Laser phase modulation spectrum automatic screening method, device, equipment, medium and product
By detecting the returned light value in the laser and using a fixed current value to filter out spectral shapes below a threshold, the problems of laser component damage and long filtering time are solved, and efficient spectral shape filtering is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LASER FUSION RES CENT CHINA ACAD OF ENG PHYSICS
- Filing Date
- 2026-04-27
- Publication Date
- 2026-07-10
AI Technical Summary
Existing technologies make it difficult to accurately measure the output spectrum of phase modulation seed sources, and laser components are easily damaged during the screening process, which also takes a long time.
By obtaining the return light value under the initial spectrum, the differential return light value is selected as the set current value. The spectrum is screened using the fixed current value, the laser output power is reduced, and the spectrum below the set threshold is automatically screened as the preliminary screening result. Finally, the spectrum with the highest driving current in the self-pulse phenomenon is selected as the optimal spectrum.
This reduces the risk of laser device damage, shortens screening time, and enables preliminary screening of spectral patterns at lower output power.
Smart Images
Figure CN122360891A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of lasers, and in particular to a method, apparatus, device, medium, and product for automatic selection of laser phase modulation spectrum. Background Technology
[0002] As the output power of ultra-narrow linewidth fiber lasers increases, various nonlinear effects within the fiber cause the output power to enter the nonlinear region, exhibiting gain compression and thus limiting the maximum power output. Stimulated Brillouin scattering (SBS), due to its low threshold characteristics, becomes the primary limiting factor for power enhancement. Schemes utilizing phase modulation to broaden the seed source bandwidth offer advantages such as simple operation and high controllability, making them a research hotspot for suppressing the SBS effect in high-power fiber lasers.
[0003] Currently, spectrometers struggle to accurately measure the output spectral shape of phase-modulated seed sources. Current spectral shape methods, when using the laser reaching the SBS threshold as a criterion, risk damaging laser components such as optical fibers, isolators, and fiber optic patch cords from self-pulses in the laser output. Even if no damage occurs, it can still cause some degree of harm. Furthermore, the spectral shape selection stage requires significant time because each spectral shape necessitates applying a driving current until a self-pulse appears in the return light. Summary of the Invention
[0004] The purpose of this application is to provide a method, apparatus, equipment, medium, and product for automatic selection of laser phase modulation spectrum, which can reduce the laser output power and selection time for spectrum selection.
[0005] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides an automatic selection method for laser phase modulation spectrum, comprising: Obtain the return light values of the initial spectrum under different laser drive currents; Select the driving current corresponding to the difference in the returned light value among the different initial spectrum shapes as the set current value; The initial spectrum shape is changed and the return light value under the current spectrum shape is read; the return light value under the current spectrum shape is obtained by applying the driving current to the set current value; Select the spectral patterns whose returned light values are lower than the first set threshold under the current spectral pattern as the preliminary screening results; The preliminary screening result corresponding to the highest driving current value in the self-pulse phenomenon is selected as the optimal spectrum; the driving current value of the laser driving current is increased from the set current value until the spectrum self-pulse phenomenon in the preliminary screening result appears.
[0006] In one embodiment, the returned light value that shows a difference is a returned light value that is less than a set second set threshold.
[0007] Secondly, this application provides an automatic laser phase modulation spectrum screening device, comprising: the automatic laser phase modulation spectrum screening device applies the automatic laser phase modulation spectrum screening method, and the automatic laser phase modulation spectrum screening device comprises: a control module, a driving power supply, a laser, and a power meter connected in sequence; The power meter is used to observe the return light value in the laser and transmit the return light value to the control module; the drive current is used to drive the laser according to the drive current value. The control module is used for: Obtain the return light values of the initial spectrum under different laser drive currents; Select the driving current corresponding to the difference in the returned light value among the different initial spectrum shapes as the set current value; The initial spectrum shape is changed and the return light value under the current spectrum shape is read; the return light value under the current spectrum shape is obtained by applying the driving current to the set current value; Select the spectral patterns whose returned light values are lower than the first set threshold under the current spectral pattern as the preliminary screening results; The preliminary screening result corresponding to the highest driving current value in the self-pulse phenomenon is selected as the optimal spectrum; the driving current value of the laser driving current is increased from the set current value until the spectrum self-pulse phenomenon in the preliminary screening result appears.
[0008] In one embodiment, the power meter is connected to an optical fiber coupler in the laser.
[0009] In one embodiment, the power meter is connected to an isolator between the pre-amplification optical path and the main amplification optical path of the laser.
[0010] In one embodiment, the automatic laser phase modulation spectrum screening device further includes: a spectrometer; The spectrometer is used to measure the returned spectral shape of the laser.
[0011] In one embodiment, the control module is a computer.
[0012] Thirdly, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the automatic laser phase modulation spectrum screening method.
[0013] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the described automatic laser phase modulation spectrum selection method.
[0014] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the aforementioned automatic laser phase modulation spectrum selection method.
[0015] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application provides an automatic screening method, apparatus, device, medium, and product for laser phase modulation spectra. The method involves selecting a driving current corresponding to a difference in the returned light values among different initial spectral shapes as a set current value; changing the initial spectral shape and reading the returned light values under the current spectral shape; and selecting spectral shapes whose returned light values under the current spectral shape are below a first set threshold as preliminary screening results. Since the preliminary screening uses a set current value for driving, compared to the traditional method of directly increasing the laser output power until a self-pulse phenomenon occurs, the power used is lower, reducing damage to the laser device. Furthermore, the set current value is fixed, and automatic screening using a fixed value can significantly reduce the spectral screening time. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. 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 working principle of the seed source for a phase modulator. Figure 2 This is a schematic diagram of the spectrum screening principle. Figure 3 This is a graph showing the light readings returned from the spectrometer. Figure 4 This is a schematic diagram of an automatic laser phase modulation spectrum screening device. Figure 5 A schematic diagram illustrating the use of an isolator for return light detection; Figure 6 This is a schematic diagram of the automatic selection method for laser phase modulation spectrum.
[0018] Figure 7 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation
[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0020] Limited by the resolution of current commercial spectrometers, it is difficult for spectrometers to accurately measure the output spectral shape of phase modulation seed sources with linewidths of tens of gigabits. Therefore, the common approach is to test the linewidth of the overall envelope of the phase modulation seed source output spectral shape using a spectrometer. Currently, the quality of the seed source output spectral shape is determined by continuously increasing the output power of the fiber laser until a pulse appears in the returned light spectrum, or by converting the returned light into an electrical signal using a photodetector and detecting the pulse in the electrical signal using an oscilloscope, thus determining that the spectral shape has reached a threshold.
[0021] The working principle of the phase modulator seed source is as follows: Figure 1 As shown, the phase modulator drive waveform broadens a single-frequency seed source with a kHz-level linewidth to a GHz-level linewidth spectrum. Since the half-wave voltage of the phase modulator is generally above 1.5V, and the output amplitude of the signal generator is generally in the hundreds of mV range, the signal generator typically needs to be cascaded with an RF amplifier and a low-pass filter to drive the phase modulator, thus amplifying the electrical signal from the hundreds of mV range to the V range. The single-frequency seed source is broadened by the phase modulator to the high-flatness spectrum required by the laser. The shape, number of spectral lines, and intensity of the spectrum are controlled by the phase modulator drive waveform.
[0022] like Figure 2 As shown, the principle of spectral screening is: The laser consists of two parts: a phase-modulated seed source and a master oscillator amplification stage. After phase modulation and broadening, the broadened laser output enters the pre-amplification stage, with an output power of tens of W. The output light from the pre-amplification stage passes through an isolator (ISO), fiber coupler (FC), mode field adapter (MFA), and cladding optical filter (CPS) before entering the master amplification stage, thus amplifying the laser's power. A fiber coupler (FC) is connected between the laser's pre-amplification optical path and the master amplification optical path. The backlight monitor is connected to a spectrometer or converted into an electrical signal by a photodetector (PD) and connected to an oscilloscope. When the spectrometer (such as the Siyi Electronics 6362 series spectrometer) detects a pulse in the backlight spectrum or when the electrical signal measured by the oscilloscope shows a pulse, it indicates that the spectral shape has reached the SBS threshold on that laser.
[0023] exist Figure 3When the output power reaches 3050W, the spectrometer produces a pulse, indicating that the spectral shape is at the SBS threshold of 3050W for this laser.
[0024] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0025] This application proposes a method for automatically screening spectral shapes using returned light readings during the initial screening stage. The working principle is as follows: as the laser output power increases, different spectral shapes correspond to different returned light values. The pattern is as follows: when the laser output power is low, the returned light values corresponding to different spectral shapes are basically the same. When the output power increases to a certain level, differences appear in the returned light values corresponding to different spectral shapes. At this point, there is still some power before the laser produces a self-pulse. Therefore, the laser output power corresponding to the difference in returned light value can be used as a benchmark, and the spectral shapes can be screened by detecting the returned light values corresponding to different spectral shapes. Generally, at the same laser output power, a lower returned light value corresponds to a higher SBS threshold for that spectral shape, but this is not absolute. Therefore, after initially screening out several groups of spectral shapes corresponding to lower returned light values, the optimal spectral shape is selected using traditional methods.
[0026] In one exemplary embodiment, such as Figure 4 and Figure 6 As shown, an automatic laser phase modulation spectrum screening method is provided. This method is executed by a computer device, specifically by a terminal or server alone, or by both a terminal and a server. In the embodiments of this application, the method includes the following steps.
[0027] Step 101: Obtain the return light values of the initial spectrum under different laser drive currents.
[0028] Step 102: Select the driving current corresponding to the return light value that shows a difference among the return light values corresponding to different initial spectral shapes as the set current value. The return light value that shows a difference is a return light value that is less than the second set threshold (where a self-pulse phenomenon occurs).
[0029] In practical applications, the specific process of steps 101-102 is as follows: connect the returned light to the power meter, select 3-5 sets of spectral shapes, increase the laser driving current, observe the returned light value in the power meter, and find the laser output power and corresponding driving current when the returned light value of different spectral shapes changes significantly (the laser output power and driving current value correspond to a fixed driving current). When looking for significant changes in the returned light value, it can be done manually or through a computer program.
[0030] Step 103: Change the initial spectrum and read the return light value under the current spectrum; the return light value under the current spectrum is obtained by applying the driving current to the set current value.
[0031] In practical applications, step 103 involves establishing an automatic spectral selection platform, connecting the power meter to the PC, changing the spectral type, automatically loading the laser drive current value to the set current, and reading the power meter reading. The power meter reading is the returned optical value.
[0032] Step 104: Select the spectral patterns whose returned light values are lower than the first set threshold under the current spectral pattern as the preliminary screening results. The first set threshold is less than the second set threshold.
[0033] Step 105: Select the preliminary screening result corresponding to the highest drive current value in the self-pulse phenomenon as the optimal spectral shape; the drive current value of the laser drive current increases from the set current value until the self-pulse phenomenon of the spectral shape in the preliminary screening result appears. The self-pulse phenomenon refers to the appearance of a pulse in the spectral shape detected by the spectrometer, or the return light being converted into an electrical signal by a photodetector (PD) and connected to an oscilloscope. The oscilloscope detects a pulse in the electrical signal, thus the oscilloscope can be connected to a PC. When a pulse is detected in the electrical signal, it indicates the occurrence of the self-pulse phenomenon. In practical applications, because the self-pulse phenomenon can easily burn out the laser, it is generally used to simultaneously connect the return light to the spectrometer and convert it into an electrical signal via a PD and connect it to an oscilloscope. The oscilloscope is connected to the PC to detect the self-pulse phenomenon and automatically shuts off the drive current. Simultaneously, the engineer observes the spectrometer in real time, and when a self-pulse appears in the spectrometer, the drive current is shut off promptly. This is a method of simultaneous detection by both the computer and a human.
[0034] In practical applications, step 103 is repeated multiple times until all spectral shapes have been tested. Then, steps 104 and 105 are performed. Several groups of spectral shapes with lower returned light values are selected, and the returned light is connected to the spectrometer. A driving current is applied until the spectrometer produces a pulse, i.e., a self-pulse phenomenon. The spectral shape corresponding to the highest driving current is the optimal spectral shape.
[0035] By selecting the driving current corresponding to the differing return light values among different initial spectral shapes as the set current value; changing the initial spectral shape and reading the return light value under the current spectral shape; and selecting the spectral shape with return light values below a first set threshold as the preliminary screening result, preliminary screening is performed. Since the preliminary screening uses the set current value for driving, compared to the traditional method of directly increasing the laser output power for screening, the power used is lower, which can reduce damage to the laser device. Furthermore, the set current value is fixed, and automatic screening using a fixed value can significantly reduce the spectral shape screening time. The method provided in this application is applicable to the stage of preliminary screening of a large number of spectral shapes.
[0036] The method provided in this application can achieve preliminary screening of spectral patterns at relatively low laser output power, reducing damage to laser devices; in addition, since the driving current is a fixed value, an automatic spectral pattern screening platform can be established, significantly reducing the screening time.
[0037] In another exemplary embodiment, this application provides an automatic laser phase modulation spectrum screening device, which applies the aforementioned automatic laser phase modulation spectrum screening method. The automatic laser phase modulation spectrum screening device includes: a control module, a drive power supply, a laser, and a power meter connected in sequence. The control module is a PC, the drive power supply is a constant current source, such as the Juntao Technology TLB33A6KW480A, the laser is a phase modulation seed source and a laser master oscillation stage amplification structure, such as the JPT continuous narrow linewidth MOPA series products, and the power meter is such as the Bonard BND-10Y.
[0038] The power meter is used to observe the return light value in the laser and transmit the return light value to the control module; the drive current is used to drive the laser according to the drive current value.
[0039] The control module is used to: acquire the return light value of the initial spectrum under different laser drive currents; select the drive current corresponding to the return light value with difference among the return light values of different initial spectra as the set current value; change the initial spectrum and read the return light value under the current spectrum; the return light value under the current spectrum is obtained by loading the drive current to the set current value; select the spectrum with the return light value under the current spectrum that is lower than a first set threshold as the preliminary screening result; select the preliminary screening result corresponding to the highest drive current value in the self-pulse phenomenon as the optimal spectrum; the drive current value of the laser drive current increases from the set current value until the spectrum self-pulse phenomenon in the preliminary screening result appears.
[0040] In another exemplary embodiment, the power meter is connected to an optical fiber coupler in the laser.
[0041] In another exemplary embodiment, the power meter is connected to an isolator between the pre-amplification optical path and the main amplification optical path of the laser.
[0042] In practical applications, such as Figure 5 As shown, the return light can be detected not only from the fiber optic coupler, but also from the isolator between the pre-amplification optical path and the main amplification optical path. Figure 5 (ISO) output.
[0043] exist Figure 5In this laser system, the laser consists of two parts: a phase-modulated seed source and a master oscillator stage for amplification. After phase modulation and broadening, the broadened laser output enters the pre-amplification stage, with an output power of tens of W. The output light from the pre-amplification stage passes through an isolator (ISO), a mode field adapter (MFA), and a cladding optical filter (CPS) before entering the master amplification stage, thus amplifying the laser's power. A three-terminal isolator is connected between the pre-amplification and master amplification paths. The returned light is then fed into a spectrometer or converted into an electrical signal by a photodetector and fed into an oscilloscope. When the spectrometer (such as the Siyi Electronics 6362 series spectrometer) detects a pulse in the returned light spectrum, or when the oscilloscope measures a pulse in the electrical signal, it indicates that the spectral shape has reached the SBS threshold on the laser. Figure 5 and Figure 2 The main difference is that the fiber optic coupler has been eliminated.
[0044] In another exemplary embodiment, the automatic laser phase modulation spectrum screening device further includes: a spectrometer; the spectrometer is used to measure the return spectral shape of the laser.
[0045] In another exemplary embodiment, the control module is a computer.
[0046] This application achieves preliminary spectral shape screening by detecting returned light readings at relatively low laser output power. With fixed laser conditions and a constant driving current, an automatic spectral shape screening platform can be established to achieve automatic spectral shape screening.
[0047] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 7 As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores automatic laser phase modulation spectrum selection data. The I / O interfaces are used for information exchange between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements an automatic laser phase modulation spectrum selection method.
[0048] Those skilled in the art will understand that Figure 7 The structures shown are merely block diagrams of some structures related to the present application and do not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than shown in the figures, or combine certain components, or have different component arrangements. In an exemplary embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described method embodiments.
[0049] In one exemplary embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the above-described method embodiments.
[0050] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the above-described method embodiments.
[0051] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.
[0052] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).
[0053] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.
[0054] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0055] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. An automatic selection method for laser phase modulation spectrum, characterized in that, The automatic laser phase modulation spectrum screening method includes: Obtain the return light values of the initial spectrum under different laser drive currents; Select the driving current corresponding to the difference in the returned light value among the different initial spectrum shapes as the set current value; The initial spectrum shape is changed and the return light value under the current spectrum shape is read; the return light value under the current spectrum shape is obtained by applying the driving current to the set current value; Select the spectral patterns whose returned light values are lower than the first set threshold under the current spectral pattern as the preliminary screening results; The preliminary screening result corresponding to the highest driving current value in the self-pulse phenomenon is selected as the optimal spectrum; the driving current value of the laser driving current is increased from the set current value until the spectrum self-pulse phenomenon in the preliminary screening result appears.
2. The automatic laser phase modulation spectrum selection method according to claim 1, characterized in that, The returned light value that shows a difference is a returned light value that is less than a second set threshold.
3. An automatic laser phase modulation spectrum screening device, characterized in that, The automatic laser phase modulation spectrum screening device applies the automatic laser phase modulation spectrum screening method according to any one of claims 1-2, and the automatic laser phase modulation spectrum screening device includes: a control module, a driving power supply, a laser, and a power meter connected in sequence. The power meter is used to observe the return light value in the laser and transmit the return light value to the control module; the drive current is used to drive the laser according to the drive current value. The control module is used for: Obtain the return light values of the initial spectrum under different laser drive currents; Select the driving current corresponding to the difference in the returned light value among the different initial spectrum shapes as the set current value; The initial spectrum shape is changed and the return light value under the current spectrum shape is read; the return light value under the current spectrum shape is obtained by applying the driving current to the set current value; Select the spectral patterns whose returned light values are lower than the first set threshold under the current spectral pattern as the preliminary screening results; The preliminary screening result corresponding to the highest driving current value in the self-pulse phenomenon is selected as the optimal spectrum; the driving current value of the laser driving current is increased from the set current value until the spectrum self-pulse phenomenon in the preliminary screening result appears.
4. The automatic laser phase modulation spectrum screening device according to claim 3, characterized in that, The power meter is connected to the fiber optic coupler in the laser.
5. The automatic laser phase modulation spectrum screening device according to claim 3, characterized in that, The power meter is connected to the isolator between the pre-amplification optical path and the main amplification optical path of the laser.
6. The automatic laser phase modulation spectrum screening device according to claim 3, characterized in that, Also includes: Spectrometer; The spectrometer is used to measure the returned spectral shape of the laser.
7. The automatic laser phase modulation spectrum screening device according to claim 3, characterized in that, The control module is a computer.
8. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the automatic laser phase modulation spectrum screening method according to any one of claims 1-2.
9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the automatic laser phase modulation spectrum selection method according to any one of claims 1-2.
10. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the automatic laser phase modulation spectrum selection method according to any one of claims 1-2.