Intelligent control anti-locking cooperative output ultrafast laser system and control method thereof

Abstract

The application relates to the technical field of lasers, and provides an intelligent regulation and control anti-lost lock cooperative output ultrafast laser system and a control method thereof.The intelligent regulation and control anti-lost lock cooperative output ultrafast laser system comprises a pump module used for transmitting pump light; a first beam splitter is arranged on the light path of the pump light, and a first input end of the first beam splitter is connected with the pump module; an input end of a dispersion filter assembly is connected with a first output end of the first beam splitter, the dispersion filter assembly is used for dispersion compensation, and laser light is output; a first pulse width adjusting assembly and a second pulse width adjusting assembly are respectively connected with different output ends of the dispersion filter assembly; and first laser light and second laser light are output. The intelligent regulation and control anti-lost lock cooperative output ultrafast laser system significantly improves the flexibility, process development efficiency and adaptability of multi-pulse width pulse output, and meets the differentiated requirements of different high-precision application scenarios.

Description

Technical Field

[0001] This application relates to the field of laser technology, and in particular to an intelligent control system for preventing loss of lock and a collaborative output ultrafast laser system and its control method. Background Technology

[0002] Ultrafast lasers are devices capable of generating laser pulses with pulse widths ranging from picoseconds to femtoseconds. Due to their extremely short pulse duration and extremely high peak power, ultrafast lasers can achieve a "cold processing" effect during interaction with matter, that is, to achieve ultra-fine processing of materials with almost no heat-affected zone.

[0003] Conventional industrial-grade ultrafast lasers are mostly single-output port designs, with a narrow adjustable range for output pulse width and center wavelength. This makes them unsuitable for applications such as precision micromachining, biomedical imaging, and scientific research, which face diverse processing materials and varied processing requirements. To achieve multi-pulse width laser output, multiple pulse width output ports can be incorporated into the laser. However, such multi-pulse width lasers are typically limited to adjustment within the same time scale, unable to achieve simultaneous output of dual pulse widths across femtosecond and picosecond time scales. Furthermore, the pulse width adjustment method is coarse and lacks precision. If users need to switch between femtosecond and picosecond pulses, they still need to replace the laser seed source or even the entire laser, which is not only cumbersome and costly but also severely reduces process development efficiency and production flexibility. Summary of the Invention

[0004] The intelligent control and anti-lockout collaborative output ultrafast laser system and its control method provided in this application improve the efficiency and flexibility of laser process development.

[0005] The first aspect of this application provides an intelligent controlled anti-lockout cooperative output ultrafast laser system, comprising: a pump module configured to transmit pump light; a first beam splitter disposed in the optical path of the pump light, with its first input terminal connected to the pump module; a dispersion filter component disposed on the side of the first beam splitter away from the pump module, its input terminal connected to the first output terminal of the first beam splitter, and configured to perform dispersion compensation to output laser light; and a pulse width modulation component, including a first pulse width modulation component and a second pulse width modulation component, the first and second pulse width modulation components being respectively connected to different output terminals of the dispersion filter component; the first pulse width modulation component being configured to perform dispersion compensation on the laser light using a first pulse width modulation mechanism to output a first laser light; and the second pulse width modulation component being configured to perform dispersion compensation on the laser light using a second pulse width modulation mechanism to output a second laser light; wherein the first pulse width modulation mechanism and the second pulse width modulation mechanism are different, and the pulse widths of the first laser light and the second laser light are different.

[0006] In some feasible implementations, the dispersion filtering component includes a second beam splitter and a first grating pair module; the first input of the second beam splitter is connected to the first output of the first beam splitter, and the first output of the second beam splitter is connected to the first grating pair module; the first grating pair module is configured to receive laser light and perform dispersion compensation on the laser light; the dispersion filtering component also includes a third beam splitter and a base module; the first input of the third beam splitter is connected to the first grating pair module; the second output of the second beam splitter is connected to the second input of the third beam splitter, and the connecting optical fiber between the second output of the second beam splitter and the second input of the third beam splitter is fixed on the base module; wherein, the optical path between the first output of the second beam splitter and the first input of the third beam splitter is the first optical path, and the optical path between the second output of the second beam splitter and the connecting optical fiber between the base modules is the second optical path; the first optical path and the second optical path are different to filter the laser light.

[0007] In some feasible implementations, the first pulse width adjustment component is connected to the dispersion filtering component. The first pulse width adjustment component includes a third fiber collimator and a second grating pair module. The input end of the third fiber collimator is connected to the output end of the third beam splitter. The third fiber collimator is configured to collimate the laser and then direct it into the second grating pair module. The second grating pair module is configured to use the first pulse width adjustment mechanism to compensate for the dispersion value of the first fiber connection segment. The first fiber connection segment includes the connecting fiber between the third beam splitter and the third fiber collimator.

[0008] In some feasible implementations, the dispersion filtering component is also connected to the second input of the first beam splitter, and the second pulse width adjustment component is connected to the second output of the first beam splitter. The second pulse width adjustment component includes a circulator and an adjustable fiber stretcher. The first port of the circulator is connected to the second output of the first beam splitter. The second port of the circulator is connected to the adjustable fiber stretcher. The intelligent control anti-lockout cooperative output ultrafast laser system also includes a fourth fiber collimator. The third port of the circulator is connected to the fourth fiber collimator. The adjustable fiber stretcher is configured to compensate for the dispersion value of the second fiber connection segment using the second pulse width adjustment mechanism. The second fiber connection segment includes the connecting fiber between the first beam splitter and the fourth fiber collimator.

[0009] In some feasible implementations, the first grating pair module includes a first grating pair and a first displacement stage; the first grating in the first grating pair is disposed on the first displacement stage, and the first displacement stage is configured to drive the first grating to move along the normal direction of the first grating to adjust the first grating pair spacing of the first grating pair; the first grating pair module is also configured to perform dispersion compensation on the first grating pair spacing.

[0010] The control method for an intelligently controlled anti-lock-out cooperative output ultrafast laser system provided in the second aspect of this application, applied to the intelligently controlled anti-lock-out cooperative output ultrafast laser system, includes: determining the correspondence between the stretching amount and the center wavelength of the base module based on the first grating pair spacing set in the dispersion filter component, the first stretching amount set of the base module in the dispersion filter component, and the first center wavelength set in the dispersion filter component; the first center wavelength in the first center wavelength set corresponds one-to-one with the first stretching amount in the first stretching amount set; using the stretching amount to compensate for the optical path difference in the dispersion filter component, controlling the optical path difference to be constant; compensating for the dispersion value of the first fiber connection segment based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component; and compensating for the dispersion value of the first fiber connection segment based on the second pulse width set of the second pulse width adjustment component. The dispersion values ​​of the adjustable fiber stretcher in the second pulse width adjustment component are used to compensate for the dispersion value of the second fiber connection segment. A dataset is established, which includes a multi-dimensional feature vector. The multi-dimensional feature vector includes the first target center wavelength, the first target pulse width, the second target pulse width, the first measured center wavelength, the first measured pulse width, the second measured pulse width, the measured adjustment amount of the first grating spacing, the measured adjustment amount of the second grating spacing, the first measured stretching amount of the base module, and the measured dispersion value of the second pulse width adjustment component. A dual-pulse width collaborative prediction model is trained using the dataset. The input of the trained dual-pulse width collaborative prediction model is the multi-dimensional feature vector, and the output is the adjustment amount of the first grating spacing, the adjustment amount of the second grating spacing, the first stretching amount of the base module, the pump power adjustment amount, and the dispersion value adjustment amount of the second pulse width adjustment component. The dual-pulse width collaborative prediction model is optimized using a Bayesian optimization algorithm.

[0011] In some feasible implementations, within the stable mode-locked pump power range of the pump light, the first grating pair spacing set, the first stretching amount set of the base module, and the first center wavelength set corresponding to the first stretching amount set are collected; the first grating pair spacing adjustment amount is determined based on the first grating pair spacing set; the correspondence between the stretching amount and the center wavelength is determined based on the first grating pair spacing set, the first center wavelength set, and the first stretching amount set; wherein, the absolute value of the maximum value of the first grating pair spacing adjustment amount is within a first preset range, and the first stretching amount of the base module is within a second preset range, and the first preset range is different from the second preset range.

[0012] In some feasible implementations, the dispersion value of the first optical fiber connection segment is compensated based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component, including: determining the negative dispersion value of the first pulse width adjustment component based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component; compensating the dispersion value of the first optical fiber connection segment based on the negative dispersion value; the absolute value of the negative dispersion value is greater than or equal to the absolute value of the dispersion value of the first optical fiber connection segment.

[0013] In some feasible implementations, a dual-pulse width collaborative prediction model is trained using a dataset, including: constructing a dual-pulse width collaborative prediction model, which is a nonlinear prediction model that incorporates an attention mechanism, and the dual-pulse width collaborative prediction model includes an input layer, an attention layer, a hidden layer, and an output layer connected in sequence; and training the dual-pulse width collaborative prediction model by combining the dataset and the priority of preventing loss of lock.

[0014] In some feasible implementations, a Bayesian optimization algorithm is used to optimize the dual-pulse-width collaborative prediction model, including: selecting a gradient boosting tree as a surrogate model and constructing an objective function; wherein the objective function includes a first objective function, a second objective function, a third objective function, and a fourth objective function, the first objective function is used to maximize mode-locking stability, the second objective function is used to minimize the pulse width error of the first laser, the third objective function is used to minimize the pulse width error of the second laser, and the fourth objective function is used to minimize the first center wavelength error; constructing a constraint function; in the constraint function, the weight values ​​corresponding to different mode-locking states are different; constructing a multi-objective expectation improved acquisition function that integrates target priorities; in the multi-objective expectation improved acquisition function, the target priority coefficients corresponding to different mode-locking states are different; and optimizing the dual-pulse-width collaborative prediction model based on the objective function, the constraint function, and the multi-objective expectation improved acquisition function.

[0015] The control method for an intelligent controlled anti-lock-breakage coordinated output ultrafast laser system provided in the second aspect of this application establishes a coordinated control mechanism for dispersion compensation and spectral filtering, linking the parameters of dispersion adjustment and filtering together. This ensures the stability of filtering characteristics and achieves precise compensation for intracavity dispersion. Simultaneously, it incorporates an intelligent prediction model with mode-locking priority and a dynamically constrained multi-objective optimization algorithm to construct an intelligent control logic of "mode-locking stability priority and precise pulse width adaptation," dynamically balancing various performance indicators without manual intervention. This effectively solves the problems of coarse pulse width adjustment, easy mode-locking instability, and insufficient hardware reliability in existing technologies. It also significantly improves the flexibility of multi-pulse width output and process development efficiency, meeting the differentiated needs of various high-precision application scenarios. Attached Figure Description

[0016] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of an intelligent control anti-lockout cooperative output ultrafast laser system provided in an embodiment of this application;

[0018] Figure 2This is a schematic diagram of the structure of a first grating pair module provided in an embodiment of this application;

[0019] Figure 3 This is a simplified structural diagram of an intelligent control anti-lockout cooperative output ultrafast laser system provided in an embodiment of this application;

[0020] Figure 4 This is one of the flowcharts illustrating a control method for an intelligent control anti-lockout cooperative output ultrafast laser system provided in this application embodiment;

[0021] Figure 5 This is the second flowchart illustrating a control method for an intelligent control anti-lockout collaborative output ultrafast laser system provided in this application embodiment.

[0022] Illustration markings:

[0023] 1. Mode-locking module; 2. Fiber polarizer; 3. Gain module; 4. Pump module; 5. Wavelength division multiplexer; 6. First beam splitter; a1. Dispersion filter assembly; 7. Second beam splitter; 8. First fiber collimator; 9. First grating pair module; 901. First mirror; 902. First grating; 903. Second grating; 904. First roof mirror; 905. First displacement stage; 906. First photoelectric sensor; 10. Second fiber collimator; 11. Third beam splitter; 12. Fourth beam splitter; 13. Fiber isolation beam splitter; 14. First base; 15. Second base; 16. Circulator; 17. Adjustable 18. Fiber optic stretcher; 19. Third fiber optic collimator; 20. First optical beam splitter; 21. Second optical beam splitter; 22. First frequency domain data acquisition card; 23. First time domain data acquisition card; 24. Fourth fiber optic collimator; 25. Second grating pair module; 26. Second time domain data acquisition card; 27. Second frequency domain data acquisition card; 28. Third optical beam splitter; 29. ​​Fourth optical beam splitter; 30. First power data acquisition card; 31. Second power data acquisition card; 32. Third power data acquisition card; 33. First output window; 34. Second output window; 35. Algorithm control module; 36. Main control module. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are all within the protection scope of this application.

[0025] In the following description, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0026] Furthermore, in this application, directional terms such as "upper," "lower," "inner," and "outer" are defined relative to the indicated placement of the components in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the placement of the components in the accompanying drawings.

[0027] Ultrafast lasers typically refer to devices capable of generating laser pulses with pulse widths in the picosecond to femtosecond range. Due to their extremely short pulse duration and extremely high peak power, ultrafast lasers can achieve a "cold processing" effect during interaction with matter, enabling ultra-precise machining of materials with almost no heat-affected zone. This unique advantage makes them irreplaceable in fields such as precision micromachining, cutting-edge scientific research, biomedical imaging and surgery, high-speed optical communication, and nonlinear optical frequency combs. In the development of ultrafast lasers, fiber lasers have stood out due to their unique advantages. With the increasing maturity of fiber fabrication technology, the performance of mode-locked oscillators using fiber as the gain medium has improved significantly. Compared to traditional solid-state laser oscillators, fiber lasers exhibit superior mechanical stability, compact size, excellent beam quality, and maintenance-free or low-maintenance costs. These advantages make them more adaptable to the harsh environments of industrial settings, thus gradually replacing some traditional solid-state lasers and becoming the mainstream technology for ultrafast laser seed sources.

[0028] However, conventional industrial-grade ultrafast lasers often employ a single-output-port design, typically providing only one output port. Furthermore, the output pulse width and center wavelength are usually within a narrow adjustable range, making it difficult to adapt to diverse application requirements. In precision micromachining, biomedical imaging, and scientific research, facing diverse processing materials such as metals, semiconductors, polymers, and transparent brittle materials, as well as different processing needs such as cutting, drilling, and surface structuring, pulse width, as a key parameter affecting processing accuracy and heat-affected zone size, often requires exploration and optimization of laser parameters to achieve the best processing results. Pulse width is one such key parameter, directly impacting processing accuracy, heat-affected zone size, and nonlinear interaction efficiency. Currently, when users need to change the pulse width, the conventional approach is to replace different seed sources, or even the entire laser, which is not only cumbersome and time-consuming but also severely restricts process development efficiency and production flexibility.

[0029] Figure 1 This is a schematic diagram of a smart control anti-lockout cooperative output ultrafast laser system provided in an embodiment of this application.

[0030] To solve the above technical problems, see Figure 1 This application provides an intelligent control anti-lockout cooperative output ultrafast laser system.

[0031] The intelligent control anti-lockout collaborative output ultrafast laser system includes: mode-locking module 1, fiber polarizer 2, gain module 3, pump module 4, wavelength division multiplexer 5, first beam splitter 6, dispersion filter component, and pulse width adjustment component.

[0032] Specifically, in this intelligent controlled anti-lock-breakage cooperative output ultrafast laser system, starting with mode-locking module 1, the output of mode-locking module 1 is sequentially connected to fiber polarizer 2, gain module 3, and wavelength division multiplexer 5. Mode-locking module 1 is used to generate mode-locked pulses, achieving long-term stability of the intelligent controlled anti-lock-breakage cooperative output ultrafast laser system. Fiber polarizer 2 ensures that the laser always maintains the same polarization state during transmission; gain module 3 converts the pump light into the target laser and compensates for transmission loss, increasing the output energy.

[0033] Both pump module 4 and gain module 3 are connected to wavelength division multiplexer 5. Pump module 4 is used to transmit pump light. The pump light is transmitted to gain module 3 via wavelength division multiplexer 5, where it is absorbed by the gain medium to form population inversion. Subsequently, the optical signal is amplified through stimulated emission to generate laser light.

[0034] The first beam splitter 6 is positioned in the optical path of the pump light, and its first input terminal is connected to the pump module 4 via a wavelength division multiplexer 5. The first beam splitter 6 can be used for beam splitting and beam combining.

[0035] The dispersion filter component is located on the side of the first beam splitter 6 away from the pump module 4. The input end of the dispersion filter component is connected to the first output end of the first beam splitter 6. The dispersion filter component is configured to perform dispersion compensation in order to output laser light.

[0036] Specifically, the dispersion filter component can achieve the dual functions of dispersion and filtering. In this way, after the laser enters the dispersion filter component, not only can the dispersion value be precisely adjusted, but the center wavelength of the laser can also be adjusted simultaneously.

[0037] The pulse width modulation component includes a first pulse width modulation component and a second pulse width modulation component, which are respectively connected to a dispersion filtering component. The first pulse width modulation component is used to perform dispersion compensation on the laser using a first pulse width modulation mechanism to output a first laser. The second pulse width modulation component is used to perform dispersion compensation on the laser using a second pulse width modulation mechanism to output a second laser.

[0038] Specifically, after the laser undergoes initial dispersion and filtering, the dispersed laser light is output through the dispersion filtering component and transmitted to the first pulse width adjustment component and the second pulse width adjustment component for further dispersion adjustment. The first and second pulse width adjustment mechanisms differ, resulting in different pulse widths for the first and second lasers. This dual-path pulse width control structure enables the modulation of lasers with different pulse widths, thus meeting the diverse pulse width accuracy and flexibility requirements of various application scenarios and achieving targeted pulse width modulation.

[0039] It should be emphasized that the “connection” or “linkage” mentioned in this application can include direct connection and indirect connection. Indirect connection can achieve the coupling and transmission of signals or optical paths through intermediate media or components, and the interfaces between components must meet the requirements of optical matching and mechanical stability.

[0040] The intelligent control and anti-lockout collaborative output ultrafast laser system provided in this application establishes a collaborative control mechanism for dispersion compensation and spectral filtering, linking the parameters of dispersion adjustment and filtering. This ensures the stability of filtering characteristics and achieves precise compensation for intracavity dispersion, effectively solving the problems of coarse pulse width adjustment, easy mode-locking instability, and insufficient hardware reliability in existing technologies. It significantly improves the flexibility, process development efficiency, and adaptability of multi-pulse width output, meeting the differentiated needs of different high-precision application scenarios.

[0041] In some feasible implementations, the dispersion filtering component may include a second beam splitter 7 and a first grating pair module 9; the first input terminal of the second beam splitter 7 is connected to the first output terminal of the first beam splitter 6, and the first output terminal of the second beam splitter 7 is connected to the first grating pair module 9; the first grating pair module 9 is configured to receive laser light and perform dispersion compensation on the laser light.

[0042] Specifically, after the laser enters the dispersion filter component, the second beam splitter 7 splits the laser beam, and one laser beam enters the first grating module 9 for dispersion adjustment.

[0043] In one specific implementation, the dispersive filtering component may further include a first fiber collimator 8 and a second fiber collimator 10. Both the first fiber collimator 8 and the second fiber collimator 10 are used for spatial collimation of the beam. The first fiber collimator 8 is disposed between the second beam splitter 7 and the first grating pair module 9. One end of the first fiber collimator 8 is connected to the second beam splitter 7, and the other end is the light-emitting end, which is positioned opposite to the first grating pair module 9. That is, the first output end of the second beam splitter 7 is indirectly connected to the first grating pair module 9 through the first fiber collimator 8. The second fiber collimator 10 is disposed on the opposite side of the first grating pair module 9 from the first fiber collimator 8. After passing through the first grating pair module 9, the laser beam is incident on the second fiber collimator 10.

[0044] Figure 2 This is a schematic diagram of the structure of a first grating pair module provided in an embodiment of this application.

[0045] Combination Figure 1 and Figure 2 As shown, in the aforementioned optical path, laser light is injected into the first grating pair module 9 in the form of spatial light. The first grating pair module 9 may include: a first reflector 901, a first grating pair, a first roof mirror 904, a first displacement stage 905, and a first photoelectric sensor 906. The first grating 902 in the first grating pair is disposed on the first displacement stage 905, and the second grating 903 in the first grating pair is disposed opposite to the first grating 902. The first grating 902 and the second grating 903 are arranged at Brewster's angle, utilizing the diffraction effect to spatially separate components of different wavelengths in the incident pulse, introducing positive dispersion. The first reflector 901 is disposed in the optical path between the first grating 902 and the second grating 903, and the first reflector 901 is located between the first photoelectric sensor 906 and the second grating 903.

[0046] Specifically, the first grating pair is a pair of diffraction gratings. The first displacement stage 905 can move the first grating 902 along the normal direction of the first grating 902, thereby adjusting the spacing between the first grating pairs. This allows for dispersion compensation when the spacing between the first grating pairs changes. After secondary diffraction, the beam produces an opposite group delay, i.e., negative dispersion, which cancels the initial chirp of the pulse and achieves time-domain compression. The first roof mirror 904 is used to change the propagation direction of the beam and introduce a height difference, so that the compressed laser is output through the first reflecting mirror 901: 99% of the energy is reflected to the subsequent optical path, and the remaining 1% of the energy is transmitted to the first photoelectric sensor 906.

[0047] In some feasible implementations, the negative dispersion value provided by the dispersion filtering component It can be calculated using the following formula (1):

[0048] (1)

[0049] in, The first grating pair spacing, For Brewster Point, The speed of light in a vacuum. The grating constant is Let λ be the center wavelength of the incident light. In formula (1), the dispersion value is directly related to the grating pair spacing. Therefore, the first displacement stage 905 moves precisely along the normal direction of the first grating 902 under the drive of the algorithm, and the dispersion value is continuously controlled by adjusting the first grating pair spacing.

[0050] In some feasible implementations, the dispersion filtering component also includes a third beam splitter 11 and a base module; the first input end of the third beam splitter 11 is connected to the first grating pair module 9 through the second fiber collimator 10; the second output end of the second beam splitter 7 is connected to the second input end of the third beam splitter 11, and the connecting fiber between the second output end of the second beam splitter 7 and the second input end of the third beam splitter 11 is fixed on the base module.

[0051] In these feasible implementations, the first grating pair module 9 is connected to the first output end of the third beam splitter 11 via the second fiber collimator 10. The second beam splitter 7 can be a 1×2 fiber beam splitter.

[0052] The other laser beam split from the second beam splitter 7 is transmitted to the third beam splitter 11 after passing through the base module. The base module may include a first base 14 and a second base 15 arranged sequentially. The optical path length between the first output end of the second beam splitter 7 and the first input end of the third beam splitter 11 is the first optical path length L1. That is, the first optical path length L1 is the optical path length traversed by the laser as it passes through the second beam splitter 7, the first fiber collimator 8, the first grating pair module 9, and the second fiber collimator 10, and is transmitted to the third beam splitter 11. The optical path length between the second output end of the second beam splitter 7 and the second input end of the third beam splitter 11 via the connecting fiber between the base modules is the second optical path length L2. That is, the second optical path length L2 is the optical path length traversed by the laser as it passes through the second beam splitter 7, the first base 14, and the second base 15, and is transmitted to the third beam splitter 11. The first optical path length L1 is different from the second optical path length L2 to filter the laser beam. The third beam splitter 11 may be a 1×2 fiber beam splitter.

[0053] Specifically, the ends of the second beam splitter 7 and the third beam splitter 11 are directly connected. Considering the stability of this intelligent control anti-lockout cooperative output ultrafast laser system, the coating layer of part of the optical fiber is removed at a position greater than 10cm from the fiber splice point, and the optical fiber is fixed on the first base 14 and the second base 15 with UV curing adhesive, keeping the decoated part in the middle position between the first base 14 and the second base 15. The first base 14 and the second base 15 can be motorized bases with precision adjustment functions, and they can be controlled to move. Since the first optical path L1 is different from the second optical path L2, the laser beam is split by the second beam splitter 7 and then reunited at the third beam splitter 11. Since the two beams have different optical paths, interference will occur when they reunite, thereby realizing the function of wavelength selective filtering. The free spectral range of this filter can be calculated by the following formula (2):

[0054] (2);

[0055] in, The wavelength difference between two adjacent transmission peaks in the free spectral range. For effective refractive index, .

[0056] Visibility, also known as interference fringe contrast, is a core indicator for evaluating the quality of interference. When two coherent beams of light are superimposed in space, the total light intensity... The distribution can be calculated using the following formula (3):

[0057] (3);

[0058] in, and These represent the light intensities of the two beams, Let the phase difference between the two beams of light be the phase difference when When the total light intensity changes, At the maximum value and minimum value The visibility V can be calculated using the following formula (4) as it varies between the two values:

[0059] (4);

[0060] when = hour, =1 indicates the strongest contrast in the interference fringes, resulting in the best interference effect and the strongest filtering capability. Typically, a 50:50 beam splitter is used. Considering the losses caused by grating deformation during stretching and the grating's transmission efficiency, this application further limits the beam splitting ratio of the second beam splitter 7 and the third beam splitter 11 to ensure 0.9 ≤ 1. ≤1. The single-pass transmission efficiency of the grating is approximately 96%, and the overall transmittance is approximately 85%, corresponding to a loss of approximately 0.705 dB. When the grating is stretched to its maximum length, the loss is approximately 0.09 dB, thus the beam splitting ratio is set between 44:56 and 63:37. In the embodiments of this application, a beam splitting ratio of 55:45 is preferred, allowing for a slightly longer upper arm to compensate for grating loss while leaving a certain margin.

[0061] In one specific implementation, the intelligent controlled anti-lockout coordinated output ultrafast laser system may further include a fourth beam splitter 12 and a fiber-optic isolated beam splitter 13. The fourth beam splitter 12 is located at the output end of the third beam splitter 11. After passing through the dispersive filter component, the laser can sequentially pass through the fourth beam splitter 12 and the fiber-optic isolated beam splitter 13 before returning to the first beam splitter 6, forming a loop structure to ensure that the laser always propagates in a clockwise direction within the loop. It is important to emphasize that the clockwise direction is... Figure 1 The locations shown are illustrative and not specific to any particular location.

[0062] Specifically, in this implementation, the first output terminal of the fourth beam splitter 12 is connected to the fiber optic isolation beam splitter 13, and the second output terminal of the fourth beam splitter 12 is connected to the first pulse width adjustment component. The fourth beam splitter 12 can be a 1×2 fiber optic beam splitter.

[0063] In this implementation, see [link to relevant documentation]. Figure 1 As shown, the first pulse width adjustment component is indirectly connected to the dispersion filtering component through the fourth beam splitter 12. The first pulse width adjustment component may include a third fiber collimator 18 and a second grating pair module 24. The input end of the third fiber collimator 18 is connected to the output end of the third beam splitter 11 through the fourth beam splitter 12. The third fiber collimator 18 is configured to collimate the laser light before it enters the second grating pair module 24. The second grating pair module 24 is configured to use the first pulse width adjustment mechanism to compensate for the dispersion value of the first fiber connection segment. The first fiber connection segment includes the connecting fiber between the third beam splitter 11 and the third fiber collimator 18. That is, the first fiber connection segment can be the connecting fiber between the laser light transmitted from the dispersion filtering component to the third fiber collimator 18.

[0064] Specifically, the structure of the second grating pair module 24 can be the same as that of the first grating pair module 9. The second grating pair module 24 may include a second reflector, a third grating, a fourth grating, a second moving stage, a second roof mirror, and a second photodetector (not shown in the figure). The dispersion adjustment of the laser by the second grating pair module 24 can be referred to the above formulas (1) to (4).

[0065] In some feasible implementations, the dispersion filtering component can also be connected to the second input terminal of the first beam splitter 6 via an optical fiber isolation beam splitter 13, and the second pulse width adjustment component can be connected to the second output terminal of the first beam splitter 6. In this way, after the laser light enters the dispersion filtering component to perform dispersion and filtering operations, it can not only be transmitted to the first pulse width adjustment module through the first output terminal of the fourth beam splitter 12, but also re-enter the first beam splitter 6 through the optical fiber isolation beam splitter 13, and be input to the second pulse width adjustment component from the second output terminal of the first beam splitter 6. The first beam splitter 6 can be a 2×2 optical fiber beam splitter.

[0066] The second pulse width adjustment component may include a circulator 16 and an adjustable fiber stretcher 17. The first port of the circulator 16 is connected to the second output of the first beam splitter 6; the second port of the circulator 16 is connected to the adjustable fiber stretcher 17. The intelligent control anti-lockout cooperative output ultrafast laser system also includes a fourth fiber collimator 23; the third port of the circulator 16 is connected to the fourth fiber collimator 23. The adjustable fiber stretcher 17 is configured to compensate for the dispersion value of the second fiber connection segment using the second pulse width adjustment mechanism, and the compensated value is output from the third port of the circulator 16. The second fiber connection segment includes the connecting fiber between the first beam splitter 6 and the fourth fiber collimator 23.

[0067] In this way, by setting the first pulse width adjustment component and the second pulse width adjustment component, dual-path dispersion collaborative compensation can be achieved after the laser is output from the dispersion filtering component, so as to ensure the output of the laser pulse required.

[0068] In this embodiment, the first laser can be a femtosecond laser, and the second laser can be a picosecond laser. This enables the ultrafast laser to stably output picosecond or femtosecond-level pulses while maintaining stable operation in a mode-locked state. The establishment and maintenance of mode-locking require the net dispersion within the cavity to be controlled within a suitable range. Under this condition, nonlinear effects and dispersion can achieve dynamic equilibrium, thereby forming and maintaining a narrow pulse width output at the transformation limit. Since pulsed lasers are susceptible to group velocity dispersion when propagating in optical fibers, resulting in different propagation speeds for different frequency components and causing pulse broadening, the first grating provides adjustable negative dispersion to module 9 to compensate for the positive dispersion introduced by the optical fiber in the resonant cavity.

[0069] Figure 3This is a simplified structural diagram of an intelligent control anti-lockout cooperative output ultrafast laser system provided in an embodiment of this application.

[0070] See Figure 3 As shown, taking a femtosecond laser as the first laser and a picosecond laser as the second laser as an example, the following conditions must be met to achieve stable mode-locking and output the target pulse width. Where D represents the dispersion value, D ABCDE D1 represents the dispersion value provided by all optical fibers within the resonant cavity of the dispersion filtering component. D1 is the maximum dispersion value that the first grating pair module 9 can provide. That is, the dispersion provided by the first grating pair module 9 essentially cancels out the total dispersion of the optical fibers within the cavity, thus making the net system dispersion close to zero. Specifically, the spacing Lg between the first grating pairs when providing the required negative dispersion can be determined using formula (1). i When the spacing of the first grating is adjusted to a suitable value, the net dispersion of the entire intelligent control anti-lockout collaborative output ultrafast laser system will approach zero (i.e., near-zero dispersion state). At this time, the mode-locked operation is most stable, laying the foundation for achieving the target pulse output.

[0071] Because the laser light is further dispersed after passing through the CDF segment of the optical fiber, in order to obtain the target femtosecond pulse output, it is required that... , where D CDF D2 represents the dispersion value provided by the CDF segment fiber, and D2 is the maximum dispersion value that the second grating pair module 24 can provide. The laser light travels from the first port to the second port of the circulator 16 to the adjustable fiber stretcher 17, where it is stretched to a certain dispersion value and then output from the third port of the circulator 16. BGH D1 represents the dispersion value introduced by the BGH segment of the optical fiber, and D2 represents the dispersion value provided by the adjustable fiber stretcher 17. Introduced second-order dispersion The following formula can be used for calculation:

[0072] (5)

[0073] in, This allows for direct output of picosecond pulse widths within the cavity. The target picosecond pulse width is defined, and finally, the target picosecond pulse is output through the second output window 33.

[0074] See also the following for some feasible implementation methods. Figure 1 As shown, the intelligent control anti-lockout collaborative output ultrafast laser system may further include: a first output window 32 and a second output window 33. The first output window 32 is set in the output optical path of the second grating pair module 24 and is used to output the first laser. The second output window 33 is set in the output optical path of the fourth fiber collimator 23 and is used to output the second laser.

[0075] In some feasible implementations, the intelligent control anti-lockout collaborative output ultrafast laser system may also include: a first optical beam splitter 19, a second optical beam splitter 20, a first frequency domain data acquisition card 21, and a first time domain data acquisition card 22.

[0076] Specifically, the first optical beam splitter 19 is disposed between the second grating pair module 24 and the first output window 32. The first laser can be split into two paths by the first optical beam splitter 19. One path is transmitted to the first output window 32 through the first optical beam splitter 19, and the other path is reflected by the first optical beam splitter 19 to the second optical beam splitter 20. The second optical beam splitter 20 then transmits the laser beam to the first frequency domain data acquisition card 21 and the first time domain data acquisition card 22 respectively for real-time monitoring of spectral characteristics.

[0077] In some feasible implementations, the intelligent control anti-lockout collaborative output ultrafast laser system may also include: a third optical beam splitter 27, a fourth optical beam splitter 28, a second frequency domain data acquisition card 26, and a second time domain data acquisition card 25.

[0078] Specifically, the third optical beam splitter 27 is positioned between the fourth fiber collimator 23 and the second output window 33. The second laser can be split into two paths by the third optical beam splitter 27. One path is transmitted to the second output window 33 via the third optical beam splitter 27, and the other path is reflected by the third optical beam splitter 27 to the fourth optical beam splitter 28. The fourth optical beam splitter 28 then transmits the laser beam to the second frequency domain data acquisition card 26 and the second time domain data acquisition card 25, respectively, for real-time monitoring of spectral characteristics.

[0079] In some feasible implementations, the intelligent control anti-lockout collaborative output ultrafast laser system may also include: a first power data acquisition card 29, a second power data acquisition card 30, and a third power data acquisition card 31.

[0080] Specifically, the first power data acquisition card 29 is connected to the fiber optic isolation beam splitter 13 and is used to detect the power value of the laser output by the laser. The second power data acquisition card 30 is connected to the first grating pair module 9 and is used to detect the power value of the laser inside the dispersive filter component. The third power data acquisition card 31 is connected to the second grating pair module 24 and is used to detect the power value of the laser inside the second pulse width component.

[0081] In some feasible implementations, the intelligent control anti-lockout collaborative output ultrafast laser system may also include: an algorithm control module 34 and a main control module 35.

[0082] The algorithm control module 34 is connected to the first frequency domain data acquisition card 21, the first time domain data acquisition card 22, the second frequency domain data acquisition card 26, the second time domain data acquisition card 25, the first power data acquisition card 29, the second power data acquisition card 30, the third power data acquisition card 31, the first base 14, the second base 15, the adjustable fiber stretcher 17, the first grating pair module 9, and the second grating pair module 24, respectively. The algorithm control module 34 is used to receive data provided by the acquisition cards and execute optimization algorithms and control logic. The main control module 35 is connected to the algorithm control module 34 and the pump module 4, respectively. The main control module 35 is used to receive instructions from the host computer and coordinate the collaborative work of each module.

[0083] In one specific implementation, when the pump power reaches the mode-locking threshold P1, for example 53mW, pulsed laser light is output. As the pump power continues to increase to P1... n For example, with a power output of 98mW, the pulse exhibits a splitting state. Therefore, the pump power operating range corresponding to stable mode-locking is... Typically, a pump power point slightly above the mode-locking threshold is selected for mode-locking, for example, 58mW. However, when tuning the center wavelength or pulse width, the intracavity loss will change. The first power data acquisition card 29 records the laser output power in real time. When the output power fluctuation exceeds 3% of the average output power, the main control module 35 starts to adjust the current of the pump module 4 to ensure that the output power stability rms < 0.5%. For example, the output power is 2.4mW, and the output power stability rms ≈ 0.32%.

[0084] The intelligent control and anti-lockout collaborative output ultrafast laser system provided in this application adopts an integrated collaborative architecture, effectively reducing production costs. Through the linkage of the dispersion filtering component and the pulse width adjustment component, multiple independent laser generating units are eliminated, enabling flexible multi-pulse width control within a single system. The structure is more compact and requires no additional optical path switching components. Furthermore, intelligent algorithms can avoid stability fluctuations caused by hardware switching, resulting in superior pulse width tuning accuracy and adaptability.

[0085] Corresponding to the aforementioned embodiments of the intelligent control anti-lockout cooperative output ultrafast laser system, this application also provides a control method for the intelligent control anti-lockout cooperative output ultrafast laser system.

[0086] Figure 4 This is one of the flowcharts illustrating a control method for an intelligent control anti-lockout cooperative output ultrafast laser system provided in this application embodiment.

[0087] See Figure 4 As shown in the embodiments of this application, the control method of the intelligent control anti-lockout cooperative output ultrafast laser system may include the following steps S1 to S7.

[0088] Step S1: Based on the first grating pair spacing set in the dispersion filter component, the first stretching amount set of the base module in the dispersion filter component, and the first center wavelength set in the dispersion filter component, determine the correspondence between the stretching amount and the center wavelength of the base module; the first center wavelength in the first center wavelength set corresponds one-to-one with the first stretching amount in the first stretching amount set. The stretching amount of the base module refers to the stretching amount generated during the pulling of the optical fiber between the first base and the second base in the base module.

[0089] Step S1 may include steps S11 to S13.

[0090] Step S11: Within the stable mode-locked pump power range of the pump light, collect the first grating pair spacing set in the first grating pair, the first stretching amount set of the base module in the dispersive filter component, and the first center wavelength set corresponding to the first stretching amount set.

[0091] In this step, within the stable mode-locked pump power range Internally, it collects historical operating parameters of the acquisition system, including the first grating alignment and the first grating pair spacing set. Where i = 1, 2, 3, ..., n, is the first set of stretch amounts for the base module. and the set of first center wavelengths corresponding to the first stretching amount. .

[0092] Step S12: Determine the first grating pair spacing adjustment amount based on the first grating pair spacing set.

[0093] First grating spacing step value And the first grating adjusts the spacing amount .

[0094] Step S13: Determine the correspondence between the stretching amount and the center wavelength based on the first grating pair spacing set, the first center wavelength set, and the first stretching amount set; wherein, the absolute value of the maximum value of the first grating pair spacing adjustment amount is within a first preset range, the first stretching amount is within a second preset range, and the first preset range is different from the second preset range.

[0095] Determining the near-zero dispersion point using the dispersion compensation principle. ,satisfy Calculate the deviation between the current first grating pair spacing and the near-zero dispersion point. Based on the collected parameters, the unit tensile amount is calculated. The corresponding average change in center wavelength This is used to establish the quantitative correspondence between the stretching amount and the center wavelength.

[0096] (6)

[0097] in, and It is the change in two adjacent center wavelengths, the optical path difference between the two arms of the dispersive filter component. Combining with formula (2), the free spectral range (FSR) can be adjusted by changing the stretching amount ΔL. This step aims to establish a quantitative correspondence between the spacing, stretching amount, center wavelength, and FSR of the first grating pair using historical parameters, clarify hardware safety constraints, and define the first preset range: Second preset range: The subsequent coordinated adjustment provides data support, while verifying the matching between dispersion compensation and filtering characteristics.

[0098] Step S2: Use stretching to compensate for the optical path difference in the dispersive filter component and control the optical path difference to be constant.

[0099] Because the filtering function in the dispersive filter component needs to ensure the optical path difference between the two arms... Constant, first grating pair spacing varies This will directly cause the first optical path L1 to change synchronously, that is To maintain a constant optical path difference between the two arms and ensure filtering stability, the stretching amount needs to be adjusted. Compensate for optical path changes, so that The change in optical path due to grating stretching is Therefore, the synergistic regulation formula (7) is derived:

[0100] (7)

[0101] Set constraints: First grating spacing adjustment amount and ; stretching amount ≤3mm, when calculated At that time, take Synchronously correct the spacing adjustment of the first grating The first center wavelength satisfies This step establishes a forced linkage mechanism between the spacing and stretching of the first grating pair to avoid optical path difference imbalance caused by independent adjustment, such as filter failure, or hardware damage such as fiber stretching breakage or overtravel of the first grating pair spacing, thus ensuring the coordinated optimization of dispersion compensation and spectral filtering.

[0102] In traditional systems, independent adjustment of grating spacing and fiber stretching can easily lead to fiber breakage or grating overtravel. This application's embodiment ensures hardware safety through dual constraints: first, it clearly defines physical boundaries in the collaborative adjustment model and automatically corrects the adjustment amount through a linkage formula, such as synchronously reducing the grating spacing adjustment amount when the stretching exceeds the limit; second, it adds secondary verification during adjustment execution, performing boundary judgment on the adjustment amount output by the model and prioritizing a return to a safe state such as near-zero dispersion. Simultaneously, it employs a 55:45 fiber beam splitter to ensure interference visibility of 0.9≤V≤1, reducing fiber stretching loss and significantly improving the long-term operational reliability of the system.

[0103] Step S3: Based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component, compensate for the dispersion value of the first optical fiber connection segment.

[0104] Step S3 may include steps S31 and S32.

[0105] Step S31: Determine the negative dispersion value of the first pulse width adjustment component based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component.

[0106] Collect historical adjustment parameters of the first pulse width adjustment module, including the second grating pair spacing set. The second grating spacing step value The corresponding first pulse width set .

[0107] Step S32: Compensate the dispersion value of the first fiber optic connection segment based on the negative dispersion value; the absolute value of the negative dispersion value is greater than or equal to the absolute value of the dispersion value of the first fiber optic connection segment.

[0108] The negative dispersion provided by the second grating pair The negative dispersion value D of the first fiber optic connector CDF is compensated using this negative dispersion. CDF This ensures that fiber dispersion in the CDF segment is fully compensated.

[0109] Step S4: Based on the second pulse width set of the second pulse width adjustment component and the dispersion value set of the adjustable fiber stretcher in the second pulse width adjustment component, compensate for the dispersion value of the second fiber connection segment.

[0110] Collect historical adjustment parameters of the second pulse width modulation component, including the D3 set of dispersion values ​​of the adjustable fiber stretcher. Step value The corresponding second pulse width set Based on formula (5), the D3 constraint formula (8) is obtained as follows:

[0111] (8)

[0112] In this step, by establishing the parameter quantification relationship of the pulse width adjustment module, the dispersion compensation constraint boundary is clarified, providing a theoretical basis for the precise control of different pulsed lasers, such as femtosecond and picosecond dual pulses, and ensuring that the pulse width adjustment matches the overall system performance.

[0113] The control method for the intelligent control and anti-lockout coordinated output ultrafast laser system provided in this application achieves coordinated control of optical dispersion, filtering, and pulse width parameters directly by deeply integrating dispersion filtering components and pulse width adjustment modules without complex electrical signal modulation. The structure is more compact and has no additional electrical drive redundancy. At the same time, combined with an intelligent algorithm with mode-locking priority, it achieves continuous adjustment of femtosecond and picosecond pulse widths at the optical level. The tuning process does not require electrical signal relay, which balances mode-locking stability and pulse width accuracy, and avoids response delay and error caused by electro-optical conversion.

[0114] Step S5: Establish a dataset; the dataset includes multidimensional feature vectors, which include the first target center wavelength, the first target pulse width, the second target pulse width, the first measured center wavelength, the first measured pulse width, the second measured pulse width, the first grating spacing measured adjustment amount, the second grating spacing measured adjustment amount, the measured stretching amount of the base module, and the measured dispersion value of the second pulse width adjustment component.

[0115] In this step, the first frequency domain data acquisition card, the first time domain data acquisition card, the second frequency domain data acquisition card, and the second time domain data acquisition card can all synchronously acquire two pulse parameters and mode-locked state data at a sampling frequency of 1kHz. The valid sample set is retained through the clock synchronization signal of the main control module. :

[0116] When pump power If the signal-to-noise ratio (SNR) is less than 50 dB or there is no stable repetitive frequency peak in the radio frequency spectrum, it is determined to be a loss of lock, and the current spacing of the first grating pair is recorded. This triggers the lockout fallback mechanism. A 10-dimensional input feature vector is constructed. Integrate target parameters, measured parameters, and component status parameters:

[0117] .in , , These are the center wavelength of the first target, the pulse width of the first target, and the pulse width of the second target, respectively. These are the first measured center wavelength, the first measured pulse width, the second measured pulse width, the first grating spacing adjustment amount, the second grating spacing adjustment amount, the first measured stretching amount of the base module, and the measured dispersion value of the second pulse width adjustment component, respectively. The eigenvectors are standardized, mapping the eigenvalues ​​to the [0, 1] interval, eliminating dimensional differences. It can be calculated using the following formula (9):

[0118] (9)

[0119] in, To be the minimum value, This is the maximum value. After processing the data to obtain the dataset, it can be split into a training set and a test set in an 8:2 ratio. This allows for the construction of high-quality model input samples through data filtering, feature integration, and standardization, improving the generalization ability and adjustment accuracy of subsequent prediction models and providing a reliable data foundation for intelligent regulation.

[0120] Step S6: Train the dual-pulse-width collaborative prediction model using the dataset; the input of the trained dual-pulse-width collaborative prediction model is a multi-dimensional feature vector, and the output is the first grating pair spacing adjustment amount, the second grating pair spacing adjustment amount, the first stretching amount of the base module, the pump light power adjustment amount, and the dispersion value adjustment amount of the second pulse width adjustment component.

[0121] Step S6 may include steps S61 and S62.

[0122] Step S61: Construct a dual-pulse width collaborative prediction model. The dual-pulse width collaborative prediction model is a nonlinear prediction model that integrates an attention mechanism. The dual-pulse width collaborative prediction model includes an input layer, an attention layer, a hidden layer, and an output layer connected in sequence.

[0123] Step S62: Train a dual-pulse width collaborative prediction model by combining the dataset and the priority of preventing loss of lock.

[0124] A nonlinear prediction model with an integrated attention mechanism is constructed, and the priority of preventing loss of lock is embedded in the training of the model to achieve a collaborative mapping of model-lock stability priority and precise matching of pulse parameters. The dual-pulse width collaborative prediction model consists of an input layer x, an attention layer, two hidden layers and an output layer connected in sequence. Each hidden layer contains 180 neurons and uses the GELU activation function.

[0125] The input layer and output layer each include:

[0126] ;

[0127] Attention layer First hidden layer: ; This is the output feature vector of the first hidden layer; The weights of the first hidden layer, Here is the bias vector for the first hidden layer; for the second hidden layer: ; This is the output feature vector of the first hidden layer; The weights of the first hidden layer, The bias vector for the first hidden layer; Output layer: . For the weights of the output layer, This is the bias vector for the output layer. and For the attention weight matrix and bias, For feature dimension, =8e-5 is the norm L2 regularization coefficient. A weighted loss function is used to enhance the training priority of the mode-locked state, which can be calculated using the following formula (10):

[0128] (10);

[0129] in, This is a mold-locking status indicator. To ensure stable mold locking, Unlocked. To predict the mode-locking state for the model, =5 represents the weight of the mode-locking state, which is higher than the weight of the adjustment error. , , , This represents the actual adjustment amount for the i-th sample; , , , This represents the corresponding adjustment amount predicted by the model.

[0130] In the training parameter settings, the Ranger optimizer can be selected because it converges quickly, trains rapidly, and produces relatively accurate results, achieving stable performance without requiring a long iteration period. Initial learning rate. =1.8e-5, mini-batch=48, adaptive early stopping enabled, stop if the validation set modulo-locked prediction accuracy does not improve for 18 consecutive epochs.

[0131] The dual-pulse-width collaborative prediction model provided in this application can control priority to ensure no mode-locking occurs, and then precisely adjust the pulse parameters. The attention layer automatically focuses on the parameters that have the greatest impact on mode-locking, such as grating pair spacing deviation and stretching amount; the GELU activation function can capture subtle correlations between parameters, such as the effect of small-range stretching changes on wavelength; the weighted loss function can control mode-locking stability, and the penalty for mode-locking errors is 5 times that for adjustment errors, preventing the model from losing lock in order to match the pulse width.

[0132] Step S7: Optimize the dual-pulse-width collaborative prediction model using the Bayesian optimization algorithm.

[0133] Step S7 may include steps S71 to S74.

[0134] Step S71: Select a gradient boosting tree as the surrogate model and construct an objective function; wherein the objective function includes a first objective function, a second objective function, a third objective function and a fourth objective function. The first objective function is used to maximize mode-locking stability, the second objective function is used to minimize the pulse width error of the first laser, the third objective function is used to minimize the pulse width error of the second laser, and the fourth objective function is used to minimize the first center wavelength error.

[0135] By employing the Bayesian optimization algorithm to optimize the dual-pulse-width collaborative prediction model, the limitations of single-objective optimization can be overcome. Simultaneously, it achieves the collaborative objectives of stable mode-locking, compliant pulse width, accurate wavelength, and hardware security, and the objective priority can be dynamically adjusted.

[0136] Gradient Boosting Tree (XGBoost) is chosen as the surrogate model, and the objective function is... include:

[0137] (11)

[0138] Wherein, the first objective function The second objective function is used to maximize mode-lock stability. The third objective function is used to minimize the pulse width error of the first laser. The fourth objective function is used to minimize the pulse width error of the second laser. This is used to minimize the error of the first center wavelength.

[0139] Step S72: Construct the constraint function; in the constraint function, the weight values ​​corresponding to different mode-locking states are different.

[0140] A priority weighting system is introduced through constraint functions to construct a dynamic constraint system, which dynamically adjusts the constraint strength according to the current mode-locking state. include:

[0141] (12)

[0142] in, For mode-locking constraint weights, =5.0 indicates that the lock is lost. =1.0 indicates that the mode-locking is stable. - Other constraint weights are set to 1.0. The constraint function is defined in the same way as in the previous embodiment, including wavelength, pulse width, and hardware security constraints.

[0143] Step S73: Construct a multi-objective expectation improvement acquisition function that integrates target priorities; in the multi-objective expectation improvement acquisition function, the target priority coefficients are different for different mode-locking states.

[0144] Design a priority-based constraint multi-objective expectation improvement (P-CMEI) acquisition function that integrates objective priorities and constraint satisfaction probabilities. include:

[0145] (13)

[0146] in, The target priority coefficient is the priority coefficient of the first target when the lock is lost. =0.6, the priority coefficient of the second target Priority coefficient of the fourth target All are 0.15; when mode-locking is stable, the priority coefficient of the first target is... =0.3, the priority coefficient of the second target Priority coefficient of the third target Both are 0.25, the priority coefficient for the fourth objective. =0.2; The expected improvement for the k-th objective; The probability of satisfying dynamic constraints is used. By optimizing the output of the optimal adjustment value, multi-objective collaborative optimization is achieved.

[0147] Step S74: Improve the acquisition function and optimize the dual-pulse width collaborative prediction model based on the objective function, constraint function and multi-objective expectation.

[0148] The optimized dual-pulse-width collaborative prediction model can dynamically adjust priorities, ensuring the synergy of mode-locking stability, pulse width accuracy, and wavelength accuracy, achieving the coordinated goals of mode-locking stability and pulse width adjustment. Dynamic constraint weights can intelligently adjust their priorities. If mode-locking is currently lost, the weight for restoring mode-locking is increased, relaxing the accuracy requirements for pulse width or wavelength; if mode-locking is currently stable, the focus is on optimizing pulse parameters. The improved acquisition function prioritizes methods with a high probability of mode-locking and pulse parameters close to the target, controlling the coordination between pulse width adjustment and mode-locking state, ultimately achieving a deviation of less than 5% between the target value and the actual output value.

[0149] The control method for the intelligent control anti-lockout cooperative output ultrafast laser system provided in this application embodiment may further include step S8.

[0150] Step S8: Use a dual-pulse-width collaborative prediction model to control the intelligent modulation anti-lockout collaborative output ultrafast laser system.

[0151] In step S8, while controlling the intelligent control anti-lockout cooperative output ultrafast laser system to output the first laser and the second laser, a stable mode-locked state is maintained.

[0152] Based on the principle of prioritizing mode-lock stability, the control method for the intelligent control and anti-lock-loss collaborative output ultrafast laser system provided in this application embodiment can control the intelligent control and anti-lock-loss collaborative output ultrafast laser system to execute step-by-step adjustment and emergency mechanisms, ensuring that the adjustment process is safe and controllable. First, the mode-lock status is determined. If the current mode is lost, the first displacement stage moves at a speed v. Lg1 =5μm / ms, revert to the most recent stable grating pair spacing historical value, while briefly reducing the pump power by 10% to reduce the intracavity gain to assist mode-lock recovery; then adjust ,according to With λ c The corresponding relationship is used to calibrate the center wavelength to... ±1nm is used to avoid wavelength deviation indirectly affecting mode-locking stability; then ΔLg1 is adjusted, pausing for 2ms after every 5μm adjustment, and the signal-to-noise ratio (SNR) is detected simultaneously. If the SNR < 50dB, it is immediately reversed by 3μm to prevent dispersion imbalance from causing mode-locking failure; finally, the following adjustments are made sequentially. After each adjustment of ΔD3, pause for 2ms to collect pulse width data in real time, ensuring that the pulse width matches the target value. If the output power fluctuation is >3% or the SNR is <50dB, restart the optimization process to achieve dynamic stability.

[0153] The results of specific implementation examples are shown in Table 1 below:

[0154] Table 1. Center Wavelength vs. Pulse Width Comparison Table

[0155] ;

[0156] Existing technologies lack robust mechanisms for predicting and responding to mode-lock failure, making them susceptible to mode-lock imbalance due to environmental interference and parameter adjustments. The intelligent control method for an anti-lock failure collaborative output ultrafast laser system provided in this application integrates anti-lock failure measures throughout the entire process: During model training, a weighted loss function assigns a training priority five times that of pulse width adjustment to the mode-locked state; during optimization, dynamic constraint multi-objective Bayesian optimization is employed, automatically increasing the weight of mode-lock constraints upon loss of lock; during execution, a step-by-step strategy involving lock-lock backoff, wavelength calibration, dispersion optimization, and pulse width adjustment is implemented, coupled with real-time monitoring at 10ms intervals, such as monitoring power fluctuations, SNR, and pulse width deviation. Upon the appearance of signs of lock failure, emergency actions such as grating spacing backoff and pump power fine-tuning are immediately triggered. This mechanism ensures that the system maintains stable mode-locked pulse output even under environmental interference such as temperature fluctuations and vibrations, solving the core problem of easy lock failure in traditional systems during long-term operation.

[0157] During the control process, firstly, the main control board controls the first displacement stage, which can adjust the grating pair spacing with high precision. Compared with manual adjustment of the grating pair spacing, the system has higher adjustment accuracy and stability. Secondly, combined with the target pulse width input from the host computer, the base module can be intelligently controlled. By applying precise tension to the optical fiber, higher precision and more controllable center wavelength tuning can be achieved, thereby directly and accurately outputting the required pulse width. This realizes intelligent operation and predictable results, and also improves the system's filtering performance and wavelength positioning accuracy.

[0158] The control method of this intelligent control anti-lockout collaborative output ultrafast laser system does not rely on an electrical signal time base, and can directly achieve ultrashort pulse output at the picosecond and femtosecond levels. The pulse width adjustment range is wider and better suited to the core application requirements of ultrafast lasers. A grating is used to separate the incident light wavelength, and wavelength selection is achieved by adjusting the grating angle. However, the efficiency of the diffraction grating is strongly correlated with the angle, and changes in the angle will significantly affect the overall system efficiency. In this application, the diffraction grating angle is fixed at the position of maximum efficiency, and the pulse width is adjusted only by controlling the spacing between the grating pairs to change the negative dispersion value they provide. This ensures the stability of the system output efficiency and improves the accuracy of pulse width adjustment through precise dispersion control.

[0159] Figure 5 This is the second flowchart illustrating a control method for an intelligent control anti-lockout collaborative output ultrafast laser system provided in this application embodiment.

[0160] See Figure 5 As shown, in a specific implementation, the first laser output by the intelligent control anti-lockout collaborative output ultrafast laser system can be a femtosecond laser, and the second laser can be a picosecond laser.

[0161] The control method for the intelligent control anti-lockout collaborative output ultrafast laser system can be achieved by the following steps S01 to S06.

[0162] Step S01: Obtain the basic parameters of the dispersive filter component: the first grating pair spacing set [Lg 11 ,Lg 12 , ..., Lg 1i The set of stretch amounts of the base module is ΔX = [ΔX1, ΔX2, ..., ΔX]. i ], and the set of center wavelengths λ corresponding to the stretching amount. c =[λ1, λ2, ..., λ i This yields the quantized correspondence between the stretching amount and the center wavelength.

[0163] The correspondence is as follows:

[0164] .

[0165] This step can be referred to step S1 of the aforementioned embodiment.

[0166] Step S02: Establish a dual-pulse-width collaborative prediction model, through... The grating pair spacing and stretching are linked, with the stretching amount constrained to ≤3mm and the total adjustment of the grating pair spacing to ≤1cm, maintaining a constant optical path difference between the two arms to ensure filtering stability.

[0167] Typically, dispersion control and spectral filtering are performed independently, which can easily lead to net dispersion imbalance within the cavity, pulse broadening, or filtering failure. This application establishes a collaborative adjustment model for the dispersion filtering component, deeply binding dispersion compensation and spectral filtering. This collaborative design ensures the accuracy of dispersion compensation while avoiding distortion of filtering characteristics due to independent adjustment, significantly improving the stability of pulse output.

[0168] Dual-pulse coordinated output + anti-lockout dual protection: For the first time, dual-pulse coordinated control is combined with the anti-lockout mechanism for excessive movement of the displacement stage. Through safety range calibration, adjustment amount limitation, real-time lockout monitoring and back-off mechanism, it ensures that the movement of the displacement stage of the dispersion management module does not exceed the mode-locking allowable range, thus solving the lockout problem caused by excessive movement of components in traditional lasers.

[0169] Step S03: Collect the historical operating parameters of the second grating pair in the first pulse width adjustment component and the adjustable fiber stretcher in the second pulse width adjustment component, clarify the dispersion constraints, and adapt to the adjustable requirements of femtosecond and picosecond pulse widths.

[0170] Step S04: Acquire system running data synchronously at 1kHz, remove abnormal samples such as lock loss, construct a 10-dimensional feature vector and perform standardization processing, and split it into training set and test set according to the ratio.

[0171] Steps S02-S04 above can refer to steps S2-S5 of the aforementioned embodiment.

[0172] Step S05: Train a nonlinear prediction model that incorporates an attention mechanism. Based on the input feature vector, ensure the mode-locking priority and output precise matching parameters. .

[0173] This step can be referred to step S6 of the aforementioned embodiment.

[0174] Step S06: Employ a multi-objective Bayesian optimization algorithm to dynamically adjust the objective priorities and output the optimal adjustment value to achieve femtosecond τ. fs With picosecond τ ps Precise pulse width matching and coordinated stable adjustable output.

[0175] This step can be referred to as steps S7-S8 in the aforementioned embodiment.

[0176] Traditional mode-locked lasers are limited by the fixed bandwidth of their filtering devices, making it difficult to flexibly switch pulse types and resulting in a narrow pulse width adjustment range. This application's embodiment adjusts the filter bandwidth by 3dB through stretching, and, combined with a dual pulse width adjustment module, ultimately achieves femtosecond pulse output of 127fs-326fs and picosecond pulse output of 6ps-150ps, with a center wavelength covering an adjustable range of 1023.3nm-1039.5nm. Compared to existing multi-pulse laser systems, this design is more adaptable to the pulse requirements of different scenarios such as ultra-precision machining and microscopic detection, solving the problem of the limited pulse characteristics of traditional systems.

[0177] It should be noted that, upon considering the specification and practicing the application disclosed herein, those skilled in the art will readily conceive of other embodiments of this application. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0178] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The true scope is indicated by this application.

Claims

1. A smart control anti-lockout cooperative output ultrafast laser system, characterized in that, include: The pump module is configured to transmit pump light; A first beam splitter is disposed in the optical path of the pump light, and the first input terminal of the first beam splitter is connected to the pump module; A dispersion filter component is disposed on the side of the first beam splitter away from the pump module. The input end of the dispersion filter component is connected to the first output end of the first beam splitter. The dispersion filter component is configured to perform dispersion compensation to output laser light. The pulse width adjustment component includes a first pulse width adjustment component and a second pulse width adjustment component, wherein the first pulse width adjustment component and the second pulse width adjustment component are respectively connected to the dispersive filter component; The first pulse width modulation component is configured to perform dispersion compensation on the laser using a first pulse width modulation mechanism to output a first laser; the second pulse width modulation component is configured to perform dispersion compensation on the laser using a second pulse width modulation mechanism to output a second laser. The first pulse width adjustment mechanism is different from the second pulse width adjustment mechanism, and the pulse widths of the first laser and the second laser are different. The dispersion filtering component includes a second beam splitter and a first grating pair module; the first input terminal of the second beam splitter is connected to the first output terminal of the first beam splitter, and the first output terminal of the second beam splitter is connected to the first grating pair module; the first grating pair module is configured to receive the laser and perform dispersion compensation on the laser. The dispersion filtering component further includes a third beam splitter and a base module; the first input end of the third beam splitter is connected to the first grating pair module; the second output end of the second beam splitter is connected to the second input end of the third beam splitter, and the connecting optical fiber between the second output end of the second beam splitter and the second input end of the third beam splitter is fixed on the base module. The dispersion filtering component is also connected to the second input terminal of the first beam splitter, and the second pulse width adjustment component is connected to the second output terminal of the first beam splitter.

2. The intelligent control anti-lockout cooperative output ultrafast laser system according to claim 1, characterized in that, The optical path between the first output end of the second beam splitter and the first input end of the third beam splitter is the first optical path, and the optical path between the second output end of the second beam splitter and the connecting optical fiber between the base modules is the second optical path; the first optical path and the second optical path are different to filter the laser.

3. The intelligent control anti-lockout cooperative output ultrafast laser system according to claim 2, characterized in that, The first pulse width adjustment component is connected to the dispersive filtering component, and the first pulse width adjustment component includes a third fiber collimator and a second grating pair module; The input end of the third fiber collimator is connected to the output end of the third beam splitter. The third fiber collimator is configured to collimate the laser and then direct it into the second grating pair module. The second grating pair module is configured to use the first pulse width adjustment mechanism to compensate for the dispersion value of the first fiber connection segment. The first fiber connection segment includes the connecting fiber between the third beam splitter and the third fiber collimator.

4. The intelligent control anti-lockout cooperative output ultrafast laser system according to claim 1, characterized in that, The second pulse width adjustment component includes a circulator and an adjustable fiber stretcher; the first port of the circulator is connected to the second output of the first beam splitter; the second port of the circulator is connected to the adjustable fiber stretcher; the intelligent control anti-lockout cooperative output ultrafast laser system also includes a fourth fiber collimator; the third port of the circulator is connected to the fourth fiber collimator. The adjustable fiber stretcher is configured to compensate for the dispersion value of the second fiber connection segment using the second pulse width adjustment mechanism. The second fiber connection segment includes the connecting fiber between the first beam splitter and the fourth fiber collimator.

5. The intelligent control anti-lockout cooperative output ultrafast laser system according to claim 2, characterized in that, The first grating pair module includes a first grating pair and a first displacement stage; the first grating in the first grating pair is disposed on the first displacement stage, and the first displacement stage is configured to drive the first grating to move along the normal direction of the first grating to adjust the first grating pair spacing of the first grating pair; the first grating pair module is also configured to perform dispersion compensation based on the first grating pair spacing.

6. A control method for an intelligent control anti-lockout cooperative output ultrafast laser system, characterized in that, In the intelligent control anti-lock-breakage cooperative output ultrafast laser system applied as described in any one of claims 1-5, the control method of the intelligent control anti-lock-breakage cooperative output ultrafast laser system includes: Based on the first grating pair spacing set in the dispersion filter component, the first stretching amount set of the base module in the dispersion filter component, and the first center wavelength set in the dispersion filter component, the correspondence between the stretching amount and the center wavelength of the base module is determined; the first center wavelength in the first center wavelength set corresponds one-to-one with the first stretching amount in the first stretching amount set. The stretching amount is used to compensate for the optical path difference in the dispersive filter component, thereby controlling the optical path difference to be constant. Based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component, the dispersion value of the first optical fiber connection segment is compensated. Based on the second pulse width set of the second pulse width adjustment component and the dispersion value set of the adjustable fiber stretcher in the second pulse width adjustment component, the dispersion value of the second fiber connection segment is compensated. Establish a dataset; the dataset includes a multidimensional feature vector, which includes the first target center wavelength, the first target pulse width, the second target pulse width, the first measured center wavelength, the first measured pulse width, the second measured pulse width, the first grating spacing measured adjustment amount, the second grating spacing measured adjustment amount, the first measured stretching amount of the base module, and the measured dispersion value of the second pulse width adjustment component; The dataset is used to train a dual-pulse-width collaborative prediction model; the input of the trained dual-pulse-width collaborative prediction model is the multi-dimensional feature vector, and the output is the first grating pair spacing adjustment amount, the second grating pair spacing adjustment amount, the first stretching amount of the base module, the pump light power adjustment amount, and the dispersion value adjustment amount of the second pulse width adjustment component. The dual-pulse-width collaborative prediction model was optimized using a Bayesian optimization algorithm.

7. The control method for the intelligent control anti-lockout cooperative output ultrafast laser system according to claim 6, characterized in that, Based on the first grating pair spacing set in the dispersive filter component, the first stretching amount set of the base module in the dispersive filter component, and the first center wavelength set, the correspondence between the stretching amount and the center wavelength is determined, including: Within the stable mode-locked pump power range of the pump light, the set of the first grating pair spacing, the set of the first stretching amount, and the set of the first center wavelengths corresponding to the first stretching amount are collected in the first grating pair. The adjustment amount of the first grating pair spacing is determined based on the first grating pair spacing set; The correspondence between stretching amount and center wavelength is determined based on the first grating pair spacing set, the first center wavelength set, and the first stretching amount set; wherein, the absolute value of the maximum value of the first grating pair spacing adjustment amount is within a first preset range, the first stretching amount is within a second preset range, and the first preset range is different from the second preset range.

8. The control method for the intelligent control anti-lockout cooperative output ultrafast laser system according to claim 7, characterized in that, Based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component, the dispersion value of the first fiber connection segment is compensated, including: Based on the second grating pair spacing set and the corresponding first pulse width set in the first pulse width adjustment component, the negative dispersion value of the first pulse width adjustment component is determined; The dispersion value of the first optical fiber connection segment is compensated based on the negative dispersion value; the absolute value of the negative dispersion value is greater than or equal to the absolute value of the dispersion value of the first optical fiber connection segment.

9. The control method for the intelligent control anti-lockout cooperative output ultrafast laser system according to claim 8, characterized in that, The dual-pulse-width collaborative prediction model is trained using the dataset, including: A dual-pulse-width collaborative prediction model is constructed. The dual-pulse-width collaborative prediction model is a nonlinear prediction model that integrates an attention mechanism. The dual-pulse-width collaborative prediction model includes an input layer, an attention layer, a hidden layer, and an output layer connected in sequence. The dual-pulse width collaborative prediction model is trained by combining the dataset and the anti-lockout priority.

10. The control method for the intelligent control anti-lockout cooperative output ultrafast laser system according to claim 9, characterized in that, The dual-pulse-width collaborative prediction model is optimized using a Bayesian optimization algorithm, including: Gradient boosting tree is selected as the surrogate model to construct an objective function; wherein, the objective function includes a first objective function, a second objective function, a third objective function and a fourth objective function, the first objective function is used to maximize mode-locking stability, the second objective function is used to minimize the pulse width error of the first laser, the third objective function is used to minimize the pulse width error of the second laser, and the fourth objective function is used to minimize the first center wavelength error; Construct a constraint function; in the constraint function, the weight values ​​corresponding to different mode-locking states are different; A multi-objective expectation improved acquisition function is constructed that integrates target priorities; in the multi-objective expectation improved acquisition function, the target priority coefficients corresponding to different mode-locking states are different; The dual-pulse width collaborative prediction model is optimized based on the objective function, the constraint function, and the multi-objective expectation improved acquisition function.

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