Miniaturized polarization-maintaining laser welding machine and method based on cat eye countershaft technology

Abstract

The invention discloses a miniaturized polarization-maintaining laser fusion splicer and method based on a cat eye countershaft technology, and relates to the technical field of fusion splicers. The laser fusion splicer comprises an optical platform, a laser heat source module, a side surface imaging module, an end surface imaging module, a control module and an optical fiber clamping driving mechanism; the optical fiber clamping driving mechanism is used for clamping and driving the left optical fiber and the right optical fiber to perform multi-degree-of-freedom movement; the end face imaging module comprises an integrated double-inclined-plane prism and a camera; the integrated double-inclined-surface prism is integrally formed, and a fixed space included angle is formed by the first reflecting surface and the second reflecting surface of the integrated double-inclined-surface prism. According to the invention, the structure can be simplified, the calibration difficulty is reduced, the operation efficiency is improved, and equipment miniaturization is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fusion splicer, in particular to a miniaturized polarization maintaining laser fusion splicer and method based on cat-eye axis alignment technology. BACKGROUND

[0002] The fusion quality of polarization maintaining optical fiber is highly dependent on the precise alignment of the fiber polarization axis. The core difficulty lies in achieving sub-micron alignment accuracy and zero deviation of the polarization angle. To this end, the prior art has proposed various axis alignment schemes based on the cat-eye imaging principle.

[0003] Currently, an advanced laser fusion splicer scheme (as disclosed in CN120779528A) adopts a layered architecture and double-prism end-face imaging technology. This scheme first performs coarse alignment of the X, Y, and Z axes of the optical fiber through a side imaging module; then, it drives the two optical fibers to separate axially and translate laterally to create space, and moves an electric displacement platform carrying two independent right-angle prisms between the two optical fibers; it uses the two prisms to reflect the "cat-eye" images of the left and right fiber end faces to different side cameras, thereby identifying and adjusting the polarization axis angle; after completing the axis alignment, the double-prism module needs to be moved out, and finally the laser fusion is performed.

[0004] However, the above prior art scheme still has the following limitations: Complex structure, high cost: Two independent prisms and an electric platform to drive the whole movement are used, resulting in more optical and mechanical components, increasing the complexity and manufacturing cost of the system.

[0005] Complicated calibration, stability challenge: The optical paths of the two independent prisms need to be precisely calibrated separately to ensure imaging symmetry. Over time, the relative positions of the two prisms may be disturbed due to vibration or temperature changes, affecting the stability of the alignment accuracy.

[0006] Multiple operation steps, room for improvement in efficiency: The imaging process requires multiple additional steps such as fiber lateral movement, prism module movement in, imaging, prism module movement out, and fiber reset, affecting the overall efficiency of the fusion period.

[0007] Not conducive to device miniaturization: The additional prism movement module occupies a large space, which contradicts the trend of high integration and miniaturization.

[0008] Therefore, there is an urgent need for a new polarization maintaining fiber fusion axis alignment scheme that can significantly simplify the structure, reduce the calibration difficulty, improve the operation efficiency, and facilitate the realization of device miniaturization while ensuring or even improving the alignment accuracy and stability. SUMMARY

[0009] The purpose of this invention is to provide a miniaturized polarization-maintaining laser fusion splicer and method based on cat's eye alignment technology, so as to solve the problems existing in the prior art, simplify the structure, reduce the calibration difficulty, improve the operating efficiency, and facilitate the miniaturization of the equipment.

[0010] To achieve the above objectives, the present invention provides the following solution: This invention provides a miniaturized polarization-maintaining laser fusion splicer based on cat's-eye alignment technology, comprising an optical platform, a laser heat source module, a side imaging module, an end-face imaging module, a control module, and a fiber clamping and driving mechanism. The fiber clamping and driving mechanism is used to clamp the left and right optical fibers and can drive them to perform multi-degree-of-freedom relative motion to achieve three-dimensional spatial alignment and axial separation and approach. The end-face imaging module includes an integrated double-bevel prism and a camera. The integrated double-bevel prism is integrally formed, with its first and second reflecting surfaces forming a fixed spatial angle. The device is configured such that when the left and right optical fibers separate axially, it can move between their end faces, so that the first reflective surface faces the end face of the left optical fiber and the second reflective surface faces the end face of the right optical fiber; the camera is used to receive the cat's-eye image of the end faces of the left and right optical fibers via the first and second reflective surfaces; the input end of the control module is communicatively connected to the output end of the camera to receive the cat's-eye image; the output end of the control module is communicatively connected to the control end of the optical fiber clamping drive mechanism to output a control signal for polarization axis alignment to the optical fiber clamping drive mechanism.

[0011] Preferably, the end-face imaging module further includes a motor slide module, and the integrated double-bevel prism is fixedly mounted on the motor slide module. The motor slide module is used to drive the integrated double-bevel prism to move in a direction perpendicular to the optical fiber axis, so as to realize the movement of the integrated double-bevel prism between the end faces of the left and right optical fibers and from between them.

[0012] Preferably, the laser heat source module includes a CO2 laser and a beam guiding component. The beam guiding component divides the laser beam generated by the CO2 laser into two beams and focuses them symmetrically onto the fusion splice of the optical fiber. The angle between the two laser beams is greater than 170° and less than 180°.

[0013] Preferably, the fiber optic clamping drive mechanism includes: A right fiber clamping unit for clamping and driving the right fiber includes a right rotary motor module and a right motor XYZ motor module for driving the module to perform three-dimensional translation. A left fiber clamping unit for clamping and driving the left fiber includes a left fiber clamping module and a left XYZ motor module for driving the module to perform three-dimensional translation. At least one of the right fiber clamping unit and the left fiber clamping unit is integrated with a rotary motor capable of driving the fiber to rotate around its own axis.

[0014] Preferably, the side imaging module includes a first side camera and a second side camera, which are respectively disposed on both sides of the fusion splice area along different directions, for imaging the side of the optical fiber. The first side camera is configured to also be used as the camera in the end-face imaging module to receive the cat's eye image obtained by the bend of the integrated double-bevel prism.

[0015] Preferably, the fiber clamping drive mechanism is equipped with replaceable clamps to accommodate different specifications of optical fibers with cladding diameters ranging from 125 μm to 400 μm.

[0016] Preferably, the position adjustment accuracy of the fiber clamping drive mechanism is not less than 0.05μm.

[0017] Preferably, the overall dimensions of the welding machine are no more than 500mm × 345mm × 270mm, and its weight is no more than 80kg.

[0018] Preferably, the second side camera and the first side camera are respectively arranged on both sides of the fusion area. Both the first side camera and the second side camera are fixedly mounted on a camera mount. The length direction of the CO2 laser is parallel to the length direction of the optical platform and is fixedly mounted on the optical platform. The beam guiding assembly includes a mirror group, a first mirror, a beam splitter, and two second mirrors. The mirror group includes two mirrors for receiving the laser beam emitted by the CO2 laser and reflecting the laser beam along opposite but parallel optical paths to change its position in the first plane before guiding it to the first mirror. The first mirror reflects the received laser beam through a perforation on the camera mount to the beam splitter. The beam splitter splits the incident laser beam into a transmitted beam and a reflected beam, and guides them to the two second mirrors respectively. The two second mirrors reflect and focus the two received laser beams onto the fusion area.

[0019] The present invention also provides a fiber optic fusion splicing method, which utilizes a miniaturized polarization-maintaining laser fusion splicer based on the cat's-eye alignment technology as described above, and includes the following steps: a) Based on the image acquired by the side imaging module, control the fiber clamping drive mechanism to achieve initial alignment of the left and right optical fibers in three-dimensional space; b) Control the fiber clamping drive mechanism to separate the end faces of the left and right fibers, which have been initially aligned, from each other along the axial direction. c) Move the integrated double-bevel prism between the end faces of the left and right optical fibers, and make the first reflecting surface face the end face of the left optical fiber and the second reflecting surface face the end face of the right optical fiber. d) The camera simultaneously receives cat's-eye images from the left and right fiber ends, which are refracted through the first and second reflective surfaces. e) Based on the cat's eye image, drive the fiber clamping drive mechanism to adjust the rotation angle of at least one fiber to complete the alignment of the polarization axis of the polarization-maintaining fiber; f) Control the fiber clamping drive mechanism to bring the two fibers that have completed polarization axis alignment closer to each other along the axial direction until they are docked; g) Control the laser heat source module to emit lasers toward the two fiber optic docking points.

[0020] The present invention achieves the following technical effects compared to the prior art: This embodiment achieves fundamental structural simplification by employing an integrated double-bevel prism combined with a single camera, and using an alignment process where the prism is inserted after axial separation of the optical fiber. Since the two reflective surfaces are integrated into a single optical element, their relative position is permanently guaranteed by manufacturing precision, eliminating the need for complex independent calibration of the two optical paths required by dual independent prism schemes. This fundamentally eliminates the problem of alignment accuracy attenuation caused by calibration errors or relative displacement over long-term use. Simultaneously, the axial separation rather than lateral translation step makes the fiber movement trajectory more direct, reducing unnecessary spatial movement. Combined with the setting of a single camera simultaneously acquiring dual-path images, it lowers the requirements for control timing and image processing synchronization, thereby improving system stability and alignment efficiency, laying the foundation for overall miniaturization and highly reliable operation of the equipment. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the 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.

[0022] Figure 1 This is a schematic diagram of the structure of a miniaturized polarization-maintaining laser fusion splicer based on cat's eye alignment technology provided in an embodiment of the present invention; Figure 2 for Figure 1 A schematic diagram of the structure of the middle component; Figure 3 for Figure 2 A view from another direction; Figure 4 for Figure 1 A view from another direction; Figure 5 for Figure 4 Enlarged view of the structure at point A in the middle; Figure 6 for Figure 4 A view from another direction; In the diagram: 1-CO2 laser; 2-reflector group; 3-two-dimensional adjustment frame; 4-first reflector; 5-first side camera mounting bracket; 6-first side camera; 7-second side camera mounting bracket; 8-right fiber clamping unit; 9-rotary motor; 10-optical platform; 11-motor slide module; 12-motor slide module support frame; 13-integrated double-bevel prism; 14-left fiber clamping unit; 15-left fiber support block; 16-beam splitter; 17-second reflector; 18-second reflector adjustment block; 19-adjustment block mounting bracket; 20-perforation; 21-left fiber; 22-right fiber; 23-fusion splice area; 24-virtual camera optical axis; 25-second side camera. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The purpose of this invention is to provide a miniaturized polarization-maintaining laser fusion splicer and method based on cat's eye alignment technology, so as to solve the problems existing in the prior art, simplify the structure, reduce the calibration difficulty, improve the operating efficiency, and facilitate the miniaturization of the equipment.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] The following is combined Figures 1 to 6 The following describes embodiments of the present invention.

[0027] Example 1 This invention provides a miniaturized polarization-maintaining laser fusion splicer based on cat's-eye alignment technology, comprising an optical platform 10, a laser heat source module, a side imaging module, an end-face imaging module, a control module, and a fiber clamping drive mechanism. The fiber clamping drive mechanism is used to clamp the left fiber 21 and the right fiber 22 and can drive them to perform relative motion with multiple degrees of freedom to achieve three-dimensional spatial alignment and axial separation and approach. The end-face imaging module includes an integrated double-bevel prism 13 and a camera. The integrated double-bevel prism 13 is integrally formed, and its first reflective surface and second reflective surface form a fixed spatial angle. The integrated double-bevel prism 13 is configured such that when the left fiber 21 and the right fiber 22 are separated axially, it can move between their end faces, so that the first reflective surface faces the end face of the left fiber 21 and the second reflective surface faces the end face of the right fiber 22. The camera is used to receive the cat's-eye images of the end faces of the left fiber 21 and the right fiber 22 obtained by the first reflective surface and the second reflective surface.

[0028] The control module is configured to perform the following cat's eye alignment process: a) Based on the image acquired by the side imaging module, control the fiber clamping drive mechanism to achieve initial alignment of the left fiber 21 and the right fiber 22 in three-dimensional space; b) Control the fiber clamping drive mechanism to separate the end faces of the initially aligned left fiber 21 and right fiber 22 from each other along the axial direction; c) Move the integrated double-bevel prism 13 between the end faces of the left fiber 21 and the right fiber 22, and make the first reflecting surface face the end face of the left fiber 21 and the second reflecting surface face the end face of the right fiber 22; d) Simultaneously receive the cat's eye images of the end faces of the left fiber 21 and the right fiber 22 through the camera, which are turned by the first reflecting surface and the second reflecting surface; e) Drive the fiber clamping drive mechanism to adjust the rotation angle of at least one fiber according to the cat's eye image to complete the alignment of the polarization axis of the polarization-maintaining fiber.

[0029] This embodiment achieves fundamental structural simplification by combining an integrated double-bevel prism 13 with a single camera and employing an alignment process where the prism is inserted after axial separation of the optical fiber. Since the two reflecting surfaces are integrated into a single optical element, their relative position is permanently guaranteed by manufacturing precision, eliminating the need for complex independent calibration of the two optical paths required by dual independent prism schemes. This fundamentally eliminates the problem of alignment accuracy attenuation caused by calibration errors or relative displacement during long-term use. Simultaneously, the axial separation rather than lateral translation step makes the optical fiber movement trajectory more direct, reducing unnecessary spatial movement. Combined with the setting of a single camera simultaneously acquiring dual-path images, it lowers the requirements for control timing and image processing synchronization, thereby improving system stability and alignment efficiency, laying the foundation for overall miniaturization and highly reliable operation of the equipment.

[0030] In some embodiments, the end-face imaging module further includes a motor slide module 11, on which an integrated double-slanted prism 13 is fixedly mounted. The motor slide module 11 is used to drive the integrated double-slanted prism 13 to move in a direction perpendicular to the optical fiber axis, so as to realize the insertion and removal in step c).

[0031] In this embodiment, the integrated double-sloping prism 13 is driven to translate by the motor slide module 11, thereby realizing the automation and high-precision positioning of the prism's insertion and removal process.

[0032] The driving method is not limited to motor slides. Depending on cost and accuracy requirements, pneumatic slides, piezoelectric ceramic drive platforms, or precision cam linkage mechanisms can also be used to move and position the prism.

[0033] The motor slide module 11 is fixed on the optical platform 10 by the motor slide module support frame 12.

[0034] In some embodiments, the laser heat source module includes a CO2 laser 1 and a beam guiding component. The beam guiding component splits the laser beam generated by the CO2 laser 1 into two beams and focuses them symmetrically onto the splice point of the optical fiber. The angle between the two laser beams is greater than 170° and less than 180°.

[0035] This embodiment specifies a near 180° symmetrical dual-beam CO2 laser heating method. This design creates a uniform thermal field around the fiber, which significantly reduces thermal deformation and residual stress at the fusion joint compared to single-sided heating. Compared to a more complex four-beam system, it greatly simplifies the optical path, reduces the number of components, and enables miniaturization. Furthermore, the non-180° symmetrical dual-beam laser heating aims to avoid light pollution caused by mutual reflection of laser light onto the other mirror when the two mirrors are arranged symmetrically at 180°, thus preventing the mirrors from returning the laser light to the laser source and damaging it.

[0036] The angle between the two laser beams can be optimized and adjusted according to the optimal fusion temperature field of different optical fiber materials, and is not strictly limited to 170°-180°. For example, for some specially coated optical fibers, an angle of 150°-170° may be more optimal.

[0037] In some embodiments, the fiber optic clamping drive mechanism includes: The right fiber clamping unit 8 for clamping and driving the right fiber 22 includes a right rotary motor 9 module and a right motor XYZ motor module for driving the module to perform three-dimensional translation. The left fiber clamping unit 14 for clamping and driving the left fiber 21 includes a left fiber 21 clamping module and a left XYZ motor module for driving the module to perform three-dimensional translation. At least one of the right fiber clamping unit 8 and the left fiber clamping unit 14 is integrated with a rotary motor 9 capable of driving the fiber to rotate around its own axis.

[0038] This embodiment concretizes the fiber clamping drive mechanism into a modular structure with independent left and right sides and symmetrical functions. Each unit integrates three-dimensional translation (XYZ) function, and at least one unit integrates rotation function, collectively achieving a complete six-degree-of-freedom adjustment capability for the fiber. This modular design facilitates assembly, debugging, and maintenance. The explicit inclusion of rotation function in at least one unit covers polarization axis alignment strategies that allow rotation of only one fiber or both fibers, providing operational flexibility and serving as a key execution guarantee for achieving high-precision cat's-eye alignment.

[0039] The drive mechanism can also be implemented using other mechanical structures, such as parallel mechanisms (like the Stewart platform) to provide six degrees of freedom of motion simultaneously. Alternatively, for further miniaturization, the rotary motor 9 can be integrated into the Z-axis translation module to form a compact four-degree-of-freedom module.

[0040] In a specific embodiment, the right optical fiber 22 is equipped with a rotation function, that is, a rotation motor 9. Since the left optical fiber 21 does not have a rotation function, a left optical fiber support block 15 is required to raise the height of the clamp holding the left optical fiber 21.

[0041] In addition, in some examples, one of the right fiber clamping unit 8 and the left fiber clamping unit 14 can be set as a component without lifting and forward / backward movement power, which can only move left and right. During operation, the other clamping unit with power is used to drive the fiber on it to move to align with the fiber fixed in the front and back and up and down positions.

[0042] In some embodiments, the side imaging module includes a first side camera 6 and a second side camera 25, which are respectively disposed on both sides of the fusion splice area 23 in different directions for imaging the side of the optical fiber; wherein, the first side camera 6 is configured to be used as a camera in the end face imaging module to receive the cat's eye image obtained by the integrated double bevel prism 13.

[0043] The core of this embodiment lies in the reuse of hardware resources. The first side camera 6, used for coarse side alignment, also functions as a cat's eye imaging camera, eliminating the need for a separate camera, lens, and mounting structure. This directly brings significant advantages such as reduced hardware costs, simplified system structure, and miniaturization of the overall device. Simultaneously, since side imaging and end-face imaging share part of the optical path and the same image sensor, it reduces calibration errors and alignment deviations that might be introduced by a separate imaging system, helping to improve the consistency of the overall system accuracy.

[0044] Of course, the second side camera 25 can also be reused as the cat's eye imaging camera. Alternatively, in high-end models, to pursue the best image quality, a third dedicated high-resolution camera can be set up specifically for cat's eye imaging, completely separate from the side imaging camera.

[0045] Figure 1 The diagram illustrates the virtual camera optical axes 24 of two cameras, both focused on the fusion splice area 23. It can be understood that the extension direction of the edge of the integrated double-bevel prism 13 is perpendicular to the virtual camera optical axis 24, so that the camera can capture images of the two bevels of the integrated double-bevel prism 13 along a direction perpendicular to one edge of the integrated double-bevel prism 13. This can then be displayed in the control module or on the monitor as two cat's eyes located on both sides of the edge. The two cat's eyes can be made symmetrical about the edge by adjusting the rotation angle of one of the optical fibers.

[0046] In some embodiments, the fiber clamping drive mechanism is equipped with replaceable clamps to accommodate different specifications of optical fibers with cladding diameters ranging from 125 μm to 400 μm.

[0047] This embodiment, through its replaceable clamp design, endows the device with strong compatibility and scalability. By replacing different clamp modules, users can enable the same device to handle various specifications, from conventional communication optical fibers (125μm) to large laser optical fibers (400μm), greatly expanding the application scenarios of the device and avoiding the cost of repeatedly purchasing dedicated equipment due to different fiber specifications. This significantly improves the product's market competitiveness and the user's return on investment.

[0048] In addition to mechanically replaceable clamps, adaptive clamps can also be designed, such as using flexible materials or V-grooves with micro-adjustment mechanisms, so that they can automatically adapt to different optical fibers within a certain diameter range, but this may come at the cost of sacrificing some clamping rigidity and accuracy.

[0049] In some embodiments, the position adjustment accuracy of the fiber clamping drive mechanism is not less than 0.05μm, and the motor that makes up the drive mechanism can be a motor of model 1, XA04A-R102; 2, XA04A-R102-R; 3, ZA04A-W101; 4, ZA04A-W101-R, etc., produced by Shenjin Precision Machinery Co., Ltd.

[0050] This embodiment clarifies the ultra-high motion accuracy achieved by the present invention using a quantitative indicator (not less than 0.05 μm). This accuracy is the physical basis for achieving sub-micron-level alignment of polarization-maintaining fibers and ultimately achieving low-loss fusion splicing. The high-precision translation mechanism ensures that the fiber position error is controlled within an extremely small range during the coarse alignment stage, creating superior conditions for subsequent image-based fine angle alignment. It is one of the core technical indicators to ensure that the final fusion splicing quality meets the requirements of high-end applications.

[0051] For different levels of equipment, this accuracy indicator can be a range, for example, 0.1μm for economical equipment and 0.02μm for high-end equipment. Different levels of accuracy can be achieved by using grating rulers, encoders, or laser interferometers with different accuracy levels as position feedback elements.

[0052] In some embodiments, the overall dimensions of the welding machine are no greater than 500mm × 345mm × 270mm, and its weight is no more than 80kg.

[0053] This embodiment highlights the significant advantages of miniaturization and lightweight design of the invention by limiting the maximum external dimensions and weight of the device. Its compact size makes it easy to install on a standard workbench or bring it into the field, saving valuable laboratory or production workshop space. The lighter weight enhances the device's portability and deployment flexibility. This miniaturized design is a direct reflection of the invention's high integration concept and a key technological achievement.

[0054] With optimization of the internal layout (such as using more compact motors or optical components), size and weight can be further reduced. For stationary industrial applications, the rigidity and stability of the equipment can also be enhanced by using thicker materials without significantly increasing the size.

[0055] In some embodiments, the second side camera 25 and the first side camera 6 are respectively arranged on both sides of the welding area 23. The first side camera 6 and the second side camera 25 are both fixedly mounted on the camera mount. The length direction of the CO2 laser 1 is parallel to the length direction of the optical platform 10 and is fixedly mounted on the optical platform 10. The beam guiding assembly includes a mirror group 2, a first mirror 4, a beam splitter 16, and two second mirrors 17. The mirror group 2 includes two mirrors for receiving the laser beam emitted by the CO2 laser 1 and reflecting the laser beam along opposite but parallel optical paths to change its position in the first plane before guiding it to the first mirror 4. The first mirror 4 reflects the received laser beam through a perforation 20 on the camera mount to the beam splitter 16. The perforation 20 is opened on the first side camera mount 5. The beam splitter 16 splits the incident laser beam into a transmitted beam and a reflected beam, and guides them to the two second mirrors 17 respectively. The two second mirrors 17 reflect and focus the two received laser beams onto the welding area 23.

[0056] This embodiment describes a highly integrated and optimized optomechanical implementation. The CO2 laser 1 is arranged parallel to the platform, making full use of the base plate space. The clever use of the perforation 20 on the camera mount as the laser beam path channel is a prime example of space reuse and structural simplification, eliminating the need for a separate long-distance support for the laser. The entire optical path, from the laser to the fusion point, undergoes careful folding and turning, achieving a symmetrical and stable dual-beam heating optical path within an extremely limited space. This is a concrete and crucial engineering solution for achieving the "miniaturization" goal of this invention.

[0057] The optical path layout can be adaptively adjusted according to the actual size of the optical components used. For example, the perforation 20 structure can be replaced by integrating a small mirror on the mounting bracket to deflect the optical path. The beam splitter 16 can also be placed in other positions, and the optical path can be constructed by increasing the number of mirrors.

[0058] In some embodiments, the beam splitter 16 is a semi-transparent, semi-reflective lens with a beam splitting ratio of 50:50. This configuration ensures that the laser energy received on both sides of the fusion region 23 is the same, thereby improving the fusion quality.

[0059] In some embodiments, considering the error in the installation accuracy of the first reflector 4, in this embodiment, the first reflector 4 and its mount are disposed on the two-dimensional adjustment frame 3. The two-dimensional adjustment frame 3 is used to realize the position adjustment of the first reflector 4 in the up-down and left-right directions, so that the laser beam mirror first reflector 4 can accurately enter the subsequent optical components after reflection, such as the perforation 20 on the camera mount.

[0060] In some embodiments, the second reflector 17, i.e., its mount, is mounted on the second reflector adjusting block 18. The second reflector adjusting block 18 enables two-dimensional adjustment of the second reflector 17, i.e., adjustment in the left-right direction and vertical direction (i.e., upward or downward). The second reflector adjusting block 18 is fixedly mounted on the adjusting block fixing bracket 19.

[0061] In some embodiments, prior to dissolution, the control module can also control the two optical fibers to move to a distance a between the two end faces, where a is smaller than the diameter of the laser beam ultimately emitted to the dissolution region; the control module can control the laser heat source module to emit laser to clean the end faces of the two optical fibers.

[0062] In some embodiments, the camera is a CCD camera.

[0063] In some embodiments, the cameras on both sides can also collect image information in real time during the welding process. The control module can determine key parameters such as the cat's eye's angle deviation from the axis online and feed the information back to the control system. The control system can adjust the welding parameters in a timely manner based on the feedback to ensure the stability and quality of the welding process. At the same time, the operator can also view the welding status in real time through the operation interface, which is convenient for timely detection and handling of abnormal problems.

[0064] In some embodiments, the laser heat source module uses a 10.6µm diameter laser beam as its energy source, with a stable laser power of 40W. The heating source is stable, and the temperature fluctuation range is small, which can ensure the consistency and reliability of the weld.

[0065] In the above embodiments, the two-dimensional adjustment of the first reflector 4 and the second reflector 17 can be implemented using any adjustment scheme known in the art.

[0066] In summary, the equipment provided in this embodiment has a high degree of automation. From fiber cleaning and alignment to splicing, everything can be completed automatically under the control of the control system without much manual intervention. This not only reduces the workload of operators and minimizes human error, but also significantly improves production efficiency, making it suitable for mass production scenarios.

[0067] Example 2 The present invention also provides an optical fiber fusion splicing method, which utilizes a miniaturized polarization-maintaining laser fusion splicer based on cat's-eye alignment technology as described in Embodiment 1, and includes the following steps: a) Based on the image acquired by the side imaging module, control the fiber clamping drive mechanism to achieve initial alignment of the left fiber 21 and the right fiber 22 in three-dimensional space. b) Control the fiber clamping drive mechanism to separate the end faces of the left fiber 21 and right fiber 22, which have completed the initial alignment, from each other along the axial direction. c) Move the integrated double-bevel prism 13 between the end faces of the left fiber 21 and the right fiber 22, and make the first reflecting surface face the end face of the left fiber 21 and the second reflecting surface face the end face of the right fiber 22 (specifically, they abut each other, that is, after the left fiber 21 and the right fiber 22 are separated to a set distance, drive the integrated double-bevel prism 13 to move between the two fibers until the two bevels contact the end faces of the two fibers respectively). d) Simultaneously receive the cat's eye images from the end faces of the left optical fiber 21 and the right optical fiber 22, which are transformed by the first and second reflective surfaces, through the camera. e) Based on the cat's eye image, drive the fiber clamping drive mechanism to adjust the rotation angle of at least one fiber to complete the alignment of the polarization axis of the polarization-maintaining fiber. f) Control the fiber clamping drive mechanism to bring the two fibers that have completed polarization axis alignment closer to each other along the axial direction until they are docked; g) Control the laser heat source module to emit lasers toward the two fiber optic docking points.

[0068] This embodiment claims protection for the method corresponding to the device invention. This method fully describes a standardized and automated process for polarization-maintaining fiber fusion splicing using the fusion splicer of this invention. The method integrates key steps such as side coarse alignment, axial separation, single-prism intervention cat's-eye fine alignment, and final butt welding, resulting in a clear and efficient process. In particular, steps b to e define the unique cat's-eye alignment method of this invention, which can systematically and accurately solve the most difficult angle alignment problem in polarization-maintaining fiber fusion splicing, ensuring that the method can ultimately reproduce the high-quality splicing effect brought about by the device invention.

[0069] Based on the method steps described above, some auxiliary or optimization steps can be added. For example, a fiber end face cleaning and inspection step can be added before step g; a step to verify the alignment result based on the cat's eye image can be added after step e and before step f; or in step g, the laser power and heating time can be dynamically adjusted according to the fiber type.

[0070] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A miniaturized polarization maintaining laser welding machine based on cat-eye pair-axis technology, comprising an optical platform, a laser heat source module, a side imaging module, an end face imaging module and a control module, characterized in that, Also comprising: a fiber clamping driving mechanism for clamping the left and right optical fibers and enabling multi-degree-of-freedom relative movement of the two to achieve three-dimensional spatial alignment and axial separation and approach; the end face imaging module comprises an integrated double-bevel prism and a camera; the integrated double-bevel prism is integrally formed, and the first and second reflection surfaces thereof form a fixed spatial included angle; the integrated double-bevel prism is configured to be movable to between the end faces of the left and right optical fibers when the two are axially separated, so that the first reflection surface faces the end face of the left optical fiber and the second reflection surface faces the end face of the right optical fiber; the camera is used to receive cat-eye images of the end faces of the left and right optical fibers turned by the first and second reflection surfaces; the input end of the control module is communicatively connected to the output end of the camera to receive the cat-eye images; and the output end of the control module is communicatively connected to the control end of the fiber clamping driving mechanism to output control signals for polarization axis alignment to the fiber clamping driving mechanism.

2. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 1, characterized in that: The end face imaging module further comprises a motor sliding table module, and the integrated double-bevel prism is fixedly installed on the motor sliding table module; the motor sliding table module is used to drive the integrated double-bevel prism to move in a direction perpendicular to the axial direction of the optical fiber, so as to realize movement of the integrated double-bevel prism to between the end faces of the left and right optical fibers and movement of the integrated double-bevel prism out of the end faces of the left and right optical fibers.

3. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 1, characterized in that: The laser heat source module comprises a CO2 laser and a beam guiding assembly; the beam guiding assembly divides the laser beam generated by the CO2 laser into two beams and focuses the two beams on the fusion points of the optical fibers in a symmetric distribution manner; the included angle between the two laser beams is greater than 170° and less than 180°.

4. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 1, characterized in that: The fiber clamping driving mechanism comprises: a right fiber clamping unit for clamping and driving the right optical fiber, which comprises a right rotating motor module and a right motor XYZ motor module group for driving the module to perform three-dimensional translation; a left fiber clamping unit for clamping and driving the left optical fiber, which comprises a left fiber clamp module and a left XYZ motor module group for driving the module to perform three-dimensional translation; At least one of the right fiber clamping unit and the left fiber clamping unit is integrated with a rotating motor capable of driving the optical fiber to rotate around its own axis.

5. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 3, characterized in that: The side face imaging module comprises a first side face camera and a second side face camera; the first side face camera and the second side face camera are respectively arranged on two sides of the fusion area in different directions to image the side faces of the optical fibers; The first side face camera is configured to be used as the camera in the end face imaging module to receive the cat-eye images turned by the integrated double-bevel prism.

6. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 1, characterized in that: The fiber clamping driving mechanism is provided with replaceable clamps to adapt to different specifications of optical fibers with cladding diameters in the range of 125 μm to 400 μm.

7. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 1, characterized in that: The position adjustment accuracy of the fiber clamping driving mechanism is not less than 0.05 μm.

8. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 1, characterized in that: The overall shape of the fusion machine is not greater than 500 mm x 345 mm x 270 mm in length, width and height, and the weight is not more than 80 kg.

9. The compact polarization maintaining laser welding machine based on cat-eye pair-axis technique according to claim 5, characterized in that: The second side camera and the first side camera are arranged on two sides of the fusion area respectively, the first side camera and the second side camera are fixedly arranged on the camera fixing frame, the length direction of the CO2 laser is parallel to the length direction of the optical platform, and the CO2 laser is fixedly installed on the optical platform; the beam guiding assembly comprises a mirror group, a first mirror, a beam splitter and two second mirrors; the mirror group comprises two mirrors, which are used for receiving the laser beam emitted by the CO2 laser, reflecting the laser beam along opposite but parallel light paths, guiding the laser beam to the first mirror after changing the position of the laser beam in the first plane, and reflecting the laser beam received by the first mirror to the beam splitter through the perforation on the camera fixing frame; the beam splitter divides the incident laser beam into a transmitted light and a reflected light, and guides the two lights to the two second mirrors respectively; The two second mirrors reflect and focus the two received laser beams to the fusion area.

10. A method of fusing optical fibers, characterized by: The miniaturized polarization maintaining laser fusion machine based on the cat-eye on-axis technology according to any one of claims 1-9 is used, comprising the following steps: a) based on the image collected by the side imaging module, controlling the optical fiber clamping driving mechanism to make the left optical fiber and the right optical fiber realize initial alignment in three-dimensional space; b) controlling the optical fiber clamping driving mechanism to make the end faces of the left optical fiber and the right optical fiber which have completed initial alignment separate from each other in the axial direction; c) moving the integrated double-bevel prism between the end faces of the left optical fiber and the right optical fiber, and making the first reflecting surface opposite to the end face of the left optical fiber and the second reflecting surface opposite to the end face of the right optical fiber; d) receiving the cat-eye images of the end faces of the left optical fiber and the right optical fiber which are turned through the first reflecting surface and the second reflecting surface through the camera at the same time; e) according to the cat-eye images, driving the optical fiber clamping driving mechanism to adjust the rotation angle of at least one optical fiber to complete the alignment of the polarization axis of the polarization maintaining optical fiber; f) controlling the optical fiber clamping driving mechanism to make the two optical fibers which have completed the alignment of the polarization axis approach to each other in the axial direction; g) controlling the laser heat source module to emit laser towards the butt joint part of the two optical fibers.

Images