CN118276237A - Infrared glass fiber side pumping beam combiner preparation facilities - Google Patents

Abstract

The invention discloses a preparation device of an infrared glass optical fiber side-pumped beam combiner, which comprises a fixing unit, an optical fiber positioning unit and a heating unit, wherein the fixing unit comprises a pedestal, a first fixing block, a second fixing block and a third fixing block are sequentially and slidably arranged on the front surface of the pedestal from top to bottom, the optical fiber positioning unit comprises a glass tube and a plurality of beam-forming fibers, the glass tube comprises a cylindrical tube and a conical tube which are connected up and down, the cylindrical tube is fixed on the first fixing block, the upper ends of the beam-forming fibers are fixed in the first fixing block, the lower ends of the beam-forming fibers penetrate into the conical tube and the lower end surfaces of the beam-forming fibers are level with the lower end surfaces of the conical tube, each beam-forming fiber is an optical fiber with refractive index lower than that of the infrared glass optical fiber and melting point higher than that of the infrared glass optical fiber, the heating unit comprises a heating tube and a temperature control unit with upper opening and lower opening, and the heating tube is fixed on the second fixing block and sleeved on the outer side of the conical tube. The device has the advantages of stable structure, uniform heat energy distribution, simple and convenient operation and accurate control, and can efficiently and reliably prepare the infrared glass optical fiber side-pumped beam combiner.

Description

Infrared glass fiber side pumping beam combiner preparation facilities

Technical Field

The invention belongs to the technical field of infrared glass optical fibers, and particularly relates to a preparation device of an infrared glass optical fiber side-pumped beam combiner.

Background

The mid-infrared fiber laser has wide application prospect in the important fields of aerospace, military, biomedical, environmental monitoring, material processing, national defense and the like due to the special working wavelength and excellent atmospheric penetration capability. However, doped silica fibers are challenging in achieving laser output in the wavelength band above 2.2 μm due to the multi-phonon relaxation effect caused by the high phonon energy of the silica glass material. In recent years, special multicomponent infrared glass optical fibers with non-quartz matrixes, represented by fluoride glass optical fibers, fluorotellurate glass optical fibers and chalcogenide glass optical fibers, have become ideal gain media of mid-infrared optical fiber lasers due to the unique advantages of low phonon energy of the fiber matrix glass, high solubility of rare earth ions, high infrared transition efficiency in the rare earth ions and the like. With the continuous progress of infrared glass fiber manufacturing process and device manufacturing technology, high power and full fibrillation have become a significant trend in mid-infrared fiber laser development.

The optical fiber side pumping beam combiner is an all-fiber device, and pump light energy is coupled into a single signal optical fiber through one or more tapered pump optical fibers by the side surface, so that the problems of limited laser input and output power and thermal damage of the device are effectively solved. However, compared with quartz fibers, infrared glass fibers have extremely low mechanical strength and melting point, making conventional torsion knotting methods and heat shrink tube heating tapering methods difficult to be applied to the preparation of non-quartz-matrix infrared glass fiber side-pumped beam combiners.

At present, the preparation of the infrared glass fiber pump beam combiner mainly depends on a tapering fusion method. For example, the utility model patent "a mid-infrared fiber laser pump beam combiner device with high gain factor" (application number 202021354453.1) realizes the welding with the fluoride fiber by reducing the welding time of oxyhydrogen flame in the tapering process, but the control of oxyhydrogen flame temperature is easily affected by the gas flow, and increases the risk of crystallization of the fluoride fiber. The utility model relates to a middle infrared optical fiber pumping beam combiner and a preparation method thereof (application number 202110227296.0), which realize the end pumping beam combiner by adopting a mode of drawing a preform rod by sectional temperature control, but have the problem that the size and the mode field caused by simultaneous tapering of a plurality of beam combining optical fibers are difficult to accurately control. The utility model discloses an end-pumped mid-infrared optical fiber combiner and a manufacturing method thereof (application number 202211182471. X), wherein the end-pumped combiner is realized by using a curing material to glue a tapered quartz optical fiber and the end face of an infrared glass optical fiber, so that the tapered of a signal optical fiber is avoided, but the curing material can obstruct the side face of the optical fiber and absorb the escaped pumping light energy, and the risk of damage of a device is increased. In addition, traditional pumping beam combiner preparation facilities heats the optic fibre of placing in order to realize the side fusion to the horizontal direction, in the in-process of heating optic fibre, because of the effect of optic fibre gravity, can lead to the uneven and laminating dislocation of pumping optic fibre.

The side welding process comprises the key technical difficulties of optical fiber tapering, optical fiber side fitting, side heating fusion and the like, and the characteristics of low mechanical strength, easiness in breakage, easiness in oxidation during heating and the like of the infrared glass optical fiber, and the lack of a preparation device suitable for the infrared glass optical fiber side pumping beam combiner in the prior art severely limits the potential of the infrared glass optical fiber side pumping beam combiner in mid-infrared optical fiber laser application.

Disclosure of Invention

The invention aims to solve the technical problem of providing the preparation device of the infrared glass optical fiber side-pumped beam combiner, which has the advantages of stable structure, uniform heat energy distribution, simple operation and accurate control, aiming at the defects of the prior art.

The technical scheme adopted for solving the technical problems is as follows: the preparation device comprises a fixing unit, an optical fiber positioning unit and a heating unit, wherein the fixing unit comprises a pedestal, a first fixing block, a second fixing block and a third fixing block are sequentially and slidably arranged on the front surface of the pedestal from top to bottom, the optical fiber positioning unit comprises a glass tube and a plurality of beam forming fibers, the upper end and the lower end of the glass tube are respectively opened, the glass tube is used for realizing the regular arrangement of a plurality of beam-forming fibers, signal fibers and a plurality of pumping fibers, the glass tube comprises a cylindrical tube and a conical tube which are connected up and down, the upper opening of the conical tube is large, the lower opening of the conical tube is small, the cylindrical tube is fixed on the first fixed block, the upper ends of the beam-forming fibers are fixed on the first fixed block, the lower ends of the beam-forming fibers penetrate into the conical tube, the lower end face of each beam-forming fiber is level with the lower end face of the conical tube, each beam-forming fiber is an optical fiber with refractive index lower than that of the infrared glass fiber and melting point higher than that of the infrared glass fiber, and the heating unit comprises a heating tube with upper opening and lower opening and a temperature control unit, and the heating tube is fixed on the second fixed block and sleeved on the outer side of the conical tube;

When the side pump beam combiner is prepared, the upper ends of the signal optical fiber and the plurality of pump optical fibers are fixed on a first fixed block, the lower ends of the signal optical fiber and the plurality of pump optical fibers penetrate through a conical tube to be fixed on a third fixed block, the positions of the first fixed block and the third fixed block are finely adjusted to enable the signal optical fiber and the plurality of pump optical fibers to be in a vertical state, the upper end faces of waist regions of the plurality of pump optical fibers are flush with the lower end faces of the conical tube, then an appropriate amount of alcohol solvent is dripped into the conical tube, the upper end of the waist region of each pump optical fiber is respectively tangent with the side faces of the signal optical fiber and the two groups of beam optical fibers, the lower end of each group of optical fibers is respectively tangent with the side faces of the inner walls of the signal optical fiber and the conical tube, the side faces of the adjacent two groups of beam optical fibers are tangent, then the temperature of a heating tube is controlled within a softening temperature range of _s +/-10 ℃ through a temperature control unit, fusion between the side faces of the waist regions of the plurality of pump optical fibers and the signal optical fibers is achieved, finally, the refractive index of the glass optical fibers is lower than that the glass fiber is matched with the side faces of the glass tube, and the glass fiber is sealed, and the glass fiber is obtained.

Compared with the traditional preparation device of the pump beam combiner placed in the horizontal direction of the optical fiber, the preparation device can realize the side fusion of the pump optical fiber and the signal optical fiber in a vertical state, and can effectively prevent the problems of uneven distribution and lamination dislocation of the pump optical fiber caused by the gravity of the optical fiber in the process of heating the optical fiber.

The preparation device realizes the regular arrangement of a plurality of beam fibers, signal fibers and a plurality of pumping fibers through the glass tube. When the optical fiber is assembled, the pumping optical fibers and the signal optical fibers are tightly sleeved into the glass tube which is provided with the assembled optical fibers in advance, so that the accurate arrangement and the efficient coupling among the optical fibers are realized, meanwhile, the assembly mode effectively limits the arrangement space of the pumping optical fibers, and ensures the stability of the attaching mode of the pumping optical fibers. In addition, through the arrangement layout of different optical fibers, the cone region of the pumping optical fiber is prevented from being broken due to insufficient mechanical strength, and the sealing fixation between the optical fiber and the conical tube is realized by tangential connection of the beam combining optical fiber and the inner wall side surface of the conical tube, so that the mechanical stability of the overall structure of the pumping beam combiner is remarkably improved. The preparation device realizes the beam combination of the optical fibers through the glass tube, ensures the uniform distribution of the pumping optical fibers, and finally prepares the side-pumping beam combiner with the length of (N+1) multiplied by 1, wherein N is the number of the pumping optical fibers. The preparation device disclosed by the invention can adapt to the thermal expansion of the infrared glass optical fibers and prevent the optical fibers from separating or misplacing through the matching of the glass tubes and the plurality of beam combining fibers, so that the problem of side fusion of the pump optical fibers and the signal optical fibers is effectively solved, the prepared pump beam combiner is ensured to realize efficient optical coupling at the minimum diameter of the pump optical fibers, and sufficient mechanical strength and thermal stability are maintained.

Particularly, the invention adopts the beam combining fiber with the refractive index lower than that of the infrared glass fiber, and the beam combining fiber not only provides physical protection for the infrared glass fiber, but also serves as an optical limiting layer, thereby effectively reducing light leakage and crosstalk and further improving the quality of pumping light transmission and the reliability of a system.

The preparation device heats the conical tube through the heating tube, so that the pump optical fiber and the signal optical fiber which are positioned in the conical tube are heated, and the side fusion of the pump optical fiber and the signal optical fiber is realized. The combined structure of the heating pipe and the conical pipe can effectively isolate impurities in the outside air, and avoids the scrapping risk of the pump beam combiner caused by heat absorption of the impurities. In addition, the prepared pump beam combiner is directly packaged and fixed in the glass tube, and the packaging and fixing mode is beneficial to protecting the optical fiber, so that the optical fiber is prevented from being interfered by the external environment, and the optical performance of the pump beam combiner is enhanced.

Preferably, the front surface of the pedestal is fixed with two vertically arranged slide rails, the first fixing block, the second fixing block and the third fixing block are sequentially installed on the two slide rails through sliding blocks from top to bottom, a plurality of through holes for penetrating the signal optical fibers, the plurality of pumping optical fibers and the plurality of beam-forming fibers are vertically formed in the first fixing block, a U groove and a first pressing block are formed in the front surface of the first fixing block and are magnetically adsorbed on the first fixing block, the U groove is used for placing the cylindrical tube, the first pressing block is used for pressing the cylindrical tube, a plurality of V grooves and magnetic adsorption on the front surface of the third fixing block are formed in the second pressing block, the plurality of V grooves are used for placing the signal optical fibers and the plurality of pumping optical fibers, and the second pressing block is used for pressing the signal optical fibers and the plurality of pumping optical fibers.

Preferably, the signal optical fiber, the plurality of pump optical fibers and the plurality of beam-forming optical fibers are all optical fibers with coating layers, the outer diameter of the coating layer of each optical fiber is larger than the aperture of each through hole, the outer diameter of the bare fiber of each optical fiber after the coating layer is removed is smaller than the aperture of each through hole, and the bare fiber of each optical fiber penetrates through each through hole from top to bottom. Because the external diameter of the coating layer of each optical fiber is greater than the aperture of each through hole, the external diameter of the bare fiber of each optical fiber after the coating layer is removed is less than the aperture of each through hole, thereby the upper end of each optical fiber can be conveniently fixed on the first fixed block through the cooperation of the coating layer and the through hole, the structure is simple, and the operation is convenient.

Preferably, the front surface of the pedestal is provided with a semicircular groove, the semicircular groove is arranged between the two sliding rails, the number of the second fixing blocks is two, each sliding rail is provided with one second fixing block through a sliding block, the heating pipe is embedded into the semicircular groove, and two side walls of the heating pipe are respectively fixed on the two second fixing blocks through long screws.

Preferably, a plurality of heating rods are uniformly distributed on the inner wall of the heating pipe, and the heating rods are connected with the temperature control unit through cables. The evenly distributed heating bars inside the heating tube help to create a stable and uniform temperature field.

Preferably, each heating rod is made of stainless steel, and the heating pipe is made of stainless steel or pure copper.

Preferably, a water cooling circulation channel is arranged in the pedestal, a water inlet and a water outlet which are communicated with an external water supply mechanism are arranged on the pedestal, and a plurality of heat dissipation holes are arranged on the pedestal. The combined design of the water cooling circulation channel and the plurality of heat dissipation holes can improve the heat dissipation efficiency of the pedestal in the operation process of the device, so that the effective cooling of parts mounted on the pedestal is realized, the moving precision of the first fixed block, the second fixed block, the third fixed block and the like is ensured, the stability and the reliability of the device under the long-time or high-load working condition are improved, the damage risk of the device caused by overheating is reduced, and the preparation precision and the preparation efficiency of the pump beam combiner are ensured.

Preferably, the front surface of the pedestal is fixed with an upper limit baffle and a lower limit baffle, the upper limit baffle is arranged on the upper side of the first fixed block, the upper limit baffle is used for limiting the upward movement stroke of the first fixed block, the lower limit baffle is arranged on the lower side of the third fixed block, and the lower limit baffle is used for limiting the downward movement stroke of the third fixed block. The design of the upper limit baffle and the lower limit baffle is beneficial to limiting the moving range of the upper limit baffle and the lower limit baffle, and ensures the safety and the accuracy of operation.

Preferably, the refractive index difference between each of the group beam fibers and the infrared glass fiber satisfies the following conditions:

Wherein n ₁ is the refractive index of the infrared glass fiber, and n ₂ is the refractive index of the group fiber.

Preferably, each of the beam-forming fibers is a quartz fiber, the infrared glass fiber is a fluoride glass fiber, a fluorotellurite glass fiber or a chalcogenide glass fiber, and the glass tube is a quartz glass tube.

Compared with the prior art, the invention has the following advantages: the preparation device of the side pump beam combiner of the infrared glass fiber has the characteristics of stable structure, uniform heat energy distribution, simple operation, accurate control and the like, utilizes the low-melting-point characteristic of the infrared glass fiber, combines the restraint effect of the high-melting-point beam combining fiber and the glass tube, accurately controls the heating process, can realize the accurate side fusion of the taper region of the pump fiber in a vertical state and the signal fiber, and can effectively prevent the uneven distribution and the lamination dislocation problem of the pump fiber caused by the gravity of the fiber in the process of heating the fiber, thereby efficiently and reliably preparing the side pump beam combiner of the infrared glass fiber.

Drawings

FIG. 1 is a schematic view of the device for preparing an infrared glass fiber side-pumped combiner according to an embodiment;

FIG. 2 is a schematic diagram showing the relative positions of the heating tube, the second fixing block and the glass tube after the heating tube is fixed in the embodiment;

FIG. 3 is a schematic diagram showing the effect of the lower ends of bare fibers of the signal fiber and the pump fiber penetrating into a through hole from top to bottom in the process of preparing the side pump combiner of (1+1). Times.1;

FIG. 4 is a schematic view showing the effect of the bare fiber lower ends of the signal fiber and the pump fiber passing through the glass tube in the process of preparing the (1+1). Times.1 side-pumped combiner;

FIG. 5 is a schematic diagram of the pump fiber according to an embodiment;

FIG. 6 is a fiber bundle diagram of a (1+1). Times.1 side pump combiner;

FIG. 7 is a fiber pack diagram of a (6+1). Times.1 side pump combiner;

Specific reference numerals in the drawings are as follows:

11-pedestal, 12-water inlet, 13-water outlet, 14-heat dissipation hole, 15-upper limit baffle, 16-lower limit baffle, 17-slide rail, 21-glass tube, 22-group beam fiber, 23-cylinder tube, 24-conical tube, 31-heating tube, 32-temperature control unit, 32-heating rod, 34-cable, 35-long screw, 41-first fixed block, 42-second fixed block, 43-third fixed block, 44-through hole, 45-U groove, 46-first briquetting, 47-second briquetting, 51-pumping optical fiber, 52-signal optical fiber, 53-waist region, 54-cone region.

Detailed Description

The invention is described in further detail below with reference to the embodiments of the drawings.

The preparation device of the infrared glass fiber side-pumped beam combiner in the embodiment comprises a signal fiber 52 and a plurality of pumping fibers 51, wherein the pumping fibers 51 are tapered fibers, the tapered fibers comprise a waist region 53 (namely a part between an upper horizontal dashed line and a lower horizontal dashed line in fig. 5) and tapered regions 54 symmetrically connected with two sides of the waist region 53, the signal fiber 52 and the pumping fibers 51 are infrared glass fibers with non-quartz matrixes, the preparation device comprises a fixing unit, a fiber positioning unit and a heating unit, the fixing unit comprises a pedestal 11, a water cooling circulation channel is arranged in the pedestal 11, a water inlet 12 and a water outlet 13 which are communicated with an external water supply mechanism are arranged on the pedestal 11, a plurality of heat dissipation holes 14 are arranged on the pedestal 11, a first fixing block 41, a second fixing block 42 and a third fixing block 43 are sequentially arranged on the front surface of the pedestal 11 in a sliding manner from top to bottom, an upper limit baffle 15 and a lower limit baffle 16 are fixed, the upper limit baffle 15 is arranged on the upper side of the first fixed block 41, the upper limit baffle 15 is used for limiting the upward movement of the first fixed block 41, the lower limit baffle 16 is arranged on the lower side of the third fixed block 43, the lower limit baffle 16 is used for limiting the downward movement of the third fixed block 43, the optical fiber positioning unit comprises a glass tube 21 and a plurality of beam-forming fibers 22, the upper ends and the lower ends of which are respectively opened, the glass tube 21 is used for realizing the regular arrangement of the plurality of beam-forming fibers 22, the signal optical fibers 52 and a plurality of pumping optical fibers 51, the glass tube 21 comprises a cylindrical tube 23 and a conical tube 24 which are connected up and down, the upper opening and the lower opening of the conical tube 24 are small, the cylindrical tube 23 is fixed on the first fixed block 41, the upper ends of the plurality of beam-forming fibers 22 are fixed on the first fixed block 41, the lower ends of the plurality of beam-forming fibers 22 penetrate into the conical tube 24, the lower end face of each group of bundle fibers 22 is flush with the lower end face of the conical tube 24, each group of bundle fibers 22 is an optical fiber with refractive index lower than that of the infrared glass optical fiber and melting point higher than that of the infrared glass optical fiber, the heating unit comprises a heating pipe 31 with upper and lower openings and a temperature control unit 32, the heating pipe 31 is fixed on a second fixing block 42 and sleeved on the outer side of the conical tube 24, a plurality of heating rods 33 are uniformly distributed on the inner wall of the heating pipe 31, the heating rods 33 are connected with the temperature control unit 32 through cables 34, each heating rod 33 can be made of stainless steel, and the heating pipe 31 can be made of stainless steel or pure copper.

In this embodiment, two vertically arranged slide rails 17 are fixed on the front surface of the pedestal 11, the first fixing block 41, the second fixing block 42 and the third fixing block 43 are sequentially installed on the two slide rails 17 from top to bottom through sliding blocks (not shown in the figure), a plurality of through holes 44 for penetrating the signal optical fibers 52, a plurality of pump optical fibers 51 and a plurality of beam-forming fibers 22 are vertically formed in the first fixing block 41, a U-shaped groove 45 is formed in the front surface of the first fixing block 41 and is magnetically adsorbed with a first pressing block 46, the U-shaped groove 45 is used for placing a cylindrical tube 23, the first pressing block 46 is used for pressing the cylindrical tube 23, a plurality of V-shaped grooves (not shown in the figure) are formed in the front surface of the third fixing block 43 and are magnetically adsorbed with a second pressing block 47, the plurality of V-shaped grooves are used for placing the signal optical fibers 52 and the plurality of pump optical fibers 51, and the second pressing block 47 are used for pressing the signal optical fibers 52 and the plurality of pump optical fibers 51.

In this embodiment, the signal optical fiber 52, the plurality of pump optical fibers 51 and the plurality of bundle optical fibers 22 are all optical fibers with coating layers, the outer diameter of the coating layer of each optical fiber is larger than the aperture of each through hole 44, the outer diameter of the bare fiber of each optical fiber after removing the coating layer is smaller than the aperture of each through hole 44, and the bare fiber of each optical fiber penetrates through each through hole 44 from top to bottom. As shown in fig. 5, the upper end of the pump fiber 51 in fig. 5 is a coated portion with a larger outer diameter, the fiber section below the coated portion is a bare fiber, the middle of the bare fiber is a waist region 53 of the pump fiber 51, and the upper and lower sides of the waist region are tapered regions 54, respectively.

In this embodiment, the front surface of the base 11 is provided with the semicircular groove 18, the semicircular groove 18 is disposed between the two sliding rails 17, the number of the second fixing blocks 42 is two, each sliding rail 17 is provided with one second fixing block 42 through a sliding block, the heating pipe 31 is embedded into the semicircular groove 18, and two side walls of the heating pipe 31 are respectively fixed on the two second fixing blocks 42 through the long screw rods 35.

In this embodiment, the refractive index difference between each group of beam fibers 22 and the infrared glass fiber satisfies the following conditions:

Wherein n ₁ is the refractive index of the infrared glass fiber, and n ₂ is the refractive index of the group fiber. Specifically, each of the group fibers 22 is a silica fiber, the infrared glass fiber is a fluoride glass fiber, a fluorotellurate glass fiber, or a chalcogenide glass fiber, and the glass tube 21 is a silica glass tube 21.

When the side pump beam combiner is prepared, the upper ends of the signal optical fiber 52 and the plurality of pump optical fibers 51 are fixed on the first fixed block 41, the lower ends of the signal optical fiber 52 and the plurality of pump optical fibers 51 penetrate through the conical tube 24 and are fixed on the third fixed block 43, the positions of the first fixed block 41 and the third fixed block 43 are finely adjusted, the signal optical fiber 52 and the plurality of pump optical fibers 51 are in a vertical state, the upper end face of the waist area 53 of the plurality of pump optical fibers 51 is level with the lower end face of the conical tube 24, then a proper amount of alcohol solvent is dripped into the conical tube 24, the upper end of the waist area 53 of each pump optical fiber 51 is tangent with the side faces of the signal optical fiber 52 and the two beam combining optical fibers 22 respectively, the lower end of each beam combining optical fiber 22 is tangent with the side faces of the inner walls of the signal optical fiber 52 and the conical tube 24 respectively, and the side surfaces of two adjacent beam-forming fibers 22 are tangent, then the temperature of a heating pipe 31 is controlled within the range of softening temperature T _s +/-10 ℃ of the infrared glass fibers through a temperature control unit 32, and heat is preserved for 30-60 seconds, so that the fusion of the conical region 54 above the waist region 53 of a plurality of pumping fibers 51 with the side surface of the signal fiber 52 is realized, finally, the refractive index matching liquid with the refractive index lower than that of the infrared glass fibers is injected into the glass tube 21, after the refractive index matching liquid is solidified, the signal fiber 52, the plurality of pumping fibers 51 and the plurality of beam-forming fibers 22 are cut off from the upper side of the glass tube 21, and the plurality of pumping fibers 51 are cut off from the lower end surface of the glass tube 21, namely, the side pumping beam combiner is obtained through encapsulation.

The above-described preparation apparatus can be used to prepare a (n+1) ×1 side-pumped combiner, where N is the number of pump fibers 51. Taking a side-pumped beam combiner of (1+1) ×1 as an example, the side-pumped beam combiner is composed of a signal optical fiber 52 and a pump optical fiber 51, the external view of the pump optical fiber 51 is shown in fig. 5, and the waist area 53 is 18-19.5 μm in diameter. The specific operation steps of the side pump beam combiner for preparing the (1+1) x 1 by using the preparation device are as follows:

1) Connecting the water inlet 12 and the water outlet 13 on the pedestal 11 with an external water supply mechanism, starting water cooling circulation, and moving the first fixed block 41 upwards to the upper limit baffle 15;

2) Removing the coating layers except the upper ends of the two group beam fibers 22, the signal optical fiber 52 and the pump optical fiber 51 with the coating layers, exposing bare fibers below the upper ends of the optical fibers, penetrating the lower ends of the bare fibers of the signal optical fiber 52 and the pump optical fiber 51 into a through hole 44 (shown in fig. 3) from top to bottom respectively, penetrating a glass tube 21 (shown in fig. 4) which is fixed on a first fixing block 41 in advance, placing the lower ends of the bare fibers of the signal optical fiber 52 and the pump optical fiber 51 in a V-shaped groove on a third fixing block 43, and compacting the lower ends of the signal optical fiber 52 and the pump optical fiber 51 through a second pressing block 47, namely finishing the fixing of the upper ends of the group beam fibers 22, the signal optical fiber 52 and the pump optical fiber 51 on the first fixing block 41 and the fixing of the lower ends of the signal optical fiber 52 and the pump optical fiber 51 on the first fixing block 41 and the third fixing block 43;

3) The positions of the first fixing block 41 and the third fixing block 43 are finely adjusted, so that the signal optical fiber 52 and the pump optical fiber 51 are in a vertical state, the upper end face of a waist region 53 of the pump optical fiber 51 is flush with the lower end face of the conical tube 24, then a proper amount of alcohol solvent is dripped into the conical tube 24, the upper end of the waist region 53 of the pump optical fiber 51 is respectively tangent to the side faces of the signal optical fiber 52 and the two beam-forming fibers 22, the lower end of each beam-forming fiber 22 is respectively tangent to the side faces of the inner walls of the signal optical fiber 52 and the conical tube 24, the side faces of the adjacent two beam-forming fibers 22 are tangent, the optical fiber beam-forming diagram of the side pump beam combiner (1+1) x 1 is shown in fig. 6, and the caliber of the lower opening of the conical tube 24 (i.e. the minimum inner diameter of the conical tube 24) is matched with the outer diameter of an optical fiber beam after optical fiber beam forming; and then adjusting the position of the second fixing block 42 to enable the heating pipe 31 to be sleeved outside the conical pipe 24 (as shown in fig. 2), then controlling the temperature of the heating pipe 31 within the range of softening temperature T _s +/-10 ℃ of the infrared glass optical fibers through the temperature control unit 32, and preserving heat for 30-60 seconds, namely realizing fusion between the conical area 54 above the waist area 53 of the plurality of pumping optical fibers 51 and the side face of the signal optical fiber 52, finally injecting an index matching liquid with the refractive index lower than that of the infrared glass optical fibers into the glass pipe 21, cutting off the signal optical fibers 52, the pumping optical fibers 51 and the two group beam optical fibers 22 from the upper surface of the first fixing block 41 after the index matching liquid is irradiated and solidified by an ultraviolet lamp, and cutting off the pumping optical fibers 51 from the lower end face of the glass pipe 21, namely packaging to obtain the side pumping beam combiner of the side pumping beam combiner with the (1+1). Times.1.

In practical application, different side-pumped beam combiners can be prepared through the arrangement and layout of different optical fibers. FIG. 7 is a fiber bundle diagram of a (6+1). Times.1 side-pumped combiner.

The preparation device realizes the regular arrangement of a plurality of beam-forming fibers 22, signal fibers 52 and a plurality of pumping fibers 51 through the glass tube 21. During beam assembly, the pump optical fibers 51 and the signal optical fibers 52 are tightly sleeved into the glass tube 21 provided with the beam assembly optical fibers 22 in advance, so that precise arrangement and efficient coupling among the optical fibers are realized, meanwhile, the beam assembly mode effectively limits the arrangement space of the pump optical fibers 51, and ensures the stability of the attaching mode of the pump optical fibers 51. In addition, through the arrangement layout of different optical fibers, the cone region 54 of the pump optical fiber 51 is prevented from being broken due to insufficient mechanical strength, and the sealing fixation between the optical fibers and the conical tube 24 is realized by tangent the beam combining fiber 22 and the inner wall side surface of the conical tube 24, so that the mechanical stability of the overall structure of the pump beam combiner is remarkably improved.

Claims (10)

1. The utility model provides an infrared glass optic fibre side pumping beam combiner preparation facilities, side pumping beam combiner constitute by a signal optical fiber and a plurality of pumping optic fibre, a plurality of pumping optic fibre be the tapering optic fibre, the tapering optic fibre include waist district and symmetrical connection setting in the cone district of waist district both sides, signal optical fiber and a plurality of pumping optic fibre be the infrared glass optic fibre of non-quartz matrix, its characterized in that: the preparation device comprises a fixing unit, an optical fiber positioning unit and a heating unit, wherein the fixing unit comprises a pedestal, a first fixing block, a second fixing block and a third fixing block are sequentially and slidably arranged on the front surface of the pedestal from top to bottom, the optical fiber positioning unit comprises a glass tube and a plurality of group beam fibers, the upper end and the lower end of the glass tube are respectively provided with openings, the glass tube is used for realizing the regular arrangement of the plurality of group beam fibers, signal optical fibers and a plurality of pumping optical fibers, the glass tube comprises a cylindrical tube and a conical tube which are connected up and down, the upper opening and the lower opening of the conical tube are small, the cylindrical tube is fixed on the first fixing block, the upper ends of the plurality of group beam fibers are fixed on the first fixing block, the lower ends of the plurality of group beam fibers penetrate into the conical tube, the lower end face of each group beam fiber is flush with the lower end face of the conical tube, the group beam fibers are refractive index lower than that of infrared glass and higher than that of the infrared glass tube and the infrared tube is fixed on the outer side of the heating tube, and the heating tube is fixed on the outer side of the infrared tube;

When the side pump beam combiner is prepared, the upper ends of the signal optical fiber and the plurality of pump optical fibers are fixed on a first fixed block, the lower ends of the signal optical fiber and the plurality of pump optical fibers penetrate through a conical tube to be fixed on a third fixed block, the positions of the first fixed block and the third fixed block are finely adjusted to enable the signal optical fiber and the plurality of pump optical fibers to be in a vertical state, the upper end faces of waist regions of the plurality of pump optical fibers are flush with the lower end faces of the conical tube, then an appropriate amount of alcohol solvent is dripped into the conical tube, the upper end of the waist region of each pump optical fiber is respectively tangent with the side faces of the signal optical fiber and the two groups of beam optical fibers, the lower end of each group of optical fibers is respectively tangent with the side faces of the inner walls of the signal optical fiber and the conical tube, the side faces of the adjacent two groups of beam optical fibers are tangent, then the temperature of a heating tube is controlled within a softening temperature range of _s +/-10 ℃ through a temperature control unit, fusion between the side faces of the waist regions of the plurality of pump optical fibers and the signal optical fibers is achieved, finally, the refractive index of the glass optical fibers is lower than that the glass fiber is matched with the side faces of the glass tube, and the glass fiber is sealed, and the glass fiber is obtained.

2. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 1, wherein: the front of pedestal be fixed with the slide rail of the vertical setting of twice, first fixed block, second fixed block and third fixed block pass through the slider from top to bottom in proper order respectively on the slide rail on twice, first fixed block on vertically seted up be used for penetrating signal fiber, a plurality of pumping optic fibre and a plurality of group beam fiber's a plurality of through-holes, the front of first fixed block seted up U groove and magnetic force and adsorbed first briquetting, the U groove be used for placing the cylinder pipe, first briquetting be used for compressing tightly the cylinder pipe, the front of third fixed block set up a plurality of V grooves and magnetic force and adsorbed second briquetting, a plurality of V grooves be used for placing signal fiber and a plurality of pumping optic fibre, the second briquetting be used for compressing tightly signal fiber and a plurality of pumping optic fibre.

3. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 2, wherein: the signal optical fibers, the plurality of pump optical fibers and the plurality of beam-forming optical fibers are optical fibers with coating layers, the outer diameter of each coating layer of each optical fiber is larger than the aperture of each through hole, the outer diameter of each bare fiber of each optical fiber after the coating layers are removed is smaller than the aperture of each through hole, and the bare fiber of each optical fiber penetrates through each through hole from top to bottom.

4. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 2, wherein: the front of pedestal set up the semicircle groove, the semicircle groove locate twice between the slide rail, the quantity of second fixed block be two, every the slide rail on install one through the slider the second fixed block, the heating pipe embedding semicircle groove, the both sides wall of heating pipe be fixed in two respectively through long screw rod the second fixed block.

5. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 4, wherein: the inner wall of the heating pipe is uniformly provided with a plurality of heating rods, and the heating rods are connected with the temperature control unit through cables.

6. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 5, wherein: each heating rod is made of stainless steel, and the heating pipe is made of stainless steel or pure copper.

7. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 2, wherein: the water cooling device is characterized in that a water cooling circulation channel is arranged in the pedestal, a water inlet and a water outlet which are communicated with an external water supply mechanism are arranged on the pedestal, and a plurality of heat dissipation holes are formed in the pedestal.

8. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 1, wherein: the front of pedestal be fixed with limit baffle and lower limit baffle, last limit baffle locate the upside of first fixed block, last limit baffle be used for limiting the upward movement stroke of first fixed block, lower limit baffle locate the downside of third fixed block, lower limit baffle be used for limiting the downward movement stroke of third fixed block.

9. The infrared glass fiber side-pumped combiner manufacturing apparatus of claim 1, wherein: the refractive index difference between each beam fiber and the infrared glass fiber is as follows:

Wherein n ₁ is the refractive index of the infrared glass fiber, and n ₂ is the refractive index of the group fiber.

10. The infrared glass fiber side-pumped combiner fabrication apparatus of claim 9, wherein: each beam fiber is a quartz optical fiber, the infrared glass optical fiber is a fluoride glass optical fiber, a fluorotellurite glass optical fiber or a chalcogenide glass optical fiber, and the glass tube is a quartz glass tube.