Spectrum matching method applied to fiber and solid hybrid master oscillator power amplifier

Abstract

The application discloses a spectrum matching system applied to a fiber and solid hybrid master oscillator power amplifier, and the system comprises a master oscillator, an optical circulator, a fiber Bragg grating, a fiber amplification unit, a passive optical fiber and a solid power amplification unit; the master oscillator, the fiber Bragg grating and the fiber power amplification unit are coupled with a first port, a second port and a third port of the optical circulator respectively; the fiber power amplification unit is connected with the passive optical fiber and the solid power amplification unit in sequence; the temperature of the fiber Bragg grating is changed through a temperature control device, so that the center wavelength of the master oscillator output is matched with the emission cross-section peak value of the solid power amplification unit; the light beam is pre-amplified through the fiber amplification unit, the spectrum is narrowed or widened based on the inverse four-wave mixing effect, and the spectrum of the fiber amplification unit output light is matched with the emission spectrum of the solid power amplification unit. The application realizes accurate control of spectrum matching, and thus improves the efficiency of laser amplification.

Description

Technical Field

[0001] This invention relates to the field of spectral matching technology, and specifically to a spectral matching method applied to a hybrid optical fiber and solid-state master oscillator power amplifier. Background Technology

[0002] Laser technology has a wide range of applications in many fields. However, with the increasing demands on the performance of laser technology, such as high power, high spectral quality, and high frequency stability, the design and optimization of lasers has become an important research direction. In particular, for hybrid pulsed fiber / solid-state lasers, the problem of spectral matching has always been one of the key factors affecting their performance.

[0003] The working principle of hybrid pulsed fiber lasers and solid-state lasers mainly utilizes the laser pulses generated by fiber seed lasers, which are then amplified by solid-state amplifiers. Due to the differences in materials and structures between fiber lasers and solid-state amplifiers, their emission cross-section peaks are usually inconsistent. This inconsistency leads to spectral mismatch, which further affects the amplification efficiency and output quality of the laser.

[0004] Furthermore, in a hybrid pulsed fiber-solid-state laser system, due to the nonlinear effects within the fiber laser, especially self-phase modulation (SPM) which is particularly pronounced under high power and long fiber length conditions and can broaden the spectrum, the emission spectral width of the fiber amplifier is usually greater than that of the solid-state amplifier. This necessitates considering and resolving the spectral width matching problem between each amplification stage during the design and optimization process to ensure that the signal light spectrum can be completely covered by the emission spectrum of the gain medium, thereby achieving efficient optical pulse amplification. This problem is usually solved by selecting and designing specific solid-state amplification media, adjusting the operating parameters of the solid-state amplifier to adapt to the spectral characteristics of the fiber laser, or using specific fiber design and adjusting the operating parameters of the fiber laser. However, these methods either lead to amplifier performance degradation, fail to achieve accurate spectral matching, or are complex to operate and difficult to implement.

[0005] Therefore, there is an urgent need to provide an easy-to-operate method to achieve spectral matching between optical fiber and solid-state amplification, and to improve the precision of control. Summary of the Invention

[0006] To overcome the defects and shortcomings of existing technologies, this invention provides a spectral matching method for a hybrid optical fiber and solid-state master oscillator power amplifier.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention provides a spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier, comprising: a master oscillator, an optical circulator, a fiber Bragg grating, an optical fiber amplification unit, a passive optical fiber, and a solid-state power amplification unit, wherein the optical circulator is provided with a first port, a second port, and a third port;

[0009] The output port of the main oscillator is coupled to the first port of the optical circulator, the fiber Bragg grating is coupled to the second port of the optical circulator, the input end of the fiber power amplifier unit is coupled to the third port of the optical circulator, the output end of the fiber power amplifier stage is connected to the input end of the passive fiber, and the output end of the passive fiber is connected to the solid-state power amplifier unit.

[0010] The main oscillator outputs an initial beam, and the fiber Bragg grating is placed in a temperature control device. By changing the temperature of the fiber Bragg grating through the temperature control device, the reflection peak wavelength of the fiber Bragg grating is adjusted, and the center output wavelength of the initial beam of the main oscillator is adjusted, so that the center wavelength of the initial beam output by the main oscillator matches the peak value of the emission cross section of the solid-state power amplifier unit.

[0011] After spectral matching, the initial beam is pre-amplified by the fiber optic amplifier unit. When the light output from the fiber optic amplifier unit passes through the passive fiber, the spectrum is narrowed or broadened based on the inverse four-wave mixing effect, so that the spectrum of the output light from the fiber optic amplifier unit matches the emission spectrum of the solid-state power amplifier unit.

[0012] As a preferred technical solution, the main oscillator adopts a random fiber laser and a semi-open cavity structure.

[0013] As a preferred technical solution, the fiber amplification unit includes multiple laser diodes, a beam combiner, and an active fiber. The multiple laser diodes are respectively connected to the beam combiner, and the laser diodes serve as pump sources. The beam combiner is connected to the active fiber, and the active fiber is connected to the passive fiber.

[0014] As a preferred technical solution, the active optical fiber is ytterbium-doped optical fiber.

[0015] As a preferred technical solution, the passive optical fiber is a large effective area dispersion-shifted single-mode optical fiber.

[0016] As a preferred technical solution, when narrowing the spectrum, the light is selected to propagate in the normal dispersion region of the passive optical fiber, which is the wavelength range >1000nm.

[0017] As a preferred technical solution, the solid-state power amplifier unit includes a yttrium aluminum garnet crystal and a pump source corresponding to its absorption wavelength.

[0018] This invention also provides a spectral matching method for a spectral matching system applied to a hybrid optical fiber and solid-state master oscillator power amplifier, comprising the following steps:

[0019] Set the initial center wavelength of the master oscillator beam to match the peak wavelength of the emission cross section of the solid-state power amplifier unit, and set the initial value of the reflection peak wavelength of the fiber Bragg grating;

[0020] The deviation of the center wavelength of the initial beam of the master oscillator is detected, and the temperature of the fiber Bragg grating is changed by a temperature control device to adjust the reflection peak wavelength of the fiber Bragg grating in order to maintain matching with the peak wavelength of the emission cross section of the solid-state power amplifier unit.

[0021] Adjust the center output wavelength of the initial beam of the master oscillator so that the center wavelength of the initial beam output by the master oscillator matches the peak value of the emission cross section of the solid-state power amplifier unit;

[0022] After spectral matching, the initial beam is pre-amplified by the fiber optic amplifier unit. When the light output from the fiber optic amplifier unit passes through the passive fiber, the spectrum is narrowed or broadened based on the inverse four-wave mixing effect, so that the spectrum of the output light from the fiber optic amplifier unit matches the emission spectrum of the solid-state power amplifier unit.

[0023] As a preferred technical solution, spectral narrowing or broadening based on the inverse four-wave mixing effect specifically includes:

[0024] The nonlinear length can be changed by adjusting the gain of the fiber amplifier unit, or the dispersion length can be changed by adjusting the length of the passive fiber.

[0025] Spectral broadening is achieved when the dispersion length at the fiber input is much greater than the nonlinear length.

[0026] When the dispersion length and nonlinear length are similar, spectral narrowing is achieved.

[0027] As a preferred technical solution, a second optical circulator and a second fiber Bragg grating are also provided;

[0028] The second optical circulator is provided with a first port, a second port and a third port;

[0029] The second fiber Bragg grating is placed in a temperature control device, and the temperature of the fiber Bragg grating is changed by the temperature control device to adjust the wavelength of the reflection peak of the fiber Bragg grating;

[0030] The output end of the passive optical fiber is coupled to the first port of the second optical circulator, the second fiber Bragg grating is coupled to the second port of the second optical circulator, and the solid-state power amplifier unit is coupled to the third port of the second optical circulator.

[0031] Frequency selection is performed based on the peak emission cross-section of the solid-state power amplifier unit, and light with a frequency matching the peak emission cross-section is selected to pass through, thus achieving spectral matching.

[0032] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0033] (1) Compared to existing systems that directly use spectral filters, which introduce additional losses due to spectral filters, this invention uses nonlinear effects to compress light, thereby achieving higher spectral brightness.

[0034] (2) Existing methods for achieving spectral narrowing using nonlinear effects first broaden the initial beam to negative chirp, and then use the self-phase modulation effect of nonlinear optical fiber to narrow the spectrum to achieve spectral matching. However, this invention uses the nonlinear optical phenomenon of inverse four-wave mixing to narrow the optical spectrum. Compared with existing methods, it does not require the introduction of a broadener. By increasing or decreasing the pump power and fiber length, the spectral width of the laser can be finely controlled to adapt to various application scenarios.

[0035] (3) The present invention controls the center output wavelength of the laser by changing the fiber Bragg grating. This method is more gentle and controllable than directly changing the working conditions of the laser, and will not have a negative impact on the stability and lifespan of the laser. At the same time, since the temperature control precision of the fiber Bragg grating is high, the precise wavelength control of the fiber seed laser can be achieved, ensuring the accuracy of spectral matching. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the spectral matching system applied to the hybrid optical fiber and solid-state master oscillator power amplifier of Embodiment 1.

[0037] Figure 2 This is a schematic diagram comparing the spectrum after spectral matching with the initial beam spectrum in Example 1.

[0038] Figure 3 This is a schematic diagram of the spectral matching system applied to the hybrid master oscillator power amplifier of optical fiber and solid-state in this embodiment 2.

[0039] Among them, 1-master oscillator, 2-optical circulator, 3-fiber Bragg grating, 4-fiber amplification unit, 5-large effective area fiber, 6-solid-state power amplification unit, 7-second optical circulator, 8-second fiber Bragg grating. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] Example 1

[0042] like Figure 1 As shown, a spectral matching system for a hybrid fiber and solid-state master oscillator power amplifier includes: a master oscillator 1, an optical circulator 2, a fiber Bragg grating 3 (FBG), a fiber amplification unit 4, a large effective area fiber 5 (LEAF), and a solid-state power amplification unit 6.

[0043] Among them, the fiber Bragg grating 3 is placed after the output port of the main oscillator 1. The main oscillator is equipped with a fiber seed laser. The output port of the main oscillator 1 is coupled to the first port of the optical circulator 2. The fiber Bragg grating 3 is coupled to the second port of the optical circulator 2. The input end of the fiber power amplifier stage 4 is coupled to the third port of the optical circulator 2. The output end of the fiber power amplifier stage 4 is connected to the input end of the large effective area fiber 5. The output end of the large effective area fiber 5 is connected to the solid-state power amplifier unit 6.

[0044] In this embodiment, the fiber Bragg grating is placed in a temperature control device. The temperature control device is used to change the temperature of the fiber Bragg grating to fine-tune its reflection peak wavelength, thereby adjusting the center output wavelength of the master oscillator. Based on the characteristic that the reflection peak wavelength of the fiber Bragg grating changes with temperature, the center output wavelength of the fiber seed laser in the master oscillator is precisely adjusted by precisely controlling the temperature of the fiber Bragg grating. This allows the center wavelength of the initial beam output by the master oscillator to match the peak emission cross-section of the solid-state power amplifier unit, achieving preliminary spectral matching.

[0045] In this embodiment, it is assumed that the peak wavelength of the emission cross-section of the solid-state power amplifier unit is 1060nm, and the fiber Bragg grating (FBG) is a common Type I FBG with a temperature response coefficient of 10pm / ℃.

[0046] The following spectral matching scheme can be formulated:

[0047] 1. First, it is necessary to set the center wavelength of the output beam of the master oscillator to match the peak wavelength of the emission cross section of the solid-state power amplifier unit, which is set to 1060nm;

[0048] 2. In the initial state of the system, the reflection peak wavelength of the fiber Bragg grating is set to 1060nm. At this time, assume the temperature of the FBG is 25℃.

[0049] 3. During system operation, if the center wavelength of the output beam of the main oscillator deviates from 1060nm, for example, if the measured wavelength is 1061nm, then the reflection peak wavelength of the fiber Bragg grating (FBG) needs to be adjusted to reduce it by 1nm in order to maintain the match with the peak wavelength of the emission cross section of the solid-state power amplifier unit.

[0050] 4. According to the temperature response coefficient of FBG, for every 1°C change in the temperature of FBG, the wavelength of the reflection peak will change by 10 pm, or 0.01 nm. Therefore, in order to reduce the wavelength of the reflection peak by 1 nm, the temperature of FBG needs to be reduced by 100°C.

[0051] 5. Using a temperature control device, the temperature of the FBG is reduced from 25℃ to -75℃. This reduces the reflection peak wavelength of the FBG from 1060nm to 1059nm, thereby adjusting the center wavelength of the output beam of the main oscillator to 1059nm, matching the peak wavelength of the emission cross-section of the solid-state power amplifier unit.

[0052] The above steps can be implemented through an automated control system that monitors the center wavelength of the output beam of the master oscillator in real time. If a deviation is detected, it will be corrected by adjusting the temperature of the FBG.

[0053] In this embodiment, the seed light output from the master oscillator is pre-amplified by an optical fiber amplification unit. A passive optical fiber is integrated after the optical fiber amplification unit so that when the light passes through this passive optical fiber, the inverse four-wave mixing effect (IFWM) of the nonlinear optical fiber is used to narrow or broaden the output spectrum, so that the spectrum of the output light of the optical fiber amplification unit matches the emission spectrum of the subsequent solid-state power amplification unit. The passive optical fiber integrated after the optical fiber amplification unit is a large effective area optical fiber 5 (LEAF). When the spectrum is narrowed by the inverse four-wave mixing effect, the light propagates in the normal dispersion region of the large effective area optical fiber.

[0054] In this embodiment, in order to achieve the effect of spectral narrowing, it is necessary to select the normal dispersion region of light in a large effective area fiber. This embodiment uses a large effective area dispersion shifted single-mode fiber LEAF, whose zero dispersion point is at 1000nm, and whose normal dispersion region is the wavelength range >1000nm.

[0055] In this embodiment, the master oscillator is a random fiber laser (RFL) with a semi-open cavity design, and its positive feedback comes from weak Rayleigh scattering in the passive fiber.

[0056] The basic principle of inverse four-wave mixing is as follows: when a high-power field containing many longitudinal modes propagates in a normally dispersive fiber, its input field can self-act by redistributing energy from the surrounding wavelengths (i.e., "pump") to the central region (i.e., "signal"). This process can be regarded as a "self-pumping" mechanism, which consumes energy at the energy-reduced spectral tail and increases power in the central frequency region. Experimental and numerical simulation results show that after propagation through a normally dispersive fiber of appropriate length, the spectral width of the signal generated by the random fiber laser (RFL) narrows, producing a state characterized by a narrow spectrum and random time field distribution, exhibiting significant stability. Specifically, by introducing a section of normally dispersive fiber with a large effective area into the fiber amplification unit, and by increasing or decreasing the gain of the fiber amplification unit or changing the length of the large effective area fiber, the intensity of this nonlinear effect can be controlled, thereby achieving fine spectral tuning and narrowing, and ultimately achieving spectral matching between the fiber and the solid-state amplification.

[0057] In this embodiment, when the dispersion length (Ld) at the fiber input end is much greater than the nonlinear length (LNL), spectral broadening occurs. On the other hand, when the dispersion length and nonlinear length are similar, nonlinear spectral narrowing is observed. Therefore, by adjusting the gain of the fiber amplification unit and the length of the large effective area fiber, the ratio of the dispersion length to the nonlinear length (Ld / LNL) at the fiber input end can be controlled. Specifically:

[0058] 1. By adjusting the power of the pump light, the gain of the fiber optic amplifier unit is changed, thereby changing the power of the amplified light. This will change the nonlinear length (LNL), as it is inversely proportional to the power of the light.

[0059] 2. By changing the length of a large effective area optical fiber, the distance that light travels in the optical fiber can be changed, thereby changing the dispersion length (Ld).

[0060] The two methods described above can be used to control the ratio of dispersion length to nonlinear length (Ld / LNL) at the fiber input end, thereby achieving spectral modulation and narrowing. In order to achieve spectral matching between the fiber and the solid-state amplifier, it is necessary to determine the optimal gain and fiber length through experiments or simulations.

[0061] Combination Figure 1 As shown, the fiber amplification unit uses a laser diode (LD) as the pump source and injects it into the active fiber through a combiner. Figure 1 The optical fiber within the dashed box (where the active optical fiber is ytterbium-doped fiber);

[0062] In this embodiment, the laser crystal used in the solid-state power amplifier unit includes a yttrium aluminum garnet crystal and a pump source corresponding to its absorption wavelength.

[0063] In this embodiment, the implementation process is as follows: the initial beam output by the main oscillator is first wavelength-selected by a fiber Bragg grating (FBG). The fiber Bragg grating is placed in a temperature control device. By finely adjusting the temperature, the center wavelength of the initial beam can be matched with the peak emission cross-section of the subsequent optical fiber and solid-state power amplifier unit.

[0064] After initial spectral matching, the beam is coupled into an optical fiber power amplifier unit for power amplification. Then, before the amplified beam is coupled into a solid-state power amplifier unit, it is passed through a nonlinear passive optical fiber. By controlling the gain of the optical fiber power amplifier stage or changing the length of the passive optical fiber, the intensity of the IFWM effect generated by the beam propagating within it is increased or decreased, thereby achieving fine control of the spectral width. This allows for precise spectral matching with the subsequent solid-state power amplifier unit. This embodiment achieves precise control of spectral matching, thereby improving the efficiency of laser amplification and maintaining excellent output pulse and beam quality.

[0065] Specifically, the random fiber laser used in this embodiment operates in continuous wave (cw) mode at a wavelength of 1070 nm. Its initial output beam is first wavelength-selected by a fiber Bragg grating. This is achieved by placing the fiber Bragg grating in an environment with precise temperature control of ±0.1°C, thereby making its reflection peak wavelength tunable. The fiber Bragg grating used has a center wavelength of 1070 nm, a reflectivity of 0.99, and a bandwidth of 0.3 nm. After adjustment, as shown... Figure 2 As shown, the center wavelength of the initial beam can be precisely matched with the peak emission cross-section of the subsequent fiber and solid-state power amplifier unit. Subsequently, the wavelength-selected beam is coupled into the fiber power amplifier stage, which consists of four LDs pumped by a (6+1)×1 combiner using 3m LMA-YDF 25 / 250 gain fiber. After the power amplifier stage, a 100km long large effective area fiber with a zero-dispersion wavelength of approximately 1135nm is placed, allowing the light to propagate in its normal dispersion region. During this process, when the pump power is 0.7W, the spectral width is compressed from the initial 2.9nm to 2.4nm by the inverse four-wave mixing effect. This spectral width is slightly narrower than the emission spectral width of the Yb:YAG laser crystal and falls within the gain bandwidth coverage of the crystal. Therefore, all spectral components can be amplified by the solid-state power amplifier unit, demonstrating that this method successfully achieves good spectral matching between the fiber and the solid-state power amplifier unit.

[0066] Example 2

[0067] like Figure 3As shown, this embodiment provides another spectral matching system for a hybrid fiber and solid-state master oscillator power amplifier, which is a further improvement on embodiment 1. The difference between embodiment 1 and embodiment 1 is that a second fiber Bragg grating 8 with a temperature control device is inserted before the solid-state power amplification unit. Specifically, it is configured as follows:

[0068] Among them, fiber Bragg grating 3 serves as the first fiber Bragg grating, and optical circulator 2 serves as the first optical circulator;

[0069] The first fiber Bragg grating is placed after the output port of the main oscillator 1. The main oscillator contains a fiber seed laser. The output port of the main oscillator 1 is coupled to the first port of the first optical circulator. The first fiber Bragg grating 3 is coupled to the second port of the first optical circulator. The input end of the fiber power amplifier stage 4 is coupled to the third port of the first optical circulator. The output end of the fiber power amplifier stage 4 is connected to the input end of the large effective area fiber 5. The output end of the large effective area fiber 5 is coupled to the first port of the second optical circulator 7. The second fiber Bragg grating 8 is coupled to the second port of the second optical circulator 7. The solid-state power amplifier unit 6 is coupled to the third port of the second optical circulator 7.

[0070] The spectral matching system in this embodiment can select frequencies based on the peak emission cross-section of the laser crystal in the solid-state power amplifier unit, allowing only light with frequencies matching the peak emission cross-section of the laser crystal to pass through, thereby further modulating the spectrum and achieving a more refined spectral matching effect when needed.

[0071] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A spectral matching system for a hybrid fiber-to-solid-state master oscillator power amplifier, characterized in that, include: The system includes a master oscillator, an optical circulator, a fiber Bragg grating, an optical fiber amplification unit, a passive optical fiber, and a solid-state power amplification unit. The optical circulator is provided with a first port, a second port, and a third port. The output port of the main oscillator is coupled to the first port of the optical circulator, the fiber Bragg grating is coupled to the second port of the optical circulator, the input end of the fiber power amplifier unit is coupled to the third port of the optical circulator, the output end of the fiber power amplifier stage is connected to the input end of the passive fiber, and the output end of the passive fiber is connected to the solid-state power amplifier unit. The main oscillator outputs an initial beam, and the fiber Bragg grating is placed in a temperature control device. By changing the temperature of the fiber Bragg grating through the temperature control device, the reflection peak wavelength of the fiber Bragg grating is adjusted, and the center output wavelength of the initial beam of the main oscillator is adjusted, so that the center wavelength of the initial beam output by the main oscillator matches the peak value of the emission cross section of the solid-state power amplifier unit. After spectral matching, the initial beam is pre-amplified by the fiber optic amplifier unit. When the light output from the fiber optic amplifier unit passes through the passive fiber, the spectrum is narrowed or broadened based on the inverse four-wave mixing effect, so that the spectrum of the output light from the fiber optic amplifier unit matches the emission spectrum of the solid-state power amplifier unit.

2. The spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 1, characterized in that, The main oscillator is a random fiber laser with a semi-open cavity structure.

3. The spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 1, characterized in that, The fiber amplification unit includes multiple laser diodes, a beam combiner, and an active fiber. The multiple laser diodes are respectively connected to the beam combiner, and the laser diodes serve as pump sources. The beam combiner is connected to the active fiber, and the active fiber is connected to the passive fiber.

4. The spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 3, characterized in that, The active optical fiber is ytterbium-doped fiber.

5. The spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 1, characterized in that, The passive optical fiber is a large effective area dispersion-shifted single-mode fiber.

6. The spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 1, characterized in that, When performing spectral narrowing, light is selected to propagate in the normal dispersion region of the passive optical fiber, which is the wavelength range >1000nm.

7. The spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 1, characterized in that, The solid-state power amplifier unit includes a ytterbium-doped yttrium aluminum garnet crystal and a pump source corresponding to its absorption wavelength.

8. The spectral matching method for a spectral matching system applied to a hybrid optical fiber and solid-state master oscillator power amplifier according to any one of claims 1-7, characterized in that, Includes the following steps: Set the initial center wavelength of the master oscillator beam to match the peak wavelength of the emission cross section of the solid-state power amplifier unit, and set the initial value of the reflection peak wavelength of the fiber Bragg grating; The deviation of the center wavelength of the initial beam of the master oscillator is detected, and the temperature of the fiber Bragg grating is changed by a temperature control device to adjust the reflection peak wavelength of the fiber Bragg grating in order to maintain matching with the peak wavelength of the emission cross section of the solid-state power amplifier unit. Adjust the center output wavelength of the initial beam of the master oscillator so that the center wavelength of the initial beam output by the master oscillator matches the peak value of the emission cross section of the solid-state power amplifier unit; After spectral matching, the initial beam is pre-amplified by the fiber optic amplifier unit. When the light output from the fiber optic amplifier unit passes through the passive fiber, the spectrum is narrowed or broadened based on the inverse four-wave mixing effect, so that the spectrum of the output light from the fiber optic amplifier unit matches the emission spectrum of the solid-state power amplifier unit.

9. The spectral matching method for a spectral matching system applied to a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 8, characterized in that, Spectral narrowing or broadening based on inverse four-wave mixing effects specifically includes: The nonlinear length can be changed by adjusting the gain of the fiber amplifier unit, or the dispersion length can be changed by adjusting the length of the passive fiber. Spectral broadening is achieved when the dispersion length at the fiber input is much greater than the nonlinear length. When the dispersion length and nonlinear length are similar, spectral narrowing is achieved.

10. The spectral matching system for a hybrid optical fiber and solid-state master oscillator power amplifier according to claim 1, characterized in that, It also features a second optical circulator and a second fiber Bragg grating; The second optical circulator is provided with a first port, a second port and a third port; The second fiber Bragg grating is placed in a temperature control device, and the temperature of the fiber Bragg grating is changed by the temperature control device to adjust the wavelength of the reflection peak of the fiber Bragg grating; The output end of the passive optical fiber is coupled to the first port of the second optical circulator, the second fiber Bragg grating is coupled to the second port of the second optical circulator, and the solid-state power amplifier unit is coupled to the third port of the second optical circulator. Frequency selection is performed based on the peak emission cross-section of the solid-state power amplifier unit, and light with a frequency matching the peak emission cross-section is selected to pass through, thus achieving spectral matching.

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