Visible light guided dual-wave infrared laser synchronization calibration and coupling system and method

Abstract

The application provides a dual-wave infrared laser synchronous calibration and coupling system and method, which comprises a first mid-infrared laser, a second mid-infrared laser, a semi-transparent half-mirror, a first mirror, a second mirror, a third mirror, a fourth mirror, a first diaphragm group, a second diaphragm group, a third diaphragm group, a first reflective collimator, a second reflective collimator, a first visible laser source, a second visible laser source, a first mid-infrared optical fiber, a second mid-infrared optical fiber, a first output end collimator, a second output end collimator, a standard device, a first detector and a second detector. The application innovatively converts the alignment problem of invisible light into the accurate adjustment of visible light, solves the technical problem of synchronous calibration and efficient coupling of the dual-laser system, has the characteristics of simple operation, high precision and low cost, and is particularly suitable for the synchronous measurement of multiple parameters of combustion fields, catalytic reaction flows and other thermal chemical reaction processes.

Description

Technical Field

[0001] This invention relates to the field of laser spectral diagnostics and precision optical measurement technology, specifically to a dual-wave infrared laser synchronous calibration and coupling system and method. Background Technology

[0002] Precise online diagnostics of thermochemical reaction flows (such as combustion processes and catalytic reactions) are crucial for understanding reaction mechanisms, optimizing system design, and controlling pollutant formation. Mid-infrared laser absorption spectroscopy, due to its high sensitivity, high resolution, and ability to directly measure various key molecules (such as H₂O, CO, CO₂, NOx, and CH₄), has become one of the most powerful diagnostic tools in this field. The development of mid-infrared semiconductor laser sources, such as quantum cascade lasers and interband cascade lasers, has further promoted their application in harsh and complex environments.

[0003] In practical experimental setups such as burners, engines, or reactors, high-precision synchronous measurement of multiple parameters (e.g., multi-component concentration ratios, temperature, etc.) is typically achieved using dual-laser or even multi-laser measurement schemes. These schemes, by acquiring multiple spectral signals simultaneously along the same measurement path, effectively reflect the true reaction state, providing a crucial data foundation for accurate inversion of physical parameters. However, the introduction of dual-laser systems also presents new technical challenges: on the one hand, the outputs of the two lasers need to be efficiently and stably coupled into the transmission fiber to ensure optical path consistency and transmission efficiency; on the other hand, the frequency stability of the two lasers needs to be simultaneously monitored and calibrated to guarantee the timeliness and comparability of the measurement data.

[0004] Currently, some research has been conducted on fiber optic coupling technology for mid-infrared lasers, such as the scheme disclosed in patent application number CN202320634819.8, which typically uses a lens-type fiber collimator combined with a multi-axis adjustment frame to achieve fiber optic coupling. However, such schemes are difficult to directly extend to the synchronous coupling requirements of dual-path lasers, especially when using reflective collimation systems, as they are extremely sensitive to optical path alignment, making the coaxial and coincident adjustment process of the two optical paths particularly complex and difficult.

[0005] In laser frequency calibration, traditional methods often rely on independent Fabry-Perot interferometers or wavelength meters to calibrate each laser individually. This approach not only increases system complexity and cost but also makes it difficult to ensure the synchronization of frequency measurements between the two lasers. This results in timing discrepancies between data from different channels when analyzing transient processes, severely impacting the accuracy of dynamic measurements. Existing multi-channel measurement schemes, limited by system architecture or signal processing methods, often cannot achieve complete synchronization control of the optical path and frequency while maintaining high spectral resolution, thus limiting their application potential in high-speed dynamic scenarios. Furthermore, the invisibility of mid-infrared lasers further exacerbates the difficulty of dual-optical-path alignment, making system setup and calibration cumbersome and time-consuming, failing to meet the requirements of rapid deployment and real-time calibration of diagnostic systems in complex experimental environments.

[0006] Therefore, there is an urgent need in this field to develop a new technical solution that can simultaneously solve the problem of synchronous coupling and calibration of dual-band mid-infrared lasers, so as to overcome the defects of existing technologies such as difficult debugging, asynchronous calibration, and complex systems, and meet the urgent needs of modern thermochemical reaction flow diagnosis for multi-parameter, high-precision, and real-time measurement. Summary of the Invention

[0007] To address the technical problems existing in the background art mentioned above, this invention proposes a dual-wavelength infrared laser synchronous calibration and coupling system and method, which solves the problem that it is difficult to achieve synchronous calibration, efficient coupling and accurate alignment of dual-band mid-infrared lasers in complex experimental environments, thereby realizing rapid and accurate deployment and real-time calibration of dual-laser diagnostic optical paths.

[0008] To solve the above-mentioned technical problems, the present invention provides a visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system, which includes a first mid-infrared laser, a second mid-infrared laser, a semi-transparent mirror, a first reflector, a second reflector, a third reflector, a fourth reflector, a first aperture group, a second aperture group, a third aperture group, a first reflective collimator, a second reflective collimator, a first visible laser source, a second visible laser source, a first mid-infrared fiber, a second mid-infrared fiber, a first output collimator, a second output collimator, an etalon, a first detector, and a second detector;

[0009] The first and second mid-infrared lasers output mid-infrared lasers of different wavelengths; the first aperture group is disposed in the output optical path of the first mid-infrared laser; the second aperture group is disposed in the output optical path of the second mid-infrared laser; the first reflector is disposed in the output optical path of the first aperture group; the second reflector is disposed in the output optical path of the second aperture group; the third reflector is disposed in the reflected optical path of the first reflector; the fourth reflector is disposed in the reflected optical path of the second reflector; a semi-transparent mirror is matched and disposed at the intersection of the reflected light of the third and fourth reflectors to ensure that light emitted from the first reflective collimator is reflected by the semi-transparent mirror and then directed to the third reflector, and light emitted from the second reflective collimator is transmitted through the semi-transparent mirror and then directed to the third reflector; and to ensure that light emitted from the first reflective collimator is transmitted through the semi-transparent mirror and then directed to the fourth reflector, and light emitted from the second reflective collimator is reflected by the semi-transparent mirror and then directed to the fourth reflector.

[0010] The first reflective collimator is connected to the first visible laser source or the first output collimator via the first mid-infrared optical fiber to form a signal optical path;

[0011] The second reflective collimator is connected to the second visible laser source or the second output collimator via the second mid-infrared optical fiber to form a visible guiding optical path or a calibration transmission optical path.

[0012] The semi-transparent and semi-reflective mirror is disposed in the optical path to split and combine the light beams from the first reflective collimator and the second reflective collimator.

[0013] The first aperture group is disposed between the first mid-infrared laser and the first reflector, and the second aperture group is disposed between the second mid-infrared laser and the second reflector, for initial optical axis calibration;

[0014] The third aperture group is disposed between the second reflective collimator and the semi-transparent mirror, and is used to establish the optical axis of the calibration optical path during synchronous calibration.

[0015] The first output collimator is used to output the coupled signal optical path to the detector; the second output collimator is used to output the coupled calibration optical path to the detector.

[0016] During synchronous calibration, the etalon is placed between the semi-transparent mirror and the third aperture group, and the second detector is placed behind the etalon to receive the interference signal; during coupling and calibration effect verification, the etalon is placed in the calibration transmission optical path of the semi-transparent mirror, and the second detector is placed behind the etalon to receive the interference signal.

[0017] The first detector is located at the output end of the signal optical path, and the second detector is located at the output end of the calibration transmission optical path, for receiving and detecting optical signals.

[0018] As a preferred embodiment of the present invention: the first visible laser source and the second visible laser source are both semiconductor laser pointers with a wavelength of 650nm and an output power of 1-100mW; the free spectral range of the etalon is adapted to the wavelength interval of the first mid-infrared laser and the second mid-infrared laser.

[0019] As a preferred embodiment of the present invention: the first reflector, the second reflector, the third reflector and the fourth reflector are all mounted on a three-dimensional adjustment frame, and all are high reflectors with a gold film, silver film, aluminum film, dielectric film or metal-dielectric composite film coated on the surface.

[0020] As a preferred embodiment of the present invention: the first aperture group, the second aperture group, and the third aperture group each include two apertures spaced apart along the optical path, the aperture of each aperture is 1-5mm, and the aperture range of each aperture is adapted to the output diameter of the first reflective collimator and the second reflective collimator and the beam diameter of the first mid-infrared laser and the second mid-infrared laser, so as to ensure that the beam passes through effectively; the spacing between adjacent apertures is 10-50cm.

[0021] As a preferred embodiment of the present invention, both the first reflective collimator and the second reflective collimator use fiber-coupled 90° off-axis parabolic mirrors.

[0022] As a preferred embodiment of the present invention: the first mid-infrared optical fiber and the second mid-infrared optical fiber are any one of fluoride glass optical fiber, chalcogenide glass optical fiber or hollow optical fiber, with a core diameter of 10-500 μm and a numerical aperture of 0.05-0.4.

[0023] A visible light-guided dual-wavelength infrared laser synchronous calibration and coupling method, based on the aforementioned visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system, includes the following steps:

[0024] S1, Initial optical axis calibration

[0025] Turn on the first and second mid-infrared lasers respectively. Using an infrared observation card, adjust the first reflector corresponding to the first mid-infrared laser to ensure the mid-infrared laser spot is stably located in the effective reflection center region of the first reflector. Then, adjust the position of the first aperture group to ensure the mid-infrared laser beam output from the first mid-infrared laser passes precisely through the center of each aperture in the first aperture group. With the mid-infrared laser beam output from the first mid-infrared laser already collimated by its built-in collimating lens, repeatedly fine-tune the relative positions of the first reflector and the first aperture group to make the laser beam precisely coaxial with the mechanical axis defined by the center of the aperture in the first aperture group. When this condition is met... Under these conditions, an initial optical axis reference from the first mid-infrared laser to the first reflector is successfully established. Similarly, the second reflector corresponding to the second mid-infrared laser is adjusted to ensure that the mid-infrared laser spot is stably located in the effective reflection center region of the second reflector. Then, the position of the second aperture group is adjusted to ensure that the mid-infrared laser beam of the second mid-infrared laser passes precisely through the center of the aperture of each aperture in the second aperture group in sequence. By repeatedly fine-tuning the relative position of the second reflector and the second aperture group, the laser beam is made precisely coaxial with the mechanical axis defined by the center of the aperture of the second aperture group. When this condition is met, an initial optical axis reference from the second mid-infrared laser to the second reflector is successfully established.

[0026] S2. Establishment of visible light-guided optical path

[0027] S2.1 Visible Light Path Arrangement: Turn off the first and second mid-infrared lasers and place temporary shielding plates in front of their output ports; on the optical platform, arrange the first reflective collimator, the second reflective collimator, and the semi-transparent mirror in a right-angled triangle, with the semi-transparent mirror located at the right-angle vertex, and the first and second reflective collimators located at the other two vertices respectively; connect the first visible laser source to the first reflective collimator through the first mid-infrared fiber and turn it on; connect the second visible laser source to the second reflective collimator through the second mid-infrared fiber and turn it on; at this time, the visible light beam output from the first reflective collimator is directed towards the semi-transparent mirror, and the visible light beam output from the second reflective collimator is also directed towards the semi-transparent mirror;

[0028] S2.2, Adjustment of the semi-transparent mirror and beam combining: A third and fourth reflecting mirror are placed behind the semi-transparent mirror, so that light emitted from the first reflecting collimator is reflected by the semi-transparent mirror and then directed to the third reflecting mirror, and light emitted from the second reflecting collimator is transmitted through the semi-transparent mirror and also directed to the third reflecting mirror; simultaneously, light emitted from the first reflecting collimator is transmitted through the semi-transparent mirror and then directed to the fourth reflecting mirror, and light emitted from the second reflecting collimator is reflected by the semi-transparent mirror and also directed to the fourth reflecting mirror; the pitch and deflection angles of the semi-transparent mirror are finely adjusted so that the reflected light spot from the first reflecting collimator and the transmitted light spot from the second reflecting collimator are precisely aligned on the third reflecting mirror; based on the symmetrical optical characteristics of the semi-transparent mirror, when the light spots are aligned on the third reflecting mirror, the transmitted light spot from the first reflecting collimator and the reflected light spot from the second reflecting collimator will also automatically align on the fourth reflecting mirror, thus simultaneously completing the beam combining and splitting of the two optical paths;

[0029] S2.3. Guided Visible Light to the Initial Optical Axis Reference: Keeping the position of the semi-transparent mirror unchanged, adjust the third mirror so that the combined visible light beam reaching the third mirror is guided to the first mirror in the initial optical axis calibration; adjust the fourth mirror so that the combined visible light beam reaching the fourth mirror is guided to the second mirror in the initial optical axis calibration; by fine-tuning the third and fourth mirrors, the visible light beam passes through the center of the apertures of the first and second aperture groups in sequence, and finally reaches the output ports of the first and second mid-infrared lasers; when the visible light beam precisely passes through the center of the apertures of the first and second aperture groups and reaches the output ports of the first and second mid-infrared lasers, it indicates that the visible light path has coincided with the initial optical axis reference;

[0030] S3, Mid-infrared laser coupling

[0031] Disconnect the first and second visible laser sources. Connect the first reflective collimator to the first output collimator via the first mid-infrared fiber, and align the output of the first output collimator with the first detector. Connect the second reflective collimator to the second output collimator via the second mid-infrared fiber, and align the output of the second output collimator with the second detector. After removing the temporary shield, turn on the first and second mid-infrared lasers. By coordinating and fine-tuning the spatial positions of the third and fourth reflectors, ensure that the mid-infrared lasers output by the first and second mid-infrared lasers precisely coincide with the calibrated visible light path, thereby achieving stable optical signal reception on the first and second detectors and completing the coupling of the dual-band lasers.

[0032] S4, Synchronous Calibration

[0033] S4.1 Visible Light Guided Erection: Disconnect the second output collimator from the second mid-infrared fiber, and remove the second output collimator and the second detector from the optical path; connect the second visible laser source to the second reflective collimator through the second mid-infrared fiber and turn it on; adjust the third aperture group set between the second reflective collimator and the semi-transparent mirror to ensure that the visible light spot output from the second reflective collimator passes precisely through the center of the aperture of each aperture in the third aperture group in sequence, so as to establish the coaxiality of the optical axis; then, place the etalon between the third aperture group and the semi-transparent mirror, and adjust the position and tilt angle of the etalon so that the visible light spot reflected back from the surface of the etalon passes through the center of the third aperture group in the opposite direction, indicating that the etalon has achieved normal incident alignment;

[0034] S4.2 Mid-infrared laser synchronous calibration: Keep the position of the etalon unchanged, place the second detector behind the etalon, turn on the two first mid-infrared lasers and the second mid-infrared laser, and collect the interference signal generated by the etalon through the second detector; by analyzing the frequency characteristics of the interference signal, the synchronous frequency calibration of the dual-band laser is achieved.

[0035] S5. Coupling and Calibration Effect Verification Steps

[0036] The output signals of the first and second detectors are synchronously connected to an oscilloscope. The output of the signal optical path is acquired through the first detector, and the interference signal generated by the etalon is acquired through the second detector. The coupling efficiency is verified by observing the stability of the signal strength of the first detector, and the synchronous calibration effect is verified by observing the stability of the interference signal of the second detector.

[0037] As a preferred embodiment of the present invention: in step S2, the light spots from the first reflective collimator and the second reflective collimator are made to coincide on the third reflective mirror by finely adjusting the semi-transparent and semi-reflective mirror. Based on the symmetrical optical characteristics of the semi-transparent and semi-reflective mirror, the light spots on the fourth reflective mirror (6) are simultaneously made to coincide.

[0038] As a preferred embodiment of the present invention: in steps S2 and S3, a temporary shielding plate is placed in front of the light output ports of the first mid-infrared laser and the second mid-infrared laser to effectively protect the laser output ports from direct damage by strong visible light during visible light guidance and debugging.

[0039] As a preferred embodiment of the present invention: the synchronous frequency calibration in step S4.2 is achieved by analyzing the interference signal received by the second detector in real time, extracting the periodicity and phase information of the interference signal, and combining it with the free spectral range parameters of the etalon to realize the synchronous monitoring and stability evaluation of the output frequencies of the first mid-infrared laser and the second mid-infrared laser.

[0040] As a preferred embodiment of the present invention: in step S5, the output signals of the first detector and the second detector are connected to the oscilloscope through a synchronous triggering method, and are synchronously displayed and compared in the time domain, thereby ensuring the consistency of the acquisition time of the dual-band laser signals and providing a reliable timing reference for subsequent data processing.

[0041] By adopting the above technical solution, the present invention has the following beneficial effects:

[0042] This invention addresses the technical challenge of achieving synchronous calibration and efficient coupling of dual-band mid-infrared laser systems in complex experimental environments. It provides a synchronous calibration solution based on visible light reverse guidance, which is particularly suitable for precisely coupling two mid-infrared laser sources, such as quantum cascade lasers of different wavelengths, to a transmission optical fiber. By integrating a standard, it enables real-time synchronous monitoring and calibration of the dual laser frequencies. This solution can be widely applied to high-precision absorption spectroscopy measurements of multi-component concentrations / temperatures in thermochemical reaction processes such as combustion fields and catalytic reaction flows.

[0043] (1) This invention innovatively proposes an integrated solution for synchronous calibration and coupling of visible light-guided dual-wave infrared lasers, which transforms the alignment problem of invisible light into the precise adjustment of visible light, fundamentally solving the technical problem of synchronous calibration of dual laser systems;

[0044] (2) By using visible light guidance, the symmetrical optical properties of the semi-transparent and semi-reflective mirror are used to simultaneously complete the beam combining and splitting of the two optical paths, which greatly simplifies the debugging process and reduces the requirements for professional equipment and operating experience.

[0045] (3) The calibration optical path design of the integrated etalon, combined with the innovative aperture group alignment method, realizes real-time synchronous monitoring and calibration of dual laser frequencies, ensuring the accuracy and reliability of measurement data;

[0046] (4) The system adopts a phased implementation strategy of first establishing a visible light path reference and then performing mid-infrared laser coupling and calibration. The system construction process is clear, the engineering practicality is strong, no expensive infrared observation equipment is required, the cost is low, the operation is simple and the reliability is high, and it is especially suitable for rapid deployment in complex experimental environments.

[0047] (5) The present invention adopts a phased implementation strategy, which can complete most of the optical path calibration work through visible light in non-experimental state. This enables the system to be quickly deployed and accurately reset when facing harsh environments, limited space and strong background radiation such as combustion chambers and engine test benches, effectively avoiding the limitation of mid-infrared detectors being difficult to align optical axes under strong background noise.

[0048] (6) By introducing temporary shielding plates and visible light-guided debugging steps, damage to the fiber end face or laser output port caused by alignment errors of infrared laser during the high-power debugging stage is avoided. This significantly improves the safety of core precision optical components while ensuring debugging efficiency. Attached Figure Description

[0049] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0050] Figure 1 This is a schematic diagram of the system optical path during the visible light guiding optical path establishment step in an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of the system optical path during the mid-infrared laser coupling step in an embodiment of the present invention;

[0052] Figure 3 This is a schematic diagram of the system optical path during the synchronization calibration step in an embodiment of the present invention;

[0053] Figure 4 This is a schematic diagram of the system optical path during the verification of coupling and calibration effects in an embodiment of the present invention. Detailed Implementation

[0054] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0055] The present invention will be further explained below with reference to specific embodiments.

[0056] like Figure 1-4As shown in the figure, this embodiment provides a visible light-guided dual-wave infrared laser synchronous calibration and coupling system for combustion diagnosis, including a first mid-infrared laser 1, a second mid-infrared laser 2, a first reflector 3, a second reflector 4, a third reflector 5, a fourth reflector 6, a semi-transparent mirror 7, a first aperture group 8, a second aperture group 9, a third aperture group 10, a first reflective collimator 11, a second reflective collimator 12, a first visible laser source 13, a second visible laser source 14, a first mid-infrared optical fiber 15, a second mid-infrared optical fiber 16, a first output collimator 17, a second output collimator 18, an etalon 19, a first detector 20, and a second detector 21.

[0057] The first mid-infrared laser 1 and the second mid-infrared laser 2 output mid-infrared lasers of different wavelengths; the first aperture group 8 is disposed in the output optical path of the first mid-infrared laser 1; the second aperture group 9 is disposed in the output optical path of the second mid-infrared laser 2; the first reflector 3 is disposed in the output optical path of the first aperture group 8; the second reflector 4 is disposed in the output optical path of the second aperture group 9; the third reflector 5 is disposed in the reflected optical path of the first reflector 3; the fourth reflector 6 is disposed in the reflected optical path of the second reflector 4; the semi-transparent half-transparent laser... The mirror 7 is matched and positioned at the intersection of the reflected light from the third mirror 5 and the fourth mirror 6 to ensure that the light emitted from the first reflective collimator 11 is reflected by the semi-transparent mirror 7 and then directed to the third mirror 5, and the light emitted from the second reflective collimator 12 is transmitted through the semi-transparent mirror 7 and then directed to the third mirror 5; and to ensure that the light emitted from the first reflective collimator 11 is transmitted through the semi-transparent mirror 7 and then directed to the fourth mirror 6, and the light emitted from the second reflective collimator 12 is reflected by the semi-transparent mirror 7 and then directed to the fourth mirror 6.

[0058] The first reflective collimator 11 is connected to the first visible laser source 13 or the first output collimator 17 via the first mid-infrared optical fiber 15, forming a signal optical path.

[0059] The second reflective collimator 12 can be selectively connected to the second visible laser source 14 or the second output collimator 18 via the second mid-infrared optical fiber 16 to form a visible guiding optical path or a calibration transmission optical path.

[0060] The semi-transparent and semi-reflective mirror 7 is disposed in the optical path to split and combine the light beams from the first reflective collimator 11 and the second reflective collimator 12.

[0061] The first aperture group 8 is disposed between the first mid-infrared laser 1 and the first reflector 3, and the second aperture group 9 is disposed between the second mid-infrared laser 2 and the second reflector 4, for initial optical axis calibration.

[0062] The third aperture group 10 is located between the second reflective collimator 12 and the semi-transparent mirror 7, and is used to establish the optical axis of the calibration optical path during synchronous calibration.

[0063] The first output collimator 17 is used to output the coupled signal optical path to the detector; the second output collimator 18 is used to output the coupled calibration optical path to the detector.

[0064] When performing synchronous calibration, the etalon 19 is placed between the semi-transparent mirror 7 and the third aperture group 10, and the second detector 21 is placed behind the etalon 19 to receive the interference signal; when verifying the coupling and calibration effect, the etalon 19 is placed on the calibration transmission optical path of the semi-transparent mirror 7, and the second detector 21 is placed behind the etalon 19 to receive the interference signal.

[0065] The first detector 20 is located at the output end of the signal optical path, and the second detector 21 is located at the output end of the calibration transmission optical path, for receiving and detecting optical signals.

[0066] The first aperture group 8, the second aperture group 9, and the third aperture group 10 each include two apertures spaced apart along the optical path. The aperture of each aperture is 1-5mm. The aperture range of each aperture is adapted to the light output diameter of the first reflective collimator 11 and the second reflective collimator 12, as well as the beam diameter of the first mid-infrared laser 1 and the second mid-infrared laser 2, to ensure effective beam passage. The spacing between adjacent apertures is 10-50cm.

[0067] The first mid-infrared fiber 15 and the second mid-infrared fiber 16 are any one of fluoride glass fiber, chalcogenide glass fiber or hollow fiber, with a core diameter of 10-500 μm and a numerical aperture of 0.05-0.4.

[0068] In this embodiment, the first mid-infrared laser 1 and the second mid-infrared laser 2 are both quantum cascade lasers with output wavelengths of 4.6μm and 4.8μm, respectively; the first reflecting mirror 3, the second reflecting mirror 4, the third reflecting mirror 5, and the fourth reflecting mirror 6 are all high-reflectivity mirrors coated with a protective gold film; the first reflecting mirror 3, the second reflecting mirror 4, the third reflecting mirror 5, and the fourth reflecting mirror 6 are all mounted on a three-dimensional precision adjustment frame, and are all high-reflectivity mirrors with gold, silver, aluminum, dielectric, or metal-dielectric composite films coated on their surfaces; the semi-transparent and semi-reflective mirror 7 is a broadband beam splitter with a 50 / 50 splitting ratio in the 4-5μm band; the first aperture group 8, the second aperture group 9, and the third aperture group 10 each include two apertures with an aperture of 2mm, and the distance between adjacent apertures is 30cm; the first reflective collimator 11 and the second reflective collimator 12 are also mentioned. Collimators 12 each include a 90° off-axis parabolic mirror with a focal length of 33mm and a light-transmitting aperture of 16.5mm; the first mid-infrared fiber 15 and the second mid-infrared fiber 16 are fluoride glass fibers with a length of 2m, a core diameter of 100μm, and a numerical aperture of 0.20; the first visible laser source 13 and the second visible laser source 14 are semiconductor laser pointers with a wavelength of 650nm and an output power of 1-100mW; the first output collimator 17 and the second output collimator 18 are lens collimators; the free spectral range of the etalon 19 is adapted to the wavelength interval of the first mid-infrared laser 1 and the second mid-infrared laser 2; the free spectral range of the etalon 19 is 50GHz; the first detector 20 and the second detector 21 are thermoelectric cooled MCT detectors with a response band of 3-5μm.

[0069] The implementation process of laser coupling and calibration using the visible light-guided dual-wave infrared laser synchronous calibration and coupling system of this embodiment is as follows:

[0070] S1, Initial optical axis calibration

[0071] Turn on the first mid-infrared laser 1, monitor it with an infrared observation card, and adjust the first reflector 3 corresponding to the first mid-infrared laser 1 to ensure that the mid-infrared laser spot is stably located in the effective reflection center area of ​​the first reflector 3. Then adjust the position of the first aperture group 8 to ensure that the mid-infrared laser beam output by the first mid-infrared laser 1 passes through the center of the aperture of each aperture of the first aperture group 8 in sequence. Under the premise that the mid-infrared laser beam output by the first mid-infrared laser 1 has been collimated by its own collimating lens, by repeatedly fine-tuning the relative position of the first reflector 3 and the first aperture group 8, the laser beam is made to be precisely coaxial with the mechanical axis defined by the center of the aperture of the first aperture group 8. When this condition is met, the initial optical axis reference from the first mid-infrared laser 1 to the first reflector 3 is successfully established.

[0072] Using the same method, the second mid-infrared laser 2 is turned on and adjusted to ensure that its mid-infrared laser spot is stably located in the effective reflection center region of the second reflector 4. Then, the position of the second aperture group 9 is adjusted to ensure that the mid-infrared laser beam from the second mid-infrared laser 2 passes precisely through the center of each aperture in the second aperture group 9. By repeatedly fine-tuning the relative position of the second reflector 4 and the second aperture group 9, the laser beam is precisely coaxial with the mechanical axis defined by the center of the aperture in the second aperture group 9. When this condition is met, the initial optical axis reference from the second mid-infrared laser 2 to the second reflector 4 is successfully established. After completion, both mid-infrared lasers are turned off, and temporary shielding plates are installed in front of their output ports.

[0073] S2. Establishment of visible light-guided optical path

[0074] S2.1 Visible Light Path Arrangement: Turn off the first mid-infrared laser 1 and the second mid-infrared laser 2, and place temporary shielding plates in front of their output ports. On the optical platform, arrange the first reflective collimator 11, the second reflective collimator 12, and the semi-transparent mirror 7 into a right-angled triangle, with the semi-transparent mirror 7 located at the right-angle vertex, and the first reflective collimator 11 and the second reflective collimator 12 located at the other two vertices. Connect the first visible laser source 13 to the first reflective collimator 11 via the first mid-infrared fiber 15 and turn it on; connect the second visible laser source 14 to the second reflective collimator 12 via the second mid-infrared fiber 16 and turn it on. At this time, the visible light beam output from the first reflective collimator 11 is directed towards the semi-transparent mirror 7, and the visible light beam output from the second reflective collimator 12 is also directed towards the semi-transparent mirror 7.

[0075] S2.2, Adjustment of the semi-transparent and semi-reflective mirror and beam combining: A third reflecting mirror 5 and a fourth reflecting mirror 6 are placed behind the semi-transparent and semi-reflective mirror 7 so that the light emitted from the first reflecting collimator 11 is reflected by the semi-transparent and semi-reflective mirror 7 and then directed to the third reflecting mirror 5, and the light emitted from the second reflecting collimator 12 is transmitted through the semi-transparent and semi-reflective mirror 7 and then directed to the third reflecting mirror 5; at the same time, the light emitted from the first reflecting collimator 11 is transmitted through the semi-transparent and semi-reflective mirror 7 and then directed to the fourth reflecting mirror 6, and the light emitted from the second reflecting collimator 12 is reflected by the semi-transparent and semi-reflective mirror 7 and then directed to the fourth reflecting mirror 6. By finely adjusting the pitch and deflection angles of the semi-transparent mirror 7, the reflected light spot from the first reflective collimator 11 and the transmitted light spot from the second reflective collimator 12 on the third reflective mirror 5 are precisely aligned. Based on the symmetrical optical characteristics of the semi-transparent mirror 7, when the light spots are aligned on the third reflective mirror 5, the transmitted light spot from the first reflective collimator 11 and the reflected light spot from the second reflective collimator 12 on the fourth reflective mirror 6 will also automatically align, thereby synchronously completing the beam combining and splitting of the two optical paths.

[0076] S2.3. Guided Visible Light to the Initial Optical Axis Reference: Keeping the position of the semi-transparent mirror 7 unchanged, adjust the third mirror 5 so that the combined visible light beam reaching the third mirror 5 is guided to the first mirror 3 in the initial optical axis calibration; adjust the fourth mirror 6 so that the combined visible light beam reaching the fourth mirror 6 is guided to the second mirror 4 in the initial optical axis calibration. By fine-tuning the third mirror 5 and the fourth mirror 6, the visible light beam passes sequentially through the center of the apertures of the first aperture group 8 and the second aperture group 9, and finally reaches the output ports of the first mid-infrared laser 1 and the second mid-infrared laser 2. When the visible light beam precisely passes through the center of the apertures of the first aperture group 8 and the second aperture group 9 and reaches the output ports of the first mid-infrared laser 1 and the second mid-infrared laser 2, it indicates that the visible light path has coincided with the initial optical axis reference.

[0077] S3, Mid-infrared laser coupling

[0078] Disconnect the first visible laser source 13 and the second visible laser source 14. Connect the first reflective collimator 11 to the first output collimator 17 via the first mid-infrared fiber 15, and align the output end of the first output collimator 17 with the first detector 20. Connect the second reflective collimator 12 to the second output collimator 18 via the second mid-infrared fiber 16, and align the output end of the second output collimator 18 with the second detector 21. Place a temporary shield in front of the output ports of the first mid-infrared laser 1 and the second mid-infrared laser 2 to effectively protect the laser output ports from direct damage by strong visible light during visible light guidance and debugging. After removing the temporary shield, turn on the first mid-infrared laser 1 and the second mid-infrared laser 2. By coordinating and fine-tuning the spatial positions of the third reflector 5 and the fourth reflector 6, ensure that the mid-infrared laser output by the first mid-infrared laser 1 and the second mid-infrared laser 2 precisely coincides with the calibrated visible light path, thereby achieving stable optical signal reception on the first detector 20 and the second detector 21, and completing the coupling of the dual-band laser.

[0079] S4, Synchronous Calibration

[0080] S4.1 Visible Light Guided Erection: Disconnect the second output collimator 18 from the second mid-infrared fiber 16, and remove the second output collimator 18 and the second detector 21 from the optical path. Connect the second visible laser source 14 to the second reflective collimator 12 via the second mid-infrared fiber 16 and turn it on. Adjust the third aperture group 10 located between the second reflective collimator 12 and the semi-transparent mirror 7 to ensure that the visible light spot output from the second reflective collimator 12 passes precisely through the center of the aperture of each aperture in the third aperture group 10 in sequence, thus establishing the coaxiality of the optical axis. Subsequently, place the etalon 19 between the third aperture group 10 and the semi-transparent mirror 7, and adjust the position and tilt angle of the etalon 19 so that the visible light spot reflected back from the surface of the etalon 19 passes through the center of the third aperture group 10 in the opposite direction, indicating that the etalon 19 has achieved normal incident alignment.

[0081] S4.2 Mid-infrared laser synchronous calibration: Keep the position of the etalon 19 unchanged, and place the second detector 21 behind the etalon 19. Turn on the two first mid-infrared lasers 1 and the second mid-infrared laser 2, and collect the interference signal generated by the etalon 19 through the second detector 21. By analyzing the frequency characteristics of the interference signal, the synchronous frequency calibration of the dual-band laser is achieved.

[0082] The synchronous frequency calibration in step S4.2 above is achieved by analyzing the interference signal received by the second detector 21 in real time, extracting the periodicity and phase information of the interference signal, and combining it with the free spectral range parameters of the etalon to realize the synchronous monitoring and stability evaluation of the output frequencies of the first mid-infrared laser 1 and the second mid-infrared laser 2.

[0083] S5. Verification of Coupling and Calibration Effects

[0084] The output signals of the first detector 20 and the second detector 21 are synchronously connected to an oscilloscope. The output of the signal optical path is acquired through the first detector 20, and the interference signal generated by the etalon 19 is acquired through the second detector 21. The coupling efficiency is verified by observing the stability of the signal strength of the first detector 20, and the synchronous calibration effect is verified by observing the stability of the interference signal of the second detector 21.

[0085] In step S5 above, the output signals of the first detector 20 and the second detector 21 are connected to the oscilloscope through synchronous triggering, and are synchronously displayed and compared in the time domain, thereby ensuring the consistency of the acquisition time of the dual-band laser signals and providing a reliable timing reference for subsequent data processing.

[0086] In summary, this embodiment addresses the challenge of simultaneous calibration and efficient coupling in dual-band mid-infrared laser systems by innovatively employing a method combining visible light guidance and etalon calibration. Through a phased, five-step process, it achieves a system construction strategy that first establishes a visible light path reference before performing mid-infrared laser coupling and calibration. This method is intuitive, highly accurate, and reliable, providing an advanced laser transmission and calibration solution for thermochemical reaction flow diagnostics.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system, characterized in that: The calibration and coupling system includes a first mid-infrared laser (1), a second mid-infrared laser (2), a semi-transparent mirror (7), a first reflector (3), a second reflector (4), a third reflector (5), a fourth reflector (6), a first aperture group (8), a second aperture group (9), a third aperture group (10), a first reflective collimator (11), a second reflective collimator (12), a first visible laser source (13), a second visible laser source (14), a first mid-infrared fiber (15), a second mid-infrared fiber (16), a first output collimator (17), a second output collimator (18), an etalon (19), a first detector (20), and a second detector (21). The first mid-infrared laser (1) and the second mid-infrared laser (2) output mid-infrared lasers of different wavelengths; the first aperture group (8) is disposed on the output optical path of the first mid-infrared laser (1); the second aperture group (9) is disposed on the output optical path of the second mid-infrared laser (2); the first reflector (3) is disposed on the output optical path of the first aperture group (8); the second reflector (4) is disposed on the output optical path of the second aperture group (9); the third reflector (5) is disposed on the reflection optical path of the first reflector (3); the fourth reflector (6) is disposed on the reflection optical path of the second reflector (4); the semi-transparent and semi-reflective... The mirror (7) is matched and set at the intersection of the reflected light of the third mirror (5) and the fourth mirror (6) to ensure that the light emitted from the first reflective collimator (11) is reflected by the semi-transparent mirror (7) and then shines on the third mirror (5), and the light emitted from the second reflective collimator (12) is also transmitted through the semi-transparent mirror (7) and then shines on the third mirror (5); and to ensure that the light emitted from the first reflective collimator (11) is transmitted through the semi-transparent mirror (7) and then shines on the fourth mirror (6), and the light emitted from the second reflective collimator (12) is also reflected by the semi-transparent mirror (7) and then shines on the fourth mirror (6); The first reflective collimator (11) is connected to the first visible laser source (13) or the first output collimator (17) through the first mid-infrared optical fiber (15) to form a signal optical path; The second reflective collimator (12) is connected to the second visible laser source (14) or the second output collimator (18) through the second mid-infrared optical fiber (16) to form a visible guiding optical path or a calibration transmission optical path; The semi-transparent and semi-reflective mirror (7) is disposed in the optical path to split and combine the light beams from the first reflective collimator (11) and the second reflective collimator (12). The first aperture group (8) is disposed between the first mid-infrared laser (1) and the first reflector (3), and the second aperture group (9) is disposed between the second mid-infrared laser (2) and the second reflector (4) for initial optical axis calibration; The third aperture group (10) is located between the second reflective collimator (12) and the semi-transparent mirror (7) and is used to establish the optical axis of the calibration optical path in synchronous calibration. The first output collimator (17) is used to output the coupled signal optical path to the detector; The second output collimator (18) is used to output the coupled calibration optical path to the detector; When performing synchronous calibration, the etalon (19) is placed between the semi-transparent mirror (7) and the third aperture group (10), and the second detector (21) is placed behind the etalon (19) to receive the interference signal; when verifying the coupling and calibration effect, the etalon (19) is placed on the calibration transmission optical path of the semi-transparent mirror (7), and the second detector (21) is placed behind the etalon (19) to receive the interference signal; The first detector (20) is located at the output end of the signal optical path, and the second detector (21) is located at the output end of the calibration transmission optical path, for receiving and detecting optical signals.

2. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system according to claim 1, characterized in that: The first visible laser source (13) and the second visible laser source (14) are both semiconductor laser pointers with a wavelength of 650nm and an output power of 1-100mW; The free spectral range of the etalon (19) is adapted to the wavelength interval of the first mid-infrared laser (1) and the second mid-infrared laser (2).

3. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system according to claim 1, characterized in that: The first reflector (3), the second reflector (4), the third reflector (5) and the fourth reflector (6) are all mounted on a three-dimensional adjustment frame, and are all high reflectors with gold film, silver film, aluminum film, dielectric film or metal-dielectric composite film coated on the surface.

4. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system according to claim 1, characterized in that: The first aperture group (8), the second aperture group (9) and the third aperture group (10) each include two apertures spaced apart along the optical path. The aperture of each aperture is 1-5mm. The aperture range of each aperture is adapted to the light output diameter of the first reflective collimator (11) and the second reflective collimator (12) and the beam diameter of the first mid-infrared laser (1) and the second mid-infrared laser (2) to ensure that the beam passes through effectively. The spacing between adjacent apertures is 10-50cm.

5. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system according to claim 1, characterized in that: Both the first reflective collimator (11) and the second reflective collimator (12) use fiber-coupled 90° off-axis parabolic mirrors.

6. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system according to claim 1, characterized in that: The first mid-infrared fiber (15) and the second mid-infrared fiber (16) are either fluoride glass fiber, chalcogenide glass fiber or hollow fiber, with a core diameter of 10-500 μm and a numerical aperture of 0.05-0.

4.

7. A visible light-guided dual-wavelength infrared laser synchronous calibration and coupling method, based on the visible light-guided dual-wavelength infrared laser synchronous calibration and coupling system according to any one of claims 1-6, characterized in that, Includes the following steps: S1, Initial optical axis calibration Turn on the first mid-infrared laser (1) and the second mid-infrared laser (2) respectively. Monitor with an infrared observation card and adjust the first reflector (3) corresponding to the first mid-infrared laser (1) to ensure that the mid-infrared laser spot is stably located in the effective reflection center area of ​​the first reflector (3). Then adjust the position of the first aperture group (8) to ensure that the mid-infrared laser beam output by the first mid-infrared laser (1) passes through the center of the aperture of each aperture of the first aperture group (8) in sequence. Under the premise that the mid-infrared laser beam output by the first mid-infrared laser (1) has been collimated by its own collimating lens, by repeatedly fine-tuning the relative position of the first reflector (3) and the first aperture group (8), make the laser beam precisely coaxial with the mechanical axis defined by the center of the aperture group (8). When this condition is met... When the conditions are met, the initial optical axis reference from the first mid-infrared laser (1) to the first reflector (3) is successfully established; similarly, the second reflector (4) corresponding to the second mid-infrared laser (2) is adjusted to ensure that the mid-infrared laser spot is stably located in the effective reflection center area of ​​the second reflector (4); then the position of the second aperture group (9) is adjusted to ensure that the mid-infrared laser beam of the second mid-infrared laser (2) passes through the center of the aperture of each aperture of the second aperture group (9) in sequence; by repeatedly fine-tuning the relative position of the second reflector (4) and the second aperture group (9), the laser beam is precisely coaxial with the mechanical axis defined by the center of the aperture of the second aperture group (9); when this condition is met, the initial optical axis reference from the second mid-infrared laser (2) to the second reflector (4) is successfully established. S2. Establishment of visible light-guided optical path S2.1 Visible light path arrangement: Turn off the first mid-infrared laser (1) and the second mid-infrared laser (2) and place a temporary shield in front of their output ports; on the optical platform, arrange the first reflective collimator (11), the second reflective collimator (12) and the semi-transparent mirror (7) into a right triangle, with the semi-transparent mirror (7) located at the right angle vertex, and the first reflective collimator (11) and the second reflective collimator (12) located at the other two vertices respectively; connect the first visible laser source (13) to the first reflective collimator (11) through the first mid-infrared fiber (15) and turn it on; connect the second visible laser source (14) to the second reflective collimator (12) through the second mid-infrared fiber (16) and turn it on; at this time, the visible light beam output from the first reflective collimator (11) is directed toward the semi-transparent mirror (7), and the visible light beam output from the second reflective collimator (12) is also directed toward the semi-transparent mirror (7); S2.2, Adjustment of the semi-transparent mirror (7) and beam combining: Place the third mirror (5) and the fourth mirror (6) behind the semi-transparent mirror (7), so that the light emitted from the first reflective collimator (11) is reflected by the semi-transparent mirror (7) and then shines on the third mirror (5), and the light emitted from the second reflective collimator (12) is transmitted through the semi-transparent mirror (7) and also shines on the third mirror (5); at the same time, the light emitted from the first reflective collimator (11) is transmitted through the semi-transparent mirror (7) and then shines on the fourth mirror (6), and the light emitted from the second reflective collimator (12) is transmitted through the semi-transparent mirror (7) and then shines on the fourth mirror (6), and the light emitted from the second reflective collimator (12) is transmitted through the semi-transparent mirror (7) and then shines on the fourth mirror (6), and the light emitted from the second reflective collimator (12) is transmitted through the semi-transparent mirror (7) and then shines on the third mirror (6). After reflection, the light also shines on the fourth reflecting mirror (6); the pitch and deflection angles of the semi-transparent and semi-reflective mirror (7) are finely adjusted so that the reflected light spot from the first reflecting collimator (11) and the transmitted light spot from the second reflecting collimator (12) on the third reflecting mirror (5) are precisely aligned; based on the symmetrical optical characteristics of the semi-transparent and semi-reflective mirror (7), when the light spots are aligned on the third reflecting mirror (5), the transmitted light spot from the first reflecting collimator (11) and the reflected light spot from the second reflecting collimator (12) on the fourth reflecting mirror (6) will also automatically align, thereby simultaneously completing the beam combining and splitting of the two optical paths; S2.

3. Guide the visible light to the initial optical axis reference: Keep the position of the semi-transparent mirror (7) unchanged, adjust the third mirror (5) so that the combined visible light reaching the third mirror (5) is guided to the first mirror (3) in the initial optical axis calibration; adjust the fourth mirror (6) so that the combined visible light reaching the fourth mirror (6) is guided to the second mirror (4) in the initial optical axis calibration; by finely adjusting the third mirror (5) and the fourth mirror (6), the visible light beam passes through the center of the holes of the first aperture group (8) and the second aperture group (9) in sequence, and finally reaches the output port of the first mid-infrared laser (1) and the second mid-infrared laser (2); when the visible light beam passes precisely through the center of the holes of the first aperture group (8) and the second aperture group (9) and reaches the output port of the first mid-infrared laser (1) and the second mid-infrared laser (2), it indicates that the visible light path has coincided with the initial optical axis reference. S3, Mid-infrared laser coupling Disconnect the first visible laser source (13) and the second visible laser source (14), connect the first reflective collimator (11) to the first output collimator (17) through the first mid-infrared fiber (15), and align the output end of the first output collimator (17) with the first detector (20); connect the second reflective collimator (12) to the second output collimator (18) through the second mid-infrared fiber (16), and align the output end of the second output collimator (18) with the second detector (21); after removing the temporary shield, turn on the first mid-infrared laser (1) and the second mid-infrared laser (2), and by coordinating and finely adjusting the spatial position of the third reflector (5) and the fourth reflector (6), make the mid-infrared laser output by the first mid-infrared laser (1) and the second mid-infrared laser (2) precisely coincide with the calibrated visible light path, so that a stable light signal is received on the first detector (20) and the second detector (21), and the coupling of the dual-band laser is completed; S4, Synchronous Calibration S4.1 Visible light guiding etalon alignment: Disconnect the second output collimator (18) from the second mid-infrared fiber (16), and remove the second output collimator (18) and the second detector (21) from the optical path; connect the second visible laser source (14) to the second reflective collimator (12) through the second mid-infrared fiber (16) and turn it on; adjust the third aperture group (10) set between the second reflective collimator (12) and the semi-transparent mirror (7) to ensure that the visible light spot output from the second reflective collimator (12) passes through the center of the aperture of each aperture in the third aperture group (10) in sequence to establish the coaxiality of the optical axis; Subsequently, the standard is placed between the third aperture group (10) and the semi-transparent mirror (7), and the position and tilt angle of the standard are adjusted so that the visible light spot reflected back from the surface of the standard passes through the center of the third aperture group (10) in the opposite direction, indicating that the standard has achieved normal incident alignment. S4.2, Mid-infrared laser synchronous calibration: Keep the position of the etalon unchanged, and place the second detector (21) behind the etalon. Turn on the two first mid-infrared lasers (1) and the second mid-infrared laser (2). Collect the interference signal generated by the etalon through the second detector (21). By analyzing the frequency characteristics of the interference signal, realize the synchronous frequency calibration of the dual-band laser. S5. Coupling and Calibration Effect Verification Steps The output signals of the first detector (20) and the second detector (21) are synchronously connected to the oscilloscope. The output of the signal optical path is collected through the first detector (20), and the interference signal generated by the etalon is collected through the second detector (21). The coupling efficiency is verified by observing the stability of the signal strength of the first detector (20), and the synchronous calibration effect is verified by observing the stability of the interference signal of the second detector (21).

8. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling method according to claim 7, characterized in that: In step S2, the light spots from the first reflective collimator (11) and the second reflective collimator (12) are made to overlap on the third reflective mirror (5) by fine-tuning the semi-transparent and semi-reflective mirror (7). Based on the symmetrical optical characteristics of the semi-transparent and semi-reflective mirror (7), the light spots on the fourth reflective mirror (6) are simultaneously overlapped.

9. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling method according to claim 7, characterized in that: In steps S2 and S3, a temporary shielding plate is placed in front of the light output ports of the first mid-infrared laser (1) and the second mid-infrared laser (2) to effectively protect the laser output ports from direct damage by strong visible light during the visible light guidance and debugging process.

10. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling method according to claim 7, characterized in that: The synchronous frequency calibration in step S4.2 is achieved by analyzing the interference signal received by the second detector (21) in real time, extracting the periodicity and phase information of the interference signal, and combining it with the free spectral range parameters of the etalon to realize the synchronous monitoring and stability evaluation of the output frequencies of the first mid-infrared laser (1) and the second mid-infrared laser (2).

11. The visible light-guided dual-wavelength infrared laser synchronous calibration and coupling method according to claim 7, characterized in that: In step S5, the output signals of the first detector (20) and the second detector (21) are connected to the oscilloscope through synchronous triggering, and are synchronously displayed and compared in the time domain, thereby ensuring the consistency of the acquisition time of the dual-band laser signals and providing a reliable timing reference for subsequent data processing.

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