mechanical support for the entire optical fiber.

[0068] A magnetic material outer cladding layer 120, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the applied external magnetic field.

[0069] The laser transmission structure is a core-cladding structure, which includes an optical fiber core 130 and an optical fiber cladding 140 covering the outer periphery of the optical fiber core 130, a polymer cladding 110 covering the outer periphery of the optical fiber cladding 140, and a magnetic outer cladding 120 covering the outer periphery of the polymer cladding 110.

[0070] The polymer cladding 110 is made of PPSU;

[0071] The outer layer 120 of the magnetic material is a magnetic material composed of NdFeB particles and silicone rubber.

[0072] The NdFeB particles have a diameter of 20 μm, and the mass fraction of NdFeB particles doped in the magnetic material is 40%.

[0073] The material of the fiber core layer 130 is As. 40 Se 60 The material of the fiber cladding 140 is As 38 Se 62 The core material has a refractive index of 2.776 in the 10.6μm CO2 laser band, and the cladding material has a refractive index of 2.770 in the 10.6μm band. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core 130 is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding 140 is 100μm. The fiber core 130 and fiber cladding 140 are concentric circles. The two laser transmission structures are symmetrically arranged with respect to the center of the fiber. The distance between the centers of the two fiber cores is 150μm. The diameter of the polymer cladding 110 is 600μm, and the diameter of the magnetic material outer cladding 120 is 1000μm.

[0074] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0075] S1. Fabrication of laser transmission structure core rod;

[0076] S2. Prepare polymer outer coating rods;

[0077] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0078] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0079] S5. Preparation of magnetic materials;

[0080] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0081] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0082] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material. The heating temperature is 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted. The pressure range is 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The core-to-cladding ratio of the obtained laser transmission structure core rod is 1:5, the length is 50 mm, and the diameter is 3 mm.

[0083] Step S2 involves preparing the outer polymer coating rod using hot pressing and mechanical cold working methods. Specifically: S21: A low-refractive-index polymer material layer is created using hot pressing. PPSU polymer particles are filled into a hot press mold. The mold has a rectangular groove with a length of 100mm, a width of 30mm, and a height of 30mm. The mold is placed between the upper and lower heating plates of the hot press. The hot pressing temperature is set to 300℃, and the hot pressing pressure is 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod with a length of 100mm, a width of 30mm, and a height of 30mm. S22: A round rod with a length of 100mm and a diameter of 30mm is machined using a lathe. The surface is polished to make it smooth. S23: A hole with a diameter of 5mm is drilled in one section of the round rod using a milling machine. The holes are symmetrical along the center, with a spacing of 7.5mm and a depth of 50mm. This forms the polymer coating rod.

[0084] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2 As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform 260 with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0085] In step S4, refer to Figure 8 As shown, optical fiber 262 is formed by heating and drawing an optical fiber preform 260 in a heating furnace 261 at a drawing temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. The stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material, and the process requires no protective gas atmosphere, making it simple and stable.

[0086] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB particles being 40%, to obtain a magnetic material.

[0087] Step S6 specifically involves: S61: Coating the magnetic material from step S5 onto the outer periphery of the polymer cladding using a coating method, resulting in an optical fiber diameter of 1000 μm after coating; S62: Heating in a tube furnace to solidify the magnetic material coated onto the outer periphery of the polymer cladding at a temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0088] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0089] Example 2

[0090] This application provides a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, which has a three-channel laser transmission structure, such as... Figure 3 As shown, it includes:

[0091] Three independent laser transmission structures are used to transmit few-mode CO2 lasers, and a single laser transmission channel outputs a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0092] The polymer cladding 110 covers the outer periphery of the laser transmission structure and provides sufficiently large mechanical support for the entire optical fiber.

[0093] A magnetic material outer cladding layer 120, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the applied external magnetic field.

[0094] The laser transmission structure is a core-cladding structure, which includes an optical fiber core 130 and an optical fiber cladding 140 covering the outer periphery of the optical fiber core 130, a polymer cladding 110 covering the outer periphery of the optical fiber cladding 130, and a magnetic outer cladding 120 covering the outer periphery of the polymer cladding 110.

[0095] The polymer cladding 110 is made of PPSU;

[0096] The magnetic outer layer 120 is a magnetic material made of NdFeB particles and silicone rubber, wherein the NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles in the magnetic material is 40%.

[0097] The material of the fiber core layer 130 is As. 40 Se 60 The material of the fiber cladding 140 is As 38 Se 62 The core material has a refractive index of 2.776 in the 10.6μm CO2 laser band, and the cladding material has a refractive index of 2.770 in the 10.6μm band. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core 130 is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding 140 is 100μm. The fiber core 130 and fiber cladding 140 are concentric circles. The three laser transmission structures are symmetrically arranged with respect to the center of the fiber. The distance between the centers of two adjacent fiber cores is 150μm. The diameter of the polymer cladding 110 is 600μm, and the diameter of the magnetic material outer cladding 120 is 1000μm.

[0098] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0099] S1. Fabrication of laser transmission structure core rod;

[0100] S2. Prepare polymer outer coating rods;

[0101] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0102] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0103] S5. Preparation of magnetic materials;

[0104] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0105] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0106] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material. The heating temperature is 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted. The pressure range is 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The core-to-cladding ratio of the obtained laser transmission structure core rod is 1:5, the length is 50 mm, and the diameter is 3 mm.

[0107] Step S2 involves preparing the outer polymer coating rod using hot pressing and mechanical cold working methods. Specifically: S21: A low-refractive-index polymer material layer is created using hot pressing. PPSU polymer particles are filled into a hot press mold. The mold has a rectangular groove with a length of 100mm, a width of 30mm, and a height of 30mm. The mold is placed between the upper and lower heating plates of the hot press. The hot pressing temperature is set to 300℃, and the hot pressing pressure is 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod with a length of 100mm, a width of 30mm, and a height of 30mm. S22: A round rod with a length of 100mm and a diameter of 30mm is machined using a lathe. The surface is polished to make it smooth. S23: A hole with a diameter of 5mm is drilled in one section of the round rod using a milling machine. The holes are symmetrical along the center, with a spacing of 7.5mm and a depth of 50mm. This forms the polymer coating rod.

[0108] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0109] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0110] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB particles being 40%, to obtain a magnetic material.

[0111] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0112] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0113] Example 3

[0114] This application provides a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, which has a four-channel laser transmission structure, such as... Figure 4 As shown, it includes:

[0115] Four independent laser transmission structures are used to transmit few-mode CO2 lasers, with each laser transmission channel outputting a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0116] The polymer cladding 110 covers the outer periphery of the laser transmission structure and provides sufficiently large mechanical support for the entire optical fiber.

[0117] A magnetic material outer cladding layer 120, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the applied external magnetic field.

[0118] The laser transmission structure is a core-cladding structure, which includes an optical fiber core 130 and an optical fiber cladding 140 covering the outer periphery of the optical fiber core 130, a polymer cladding 110 covering the outer periphery of the optical fiber cladding 140, and a magnetic material outer cladding 120 covering the outer periphery of the polymer cladding 110.

[0119] The polymer cladding 110 is made of PPSU;

[0120] The magnetic outer layer 120 is a magnetic material made of NdFeB particles and silicone rubber, wherein the NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles in the magnetic material is 40%.

[0121] The material of the fiber core layer 130 is As. 40 Se 60 The material of the fiber cladding 140 is As 38 Se 62 The core material has a refractive index of 2.776 in the 10.6μm CO2 laser band, and the cladding material has a refractive index of 2.770 in the 10.6μm band. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core 130 is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding 140 is 100μm. The fiber core 130 and fiber cladding 140 are concentric circles. The four laser transmission structures are symmetrically arranged with respect to the center of the fiber. The distance between the centers of two adjacent fiber cores is 150μm. The diameter of the polymer cladding 110 is 600μm, and the diameter of the magnetic material outer cladding 120 is 1000μm.

[0122] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0123] S1. Fabrication of laser transmission structure core rod;

[0124] S2. Prepare polymer outer coating rods;

[0125] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0126] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0127] S5. Preparation of magnetic materials;

[0128] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0129] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0130] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material, with a heating temperature of 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted, with a pressure range of 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The obtained laser transmission structure core rod has a core-to-cladding ratio of 1:5, a length of 50 mm, and a diameter of 3 mm.

[0131] Step S2 involves preparing the outer polymer coating rod using hot pressing and mechanical cold working methods. Specifically: S21: A low-refractive-index polymer material layer is created using hot pressing. PPSU polymer particles are filled into a hot press mold. The mold has a rectangular groove with a length of 100mm, a width of 30mm, and a height of 30mm. The mold is placed between the upper and lower heating plates of the hot press. The hot pressing temperature is set to 300℃, and the hot pressing pressure is 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod with a length of 100mm, a width of 30mm, and a height of 30mm. S22: A round rod with a length of 100mm and a diameter of 30mm is machined using a lathe. The surface is polished to make it smooth. S23: A hole with a diameter of 5mm is drilled in one section of the round rod using a milling machine. The holes are symmetrical along the center, with a spacing of 7.5mm and a depth of 50mm. This forms the polymer coating rod.

[0132] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0133] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0134] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB being 40%, to obtain a magnetic material.

[0135] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0136] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0137] Example 4

[0138] This application provides a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, which has a five-channel laser transmission structure, such as... Figure 5 As shown, it includes:

[0139] Five independent laser transmission structures are used to transmit few-mode CO2 lasers, with each laser transmission channel outputting a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0140] The polymer cladding 110 covers the outer periphery of the laser transmission structure and provides sufficiently large mechanical support for the entire optical fiber.

[0141] A magnetic material outer cladding layer 120, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the applied external magnetic field.

[0142] The laser transmission structure is a core-cladding structure, which includes an optical fiber core 130 and an optical fiber cladding 140 covering the outer periphery of the optical fiber core 130, a polymer cladding 110 covering the outer periphery of the optical fiber cladding 140, and a magnetic material outer cladding 120 covering the outer periphery of the polymer cladding 110.

[0143] The polymer cladding 110 is made of PPSU;

[0144] The outer cladding layer 120 of the magnetic material is a magnetic composite material made of NdFeB particles and silicone rubber, wherein the NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles doped in the magnetic material is 40%.

[0145] The material of the fiber core layer 130 is As. 40 Se 60 The material of the fiber cladding 140 is As 38 Se 62 The core material has a refractive index of 2.776 in the 10.6μm CO2 laser band, and the cladding material has a refractive index of 2.770 in the 10.6μm band. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core 120 is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding 140 is 100μm. The fiber core 130 and fiber cladding 140 are concentric circles. One of the five laser transmission structures is located at the center of the fiber (i.e., the center of the middle laser transmission structure coincides with the circle of the fiber). The other four laser transmission structures are symmetrically arranged with respect to the center of the fiber. The distance between the centers of two adjacent fiber cores is 150μm. The diameter of the polymer cladding 110 is 600μm, and the diameter of the magnetic material outer cladding 120 is 1000μm.

[0146] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0147] S1. Fabrication of laser transmission structure core rod;

[0148] S2. Prepare polymer outer coating rods;

[0149] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0150] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0151] S5. Preparation of magnetic materials;

[0152] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0153] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0154] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material. The heating temperature is 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted. The pressure range is 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The core-to-cladding ratio of the obtained laser transmission structure core rod is 1:5, the length is 50 mm, and the diameter is 3 mm.

[0155] Step S2 involves preparing the outer polymer cladding rod using a hot-pressing and mechanical cold-working method. Specifically: S21: A low-refractive-index polymer material layer is fabricated using a hot-pressing method. PPSU polymer particles are filled into a hot-pressing mold with a rectangular groove measuring 100mm in length, 30mm in width, and 30mm in height. The mold is placed between the upper and lower heating plates of the hot-pressing machine, and the hot-pressing temperature is set to 300℃ and the hot-pressing pressure to 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod measuring 100mm in length, 30mm in width, and 30mm in height. S22: A round rod measuring 100mm in length and 30mm in diameter is machined using a lathe, and its surface is polished to make it smooth. S23: A 5mm diameter hole is drilled in one section of the round rod using a milling machine. One hole is located at the center of the optical fiber, and the other holes are symmetrically distributed along the center of the optical fiber. The hole spacing is 7.5mm, and the depth is 50mm, thus forming the polymer cladding rod.

[0156] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0157] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0158] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB being 40%, to obtain a magnetic material.

[0159] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0160] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0161] Example 5

[0162] This application provides a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, which has a six-channel laser transmission structure, such as... Figure 6 As shown, it includes:

[0163] Six independent laser transmission structures are used to transmit few-mode CO2 lasers, with each laser transmission channel outputting a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0164] The polymer cladding 110 covers the outer periphery of the laser transmission structure and provides sufficiently large mechanical support for the entire optical fiber.

[0165] A magnetic material outer cladding layer 120, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the applied external magnetic field.

[0166] The laser transmission structure is a core-cladding structure, which includes an optical fiber core 130 and an optical fiber cladding 140 covering the outer periphery of the optical fiber core 130, a polymer cladding 110 covering the outer periphery of the optical fiber cladding 140, and a magnetic material outer cladding 120 covering the outer periphery of the polymer cladding 110.

[0167] The polymer cladding 110 is made of PPSU;

[0168] The magnetic outer layer 120 is a magnetic material made of NdFeB particles and silicone rubber, wherein the NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles in the magnetic material is 40%.

[0169] The material of the fiber core layer 130 is As. 40 Se 60 The material of the fiber cladding 140 is As 38 Se 62 The refractive index of the core material in the 10.6μm CO2 laser band is 2.776, and the refractive index of the cladding material in the 10.6μm band is 2.770. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core 130 is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding 140 is 100μm. The fiber core 130 and fiber cladding 140 are concentric circles. One of the six laser transmission structures is located at the center of the fiber (i.e., the center of the laser transmission structure in the middle coincides with the circle of the fiber). The other five laser transmission structures are symmetrically distributed in a regular pentagon relative to the center of the fiber. The distance between the centers of two adjacent fiber cores is 150μm. The diameter of the polymer cladding 110 is 600μm, and the diameter of the magnetic material outer cladding 120 is 1000μm.

[0170] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0171] S1. Fabrication of laser transmission structure core rod;

[0172] S2. Prepare polymer outer coating rods;

[0173] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0174] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0175] S5. Preparation of magnetic materials;

[0176] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0177] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0178] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material. The heating temperature is 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted. The pressure range is 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The core-to-cladding ratio of the obtained laser transmission structure core rod is 1:5, the length is 50 mm, and the diameter is 3 mm.

[0179] Step S2 involves preparing the outer polymer cladding rod using a hot-pressing and mechanical cold-working method. Specifically: S21: A low-refractive-index polymer material layer is fabricated using a hot-pressing method. PPSU polymer particles are filled into a hot-pressing mold with a rectangular groove measuring 100mm in length, 30mm in width, and 30mm in height. The mold is placed between the upper and lower heating plates of the hot-pressing machine, and the hot-pressing temperature is set to 300℃ and the hot-pressing pressure to 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod measuring 100mm in length, 30mm in width, and 30mm in height. S22: A round rod measuring 100mm in length and 30mm in diameter is machined using a lathe, and its surface is polished to make it smooth. S23: A 5mm diameter hole is drilled in one section of the round rod using a milling machine. One hole is located at the center of the optical fiber, and the other holes are symmetrically distributed in a regular pentagonal pattern along the center of the optical fiber. The hole spacing is 7.5mm, and the depth is 50mm, thus forming the polymer cladding rod.

[0180] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0181] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0182] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB being 40%, to obtain a magnetic material.

[0183] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0184] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0185] Example 6

[0186] This application provides a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, which has a seven-channel laser transmission structure, such as... Figure 7 As shown, it includes:

[0187] Seven independent laser transmission structures are used to transmit few-mode CO2 lasers, with each laser transmission channel outputting a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0188] The polymer cladding 110 covers the outer periphery of the laser transmission structure and provides sufficiently large mechanical support for the entire optical fiber.

[0189] A magnetic material outer cladding layer 120, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the applied external magnetic field.

[0190] The laser transmission structure is a core-cladding structure, which includes an optical fiber core 130 and an optical fiber cladding 140 covering the outer periphery of the optical fiber core 130, a polymer cladding 110 covering the outer periphery of the optical fiber cladding 140, and a magnetic outer cladding 120 covering the outer periphery of the polymer cladding 110.

[0191] The polymer cladding 110 is made of PPSU;

[0192] The outer cladding layer 120 of the magnetic material is a magnetic material composed of NdFeB particles and silicone rubber. The NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles in the magnetic material is 40%.

[0193] The material of the fiber core layer 130 is As. 40 Se 60 The material of the fiber cladding 140 is As 38 Se 62 The refractive index of the core material in the 10.6μm CO2 laser band is 2.776, and the refractive index of the cladding material in the 10.6μm band is 2.770. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core 130 is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding 140 is 100μm. The fiber core 130 and fiber cladding 140 are concentric circles. One of the seven laser transmission structures is located at the center of the fiber (i.e., the center of the laser transmission structure in the middle coincides with the circle of the fiber). The other six laser transmission structures are symmetrically distributed in a regular hexagon relative to the center of the fiber. The distance between the centers of two adjacent fiber cores is 150μm. The diameter of the polymer cladding 110 is 600μm, and the diameter of the magnetic material outer cladding 120 is 1000μm.

[0194] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0195] S1. Fabrication of laser transmission structure core rod;

[0196] S2. Prepare polymer outer coating rods;

[0197] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0198] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0199] S5. Preparation of magnetic materials;

[0200] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0201] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0202] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material, with a heating temperature of 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted, with a pressure range of 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The obtained laser transmission structure core rod has a core-to-cladding ratio of 1:5, a length of 50 mm, and a diameter of 3 mm.

[0203] Step S2 involves preparing the outer polymer cladding rod using a hot-pressing and mechanical cold-working method. Specifically: S21: A low-refractive-index polymer material layer is fabricated using a hot-pressing method. PPSU polymer particles are filled into a hot-pressing mold with a rectangular groove measuring 100mm in length, 30mm in width, and 30mm in height. The mold is placed between the upper and lower heating plates of the hot-pressing machine, and the hot-pressing temperature is set to 300℃ and the hot-pressing pressure to 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod measuring 100mm in length, 30mm in width, and 30mm in height. S22: A round rod measuring 100mm in length and 30mm in diameter is machined using a lathe, and its surface is polished to make it smooth. S23: A 5mm diameter hole is drilled in one section of the round rod using a milling machine. One hole is located at the center of the optical fiber, and the other holes are symmetrically distributed in a regular hexagonal pattern along the center of the optical fiber. The hole spacing is 7.5mm, and the depth is 50mm, thus forming the polymer cladding rod.

[0204] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0205] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0206] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB being 40%, to obtain a magnetic material.

[0207] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0208] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0209] Example 7

[0210] The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in this application embodiment has a seven-channel laser transmission structure, including:

[0211] Seven independent laser transmission structures are used to transmit few-mode CO2 lasers, with each laser transmission channel outputting a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0212] A polymer cladding, which covers the outer periphery of the laser transmission structure, is used to provide sufficiently large mechanical support for the entire optical fiber.

[0213] A magnetic material cladding layer, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the application of an external magnetic field.

[0214] The laser transmission structure is a core-cladding structure, which includes an optical fiber core and an optical fiber cladding covering the outer periphery of the optical fiber core. A polymer cladding covers the outer periphery of the optical fiber cladding, and a magnetic material cladding covers the outer periphery of the polymer cladding.

[0215] The polymer cladding material is PPSU;

[0216] The magnetic outer layer is a magnetic material made of NdFeB particles and silicone rubber, wherein the NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles in the magnetic material is 40%.

[0217] The fiber core is made of Ge 20 As 20 Te 45 Se 15 The material of the optical fiber cladding is Ge 20 As 20 Te 44 Se 16 The refractive index of the core material in the 10.6μm CO2 laser band is 3.131, and the refractive index of the cladding material in the 10.6μm band is 3.116. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.015. The diameter of the fiber core is 30μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding is 150μm. The fiber core and fiber cladding are concentric circles. One of the seven laser transmission structures is located at the center of the fiber (i.e., the center of the laser transmission structure in the middle coincides with the circle of the fiber). The other six laser transmission structures are symmetrically distributed in a regular hexagon relative to the center of the fiber. The distance between the centers of two adjacent fiber cores is 225μm. The diameter of the polymer cladding is 900μm, and the diameter of the magnetic material cladding is 1500μm.

[0218] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0219] S1. Fabrication of laser transmission structure core rod;

[0220] S2. Prepare polymer outer coating rods;

[0221] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0222] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0223] S5. Preparation of magnetic materials;

[0224] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0225] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0226] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material at a temperature of 200-500℃; S13: The heating temperature is lowered, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted to a pressure range of 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The core-to-cladding ratio of the obtained laser transmission structure core rod is 1:5, its length is 50 mm, and its diameter is 3 mm.

[0227] Step S2 involves preparing the outer polymer cladding rod using a hot-pressing and mechanical cold-working method. Specifically: S21: A low-refractive-index polymer material layer is fabricated using a hot-pressing method. PPSU polymer particles are filled into a hot-pressing mold with a rectangular groove measuring 100mm in length, 30mm in width, and 30mm in height. The mold is placed between the upper and lower heating plates of the hot-pressing machine, and the hot-pressing temperature is set to 300℃ and the hot-pressing pressure to 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod measuring 100mm in length, 30mm in width, and 30mm in height. S22: A round rod measuring 100mm in length and 30mm in diameter is machined using a lathe, and its surface is polished to make it smooth. S23: A 5mm diameter hole is drilled in one section of the round rod using a milling machine. One hole is located at the center of the optical fiber, and the other holes are symmetrically distributed in a regular hexagonal pattern along the center of the optical fiber. The hole spacing is 6mm, and the depth is 50mm, thus forming the polymer cladding rod.

[0228] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0229] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0230] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB being 40%, to obtain a magnetic material.

[0231] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0232] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0233] Example 8

[0234] The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in this application embodiment has a seven-channel laser transmission structure, including:

[0235] Seven independent laser transmission structures are used to transmit few-mode CO2 lasers, with each laser transmission channel outputting a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0236] A polymer cladding, which covers the outer periphery of the laser transmission structure, is used to provide sufficiently large mechanical support for the entire optical fiber.

[0237] A magnetic material cladding layer, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the application of an external magnetic field.

[0238] The laser transmission structure is a core-cladding structure, which includes an optical fiber core and an optical fiber cladding covering the outer periphery of the optical fiber core. A polymer cladding covers the outer periphery of the optical fiber cladding, and a magnetic material cladding covers the outer periphery of the polymer cladding.

[0239] The polymer coating material is a blend of PPSU and PVDF. Specifically, commercial PPSU and PVDF particles are mixed physically or chemically to obtain the PPSU and PVDF blend, with PVDF having a specific gravity of 10-40 wt%. The blend and the laser transmission structure mandrel are coated at a ratio of 10... 4 -10 8 The viscosity range of poise has an overlapping region with the temperature range;

[0240] The magnetic outer layer is a magnetic material made of NdFeB particles and silicone rubber, wherein the NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles in the magnetic material is 40%.

[0241] The material of the fiber core is As 40 Se 60 The material of the optical fiber cladding, As 38 Se 62 The refractive index of the core material in the 10.6μm CO2 laser band is 2.776, and the refractive index of the cladding material in the 10.6μm band is 2.770. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding is 100μm. The fiber core and fiber cladding are concentric circles. One of the seven laser transmission structures is located at the center of the fiber (i.e., the center of the laser transmission structure in the middle coincides with the circle of the fiber). The other six laser transmission structures are symmetrically distributed in a regular hexagon relative to the center of the fiber. The distance between the centers of two adjacent fiber cores is 150μm. The diameter of the polymer cladding is 600μm, and the diameter of the magnetic material cladding is 1500μm.

[0242] This application also provides a method for fabricating the above-mentioned magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0243] S1. Fabrication of laser transmission structure core rod;

[0244] S2. Prepare polymer outer coating rods;

[0245] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0246] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0247] S5. Preparation of magnetic materials;

[0248] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0249] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0250] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material, with a heating temperature of 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted, with a pressure range of 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The obtained laser transmission structure core rod has a core-to-cladding ratio of 1:5, a length of 50 mm, and a diameter of 3 mm.

[0251] Step S2 involves preparing the outer polymer outer coating rod using hot pressing and mechanical cold processing. Specifically: S21: A low-refractive-index polymer material layer is fabricated using a hot-pressing method. PPSU and PVDF blended polymer particles are filled into a hot-pressing mold. The mold has a rectangular groove with a length of 100mm, a width of 30mm, and a height of 30mm. The mold is placed between the upper and lower heating plates of the hot press, and the hot-pressing temperature is set to 290℃ and the hot-pressing pressure is 10MPa. The PPSU and PVDF blended polymer particles are hot-pressed into a rectangular rod with a length of 100mm, a width of 30mm, and a height of 30mm. S22: A round rod with a length of 100mm and a diameter of 30mm is machined using a lathe, and the surface is polished to make it smooth. S23: A hole with a diameter of 5mm is drilled in one section of the round rod using a milling machine. One hole is located at the center of the optical fiber, and the other holes are symmetrically distributed in a regular hexagonal pattern along the center of the optical fiber. The hole spacing is 6mm and the depth is 50mm, which is the polymer outer cladding rod.

[0252] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using an extrusion method. The extrusion method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Figure 2 As shown, specifically: S31: The laser transmission structure core rod is embedded in the outer polymer cladding rod using a tube-rod method to obtain an assembly 210; S32: The assembly is placed in an alloy mold cavity 230, which is an external atmospheric furnace 220. The inner diameter of the alloy mold cavity is 25-26mm. Above it is an alloy piston 240 that can be pushed up and down and a vacuum interface 250. Below it is a gradient extrusion port with a bottom port diameter of 10mm; S33: The vacuum interface above the alloy mold cavity is opened, and the vacuum pump evacuates the cavity to a vacuum degree of 1-10Pa; S34: The atmospheric furnace is turned on, and the temperature is set to 200-500℃; S35: After the assembly softens, the piston rod is pushed down, and the load is controlled at 5-10Mpa and the pushing speed is 1mm / min. Finally, an optical fiber preform with a diameter of 8-10mm and a length of 40-100cm is obtained, with a laser transmission structure core rod on the inside and a polymer cladding on the outside.

[0253] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0254] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB being 40%, to obtain a magnetic material.

[0255] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0256] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0257] Example 9

[0258] The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber provided in this application embodiment has a seven-channel laser transmission structure, including:

[0259] Seven independent laser transmission structures are used to transmit few-mode CO2 lasers, with each laser transmission channel outputting a single-mode CO2 laser to achieve material processing or biological tissue ablation.

[0260] A polymer cladding, which covers the outer periphery of the laser transmission structure, is used to provide sufficiently large mechanical support for the entire optical fiber.

[0261] A magnetic material cladding layer, which covers the outer periphery of the polymer cladding layer, is used to control the movement and orientation of the optical fiber under the application of an external magnetic field.

[0262] The laser transmission structure is a core-cladding structure, which includes an optical fiber core and an optical fiber cladding covering the outer periphery of the optical fiber core. A polymer cladding covers the outer periphery of the optical fiber cladding, and a magnetic material cladding covers the outer periphery of the polymer cladding.

[0263] The polymer cladding material is PPSU polymer;

[0264] The outer cladding material of the magnetic material is a magnetic material composed of NdFeB particles and silicone rubber, wherein the NdFeB particles have a particle size of 20 μm and the mass fraction of NdFeB particles in the magnetic material is 40%.

[0265] The material of the fiber core is As 40 Se 60 The material of the optical fiber cladding, As 38 Se 62 The refractive index of the core material in the 10.6μm CO2 laser band is 2.776, and the refractive index of the cladding material in the 10.6μm band is 2.770. The difference in refractive index between the core and cladding materials in the CO2 laser band is less than 0.006. The diameter of the fiber core is 20μm, which meets the conditions for single-mode laser transmission. The diameter of the fiber cladding is 100μm. The fiber core and fiber cladding are concentric circles. One of the seven laser transmission structures is located at the center of the fiber (i.e., the center of the laser transmission structure in the middle coincides with the circle of the fiber). The other six laser transmission structures are symmetrically distributed in a regular hexagon relative to the center of the fiber. The distance between the centers of two adjacent fiber cores is 150μm. The diameter of the polymer cladding is 600μm, and the diameter of the magnetic material cladding is 1000μm.

[0266] This application also provides a method for fabricating the above-mentioned flexible CO2 laser few-mode multi-core power transmission fiber, including the following steps:

[0267] S1. Fabrication of laser transmission structure core rod;

[0268] S2. Prepare polymer outer coating rods;

[0269] S3. Assemble the laser transmission structure core rod and the polymer outer cladding rod into an optical fiber preform.

[0270] S4. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber.

[0271] S5. Preparation of magnetic materials;

[0272] S6. Coat the surface of a flexible CO2 laser few-mode multi-core power transmission fiber with magnetic material.

[0273] S7. Magnetize the magnetic material to obtain a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0274] Specifically, the method for preparing the laser transmission structure core rod in step S1 is as follows: The laser transmission structure core rod is prepared using a double crucible method. Specifically: S11: The core layer and cladding material of the laser transmission structure are placed in a quartz double crucible with an inert gas environment and a heating furnace, and with internal and external inert gas pressure devices above; S12: The double crucible and the internal material are heated to completely melt and homogenize the core layer and cladding material. The heating temperature is 200-500℃; S13: The heating temperature is reduced, the viscosity of the core layer and cladding material is increased, and the internal and external inert gas pressure devices are adjusted. The pressure range is 0-500 kPa. Finally, the laser transmission structure core rod is obtained at the outlet of the double crucible. The core-to-cladding ratio of the obtained laser transmission structure core rod is 1:5, the length is 50 mm, and the diameter is 3 mm.

[0275] Step S2 involves preparing the outer polymer cladding rod using a hot-pressing and mechanical cold-working method. Specifically: S21: A low-refractive-index polymer material layer is fabricated using a hot-pressing method. PPSU polymer particles are filled into a hot-pressing mold with a rectangular groove measuring 100mm in length, 30mm in width, and 30mm in height. The mold is placed between the upper and lower heating plates of the hot-pressing machine, and the hot-pressing temperature is set to 290℃ and the hot-pressing pressure to 10MPa. The PPSU polymer particles are hot-pressed into a rectangular rod measuring 100mm in length, 30mm in width, and 30mm in height. S22: A round rod measuring 100mm in length and 30mm in diameter is machined using a lathe, and its surface is polished to make it smooth. S23: A 5mm diameter hole is drilled in one section of the round rod using a milling machine. One hole is located at the center of the optical fiber, and the other holes are symmetrically distributed in a regular hexagonal pattern along the center of the optical fiber. The hole spacing is 7.5mm, and the depth is 50mm, thus forming the polymer cladding rod.

[0276] Step S3 assembles the laser transmission structure core rod and the polymer cladding rod into an optical fiber preform using a vacuum thermosetting method. The vacuum thermosetting method ensures a tight bond between the laser transmission structure core rod and the polymer cladding, preventing oxidation and degradation of the core rod glass during the drawing process, which would affect the optical performance of the fiber. Specifically: S31: The laser transmission structure core rod is embedded into the outer polymer cladding rod using a tube-rod method; S32: The assembly is placed in a vacuum tube furnace equipped with a vacuum interface, and the vacuum pump is turned on, achieving a vacuum level of 10... -4 Pa; S33: Set the temperature program, the thermosetting temperature is 150-400℃, and the thermosetting time is 15min to obtain an optical fiber preform with a laser transmission structure core on the inside and a polymer cladding on the outside.

[0277] In step S4, the optical fiber preform is heated and drawn into an optical fiber in a furnace at a temperature of 300-400℃, a feeding speed of 0.1-1 mm / min, and a pulling speed of 0.1-1 m / min. A stable polymer material protects the water- and oxygen-sensitive chalcogenide glass material. The process requires no protective gas atmosphere and is simple and stable.

[0278] Step S5 involves uniformly mixing 20μm NdFeB particles with organosilicon rubber liquid using a physical mixing method, with the mass fraction of NdFeB being 40%, to obtain a magnetic material.

[0279] In step S6, specifically: S61: The magnetic material from step S5 is coated onto the outer periphery of the polymer cladding by a coating method, and the diameter of the optical fiber after coating is 1000 μm; S62: The magnetic material coated onto the outer periphery of the polymer cladding is solidified in a tube furnace at a heating temperature of 100°C, thereby obtaining a flexible CO2 laser few-mode multi-core power transmission optical fiber coated with magnetic material.

[0280] Step 7 involves magnetizing the flexible CO2 laser few-mode multi-core power transmission fiber coated with magnetic material in a magnetizer to obtain the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

[0281] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber, characterized in that, include: At least two independent laser transmission structures are used to transmit few-mode CO2 lasers, and the number of CO2 laser modes output by a single laser transmission structure is less than 2. A polymer cladding that covers the outer periphery of the laser transmission structure; A magnetic material outer layer covers the outer periphery of the polymer outer layer; The magnetic material comprises a composite of magnetic particles and a substrate; The substrate includes silicone rubber; The magnetic material cladding is used to control the movement and direction of the optical fiber under the applied external magnetic field.

2. The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in claim 1, characterized in that, The laser transmission structure is a core-cladding structure, which includes an optical fiber core and an optical fiber cladding covering the outer periphery of the optical fiber core. The polymer cladding covers the outer periphery of the optical fiber cladding, and a magnetic material cladding covers the outer periphery of the polymer cladding.

3. The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in claim 2, characterized in that, The materials used for the fiber core and fiber cladding are different chalcogenide glasses or different glass materials that are transparent to the CO2 laser working window; The polymer coating material is a thermoplastic polymer.

4. The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in claim 3, characterized in that, The thermoplastic polymer includes any one of carbonate polymers, sulfone polymers, etherimide polymers, acrylate polymers, styrene-dimethyl methacrylate copolymers, cyclic olefin copolymers, polystyrene, polycarbonate, polyethylene, polypropylene, ABS, and fluoropolymers, or blends of any combination of carbonate polymers, sulfone polymers, etherimide polymers, acrylate polymers, styrene-dimethyl methacrylate copolymers, cyclic olefin copolymers, polystyrene, polycarbonate, polyethylene, polypropylene, ABS, and fluoropolymers.

5. The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in claim 1, characterized in that, The material used in the laser transmission structure is similar to the material used in the polymer cladding at 10... 4 ~10 8 The viscosity range of the optical transmission structure has an overlapping temperature range, and the glass transition temperature difference between the material used in the optical transmission structure and the material used in the polymer coating is less than 50 °C.

6. The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in claim 1, characterized in that, The magnetic particles include at least one of metallic magnetic particles, metallic oxide magnetic particles, and metallic alloy magnetic particles. The metallic magnetic particles include at least one of ferromagnetic particles, cobalt magnetic particles, and nickel magnetic particles; The metal oxide magnetic particles include at least one of Fe3O4 magnetic particles and γ-Fe2O3 magnetic particles. The metal alloy magnetic particles include at least one of neodymium iron boron alloy magnetic particles, samarium cobalt alloy magnetic particles, nickel cobalt alloy magnetic particles, and iron cobalt alloy magnetic particles; The magnetic particles have a particle size of 0.005~250 μm; The magnetic material contains magnetic particles at a mass fraction of 0.01% to 90%.

7. The magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in claim 2, characterized in that, The diameter of the optical fiber core is 20~60 μm, the diameter of the optical fiber cladding is 100~200 μm, the diameter of the polymer cladding is 500~1000 μm, and the diameter of the magnetic material outer cladding is 600~2000 μm. If the magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber includes at least two independent laser transmission structures, then the distance between the centers of two adjacent laser transmission structures is 100~200 μm.

8. A method for fabricating a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Fabrication of laser transmission structure core rod; Preparation of polymer-coated rods; The laser transmission structure core rod and the polymer cladding rod are assembled into an optical fiber preform. The optical fiber preform is thermally drawn to obtain a flexible CO2 laser few-mode multi-core power transmission fiber. Preparation of magnetic materials; Magnetic materials are coated onto the surface of a flexible CO2 laser few-mode multi-core power transmission fiber. Magnetizing magnetic materials yields a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber.

9. The method for fabricating a magnetically controlled flexible CO2 laser few-mode multi-core power transmission fiber as described in claim 8, characterized in that, Laser transmission structure core rods were prepared using any one of the following methods: double crucible method, melting and casting method, tube and rod method, hot stretching method, and extrusion method. Polymer-coated rods were prepared by hot pressing or mechanical cold working. The laser transmission structure core rod and the polymer outer cladding rod are assembled into an optical fiber preform using extrusion or vacuum thermosetting methods. Magnetic materials were prepared using a physical mixing method.

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