A polarization-maintaining dual-fiber pigtail and its automatic alignment device and method

Abstract

This invention discloses a polarization-maintaining dual-fiber pigtail and its automatic alignment device and method, belonging to the technical field of polarization-maintaining fiber. It includes a rotating clamping assembly, a curing assembly, and an imaging recognition assembly correspondingly arranged on a worktable. By utilizing the corresponding arrangement of the capillary fixing block and the support block, reliable fixation of the fiber-threaded capillary can be achieved. Furthermore, the coordinated work of the rotating clamping assembly and the imaging recognition assembly enables rapid identification of the end-face state of the two polarization-maintaining fibers in the capillary during alignment and rapid adjustment of the fiber position. The automatic alignment device of this invention has a simple structure, is easy to assemble, disassemble, and operate, and can accurately identify the end-faces of the two polarization-maintaining fibers during alignment in the capillary, and automatically adjust the fiber alignment angle, improving the alignment accuracy of the polarization-maintaining fiber, the fabrication accuracy of the polarization-maintaining dual-fiber pigtail, and the product's yield and performance, thus possessing significant practical value.

Description

Technical Field

[0001] This invention belongs to the field of polarization-maintaining optical fiber technology, specifically relating to an automatic alignment device for polarization-maintaining dual-fiber pigtails and an automatic alignment method using the device, as well as a polarization-maintaining dual-fiber pigtail produced by the automatic alignment method. Background Technology

[0002] Generally, polarization-maintaining fiber consists of a core and two stress zones, which can maintain the transmission of linearly polarized positive light. In the application of polarization-maintaining fiber, the process of axial connection of polarization-maintaining fiber is often encountered, and in the process of splicing polarization-maintaining fiber, it is usually necessary to align the angles of its stress zones.

[0003] Currently, axis-aligned connections of polarization-maintaining fibers (PSM) are typically achieved using conventional PSM connectors or fusion splicing. When using conventional PSM connectors, ferrule adhesive is usually required for connection; however, the stress from the adhesive often results in low alignment accuracy (typically ±3°), leading to an extinction ratio of only around 25 dB, which is insufficient for high-precision applications. Therefore, fusion splicing is typically used for high-performance PSM connections. Fusion splicing achieves alignment accuracy of ±1° and an extinction ratio exceeding 35 dB, effectively meeting the demands of high-precision applications. However, compared to conventional PSM connectors, PSM fusion splicing also presents challenges in field maintenance, lower mechanical performance, and inability to support new multi-core devices, resulting in significant application limitations.

[0004] In addition, with the development of polarization-maintaining fiber technology, more and more products combining dual polarization-maintaining fibers or even multiple polarization-maintaining fibers are emerging, which puts forward higher requirements for related alignment technology. As a result, the existing polarization-maintaining fiber alignment technology cannot effectively meet the requirements, and there is an urgent need to design new equipment and technology to meet the needs of practical applications. Summary of the Invention

[0005] In response to one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a polarization-maintaining dual-fiber pigtail and its automatic alignment equipment and method, which can meet the alignment preparation requirements of polarization-maintaining dual-fiber pigtail, realize high-precision preparation of polarization-maintaining dual-fiber pigtail, improve the efficiency and accuracy of multi-core device development and preparation, and reduce the application cost of polarization-maintaining fiber.

[0006] To achieve the above objectives, one aspect of the present invention provides an automatic alignment device for polarization-maintaining dual fiber pigtails, including a body equipped with a worktable; and a capillary fixing block and a corresponding rotary clamping assembly, a curing assembly and an imaging recognition assembly.

[0007] The capillary fixing block has a block-shaped structure, and a capillary receiving hole is opened through the block body for positioning the capillary to be inserted.

[0008] The rotating clamping components are arranged in pairs, used to clamp and fix the two polarization-maintaining optical fibers after they are perforated, and to rotate and adjust them separately after clamping.

[0009] The curing component is disposed between the rotary clamping component and the imaging recognition component, and includes a support block and a curing module; the top of the support block is provided with a mounting position for assembling the capillary fixing block, so that the assembled capillary fixing block can be directly facing the rotary clamping component and the imaging recognition component at both ends of its capillary receiving hole respectively; the curing module is disposed on one side of the support block and is used to promote the curing of the adhesive filling the two axial holes of the capillary.

[0010] The imaging recognition component is located on the side of the curing component away from the rotating clamping component. It is used to identify the capillary receiving hole and the capillary end face and the end faces of the two polarization-maintaining optical fibers after the capillary fixing block is assembled into the support block, so as to provide a basis for the rotation adjustment of the corresponding rotating clamping component.

[0011] As a further improvement of the present invention, a grinding disc is also included;

[0012] The grinding disc has at least one receiving hole for embedding the capillary fixing block, and a connecting hole is provided on one side of the receiving hole;

[0013] Accordingly, a connector is provided on the capillary fixing block corresponding to the connecting hole. The connector can be inserted into the receiving hole at one end of the capillary fixing block with the capillary receiving hole and then match the connecting hole, thereby fixing the capillary fixing block to the grinding disc.

[0014] As a further improvement of the present invention, the connector includes a linear bearing disposed in a through hole on the capillary fixing block and a locking nut with one end matching one end of the linear bearing. By turning the locking nut, the end of the linear bearing away from the locking nut can be locked and connected to the connecting hole.

[0015] As a further improvement of the present invention, an embedding groove is provided on one side of the capillary fixing block, penetrating the middle of the capillary receiving hole, and a locking block with adjustable embedding depth is provided in the fixing groove. By adjusting the embedding depth of the locking block, the capillary in the capillary receiving hole can be pressed or released.

[0016] As a further improvement of the present invention, an elastic buffer is provided on the capillary fixing block corresponding to the locking block for elastic buffering during the process of adjusting the embedding depth of the locking block.

[0017] As a further improvement of the present invention, the rotating clamping assembly includes a fixed base and an optical fiber clamping unit and a rotating bracket disposed on the fixed base;

[0018] The fiber clamping unit has a rod-shaped structure. One end of it is connected to a rotating disk on a rotating support via a rotating shaft, and is used to rotate around the shaft under the drive of the rotating disk. The other end of it has a fixing groove of a certain depth, and a pressure plate is provided corresponding to the fixing groove, so that the polarization-maintaining fiber after being threaded onto the axis can be fixedly clamped on the fiber clamping unit under the pressure of the pressure plate.

[0019] As a further improvement of the present invention, the rotary clamping assembly further includes a sliding unit;

[0020] The rotating bracket is connected to the fixed base through the sliding unit, and can slide back and forth along the axial direction of the fiber optic clamping unit under the drive of the sliding unit.

[0021] As a further improvement of the present invention, the bottom of the support block and / or the imaging recognition component is provided with an adjustable bracket for driving the support block and / or the imaging recognition component to adjust their position in the corresponding direction.

[0022] Another aspect of the present invention provides an automatic alignment method for a polarization-maintaining dual-fiber pigtail, which utilizes the aforementioned automatic alignment device for the polarization-maintaining dual-fiber pigtail. The automatic alignment method includes the following steps:

[0023] (1) Insert a capillary tube into the capillary receiving hole on the capillary fixing block, and assemble the capillary fixing block on the support block so that the two ends of the capillary tube are aligned with the imaging recognition component and the rotating clamping component respectively.

[0024] (2) Control the imaging recognition component to work, set the axial normal and identify the center of the two shaft holes at the end of the capillary, and use the line connecting the centers of the two shaft holes as the reference line.

[0025] (3) Determine whether the angle between the baseline and the axial normal meets the set requirements by the imaging recognition component; if not, rotate the capillary into place;

[0026] (4) Insert the two polarization-maintaining fibers to be aligned into the two axial holes of the capillary until the ends of the two polarization-maintaining fibers protrude from the capillary and face the end of the imaging recognition component; thereafter, clamp and fix the two polarization-maintaining fibers on the corresponding rotating clamping components.

[0027] (5) Control the imaging recognition component to identify the ends of the two polarization-maintaining fibers respectively, identify the two stress regions on the ends of the two polarization-maintaining fibers, and obtain the reference line of each polarization-maintaining fiber end by connecting the centers of the two stress regions at the ends of each polarization-maintaining fiber.

[0028] (6) Identify the angles between the two reference lines and the baseline respectively, and determine whether the two angles meet the requirements of the preset value for the axis; if not, control the corresponding rotating clamping component to drive the polarization-maintaining fiber clamped and fixed by it to rotate until the preset value is met; when the two angles meet the requirements of the preset value for the axis, lock the position of the two rotating clamping components.

[0029] (7) Control the operation of the curing module in the curing assembly to promote the curing of the adhesive liquid filled in the capillary in advance, thereby completing the automatic alignment of the two polarization-maintaining optical fibers in the capillary.

[0030] As a further improvement of the present invention, while controlling the operation of the curing module in process (7), the imaging recognition component is controlled to detect the angle between the reference line and the baseline on the two polarization-maintaining optical fibers in real time.

[0031] If the included angle exceeds the preset value within 10 seconds after the curing module starts working, the corresponding rotating clamping component will be controlled to rotate the polarization-maintaining fiber held and fixed by it by the corresponding angle.

[0032] As a further improvement of the present invention, after completing process (7), the following process is also performed:

[0033] (8) Release the rotating clamping assembly from the two polarization-maintaining optical fibers and remove the capillary fixing block from the support block; keep the capillary fixed in the capillary receiving hole and install the capillary fixing block on the grinding plate to grind the end of the polarization-maintaining optical fiber.

[0034] As a further improvement of the present invention, after the polishing process of the fiber end is completed, the capillary fixing block is removed from the polishing disk and fixed on the support block, and the imaging recognition component is controlled to identify the fiber axial angle and the end face quality of the fiber at the capillary end; thereafter, the capillary fixing block is removed from the support block and the capillary after axial fiber threading is taken out from the capillary receiving hole to obtain the polarization-maintaining dual fiber pigtail that has been prepared.

[0035] In another aspect, the present invention provides a polarization-maintaining dual-fiber pigtail, which is prepared by the automatic alignment method of the polarization-maintaining dual-fiber pigtail, comprising a capillary tube and two polarization-maintaining fibers whose ends have been aligned and fixed in the capillary tube.

[0036] The aforementioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0037] In summary, the beneficial effects of the above-described technical solutions conceived by this invention compared with the prior art include:

[0038] (1) The automatic alignment device for polarization-maintaining dual fiber pigtails of the present invention includes a rotating clamping component, a curing component and an imaging recognition component correspondingly arranged on the worktable. By utilizing the corresponding arrangement of the capillary fixing block and the support block in the curing component, the axial fiber-threading capillary can be reliably fixed. Furthermore, by utilizing the collaborative work of the rotating clamping component and the imaging recognition component, the state of the polarization-maintaining fiber after axial fiber-threading in the capillary can be quickly identified and the fiber position can be quickly adjusted. This effectively ensures the operational accuracy of the polarization-maintaining fiber alignment process, improves the alignment accuracy, yield and product consistency of the product, and reduces the defect rate of polarization-maintaining dual fiber pigtails.

[0039] (2) The automatic alignment device for polarization-maintaining dual fiber pigtails of the present invention utilizes a grinding disc and a capillary fixing block to be correspondingly set and form an alignment grinding assembly, which can realize the end face grinding of the capillary after fiber threading. During the grinding process, the alignment state between the capillary and the capillary fixing block is not changed, avoiding secondary alignment during the end face morphology detection after grinding. This simplifies the process of polarization-maintaining dual fiber pigtail alignment preparation, improves the efficiency and accuracy of polarization-maintaining dual fiber pigtail preparation, and reduces the preparation cost of polarization-maintaining dual fiber pigtails.

[0040] (3) The automatic alignment device for polarization-maintaining dual fiber pigtails of the present invention, through the combination of various components in the rotating clamping assembly, the curing assembly and the imaging recognition assembly, especially the combination of two adjustable brackets and the sliding unit, can realize the flexible adjustment of the relative position of each component during the alignment operation of the two polarization-maintaining fibers, ensure the alignment control accuracy during the alignment operation, and improve the efficiency of product alignment processing.

[0041] (4) The automatic alignment method of polarization-maintaining dual fiber pigtail of the present invention is realized by using an automatic alignment device. The steps are simple and the control is convenient. It can accurately identify the capillary end face and the fiber end face after fiber insertion, and automatically complete the rotation adjustment of the corresponding fiber. It effectively improves the efficiency and accuracy of the alignment of the two polarization-maintaining fibers in the capillary and reduces the preparation cost of polarization-maintaining dual fiber pigtail.

[0042] (5) The automatic alignment device for polarization-maintaining dual fiber pigtails of the present invention has a simple structure, is easy to disassemble and operate, can accurately identify the end face of the two polarization-maintaining fibers when they are aligned and fixed in the capillary, and automatically adjust the alignment angle of the fibers, thereby improving the alignment accuracy and efficiency of the two polarization-maintaining fibers, improving the preparation accuracy of the polarization-maintaining dual fiber pigtails, improving the product preparation yield and performance, and has good application value. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments 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.

[0044] Figure 1 This is a schematic diagram of the overall structure of the automatic alignment device for polarization-maintaining dual-fiber pigtails in this embodiment of the invention.

[0045] Figure 2 This is a structural schematic diagram of the core component of the automatic shaft alignment device in an embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the structure of the rotary clamping assembly of the automatic shaft alignment device in an embodiment of the present invention;

[0047] Figure 4 This is a schematic diagram of the curing component of the automatic shaft alignment device in an embodiment of the present invention;

[0048] Figure 5 This is a schematic diagram of the structure of the shaft grinding component of the automatic shaft alignment device in an embodiment of the present invention;

[0049] Figure 6 This is a schematic diagram of the structure of the automatic alignment device for adjusting the alignment of the polarization-maintaining fiber optic cable in an embodiment of the present invention;

[0050] Figure 7 This is a schematic diagram of the process of using an automatic alignment device to perform polarization-maintaining fiber alignment in an embodiment of the present invention.

[0051] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically:

[0052] 1. Polarization-maintaining fiber; 2. Capillary tube; 3. Body; 4. Rotary clamping assembly; 5. Curing assembly; 6. Imaging and recognition assembly; 7. Axis grinding assembly;

[0053] 11. First polarization-maintaining fiber; 111. First reference line; 12. Second polarization-maintaining fiber; 121. Second reference line; 13. Center line; 21. First shaft hole; 22. Second shaft hole; 23. Baseline; 31. Worktable; 311. Metal horizontal platform; 312. Rotating component base; 32. Support frame; 33. Traveling wheel; 41. Fiber clamping unit; 411. Fixing slot; 412. Pressure plate; 413. Rotating shaft; 42. Rotating bracket; 421. Rotating turntable; 43. Sliding unit; 431. Slide rod; 432. Rotating rod; 43 3. Slider; 44. Fixed base; 45. Control cable; 51. First adjustable bracket; 52. Support block; 53. Curing module; 531. Fixed support frame; 532. UV curing lamp; 61. Second adjustable bracket; 62. CCD camera; 63. Display; 71. Capillary fixing block; 711. Locking nut; 712. Set screw spring; 713. Linear bearing; 714. Capillary receiving hole; 715. Locking screw; 716. Locking block; 717. Elastic buffer; 72. Grinding disc; 721. Receiving groove; 722. Connecting hole. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0055] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0056] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0057] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0058] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0059] Example:

[0060] Please see Figures 1-6 The automatic alignment device for polarization-maintaining dual fiber optic pigtails in a preferred embodiment of the present invention includes a body 3, which includes a support frame 32 and a worktable 31 disposed on the support frame 32. A rotating clamping assembly 4, a curing assembly 5 and an imaging recognition assembly 6 are disposed on the worktable 31.

[0061] In actual operation, the capillary tube 2 used for the fiber threading process is as follows: Figure 6 As shown, it is used for inserting two polarization-maintaining optical fibers 1, namely the first polarization-maintaining optical fiber 11 and the second polarization-maintaining optical fiber 12. The capillary tube 2 has a cylindrical structure, and a pair of through holes are opened along the axial direction inside, namely the first axial hole 21 and the second axial hole 22. The axes of the two axial holes are parallel and are used for inserting and fixing the two polarization-maintaining optical fibers 1, respectively.

[0062] In a preferred embodiment, except for the area where the two shaft holes are opened, the rest of the capillary 2 is a solid structure, and the line connecting the centers of the two shaft holes preferably passes through the center of the capillary 2.

[0063] More specifically, in the preferred embodiment, the support frame 32 is a metal frame with an internal cavity forming a box structure, allowing the necessary equipment for each component to be accommodated and installed in the cavity of the support frame 32. Meanwhile, in the preferred embodiment, the workbench 31 is preferably a marble horizontal platform, positioned on top of the support frame 32, for placing components related to the rotational alignment operation and assisting in completing the corresponding work process.

[0064] Preferably, a plurality of traveling wheels 33 are provided at the bottom of the support frame 32 to support and displace the support frame 32, ensuring that the working position of the equipment can be flexibly adjusted as needed.

[0065] In actual installation, the aforementioned traveling wheels 33 can be configured to have adjustable support height, allowing the horizontal state of the worktable 31 to be adjusted by each traveling wheel 33. Simultaneously, each traveling wheel 33 can also be equipped with a telescopic support structure, enabling reliable support of the support frame 32 to be achieved through adjustment of each telescopic support structure after the traveling wheel 33 has traveled to its designated position.

[0066] like Figure 3 As shown, in the preferred embodiment, the rotating clamping components 4 are arranged in pairs for clamping and rotating the two polarization-maintaining optical fibers 1 to be threaded through the tube.

[0067] Specifically, the rotating clamping assembly 4 includes a rotating bracket 42 and an optical fiber clamping unit 41 disposed on the rotating bracket 42. The optical fiber clamping unit 41 has a rod-shaped structure. One end of the unit is rotatably connected to a rotating turntable 421 mounted on the top of the rotating bracket 42 via a rotating shaft 413. A fixing groove 411 is formed on the surface of the other end. The extending direction of the fixing groove 411 is parallel to the axis of the rotating bracket 42. It is more preferably a V-shaped groove, so that the two polarization-maintaining optical fibers 1 to be aligned can be correspondingly embedded in the V-shaped groove.

[0068] Meanwhile, a pressure plate 412 is provided in the corresponding fixing slot 411 to press the polarization-maintaining fiber 1 into the fixing slot 411 after it is embedded in the fixing slot 411. Accordingly, the two rotating disks 421 are electrically connected to the servo motor through control cables 45, so that the servo motor can control the two rotating disks 421 to rotate accordingly as needed, thereby completing the rotation adjustment of the two polarization-maintaining fibers 1.

[0069] More specifically, in the preferred embodiment, the rotating bracket 42 has a vertical rod-shaped structure, and its top has a through hole corresponding to the rotating shaft 413, so that one end of the rotating shaft 413 can be connected to the end of the optical fiber clamping unit 41, and the other end passes through the through hole and is connected to the rotating turntable 421 fixed on the rotating bracket 42.

[0070] Furthermore, the bottom of the rotating bracket 42 is mounted on the fixed base 44 via the sliding unit 43, so that the rotating bracket 42 can reciprocate under the drive of the sliding unit 43.

[0071] More specifically, in the preferred embodiment, the sliding direction of the sliding unit 43 is preferably parallel to the extension direction of the fixing groove 411, that is, the sliding direction is parallel to the axis of the end of the polarization-maintaining fiber 1 to be perforated. In actual installation, the sliding unit 43 preferably includes two fixing blocks spaced apart on the fixing base 44 and a slider 433 disposed between the two fixing blocks. Corresponding to the two sliders 433, at least one sliding rod 431 is disposed between the two fixing blocks. The slider 433 is slidably sleeved on the sliding rod 431, so that the sliding rod 431 can guide the slider 433 to slide.

[0072] Correspondingly, a rotating rod 432 is also provided on one of the fixed blocks corresponding to the slider 433, which passes through the fixed block and is threadedly connected to it. At the same time, one end of the rotating rod 432 abuts against the end face of the slider 433, and an elastic element, such as a compression spring, is provided on the other side of the slider 433 away from the rotating rod 432, so as to always apply a force to the slider 433 pointing towards the rotating rod 432, thereby keeping the slider 433 pressed against the end of the rotating rod 432.

[0073] With this configuration, the sliding control of the slider 433 can be accurately achieved by adjusting the rotation of the rotating rod 432, thereby completing the telescopic movement control of the optical fiber 1 to be aligned.

[0074] Of course, it is understandable that, in addition to the sliding drive method mentioned above, the sliding unit 43 can also be set to other forms as needed, as long as it can complete the reciprocating extension and retraction of the rotating bracket 42 and the fiber clamping unit 41. This will not be elaborated here.

[0075] Preferably, in actual installation, the two rotating clamping assemblies 4 are preferably mounted on the same fixed base 44. Furthermore, considering the small center-to-center distance between the two shaft holes on the capillary 2, when actually installing the rotating clamping assemblies 4, it is necessary to minimize the distance between the polarization-maintaining fibers 1 clamped on the two rotating clamping assemblies 4. To this end, in a preferred embodiment, the axes of the fiber clamping units 41 of the two rotating clamping assemblies 4 intersect and are arranged at a certain angle, so that the distance between the two fiber clamping units 41 is minimized at the end where the fixing groove 411 is provided. Figure 3 As shown.

[0076] More preferably, the rotating clamping assembly 4 is mounted on the workbench 31 via a fixed base 44. In a preferred embodiment, the workbench 31 is a marble platform. To facilitate the installation of each component, a metal horizontal platform 311 is preferably provided on the workbench 31, and a rotating assembly base 312 is provided on the metal horizontal platform 311 corresponding to the installation of each rotating clamping assembly 4, such as... Figure 2 As shown, the rotary clamping assembly 4 can be quickly installed on the rotary assembly base 312 as needed, and then horizontally installed on the worktable 31 via the metal horizontal platform 311.

[0077] like Figure 4 As shown, in the preferred embodiment, the curing component 5 is disposed on one side of the rotating clamping component 4. It includes a support block 52 for placing the capillary fixing block 71. The support block 52 has a core insertion slot for embedding and installing the capillary fixing block 71, ensuring that the position of the capillary fixing block 71 remains relatively fixed during the core insertion process.

[0078] Meanwhile, in the preferred embodiment, a first adjustable bracket 51 is also provided corresponding to the support block 52. It is preferably a three-dimensional adjustable bracket. The support block 52 is installed on the bracket, and the three-dimensional coordinates can be adjusted by adjusting the bracket, so as to ensure the flexibility of the working position of the support block 52.

[0079] In actual setup, the first adjustable bracket 51 is set on the workbench 31. It is easy to understand that when a metal horizontal platform 311 is set on the workbench 31, the first adjustable bracket 51 is set on the metal horizontal platform 311.

[0080] More specifically, in the preferred embodiment, the curing component 5 further includes a curing module 53 disposed on one side of the support block 52, for acting on the adhesive filling the capillary 2 and promoting its curing.

[0081] In actual setup, the curing module 53 is preferably configured to correspond to the adhesive liquid, which can be a photocuring module or a thermocuring module; correspondingly, the adhesive liquid filling the two axial holes of the capillary 2 is also a photocuring adhesive liquid or a thermocuring adhesive liquid.

[0082] In a preferred embodiment, the curing module 53 is an ultraviolet curing module, which preferably includes a fixed support frame 531 disposed on the workbench 31 and an ultraviolet curing lamp 532 disposed on the fixed support frame 531; correspondingly, the adhesive used for filling is ultraviolet glue. By aligning the ultraviolet curing lamp 532 with the capillary fixing block 71 on the support block 52, ultraviolet light irradiation can be accurately provided and the curing operation of the ultraviolet glue in the two shaft holes of the capillary 2 can be realized.

[0083] Furthermore, in the preferred embodiment, the imaging recognition component 6 is disposed on the side of the curing component 5 away from the rotating clamping component 4, and includes a CCD camera 62 disposed on the second adjustable bracket 61. The lens of the CCD camera 62 is aligned with the capillary fixing block 71 on the support block 52 and is used to observe the end of the capillary 2 fixed on the capillary fixing block 71.

[0084] In actual setup, in order to facilitate the real-time display of the recognition results of the CCD camera 62, it is preferable to set up a display 63 corresponding to the CCD camera 62, which is electrically connected to the CCD camera 62 and can display the image results captured and displayed by the CCD camera 62 in real time.

[0085] More specifically, in the preferred embodiment, the second adjustable bracket 61 is preferably a three-dimensional adjustable support frame, which can realize the position adjustment of the CCD camera 62 in the three-axis directions of XYZ, ensuring the accuracy of the working position of the CCD camera 62.

[0086] Furthermore, in the preferred embodiment, the capillary fixing block 71 is as follows: Figure 5 As shown, it has an irregular (Z-shaped) block structure, including a first fixing part for inserting and fixing the capillary 2 and a second fixing part for fixing the capillary fixing block 71.

[0087] In a preferred embodiment, two fixing parts are disposed at both ends of the capillary fixing block 71, preferably arranged in parallel and forming a Z-shaped structure. A capillary receiving hole 714 is provided through the end face of the first fixing part for the insertion of the capillary 2. Simultaneously, a groove is provided at the end of the first fixing part corresponding to the capillary receiving hole 714, connecting to the middle of the capillary receiving hole 714. A locking block 716 is embedded in the groove, and the locking block 716 presses the capillary inserted into the capillary receiving hole 714 against the inner wall of the receiving hole.

[0088] More specifically, a locking screw 715 is provided corresponding to the locking block 716, and an elastic buffer 717, more preferably a buffer spring, is provided between the locking block 716 and the first fixing part. The locking block 716 can be moved stepwise in the embedded groove by turning the locking screw 715, thereby locking or releasing the capillary tube 2 by the locking block 716.

[0089] Furthermore, in a preferred embodiment, a grinding disc 72 is also provided based on the capillary fixing block 71, and the two together form an axis-to-axis grinding assembly 7, such as... Figure 5 As shown in the image.

[0090] In the preferred embodiment, the grinding disc 72 has a plate-like structure, and a receiving groove 721 is provided on one end face of the disc corresponding to the capillary fixing block 71, so that the first fixing part of the capillary fixing block 71 can be correspondingly embedded in the receiving groove 721, and the second fixing part abuts against the end face of the grinding disc 72.

[0091] More specifically, in the preferred embodiment, the second fixing part has a through hole, in which a linear bearing 713 is embedded, and a locking nut 711 is coaxially embedded in the linear bearing 713. A set screw spring 712 is provided between the end cap of the locking nut 711 and the linear bearing 713. Correspondingly, a connecting hole 722 is provided on the end face of the grinding disc 72 corresponding to the linear bearing 713. By rotating the locking nut 711, the set screw spring 712 can be compressed, thereby adjusting the height of the linear bearing 713, so that the linear bearing 713 is limitedly connected to the connecting hole 722.

[0092] Of course, in addition to the above connection method, the second fixing part and the grinding disc 72 can also be fixed in other ways, such as magnetic fixing or direct threaded connection through the connecting screw that passes through the second fixing part, which will not be elaborated here.

[0093] In the preferred embodiment, the capillary fixing block 71 is embedded in the insert slot and fixed when it is set on the curing component 5, and the axis of the capillary receiving hole 714 is set horizontally; when the capillary fixing block 71 is set in the grinding disc 72, it is matched and locked with the connecting hole 722 by the linear bearing 713.

[0094] In actual installation, the receiving groove 721 is preferably a through groove, allowing the capillary 2 end on the capillary fixing block 71 to protrude, thereby completing the corresponding end grinding. In addition, in specific installation, the receiving groove 721 on the grinding disc 72 is preferably multiple, which can fix multiple capillary fixing blocks 71, thereby realizing the grinding of the ends of multiple capillary 2.

[0095] As another aspect of the present invention, an automatic alignment method for polarization-maintaining dual-fiber pigtails is also provided based on the aforementioned automatic alignment device, the process of which is as follows: Figure 7 As shown, and preferably including the following processes:

[0096] (1) A rotating clamping assembly 4, a curing assembly 5, and an imaging recognition assembly 6 are assembled on the body 3;

[0097] (2) A capillary tube 2 is embedded in the capillary receiving hole 714 on the capillary fixing block 71, and the capillary fixing block 71 is embedded on the support block 52 of the curing component 5, so that the two ends of the capillary tube 2 are aligned with the CCD camera 62 in the imaging recognition component 6 and the optical fiber clamping unit 41 in the rotating clamping component 4, respectively.

[0098] (3) Control the CCD camera 62 in the imaging recognition component 6 to work, and use it to identify the center of the two axial holes at the end of the capillary 2, and use the line connecting the two centers as the reference line 23 (denoted as L1); at the same time, set the axial normal line (denoted as L2) through the imaging recognition component 6.

[0099] In a preferred embodiment, a horizontal straight line (preferably a straight line parallel to the ground) is set as the axial normal.

[0100] (4) The imaging recognition component 6 determines the included angle ϴ1 between L1 and L2, and then determines whether ϴ1 meets the preset value. If it does, the locking screw 715 is turned to lock the capillary tube 2 in place; if it does not meet the preset value, the capillary tube 2 is manually rotated until the preset value requirement is met and then the capillary tube 2 is locked in place.

[0101] In a preferred embodiment, in the fixed capillary 2, the center line connecting the first shaft hole 21 and the second shaft hole 22 is preferably set horizontally, that is, L1 is a horizontal straight line; at this time, the determination range of ϴ1 is ±0.1°.

[0102] In actual operation, after setting up the capillary tube 2, it is preferable to inject a certain amount of UV glue into each of the two shaft holes.

[0103] (5) Insert the two polarization-maintaining optical fibers 1 with one end cut and the end face neat into the first shaft hole 21 and the second shaft hole 22 respectively, so that the ends of the two polarization-maintaining optical fibers 1 protrude slightly from the end of the capillary tube 2 facing the imaging recognition component 6; thereafter, insert the two polarization-maintaining optical fibers 1 into the two fixing slots 411 and press and fix them with the pressure plate 412 respectively.

[0104] (6) The imaging recognition component 6 is controlled to identify the ends of the two polarization-maintaining optical fibers 1 respectively, identify the center of the two polarization-maintaining optical fibers 1 and the two stress regions on the ends, and connect the centers of the two polarization-maintaining optical fibers 1 to obtain the center line 13. In the preferred embodiment, the center line 13 preferably coincides with the reference line 23; at the same time, the centers of the two stress regions at the ends of each polarization-maintaining optical fiber 1 are connected to obtain the reference lines at the ends of the two polarization-maintaining optical fibers 1, namely the first reference line 111 and the second reference line 121, as shown. Figure 6 As shown;

[0105] More specifically, during the actual operation of the imaging recognition component 6, the CCD camera 62 can be focused on the ends of the two polarization-maintaining optical fibers 1 by corresponding adjustment of the second adjustable bracket 61.

[0106] Meanwhile, because the end face of polarization-maintaining fiber 1 has a stress zone, a core, and a cladding, and the refractive indices of these three regions are different, the light transmittance after passing through the fiber is inconsistent. This manifests as different levels of brightness in visual imaging, leading to pixel differences in the image recognized by imaging recognition component 6. The brightest region is the core, the darkest region is the cladding, and the darkest region is the stress zone. This method allows for the identification of different regions. By determining the boundaries of regions with different pixel differences, the circular boundary of the stress zone can be identified, thereby determining the center position of the stress zone and the corresponding reference line.

[0107] (7) Control the imaging recognition component 6 to work and identify the angle ϴ2 between the first reference line 111 and the baseline 23 and the angle ϴ3 between the second reference line 121 and the baseline 23 respectively; thereafter, compare the two angles with the preset value of the polarization maintaining fiber 1 through the axis in the capillary 2 respectively.

[0108] If the comparison result meets the preset requirements, the corresponding fiber clamping unit 41 is locked to prevent the polarization maintaining fiber 1 from rotating during the subsequent curing process.

[0109] If the comparison result does not meet the preset requirements, the corresponding rotating turntable 421 is controlled to work, driving the polarization-maintaining fiber 1 to rotate around the axis at the corresponding angle. After rotating into place, the fiber clamping unit 41 is locked in place.

[0110] (8) Control the operation of the curing component 5, and use the ultraviolet curing lamp 532 to irradiate the ultraviolet glue in the capillary tube 2 to cure it, thereby completing the axial insertion of the two polarization-maintaining optical fibers 1 in the capillary tube 2.

[0111] In a preferred embodiment, while UV curing is being performed, the imaging recognition component 6 identifies the angle between the two reference lines and the baseline 23 in real time. If the angle changes and exceeds the preset value, the corresponding fiber clamping unit 41 is controlled to rotate, thereby ensuring that the polarization-maintaining fiber 1 in the capillary 2 can be cured in the corresponding position.

[0112] Considering that rotating the optical fiber after the UV adhesive has cured to a certain extent will cause torsional damage to the optical fiber, in the preferred embodiment, the optical fiber rotation adjustment during the curing process is preferably controlled within 10 seconds after the curing begins.

[0113] Furthermore, after the two polarization-maintaining fibers 1 are aligned and cured in the capillary tube 2, it is preferable to perform a polishing process on the fiber ends, which includes the following:

[0114] (9) Release the pressure of the two pressure plates 412 on the two polarization-maintaining optical fibers 1, and remove the capillary fixing block 71 from the support block 52. Then, embed the capillary fixing block 71 into the receiving groove 721 on the polishing disc 72, and adjust the locking nut 711 to fix the capillary fixing block 71 to the polishing disc 72. Then, perform the corresponding polishing operation.

[0115] After grinding is completed, the capillary fixing block 71 is preferably removed and embedded in the ferrule slot on the support block 52. The imaging recognition component 6 is controlled to identify the axial angle of the two polarization-maintaining optical fibers 1 at the end of the capillary 2 and to detect whether the end face quality of the optical fiber is qualified. After the above detection is completed, the capillary fixing block 71 is removed, the locking screw 715 is loosened, and the axially aligned capillary 2 is taken out from the capillary fixing block 71, thus completing the preparation of the corresponding polarization-maintaining dual optical fiber pigtail.

[0116] In view of this, as another aspect of the preferred embodiment, a polarization-maintaining dual fiber pigtail prepared according to the aforementioned automatic alignment method is also provided. The polarization-maintaining dual fiber pigtail includes a capillary tube and a polarization-maintaining fiber whose end has been aligned and fixed in the capillary tube.

[0117] The automatic alignment device for polarization-maintaining dual fiber pigtails in this invention has a simple structure, is easy to disassemble and operate, and can accurately identify the end faces of the two polarization-maintaining fibers when they are aligned and fixed in the capillary tube. It can also automatically adjust the alignment angle of the fibers, improve the alignment efficiency and accuracy of the polarization-maintaining fibers, improve the preparation accuracy of the polarization-maintaining dual fiber pigtails, and improve the product's yield and performance. It has good application value.

[0118] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An automatic axis aligning device for polarization maintaining double fiber pigtails, comprising a machine body provided with a workbench; characterized in that, The capillary fixing block, a rotating clamping assembly, a curing assembly, an imaging recognition assembly and a grinding disc are arranged correspondingly; The capillary fixing block is in a block structure, and a capillary accommodating hole is arranged through the block body for positioning the capillary after the capillary is inserted into the hole; The rotating clamping assembly is arranged in pairs for clamping and fixing the two polarization maintaining optical fibers after the capillary is inserted into the hole and rotating adjustment after the clamping. The curing assembly is arranged between the rotating clamping assembly and the imaging recognition assembly, and includes a supporting block and a curing module; the top of the supporting block is provided with a mounting position for assembling the capillary fixing block, and the two ends of the capillary accommodating hole of the capillary fixing block assembled on the supporting block are arranged to face the rotating clamping assembly and the imaging recognition assembly respectively; the curing module is arranged on one side of the supporting block for curing the glue filled in the two axial holes of the capillary. The imaging recognition assembly is arranged on the side of the curing assembly away from the rotating clamping assembly for recognizing the capillary accommodating hole, the end surface of the capillary in the capillary accommodating hole and the end surface of the two polarization maintaining optical fibers after the capillary is inserted into the hole, so as to provide a basis for the rotating adjustment of the rotating clamping assembly. The grinding disc is provided with at least one accommodating hole for embedding the capillary fixing block, and a connecting hole is arranged on one side of the accommodating hole; correspondingly, a connecting piece is arranged on the capillary fixing block corresponding to the connecting hole, and the connecting piece can match the connecting hole after the capillary fixing block is embedded in the accommodating hole with the end provided with the capillary accommodating hole, so as to fix the capillary fixing block on the grinding disc.

2. The apparatus for automatically aligning a polarization maintaining double fiber pigtail according to claim 1, wherein, The connecting piece includes a linear bearing arranged in the through hole of the capillary fixing block and a locking nut matched with one end of the linear bearing, and the linear bearing can be locked to the connecting hole through the end away from the locking nut by rotating the locking nut.

3. The apparatus for automatically aligning a polarization maintaining double fiber pigtail according to claim 1, wherein, An embedding groove is arranged through the middle part of the capillary accommodating hole on one side of the capillary fixing block, and a locking block with adjustable embedding depth is arranged in the embedding groove, so that the capillary in the capillary accommodating hole can be compressed or released by adjusting the embedding depth of the locking block.

4. The apparatus for automatically aligning a polarization maintaining double fiber pigtail according to claim 3, wherein, A elastic buffer is arranged on the capillary fixing block corresponding to the locking block for elastic buffering during the adjustment of the embedding depth of the locking block.

5. The apparatus for automatically aligning a polarization maintaining double fiber pigtail according to any one of claims 1-4, characterized in that, The rotating clamping assembly includes a fixed base, an optical fiber clamping unit arranged on the fixed base and a rotating support; The optical fiber clamping unit is in a rod structure, one end of which is connected with a rotating disc arranged on the rotating support through a rotating shaft for rotating around the shaft under the driving of the rotating disc, and the surface of the other end is provided with a fixed groove with a certain depth, and a pressing plate is arranged corresponding to the fixed groove, so that the two polarization maintaining optical fibers after the capillary is inserted into the hole can be clamped and fixed on the optical fiber clamping unit under the pressing of the pressing plate.

6. The apparatus for automatically aligning a polarization maintaining double fiber pigtail of claim 5, wherein, The rotating clamping assembly further includes a sliding unit; The rotating support is connected with the fixed base through the sliding unit and can reciprocally slide along the axial direction of the optical fiber clamping unit under the driving of the sliding unit.

7. The apparatus for automatically aligning a polarization maintaining double fiber pigtail according to any one of claims 1-4, 6, wherein, The bottom of the support block and / or the imaging recognition assembly is provided with an adjustable support for driving the support block and / or the imaging recognition assembly to adjust the position in the corresponding direction.

8. A method for automatically aligning a polarization maintaining double fiber pigtail, which is implemented using the polarization maintaining double fiber pigtail automatic alignment apparatus according to any one of claims 1 to 7, characterized by, The automatic axis aligning method comprises the following processes: (1) embedding a capillary into a capillary accommodating hole on a capillary fixing block, and assembling the capillary fixing block on a support block, so that the two ends of the capillary are respectively aligned with an imaging recognition assembly and a rotating clamping assembly; (2) controlling the imaging recognition assembly to work, setting an axial normal line and recognizing the centers of the two axial holes at the ends of the capillary, and taking the line connecting the centers of the two axial holes as a reference line; (3) determining whether the included angle between the reference line and the axial normal line meets the set requirement through the imaging recognition assembly; if not, rotating the capillary to the position; (4) embedding two polarization maintaining optical fibers to be aligned into the two axial holes of the capillary respectively until the ends of the two polarization maintaining optical fibers protrude from the capillary and are opposite to one end of the imaging recognition assembly; thereafter, clamping and fixing the two polarization maintaining optical fibers on the corresponding rotating clamping assemblies respectively; (5) controlling the imaging recognition assembly to recognize the ends of the two polarization maintaining optical fibers respectively, recognizing two stress regions on the ends of the polarization maintaining optical fibers, and obtaining reference lines of the ends of the polarization maintaining optical fibers from the line connecting the centers of the two stress regions of each end of the polarization maintaining optical fiber; (6) recognizing the included angles between the two reference lines and the reference line respectively, determining whether the two included angles meet the requirement of the preset value of the axis alignment; if not, controlling the corresponding rotating clamping assembly to rotate the polarization maintaining optical fiber clamped and fixed thereby until the requirement of the preset value is met; when the two included angles meet the requirement of the preset value of the axis alignment, locking the positions of the two rotating clamping assemblies; (7) controlling a curing module in a curing assembly to work, and promoting the glue liquid filled in the capillary in advance to cure, thereby completing the automatic axis alignment of the two polarization maintaining optical fibers in the capillary.

9. The method of automatically aligning a polarization maintaining double fiber pigtail of claim 8, wherein, While controlling the curing module to work in process (7), the imaging recognition assembly is controlled to detect the included angles between the reference lines and the reference line on the two polarization maintaining optical fibers in real time; Within 10 seconds after the curing module starts to work, if the included angles exceed the preset value, the corresponding rotating clamping assembly is controlled to rotate the polarization maintaining optical fiber clamped and fixed thereby by a corresponding angle.

10. The method of automatically aligning a polarization maintaining double fiber pigtail according to claim 8 or 9, characterized in that, After process (7) is completed, the following process is further performed: (8) releasing the clamping of the two polarization maintaining optical fibers by the rotating clamping assemblies, and taking the capillary fixing block off the support block; keeping the capillary fixed in the capillary accommodating hole, and installing the capillary fixing block in a grinding disc to grind the ends of the polarization maintaining optical fibers.

11. The method of automatically aligning a polarization maintaining double fiber pigtail of claim 10, wherein, After the grinding process of the fiber ends is completed, the capillary fixing block is taken off the grinding disc and fixed on the support block, the imaging recognition assembly is controlled to recognize the fiber axis alignment angle of the capillary end and the end face quality of the fiber; thereafter, the capillary fixing block is taken off the support block and the capillary after the fiber alignment is taken out of the capillary accommodating hole, and a prepared polarization maintaining double fiber pigtail is obtained.

12. A polarization maintaining double fiber pigtail, characterized by, The polarization maintaining dual-fiber pigtail is prepared by the automatic axis alignment method of the polarization maintaining dual-fiber pigtail according to any one of claims 8-11, and comprises a capillary tube and two polarization maintaining optical fibers whose end portions have been aligned in the capillary tube and fixed.

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