Multi-mode four-wave mixing automatic mode locking device and method

Abstract

The invention discloses a multimode four-wave mixing automatic mode locking device and method. The device comprises an upper computer, an electric polarization controller, a space-time mode locking laser, an oscilloscope and a spectrograph. Wherein the upper computer is connected with the space-time mode-locked laser; the electric polarization controller is located in the space-time mode-locked laser; the input ends of the oscilloscope and the spectrograph are connected with the space-time mode-locked laser, and the output ends of the oscilloscope and the spectrograph are connected with the upper computer; the upper computer is used for outputting voltage to control the electric polarization controller, acquiring data of the oscilloscope and the spectrograph and executing a four-wave mixing automatic mode locking algorithm; and the electric polarization controller is used for receiving a voltage signal from the upper computer, regulating and controlling the polarization state and the optical fiber length of the space-time mode-locked laser, and changing energy coupling of different transverse modes in the space-time mode-locked laser. According to the invention, the four-wave mixing phenomenon is automatically detected, so that automatic mode locking of four-wave mixing can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of mode-locked lasers and automatic control, and in particular to a multi-mode four-wave mixing automatic mode-locking device and method. Background Art

[0002] Traditional mode-locked fiber lasers use single-mode fibers, while space-time mode-locked fiber lasers use multimode fibers, which can transmit multiple transverse modes. Transverse modes refer to different spatial modes of the light field, that is, the intensity distribution on the cross section of the laser beam. Space-time mode locking refers to the synchronous locking of the longitudinal mode and the transverse mode, that is, the synchronous locking of time and space. By fusing multimode fiber with single-mode / few-mode fiber, or by staggered fusing between multimode fibers, a multimode interference filtering effect can be generated to filter the wavelength of the laser pulse. By adjusting the polarization controller on the multimode fiber, the multimode interference filtering effect can be used to generate a variety of pulse phenomena, such as wavelength tuning, multi-wavelength, four-wave mixing, etc. Among them, the polarization controller is a device used to adjust the state of the laser.

[0003] Traditional laser mode locking requires researchers to manually debug the polarization controller and observe the phenomena of the detection instrument to achieve mode-locked pulses, which consumes a lot of time and human resources. Automatic mode locking can control the electric polarization controller through a program, obtain the experimental data of the detection instrument, and score the experimental data through an evaluation function. The program uses an intelligent algorithm (such as a genetic algorithm) based on the score to determine the next adjustment of the electric polarization controller, thereby achieving intelligent mode locking and saving manpower and material resources. Among them, the evaluation function is a formula written according to the target phenomenon. Usually, the electric polarization controller needs to input a voltage value group, called an individual, which includes three voltage values, which control three components respectively.

[0004] At present, automatic mode locking is only applied to single-mode fiber mode-locked lasers, and there is no automatic mode locking for multi-mode fiber mode-locked lasers (time-space mode-locked lasers), and there is no application of automatic mode locking for four-wave mixing phenomenon. And when using traditional genetic algorithms to automatically mode-lock multi-mode fiber mode-locked lasers, it is easy to lock to individuals in the laser that occupy a wide range of voltage values ​​of the electric polarization controller, making the experimental phenomenon relatively single, which is not conducive to the tuning of automatic mode locking. Summary of the invention

[0005] The purpose of the present invention is to provide a multi-mode four-wave mixing automatic mode locking device and method, which overcomes the defect that the prior art cannot realize the automatic mode locking of four-wave mixing by identifying the four-wave mixing spectrum.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A multi-mode four-wave mixing automatic mode locking device comprises a host computer, an electric polarization controller, a time-space mode locking laser, an oscilloscope, and a spectrometer; wherein the electric polarization controller is located in the time-space mode locking laser; the host computer is connected to the electric polarization controller; the input end of the oscilloscope and the spectrometer is connected to the time-space mode locking laser, and the output end of the oscilloscope and the spectrometer is connected to the host computer;

[0008] The host computer is used to output voltage to control the electric polarization controller, obtain data from the oscilloscope and spectrometer, and execute the four-wave mixing automatic mode locking algorithm;

[0009] The electric polarization controller is used to receive the voltage signal from the host computer, adjust the polarization state and fiber length of the spatiotemporal mode-locked laser, and change the energy coupling of different transverse modes in the spatiotemporal mode-locked laser;

[0010] The spatiotemporal mode-locked laser is used to output mode-locked pulses of different phenomena under the control of an electric polarization controller, and the output laser is divided into two paths through an optical coupler and transmitted to an oscilloscope and a spectrometer respectively;

[0011] An oscilloscope, used to receive a time domain signal from the spatiotemporal mode-locked laser and output a time domain image and data of the laser;

[0012] The spectrometer is used to receive the spectrum signal from the spatiotemporal mode-locked laser and output the spectrum image and data of the laser.

[0013] A multi-mode four-wave mixing automatic mode locking method is applied to the multi-mode four-wave mixing automatic mode locking device, comprising the following steps:

[0014] S1, the host computer randomly selects a voltage value interval, selects an initial voltage value to control the electric polarization controller, and regulates the output state of the spatiotemporal mode-locked laser;

[0015] S2, the oscilloscope receives the laser signal output by the spatiotemporal mode-locked laser, and transmits the time domain signal of the optical signal to the host computer, which identifies the time domain signal and then realizes automatic mode-locking operation through a genetic algorithm;

[0016] S3, the spectrometer receives the laser signal output by the spatiotemporal mode-locked laser, and transmits the spectral image and data of the laser to the host computer, which calls the wavelength multiplexing analysis program of the spectrometer to determine whether the spectral information is four-wave mixing, and calculates the output state of the four-wave mixing;

[0017] S4, if the output state does not meet the preset target state, then change the voltage value interval and reselect the initial population until the four-wave mixing output state meets the preset target state;

[0018] S5. If the output state of the four-wave mixing meets the preset target state, the automatic mode locking of the multi-mode four-wave mixing is terminated.

[0019] Preferably, in S2, the host computer discriminates the time domain signal, and then realizes the automatic mode locking operation through the genetic algorithm, which specifically includes:

[0020] After the host computer obtains the time domain data of the oscilloscope, it performs peak detection and determines the peak with intensity greater than the specified threshold as a pulse, thereby obtaining the number of pulses. The average pulse amplitude and jitter are calculated by the peak amplitude of the pulse; the number of pulses, the average pulse amplitude and the jitter are weighted and scored, and the sum obtained is the time domain signal score of the laser output phenomenon at the voltage value. The closer to the mode-locked pulse state, the higher the score; the genetic algorithm will perform inheritance, crossover and mutation operations according to the time domain signal score until the output of the mode-locked pulse is achieved.

[0021] Preferably, in S2, the genetic algorithm used is a regional genetic algorithm, which divides the voltage value range controlling the electric polarization controller into several intervals, randomly selects one of the intervals to generate an initial population, and performs crossover, mutation and genetic operations of the genetic algorithm until mode-locked pulse output is achieved.

[0022] Preferably, in S3, the host computer calls the wavelength multiplexing analysis program of the spectrometer to determine whether the spectrum information is four-wave mixing, and calculates the output state of the four-wave mixing, which specifically includes:

[0023] The host computer calls the wavelength division multiplexing analysis program of the spectrometer to obtain the wavelength and level information of the spectrum peaks greater than the specified threshold in the spectrum; the wavelength intervals of adjacent spectrum peaks are calculated, and when three consecutive identical wavelength intervals appear, it is determined to be four-wave mixing; and the wavelengths of the corresponding spectrum peaks are extracted to form a four-wave mixing wavelength group, and then the number of wavelengths and wavelength intervals of four-wave mixing are obtained, and the wavelengths in the four-wave mixing wavelength group are averaged to obtain the central wavelength.

[0024] Preferably, in S4-S5, different operations are performed according to whether the four-wave mixing output state meets the preset target state, specifically including:

[0025] The upper computer determines whether it is four-wave mixing by distinguishing the four-wave mixing spectrum, and calculates whether the number of wavelengths, wavelength interval and central wavelength of the four-wave mixing meet the preset target state. If it is not four-wave mixing that meets the target conditions, the patience value is reduced by 1 and the search is restarted; when the patience value is 0, the next voltage value interval is changed for operation; if it meets the preset target state, the automatic locking of multi-mode four-wave mixing is terminated.

[0026] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, a multi-mode four-wave mixing automatic mode locking method as described above is implemented.

[0027] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0028] The multi-mode four-wave mixing automatic mode locking device and method provided by the present invention can automatically detect the four-wave mixing phenomenon and realize the automatic mode locking of the four-wave mixing; by identifying the four-wave mixing spectrum, the defect that the prior art cannot realize the automatic mode locking of the four-wave mixing is overcome. Through the regional genetic algorithm proposed by the present invention, the state of the laser can be searched in a larger range by using the multi-mode interference filtering effect, and the target four-wave mixing state can be searched more easily; more experimental phenomena of the spatiotemporal mode-locked laser can be searched, which is conducive to the automatic mode locking of the four-wave mixing of different preset target states. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0030] Figure 1 A schematic diagram of a multi-mode four-wave mixing automatic mode locking device provided by the present invention;

[0031] Figure 2 A flow chart of a multi-mode four-wave mixing automatic mode locking method provided by the present invention;

[0032] Figure 3 This is the four-wave mixing spectrum distribution diagram identified by the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1As shown, a multi-mode four-wave mixing automatic mode locking device provided by the present invention includes a host computer, an electric polarization controller, a time-space mode locking laser, an oscilloscope, and a spectrometer; wherein the electric polarization controller is located in the time-space mode locking laser; the host computer is connected to the electric polarization controller; the input end of the oscilloscope and the spectrometer is connected to the time-space mode locking laser, and the output end of the oscilloscope and the spectrometer is connected to the host computer;

[0036] The host computer is used to output voltage to control the electric polarization controller, obtain data from the oscilloscope and spectrometer, and execute the four-wave mixing automatic mode locking algorithm;

[0037] The electric polarization controller is used to receive the voltage signal from the host computer, adjust the polarization state and fiber length of the space-time mode-locked laser, and change the energy coupling of different transverse modes in the space-time mode-locked laser; under different voltage input values, the polarization state of the laser in the laser is regulated, the fiber length is fine-tuned, the energy coupling of different transverse modes changes, and the laser will output different phenomena.

[0038] The spatiotemporal mode-locked laser is used to achieve mode-locked pulse output of different phenomena under the control of the electric polarization controller. The output laser is divided into two paths through an optical coupler, one is received by an oscilloscope, and the other is received by a spectrometer. The experimental phenomena include but are not limited to single-wavelength, multi-wavelength mode-locked pulses, and four-wave mixing mode-locked pulses with different numbers of wavelengths, center wavelengths, and wavelength intervals;

[0039] An oscilloscope, used to receive a time domain signal from the spatiotemporal mode-locked laser and output a time domain image and data of the laser;

[0040] The spectrometer is used to receive the spectrum signal from the spatiotemporal mode-locked laser and output the spectrum image and data of the laser.

[0041] like Figure 2 As shown, a multi-mode four-wave mixing automatic mode locking method provided by the present invention is applied to the above-mentioned multi-mode four-wave mixing automatic mode locking device, comprising the following steps:

[0042] S1, the host computer randomly selects a voltage value interval, selects an initial voltage value to control the electric polarization controller, and regulates the output state of the spatiotemporal mode-locked laser;

[0043] S2, the oscilloscope receives the laser signal output by the spatiotemporal mode-locked laser, and transmits the time domain image and data of the laser to the host computer, which identifies the time domain signal and then realizes automatic mode-locking operation through genetic algorithm;

[0044] S3, the spectrometer receives the laser signal output by the spatiotemporal mode-locked laser, and transmits the spectral image and data of the laser to the host computer, which calls the wavelength multiplexing analysis program of the spectrometer to determine whether the spectral information is four-wave mixing, and calculates the output state of the four-wave mixing;

[0045] S4, if the output state does not meet the preset target state, then change the voltage value interval and reselect the initial population until the four-wave mixing output state meets the preset target state;

[0046] S5. If the output state of the four-wave mixing meets the preset target state, the automatic mode locking of the multi-mode four-wave mixing is terminated.

[0047] Furthermore, in S2, the host computer determines the time domain signal and then implements the automatic mode locking operation through the genetic algorithm, which specifically includes:

[0048] After the host computer obtains the time domain data of the oscilloscope, it performs peak detection and determines the peak with intensity greater than the specified threshold as a pulse, thereby obtaining the number of pulses. The average pulse amplitude and jitter are calculated by the peak amplitude of the pulse; the number of pulses, the average pulse amplitude and the jitter are weighted and scored, and the sum obtained is the time domain signal score of the laser output phenomenon at the voltage value. The closer to the mode-locked pulse state, the higher the score; the genetic algorithm will perform inheritance, crossover and mutation operations according to the time domain signal score until the output of the mode-locked pulse is achieved.

[0049] Furthermore, in S2, the genetic algorithm used is a regional genetic algorithm, which divides the voltage value range controlling the electric polarization controller into several intervals, randomly selects one of the intervals to generate an initial population, and performs crossover, mutation and genetic operations of the genetic algorithm until the mode-locked pulse output is achieved.

[0050] Furthermore, in S3, the host computer calls the wavelength multiplexing analysis program of the spectrometer to determine whether the spectrum information is four-wave mixing, and calculates the output state of the four-wave mixing, which specifically includes:

[0051] The host computer calls the wavelength division multiplexing analysis program of the spectrometer to obtain the wavelength and level information of the spectrum peaks greater than the specified threshold in the spectrum; the wavelength intervals of adjacent spectrum peaks are calculated, and when three consecutive identical wavelength intervals appear, it is determined to be four-wave mixing. Figure 3 As shown; and the wavelengths of the corresponding spectrum peaks are extracted to form a four-wave mixing wavelength group, thereby obtaining the number of wavelengths and wavelength intervals of four-wave mixing, and averaging the wavelengths in the four-wave mixing wavelength group to obtain the central wavelength.

[0052] Further, in S4-S5, different operations are performed according to whether the four-wave mixing output state meets the preset target state, including:

[0053] The upper computer determines whether it is four-wave mixing by distinguishing the four-wave mixing spectrum, and calculates whether the number of wavelengths, wavelength interval and central wavelength of the four-wave mixing meet the preset target state. If it is not four-wave mixing that meets the target conditions, the patience value is reduced by 1 and the search is restarted; when the patience value is 0, the next voltage value interval is changed for operation; if it meets the preset target state, the automatic locking of multi-mode four-wave mixing is terminated.

[0054] Specifically, the wavelength number, center wavelength, and wavelength interval information of the four-wave mixing are compared with the preset target state, wherein the comparison of the center wavelength and the wavelength interval allows a certain error, and the accuracy of the error can be adjusted, for example, the center wavelength can have an error of 0.5nm, and the wavelength interval can have an error of 0.1nm. If the output state does not meet the preset target conditions, the regional genetic algorithm will change the voltage value interval and search for other different output phenomena of the laser.

[0055] The present invention improves the traditional genetic algorithm by dividing the population of the genetic algorithm into several intervals. Due to the multi-mode interference filtering effect, individuals in different intervals will produce experimental phenomena with large differences, thereby expanding the search range for laser phenomena. The voltage value range for controlling the electric polarization controller is divided into several intervals; for example, the voltage value range for controlling the electric polarization controller is (0-10V). Since the electric polarization controller has three control components, the three voltage values ​​are grouped into (0-10V, 0-10V, 0-10V). This voltage value group can be divided into 8 intervals, namely (0-5V, 0-5V, 0-5V), (0-5V, 0-5V, 5V-10V), (0-5V, 5V-10V, 5V-10V)...(5-10V, 5-10V, 5-10V).

[0056] Different from the traditional genetic algorithm, which selects the initial population (i.e., voltage value) in the entire range, the selection of the initial population of the regional genetic algorithm will be carried out in a certain interval. Due to the multi-mode interference filtering effect, the laser will produce experimental phenomena with large differences under the voltage control of different intervals. First, one of the intervals is randomly selected, and several voltage value groups (for example, 10) are randomly generated, which are sequentially input into the electric polarization controller to regulate the spatiotemporal mode-locked laser. Then, the time domain signal of the mode-locked pulse is discriminated according to the data of the oscilloscope, the time domain score is obtained, and the crossover, mutation and genetic operations of the genetic algorithm are performed until the output of the mode-locked pulse is achieved. Next, the four-wave mixing is discriminated by the data of the spectrometer to determine whether it is four-wave mixing, and the number of wavelengths, wavelength intervals and central wavelengths of the four-wave mixing are calculated to determine whether they meet the preset target state. If not, the patience value is reduced by 1, and the patience value is the number of search attempts in this interval, for example, set to 2. When the patience value is 0, the voltage value interval is changed, the initial population is selected again, and the operation of the genetic algorithm is continued until the laser output meets the preset target state.

[0057] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, a multi-mode four-wave mixing automatic mode locking method as described above is implemented.

[0058] In a specific embodiment, first, the spatiotemporal mode-locked laser is connected to the pump source to generate laser output. The host computer randomly selects a voltage value interval and selects a voltage value to control the electric polarization controller. Under different voltage value inputs, the polarization state of the laser in the laser is regulated, the fiber length is fine-tuned, the energy coupling of different transverse modes changes, and different phenomena are output due to the multi-mode interference filtering effect. The output of the laser is divided into two paths and transmitted to the oscilloscope and the spectrometer respectively. The oscilloscope outputs the laser time domain signal and transmits it to the host computer. The host computer scores the three information of the number of pulses, the average amplitude of the pulses, and the jitter of the time domain signal. The closer to the mode-locked pulse state, the higher the score. Then, the host computer performs genetic, crossover and mutation operations of the genetic algorithm according to the time domain signal score until the mode-locked pulse output is achieved. Then, the spectrometer outputs the laser spectrum signal and transmits it to the host computer. The host computer calls the wavelength multiplexing analysis program of the spectrometer to identify four-wave mixing. When the spectrum wavelength has three consecutive identical wavelength intervals, it is determined to be four-wave mixing, and the number of wavelengths, wavelength intervals and center wavelength information of the four-wave mixing are calculated. If the output state does not meet the preset target state, the patience value is reduced. When the patience value is zero, the voltage value interval is changed to search for other output states of the laser. If the output state meets the preset target state, the automatic mode locking of the multi-mode four-wave mixing is terminated.

[0059] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0060] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A multi-mode four-wave mixing automatic mode locking device, characterized in that: It includes a host computer, an electric polarization controller, a spatiotemporal mode-locked laser, an oscilloscope, and a spectrometer; wherein the electric polarization controller is located in the spatiotemporal mode-locked laser; the host computer is connected to the electric polarization controller; the input end of the oscilloscope and the spectrometer is connected to the spatiotemporal mode-locked laser, and the output end of the oscilloscope and the spectrometer is connected to the host computer; The host computer is used to output voltage to control the electric polarization controller, obtain data from the oscilloscope and spectrometer, and execute a four-wave mixing automatic mode locking algorithm; The electric polarization controller is used to receive a voltage signal from a host computer, adjust the polarization state and fiber length of the space-time mode-locked laser, and change the energy coupling of different transverse modes in the space-time mode-locked laser; The spatiotemporal mode-locked laser is used to output mode-locked pulses of different phenomena under the control of the electric polarization controller, and the output laser is divided into two paths through an optical coupler and transmitted to an oscilloscope and a spectrometer respectively; The oscilloscope is used to receive the time domain signal from the spatiotemporal mode-locked laser and output the time domain image and data of the laser; The spectrometer is used to receive the spectrum signal from the spatiotemporal mode-locked laser and output the spectrum image and data of the laser.

2. A multi-mode four-wave mixing automatic mode locking method, applied to the multi-mode four-wave mixing automatic mode locking device according to claim 1, characterized in that: The following steps are involved: S1, the host computer randomly selects a voltage value interval, selects an initial voltage value to control the electric polarization controller, and adjusts the output state of the spatiotemporal mode-locked laser; S2, the oscilloscope receives the laser signal output by the spatiotemporal mode-locked laser, and transmits the time domain image and data of the laser to the host computer, which identifies the time domain signal and then realizes automatic mode-locking operation through a genetic algorithm; S3, the spectrometer receives the laser signal output by the spatiotemporal mode-locked laser, and transmits the spectrum image and data of the laser to the host computer, which calls the wavelength multiplexing analysis program of the spectrometer to determine whether the spectrum information is four-wave mixing, and calculates the output state of the four-wave mixing; S4, if the output state does not meet the preset target state, then change the voltage value interval and reselect the initial population until the four-wave mixing output state meets the preset target state; S5. If the output state of the four-wave mixing meets the preset target state, the automatic mode locking of the multi-mode four-wave mixing is terminated.

3. A multi-mode four-wave mixing automatic mode locking method according to claim 2, characterized in that: In S2, the host computer discriminates the time domain signal and then implements the automatic mode locking operation through the genetic algorithm, which specifically includes: After the host computer obtains the time domain data of the oscilloscope, it performs peak detection and determines the peak with intensity greater than the specified threshold as a pulse, thereby obtaining the number of pulses. The average pulse amplitude and jitter are calculated by the peak amplitude of the pulse; the number of pulses, the average pulse amplitude and the jitter are weighted and scored, and the sum obtained is the time domain signal score of the laser output phenomenon at the voltage value. The closer to the mode-locked pulse state, the higher the score; the genetic algorithm will perform inheritance, crossover and mutation operations according to the time domain signal score until the output of the mode-locked pulse is achieved.

4. A multi-mode four-wave mixing automatic mode locking method according to claim 3, characterized in that: The genetic algorithm used in S2 is a regional genetic algorithm, which divides the voltage value range of the electric polarization controller into several intervals, randomly selects one of the intervals to generate an initial population, and performs crossover, mutation and genetic operations of the genetic algorithm until the mode-locked pulse output is achieved.

5. The multi-mode four-wave mixing automatic mode locking method according to claim 1, characterized in that: In S3, the host computer calls the wavelength multiplexing analysis program of the spectrometer to determine whether the spectrum information is four-wave mixing, and calculates the output state of the four-wave mixing, which specifically includes: The host computer calls the wavelength division multiplexing analysis program of the spectrometer to obtain the wavelength and level information of the spectrum peaks greater than the specified threshold in the spectrum; the wavelength intervals of adjacent spectrum peaks are calculated, and when three consecutive identical wavelength intervals appear, it is determined to be four-wave mixing; the wavelengths of the corresponding spectrum peaks are extracted to form a four-wave mixing wavelength group, and then the number of wavelengths and wavelength intervals of four-wave mixing are obtained, and the wavelengths in the four-wave mixing wavelength group are averaged to obtain the central wavelength.

6. A multi-mode four-wave mixing automatic mode locking method according to claim 4, characterized in that: In S4-S5, different operations are performed according to whether the output state of the four-wave mixing meets the preset target state, specifically including: The upper computer determines whether it is four-wave mixing by distinguishing the four-wave mixing spectrum, and calculates whether the number of wavelengths, wavelength interval and central wavelength of the four-wave mixing meet the preset target state. If it is not four-wave mixing that meets the target conditions, the patience value is reduced by 1 and the search is restarted; when the patience value is 0, the next voltage value interval is changed for operation; if it meets the preset target state, the automatic locking of multi-mode four-wave mixing is terminated.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, a multi-mode four-wave mixing automatic mode locking method as claimed in any one of claims 2 to 6 is implemented.

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