CN114859469A - Welding method of aluminum fluoride-based glass fiber and quartz fiber - Google Patents

Welding method of aluminum fluoride-based glass fiber and quartz fiber Download PDF

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Publication number
CN114859469A
CN114859469A CN202210594218.9A CN202210594218A CN114859469A CN 114859469 A CN114859469 A CN 114859469A CN 202210594218 A CN202210594218 A CN 202210594218A CN 114859469 A CN114859469 A CN 114859469A
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optical fiber
fiber
aluminum fluoride
based glass
fusion
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王鹏飞
王立媛
王顺宾
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Harbin Engineering University
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Harbin Engineering University
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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/255—Splicing of light guides, e.g. by fusion or bonding
    • G02B6/2551—Splicing of light guides, e.g. by fusion or bonding using thermal methods, e.g. fusion welding by arc discharge, laser beam, plasma torch
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/24—Coupling light guides
    • G02B6/255—Splicing of light guides, e.g. by fusion or bonding
    • G02B6/2555—Alignment or adjustment devices for aligning prior to splicing
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
    • Y02P40/57—Improving the yield, e-g- reduction of reject rates

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Mechanical Coupling Of Light Guides (AREA)

Abstract

The invention discloses a fusion welding method of an aluminum fluoride-based glass fiber and a quartz fiber, and belongs to the technical field of all-fiber lasers. Firstly, end face treatment is carried out on two optical fibers, the two optical fibers to be welded with smooth and flat end faces are respectively fixed in optical fiber clamps on the left side and the right side of an optical fiber welding machine, then alignment operation is carried out on fiber cores of the two optical fibers, and then optical fiber welding parameters are set. Because the transition temperature of the quartz optical fiber is higher than that of the aluminum fluoride-based glass optical fiber, the heating fire head position is biased to the quartz optical fiber by adopting an asymmetric fusion mode, so that the low-loss and high-strength fusion of the two optical fibers is realized. The optical fiber welding method provided by the invention has the advantages that the welding success rate is 90%, the average loss of a welding point is 0.1dB, the average tensile resistance is 200g, the stability and the reliability of the optical fiber welding method in practical application are improved, and the optical fiber welding method can be used for developing a full-fiber high-power intermediate infrared laser.

Description

Welding method of aluminum fluoride-based glass fiber and quartz fiber
Technical Field
The invention belongs to the technical field of all-fiber lasers, and particularly relates to a fusion welding method of an aluminum fluoride-based glass fiber and a quartz fiber.
Background
The aluminum fluoride-based glass fiber has high mechanical strength, water resistance, acid resistance, transition temperature, thermal stability and chemical stability as a novel fluoride optical fiber, and has great application potential in a mid-infrared fiber laser because the aluminum fluoride-based glass fiber has the excellent properties.
A great important direction for the development of fiber laserI.e. to increase the laser output power. In 2018, Jia et al in Ho doping 3+ The aluminum fluoride-based glass fiber realizes 2.826-micron mid-infrared laser output, the maximum output power is 57mW, and the slope efficiency is 5.1%. In 2020, Wang et al at Ho 3+ /Pr 3+ Laser output of 2.9 μm was achieved in the co-doped aluminum fluoride-based glass fiber with a maximum output power of 173mW and a slope efficiency of 10.3%. In 2020, Zhang et al at Ho 3+ /Pr 3+ Laser output of 2.865 μm was achieved in the co-doped aluminum fluoride-based glass fiber with a maximum output power of 207mW and a slope efficiency of 11.4%. In 2021, Liu et al at Ho 3+ /Pr 3+ The co-doped aluminum fluoride-based glass fiber realizes laser output of 3 mu m, the maximum output power is 1.02W, and the slope efficiency is 10.7%.
The above-listed examples adopt a spatial coupling mode in coupling the laser of the pump laser to the aluminum fluoride-based glass fiber, which is difficult and low in coupling efficiency, and limits the improvement of the output laser power. The whole optical path is unstable, which not only affects the laser output power, but also affects the laser conversion efficiency. The space coupling mode reduces the integration level of the system, and the system is difficult to move again on the original basis after being formed, which is not beneficial to practical application.
Therefore, based on the above problems, we propose to fuse an aluminum fluoride-based glass fiber with a quartz fiber to obtain a low-loss, high-strength fusion point and improve the stability and reliability of the system, and the fusion method is described in detail in this patent. The invention discloses a fusion welding method of an aluminum fluoride-based glass fiber and a quartz fiber, which has a very important promotion effect on the development of a full-fiber laser.
Disclosure of Invention
The invention aims to provide a method for welding an aluminum fluoride-based glass optical fiber and a quartz optical fiber, wherein a welding point has lower loss and higher strength.
The invention is realized by the following steps:
firstly, carrying out end face treatment on an aluminum fluoride-based glass optical fiber and a quartz optical fiber, respectively fixing the aluminum fluoride-based glass optical fiber and the quartz optical fiber with smooth and flat end faces in optical fiber clamps at the left side and the right side of a Vytran large-fiber-core optical fiber fusion splicer, and then carrying out alignment operation on the aluminum fluoride-based glass optical fiber and the quartz optical fiber; because of the transition temperature of quartz optical fiber is higher than the transition temperature of aluminium fluoride base glass optical fiber, so adopt asymmetric butt fusion mode, heating flame position offset in quartz optical fiber, its heating temperature should be less than the softening temperature of quartz optical fiber, is higher than the softening temperature of aluminium fluoride base glass optical fiber, and then sets for the optical fiber butt fusion parameter, realizes aluminium fluoride base glass optical fiber and the low-loss of quartz optical fiber, high strength butt fusion, final measurement splice point loss and intensity.
Furthermore, the core diameter of the aluminum fluoride-based optical fiber is 7-12 μm, the cladding diameter is 230-240 μm, and the length is 1.2 m; the quartz fiber is a corning SMF28 single-mode fiber, the diameter of a fiber core of the fiber is 8.3 mu m, and the diameter of a cladding of the fiber is 125 mu m.
Furthermore, the end face treatment comprises three links of peeling, cleaning and cutting.
Furthermore, the model of the Vytran large-fiber-core optical fiber fusion splicer is GPX3400, and the Vytran large-fiber-core optical fiber fusion splicer comprises a melting furnace assembly, an optical fiber clamping device, a CCD camera for imaging, a host and a display which are pre-installed with control software, and a reflector tower for side and end imaging.
Further, the lower fiber clamping inserts used in the left and right fiber clamps are VHF250 and VHF160 respectively, the VHF250 is suitable for the fibers with the diameters of 177-320 mu m, and the VHF160 is suitable for the fibers with the diameters of 112-208 mu m.
Further, the alignment operation is to align the fiber core of the aluminum fluoride-based glass optical fiber and the fiber core of the quartz optical fiber, and manually adjust the XY-direction alignment assembly.
Further, the two fiber alignment processes are: the method comprises the steps of welding a tail fiber (Corning SMF28 single-mode fiber) of a single-mode 1570nm laser with one end of a quartz fiber, aligning a power meter probe with one end of an aluminum fluoride-based glass fiber, and accurately adjusting the position of the fiber to enable the power meter to achieve the maximum reading.
Furthermore, the transition temperature Tg of the quartz optical fiber is 1175 ℃, and the transition temperature Tg of the aluminum fluoride-based glass optical fiber is 375 ℃.
Furthermore, the heating fire head is a V4 fire head made of graphite, and a uniform, stable, accurate and controllable thermal field is formed in the inverted omega-shaped heating ring, so that low-loss fusion of the optical fibers is realized.
Furthermore, the welding parameter is the distance l between the end faces of the two optical fibers 1 25 μm, pre-propulsion l 2 5 μm, thermal propulsion l 3 Is in the range of 15-19 μm, the advancing speed v is in the range of 50-80 μm/sec, the flame fusion offset d is in the range of 1550-1600 μm, the heating time t is in the range of 3-5s, and the fusion power P is in the range of 39-41W.
Further, the heating process of the fusion welding is that the quartz optical fiber is pushed into the aluminum fluoride-based glass optical fiber in a one-way mode, wherein the heat of the aluminum fluoride-based glass optical fiber reaching the softening temperature is indirectly conducted by the quartz optical fiber and air.
Furthermore, the cutting method is adopted for measuring the loss of the welding points.
The invention has the beneficial effects that:
(1) the invention has simple operation and strong repeatability, the welding success rate is 90 percent, the average loss of a welding point is 0.1dB, and the average tensile resistance is 200 g.
(2) The invention adopts the omega-shaped heating resistance wire to form a uniform, stable, accurate and controllable temperature field around the optical fiber to be welded, thereby being beneficial to reducing welding loss and improving the success rate of welding.
(3) The invention can be suitable for the fusion splicing between the quartz fiber and the special fiber made of other materials, and also can be suitable for the fusion splicing between the special fibers with different transition temperatures, and the fusion splicing point obtained by the fusion splicing has the advantages of low loss and high strength, thereby improving the stability and reliability of the fusion splicing point in practical application, realizing mass production and being beneficial to promoting the development of all-fiber lasers.
Drawings
FIG. 1: end view of an aluminum fluoride-based glass optical fiber for use in the present invention;
FIG. 2: end view of a silica optical fiber used in the present invention;
FIG. 3: schematic diagram of experimental device for the welding method of the present invention;
in the figure: 1-a computer, 2-a CCD camera, 3-an aluminum fluoride-based glass fiber, 4-a fiber clamping device, 5-a heating fire head and 6-a quartz fiber;
FIG. 4: two optical fiber fusion graphs obtained by the optical fiber fusion method are used;
in the figure, reference numeral a denotes an aluminum fluoride-based glass optical fiber, and b denotes a silica optical fiber.
Detailed Description
The following embodiments of the present invention are further illustrated with reference to the accompanying drawings, and the following embodiments are only used for explaining the present invention, but not for limiting the scope of the present invention.
The invention provides a fusion welding method of an aluminum fluoride-based glass optical fiber and a quartz optical fiber, which specifically comprises the following steps:
the method comprises the following steps: and preparing an optical fiber end face.
The end face treatment of the aluminum fluoride-based glass fiber and the quartz fiber comprises three links of stripping, cleaning and cutting. During cutting, a Vytran optical fiber cutting machine LDC401A is used for vertically cutting two ends of the aluminum fluoride-based glass optical fiber, the cutting pulling force is 220-230g, the end face diagram of the optical fiber is shown in figure 1, a single-mode cutting knife FC-6S is used for cutting the quartz optical fiber, and the end face diagram of the optical fiber is shown in figure 2.
Wherein the fiber core diameter of the aluminum fluoride-based glass fiber is 7-12 μm, the cladding diameter is 230-240 μm, the length is 1.2m, the quartz fiber is a corning SMF28 single-mode fiber, the fiber core diameter is 8.3 μm, and the cladding diameter is 125 μm.
Step two: the optical fiber is fixed and aligned.
The method comprises the steps of respectively fixing aluminum fluoride-based glass optical fibers and quartz optical fibers with smooth and flat end faces in optical fiber clamps at the left side and the right side of a Vytran large-fiber-core optical fiber fusion splicer GPX3400, then carrying out alignment operation on the fiber cores of the aluminum fluoride-based glass optical fibers and the fiber cores of the quartz optical fibers, and manually adjusting the XY-direction alignment assembly. The alignment process comprises the steps of welding a tail fiber (Corning SMF28 single-mode fiber) of a single-mode 1570nm laser with one end of a quartz fiber, aligning a probe of a power meter with one end of an aluminum fluoride-based glass fiber, observing the indication change of the power meter at any time, and accurately adjusting the position of the fiber to enable the indication of the power meter to be maximum.
Step three: and welding the aluminum fluoride-based glass fiber and the quartz fiber.
As the transition temperature (Tg-1175 ℃) of the quartz optical fiber is higher than the transition temperature (Tg-375 ℃) of the aluminum fluoride-based glass optical fiber, an asymmetric fusion mode is adopted, an experimental device diagram of the asymmetric fusion mode is shown in figure 3, the aluminum fluoride-based glass optical fiber 3 and the quartz optical fiber 6 are respectively placed in the optical fiber clamping devices 4 at the left side and the right side, the position of the heating fire head 5 is offset from the quartz optical fiber 6, the offset distance is d, and the heating temperature of the heating fire head is lower than the softening temperature of the quartz optical fiber 6 and higher than the softening temperature of the aluminum fluoride-based glass optical fiber 3. The optical fiber welding parameters are set in software pre-installed in the computer 1, and an optical fiber welding picture is observed through the CCD camera 2, so that low-loss and high-strength welding of the aluminum fluoride-based glass optical fiber 4 and the quartz optical fiber 6 is realized.
The Vytran large-core optical fiber fusion splicer heats by using an FTAV4 graphite heating wire assembly, and a uniform, stable, accurate and controllable thermal field is formed in the inverted omega-shaped heating ring, so that the low-loss fusion splicing of the optical fiber is realized. The set optical fiber welding parameters comprise the distance l between the end faces of the two optical fibers 1 25 μm, pre-propulsion l 2 5 μm, thermal propulsion l 3 Is in the range of 15-19 μm, the advancing speed v is in the range of 50-80 μm/sec, the flame fusion offset d is in the range of 1550-1600 μm, the heating time t is in the range of 3-5s, and the fusion power P is in the range of 39-41W.
The single-mode quartz optical fiber unidirectionally advances the aluminum fluoride-based glass optical fiber according to the advancing speed v in the fusion heating process, wherein the heat of the aluminum fluoride-based glass optical fiber reaching the softening temperature is indirectly conducted by the quartz optical fiber and air, and the indirect heating mode can provide a uniform and stable temperature field.
Step four: and measuring the loss and strength of the welding points.
And (3) determining the fusion loss of the fusion point by adopting a truncation method for the two fused optical fibers, and determining the strength of the fusion point by using tension monitoring in software. When the cutting method is adopted to determine the loss of the welding point, the cutting length of the aluminum fluoride-based glass optical fiber is more than 10cm each time, and the length of the rest part is more than 10cm, so that the accuracy of data is ensured.
The method is simple to operate and high in repeatability, and the operation process and the welding parameters are optimized, so that the welding loss can be effectively reduced, and the welding strength can be improved.
The fusion bonding diagram of the aluminum fluoride-based glass fiber and the quartz fiber obtained by the method is shown in fig. 4, the aluminum fluoride-based glass fiber is marked with a on the left, the single-mode quartz fiber is marked with b on the right, and the cladding diameter of the aluminum fluoride-based glass fiber is far larger than that of the single-mode quartz fiber, so that the aluminum fluoride-based glass fiber can firmly wrap the single-mode quartz fiber.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not intended to limit the present invention. Modifications and variations of this invention will occur to those skilled in the art and are intended to be included within the scope of this invention.

Claims (10)

1. A fusion welding method of aluminum fluoride-based glass fiber and quartz fiber is characterized in that:
firstly, end face treatment is carried out on an aluminum fluoride-based glass optical fiber and a quartz optical fiber, the aluminum fluoride-based glass optical fiber and the quartz optical fiber with smooth and flat end faces are respectively fixed in optical fiber clamps on the left side and the right side of a Vytran large-fiber-core optical fiber fusion splicer, then the aluminum fluoride-based glass optical fiber and the quartz optical fiber are aligned, the transition temperature of the quartz optical fiber is higher than that of the aluminum fluoride-based glass optical fiber, an asymmetric fusion splicing mode is adopted, the position of a used heating fire head is biased to the quartz optical fiber, the heating temperature of the used heating fire head is lower than the softening temperature of the quartz optical fiber and higher than that of the aluminum fluoride-based glass optical fiber, and then optical fiber fusion splicing parameters are set, low loss and high-strength fusion splicing of the aluminum fluoride-based glass optical fiber and the quartz optical fiber are realized, and fusion splice point loss and strength are finally measured.
2. The method according to claim 1, wherein the fusion-splicing of the aluminum fluoride-based glass optical fiber and the silica optical fiber is performed by: the fiber core diameter of the aluminum fluoride-based glass fiber is 7-12 μm, the cladding diameter is 230-240 μm, and the length is 1.2 m; the quartz fiber is a corning SMF28 single-mode fiber, the diameter of a fiber core of the fiber is 8.3 mu m, and the diameter of a cladding of the fiber is 125 mu m.
3. The method according to claim 1, wherein the fusion-splicing of the aluminum fluoride-based glass optical fiber and the silica optical fiber is performed by: the heating fire head is V4 fire head, the material of the heating fire head is graphite, and a uniform, stable, accurate and controllable thermal field is formed in the inverted heating ring, so that the low-loss fusion of the optical fiber is realized.
4. The method according to claim 1, wherein the fusion-splicing of the aluminum fluoride-based glass optical fiber and the silica optical fiber is performed by: the Vytran large-fiber-core optical fiber fusion splicer is GPX3400 and comprises a heating furnace assembly, an optical fiber clamping device, a CCD camera for imaging, a host machine and a display which are pre-installed with control software, and a reflector tower for side and end imaging.
5. The method for fusion-splicing an aluminum fluoride-based glass optical fiber and a quartz optical fiber according to claim 1, wherein: the lower fiber clamping inserts used in the left and right fiber clamps are respectively VHF250 and VHF160, the VHF250 is suitable for the fiber with the diameter of 177-320 mu m, and the VHF160 is suitable for the fiber with the diameter of 112-208 mu m.
6. The method according to claim 1, wherein the fusion-splicing of the aluminum fluoride-based glass optical fiber and the silica optical fiber is performed by: the alignment operation is to align the fiber core of the aluminum fluoride-based glass fiber and the fiber core of the quartz fiber and manually adjust the XY-direction alignment assembly.
7. The method according to claim 1, wherein the fusion-splicing of the aluminum fluoride-based glass optical fiber and the silica optical fiber is performed by: the alignment operation process comprises the following steps: and (3) welding a tail fiber of a single-mode 1570nm laser with one end of a quartz optical fiber, aligning a probe of the power meter with one end of an aluminum fluoride-based glass optical fiber, and accurately adjusting the position of the optical fiber to enable the power meter to achieve the maximum indicated number.
8. The method according to claim 1, wherein the fusion-splicing of the aluminum fluoride-based glass optical fiber and the silica optical fiber is performed by: the transition temperature Tg of the quartz optical fiber is 1175 ℃, and the transition temperature Tg of the aluminum fluoride-based glass optical fiber is 375 ℃.
9. The method for fusion-splicing an aluminum fluoride-based glass optical fiber and a quartz optical fiber according to claim 1, wherein: the welding parameter is the distance l between the end faces of the two optical fibers 1 25 μm, pre-propulsion l 2 5 μm, thermal propulsion l 3 Is in the range of 15-19 μm, the advancing speed v is in the range of 50-80 μm/sec, the flame fusion offset d is in the range of 1550-1600 μm, the heating time t is in the range of 3-5s, and the fusion power P is in the range of 39-41W.
10. The method according to claim 1, wherein the fusion-splicing of the aluminum fluoride-based glass optical fiber and the silica optical fiber is performed by: the heating process of the fusion welding is that the quartz optical fiber is unidirectionally pushed into the aluminum fluoride-based glass optical fiber, wherein the heat of the aluminum fluoride-based glass optical fiber reaching the softening temperature is indirectly conducted by the quartz optical fiber and air.
CN202210594218.9A 2022-05-27 2022-05-27 Welding method of aluminum fluoride-based glass fiber and quartz fiber Pending CN114859469A (en)

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CN202210594218.9A CN114859469A (en) 2022-05-27 2022-05-27 Welding method of aluminum fluoride-based glass fiber and quartz fiber

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