All-solid-state pulse laser based on semiconductor amplifier

Abstract

The invention discloses an all-solid-state pulse laser based on a semiconductor amplifier, and relates to the technical field of wind finding radars, and the laser comprises a laser seed source, an isolator, a semiconductor amplifier, a pulse driving power supply, a balance detector, a frequency shifter, and a circulator. The laser seed source emits a stable narrow-linewidth laser signal to the isolator, the isolator emits laser, the laser is processed by the semiconductor amplifier and the frequency shifter, the processed laser is finally output to the subsequent light receiving and transmitting system through the circulator and finally emitted to the atmosphere, and the light receiving and transmitting system outputs a returned echo signal to the circulator. The circulator outputs an echo signal to the balance detector, the balance detector performs differential detection on the reference light and the echo signal, finally converts a light signal into an electric signal, and transmits the electric signal to the data processing unit for analysis and wind speed measurement; the pulse driving power supply drives the semiconductor amplifier in a short-time overload mode to form high-energy optical pulses, and meanwhile the chopping function is achieved to replace an AOM.

Description

Technical Field

[0001] The invention relates to the technical field of wind measurement radar, and in particular to an all-solid-state pulse laser based on a semiconductor amplifier. Background Art

[0002] Wind radar is a laser radar that measures wind speed based on the principle of coherent Doppler frequency shift velocity measurement. It emits a pulse laser with a certain frequency shift, detects the frequency of echo signals with different time delays, and determines the wind speed at different distances from the wind measurement surface. Its system usually consists of a narrow linewidth pulse laser, an optical transceiver, a balanced detector, and a data processing system. For its laser system, due to the low atmospheric background scattering rate, the output laser usually requires high power. At the same time, coherent Doppler frequency shift velocity measurement requires the coherence length of the laser to be more than twice the detection distance, which requires the laser of the wind radar to have a narrow linewidth. Such a laser system usually consists of four parts: a narrow linewidth seed light source, a laser amplifier, a frequency shift and chopping device, and a feedback control module. Among them, the narrow linewidth seed light source usually uses a DFB or FP semiconductor laser chip, the optical amplifier usually uses an erbium-doped fiber amplifier (EDFA), and the frequency shift and chopping use an acousto-optic modulator (AOM).

[0003] Most current wind radar products use EDFA for optical amplification and connect AOM in series for frequency shifting and chopping. Due to the large size, high power consumption and high batch production cost of EDFA and AOM, the entire wind radar system is large in size and high in energy consumption, which limits the application scope of wind radar. Summary of the invention

[0004] The purpose of the present invention is to provide a full solid-state pulse laser based on a semiconductor amplifier, which can replace the EDFA and AOM in the traditional wind radar laser through miniaturization, low power consumption and low cost design, so as to improve the performance and reliability of the system.

[0005] The technical solution of the present invention is: providing an all-solid-state pulse laser based on a semiconductor amplifier, the laser comprising: a laser seed source, an isolator, a semiconductor amplifier, a pulse drive power supply, a balanced detector, a frequency shifter, and a circulator;

[0006] The laser seed source emits a stable narrow-linewidth laser signal to the isolator. The isolator emits the laser, which is amplified by a semiconductor amplifier, processed by chopping, and modulated by a frequency shifter. It is finally output to the subsequent optical transceiver system through a circulator, and finally transmits and receives an echo signal to the atmosphere. The optical transceiver system outputs the returned echo signal to the circulator. The circulator outputs the echo signal to a balanced detector. The balanced detector performs differential detection on the reference light and the echo signal, and finally converts the optical signal into an electrical signal, which is transmitted to the data processing unit for analysis and wind speed measurement.

[0007] Among them, the semiconductor amplifier is driven by a pulse driving power supply. The pulse driving power supply uses extremely short pulse driving to overload the semiconductor amplifier for a short time and output high-energy pulse laser. The semiconductor amplifier and pulse driving power supply are completely shut down during non-working hours to reduce energy consumption and heat dissipation requirements, acting as an optical switch to chop the laser to form an optical pulse that meets the requirements, replacing the chopping function of the AOM in the current wind measurement radar laser.

[0008] In any of the above technical solutions, further, the laser also includes: a beam splitter;

[0009] The beam splitter is arranged between the isolator and the semiconductor amplifier, and the semiconductor amplifier is followed by a frequency shifter; the isolator emits laser light to the beam splitter, and the beam splitter divides the laser light into two paths, one of which is input into a balanced detector as a reference light, and the other enters the semiconductor amplifier for amplification and chopping processing.

[0010] In any of the above technical solutions, further, the laser seed source is a DBR semiconductor laser chip, and the residual light output by the rear end reflector of the laser seed source is output to a balanced detector as a reference light.

[0011] In any of the above technical solutions, further, a frequency shifter is arranged between the isolator and the semiconductor amplifier, the isolator emits laser to the frequency shifter, the frequency shifter processes the laser input to the frequency shifter, and finally generates frequency shifter output light and frequency shifter residual light, the frequency shifter output light is 1st order or -1st order diffraction light, the frequency shifter residual light is residual laser of 0th order diffraction, and the frequency shifter residual light is input into the balanced detector as reference light.

[0012] The beneficial effects of the present invention are:

[0013] The technical solution of the present invention adopts a semiconductor optical amplifier (SOA) to replace the traditional optical fiber amplifier (EDFA), which significantly reduces the overall size of the laser and facilitates integration and miniaturization applications.

[0014] In view of the characteristic of insufficient peak power of semiconductor amplifier (SOA), the present invention utilizes the characteristic that the pulse laser for wind measurement radar only needs a very short opening time, and through the extremely short pulse driving mode, the semiconductor amplifier is overloaded for a short time, exceeding its maximum power output, and then the driving current is turned off during the pulse interval to dissipate heat, so that the SOA can work beyond the rated power for a short time, thereby realizing high-energy pulse laser output. At the same time, the pulse driving with high power and low dark spot flow is used, which not only increases the peak power of the pulse, but also plays the role of an optical switch, chops the laser, and thus forms an optical pulse that meets the demand, replacing the chopping function of the AOM in the current wind measurement radar laser. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The advantages of the above and additional aspects of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0016] Figure 1 is a schematic diagram of Example 1 of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention;

[0017] Figure 2 is a schematic diagram of Example 2 of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention;

[0018] Figure 3 is a schematic diagram of Example 3 of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention;

[0019] Figure 4 1 is a vertical cross-sectional schematic diagram of a semiconductor amplifier of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention and several possible waveguide patterns of SOA;

[0020] Figure 5 1 is a schematic diagram for verifying output characteristics of Example 4 of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention;

[0021] Figure 6 is a schematic diagram of Example 5 of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention;

[0022] Figure 7 is a schematic diagram of Example 6 of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention;

[0023] Figure 8 Schematic diagram of Example 7 of an all-solid-state pulsed laser based on a semiconductor amplifier according to an embodiment of the present invention.

[0024] Among them, 1-laser seed source, 2-beam splitter, 3-isolator, 4-semiconductor amplifier, 5-pulse driving power supply, 6-balanced detector, 7-frequency shifter, 8-circulator, 40-multiple quantum well, 41-top heterostructure confinement layer, 42-bottom heterostructure confinement layer, 43-oxide insulating layer, 44-InP substrate, 71-frequency shifter incident light, 72-frequency shifter output light, 73-frequency shifter residual light. DETAILED DESCRIPTION

[0025] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0027] like Figure 1-3 As shown, this embodiment provides an all-solid-state pulse laser based on a semiconductor amplifier, which includes: a laser seed source 1, a beam splitter 2, an isolator 3, a semiconductor amplifier 4, a pulse drive power supply 5, a balanced detector 6, a frequency shifter 7, and a circulator 8.

[0028] The laser seed source 1 uses a DFB (distributed feedback) or FP (Fabry-Perot) semiconductor laser chip to provide a stable narrow-linewidth laser signal; the beam splitter 2 divides the laser emitted by the laser seed source 1 into two paths; the isolator 3 is used to prevent the reflected light in the optical path from flowing back to the laser seed light source to protect its stability and avoid damage; the semiconductor amplifier 4 (SOA) is used to amplify the input optical signal and realize the chopping of the optical signal by pulse driving. The SOA chip has a compact structure and does not require an additional pump light source, so it can be integrated into a smaller module; the pulse The driving power supply 5 provides a high-power pulse current to the semiconductor amplifier 4 to achieve short-term high-power amplification, while ensuring that it is completely powered off in the non-working state to reduce energy consumption and heat accumulation; the balanced detector 6 receives the signal returned from the circulator 8, performs differential detection with the reference optical signal, and finally converts the optical signal into an electrical signal, which is transmitted to the data processing unit for analysis; the frequency shifter 7 is used to adjust the frequency of the optical signal, and an acousto-optic modulator (AOM) or an electro-optic modulator can be selected; the circulator 8 controls the unidirectional propagation of light, can emit laser into the atmosphere, and receive the returned echo signal.

[0029] In view of the fact that the peak power of the semiconductor amplifier 4 (SOA) is insufficient, the present invention utilizes the fact that the pulse laser used in the wind measurement radar only needs an extremely short opening time. The pulse driving power supply 5 uses an extremely short pulse driving method to overload the semiconductor amplifier 4 for a short time, exceeding its maximum power output, and then turns off the driving current during the pulse interval to dissipate heat, allowing the semiconductor amplifier 4 to work beyond the rated power for a short time, thereby achieving high-energy pulse laser output.

[0030] The current intensity of the short-duration pulses of the pulse driving power supply 5 to the semiconductor amplifier 4 exceeds the upper limit of the recommended usage intensity of the semiconductor amplifier 4 .

[0031] The semiconductor amplifier 4 and the pulse drive power supply 5 are completely turned off during non-working hours to reduce energy consumption and heat dissipation requirements. They also act as optical switches to chop the laser to form optical pulses that meet the requirements, replacing the chopping function of the AOM in the current wind radar laser.

[0032] The semiconductor amplifier 4 includes a semiconductor gain chip, which is manufactured by first growing an active layer and a cover layer on a IIIV compound substrate, then forming a waveguide structure by means of photolithography and plasma etching, and finally forming electrodes by metallization.

[0033] like Figure 4 a is a vertical cross section of a semiconductor amplifier 4. In the first step, InP is grown on an InP substrate 44 by MBE or MOCVD. x Ga 1-x As y P 1-y The first step is to form a heterostructure confinement layer 42 at the bottom of the multi-quantum well 40 and a heterostructure confinement layer 41 at the top; the second step is to form a waveguide pattern on the photoresist by coating, exposing and developing, and then transfer the upper waveguide pattern to the heterostructure confinement layer 42 at the top by plasma etching to form a ridge waveguide; the third step is to form an oxide insulating layer 43 on the surface of the ridge waveguide by chemical vapor deposition (CVD) or physical sputtering to isolate the electrode and prevent short circuit; the fourth step is to form an upper electrode pattern on the waveguide at the current input part above the ridge waveguide by photolithography steps of coating, exposing and developing, and to carve the part where the electrode needs to contact by plasma etching; the fifth step is to evaporate the upper electrode by sputtering or evaporation; the sixth step is to coat the anti-reflection film on the end face of the waveguide by evaporation or sputtering after the chip is cut and the end face is polished to complete the chip manufacturing.

[0034] like Figure 4 b, 4c and 4d, the present invention lists several possible waveguide patterns of SOA, Figure 4 The width of the waveguides b and 4c remains unchanged along the propagation direction of the light wave, but Figure 4 The waveguide in c has a non-90° angle between the port and the waveguide direction, which can reduce the reflection of light waves at the end face; Figure 4 d shows a special SOA called TPA (Tapered Amplifier), which is characterized in that the waveguide is tapered and continuously widened along the propagation direction of the light wave, so that a wider waveguide mode is emitted, so that under the same power density, the light power that can be carried is higher, which makes the light wave power amplified by TPA larger, so that the present invention can be applied to long-distance wind measurement radar.

[0035] Embodiment 1:

[0036] like Figure 1 As shown, in the first embodiment of the present invention, the laser seed source 1 emits narrow linewidth laser to the isolator 3, the isolator 3 ensures the unidirectional propagation of the laser, the isolator 3 emits the laser to the beam splitter 2, the beam splitter 2 divides the laser into two paths, one path is input to the balanced detector 6 as a reference light, and the other path enters the semiconductor amplifier 4 for amplification and chopping processing.

[0037] The semiconductor amplifier 4 is driven by a pulse driving power supply 5. The pulse driving power supply 5 uses extremely short pulse driving to overload the semiconductor amplifier 4 for a short time and output high-energy pulse laser. The semiconductor amplifier 4 and the pulse driving power supply 5 are completely turned off during non-working hours to reduce energy consumption and heat dissipation requirements, and act as optical switches to chop the laser to form an optical pulse that meets the requirements, replacing the chopping function of the AOM in the current wind measurement radar laser.

[0038] The output end of the semiconductor amplifier 4 is connected to the frequency shifter 7, which processes the laser to ensure that its frequency change meets the Doppler frequency shift requirements of the wind measuring radar, and outputs the laser to the circulator 8, which outputs the laser to the subsequent optical transceiver system and finally emits it into the atmosphere.

[0039] The optical transceiver system outputs the returned echo signal to the circulator 8 , and the circulator 8 outputs the echo signal to the balanced detector 6 .

[0040] The balanced detector 6 performs differential detection on the reference light and the echo signal, and finally converts the optical signal into an electrical signal, which is transmitted to the data processing unit for analysis and wind speed measurement.

[0041] Embodiment 2:

[0042] like Figure 2 As shown, in the second embodiment of the present invention, the laser seed source 1 emits narrow linewidth laser to the isolator 3, the laser seed source 1 is a DBR semiconductor laser chip, the residual light output by the rear end reflector of the laser seed source 1 is output to the balanced detector 6 as reference light, the isolator 3 ensures the unidirectional propagation of the laser, the isolator 3 emits laser to the semiconductor amplifier 4, and the semiconductor amplifier 4 performs amplification and chopping processing.

[0043] The semiconductor amplifier 4 is driven by a pulse driving power supply 5. The pulse driving power supply 5 uses extremely short pulse driving to overload the semiconductor amplifier 4 for a short time and output high-energy pulse laser. The semiconductor amplifier 4 and the pulse driving power supply 5 are completely turned off during non-working hours to reduce energy consumption and heat dissipation requirements, and act as optical switches to chop the laser to form an optical pulse that meets the requirements, replacing the chopping function of the AOM in the current wind measurement radar laser.

[0044] The output end of the semiconductor amplifier 4 is connected to the frequency shifter 7, which processes the laser to ensure that its frequency change meets the Doppler frequency shift requirements of the wind measuring radar, and outputs the laser to the circulator 8, which outputs the laser to the subsequent optical transceiver system and finally emits it into the atmosphere.

[0045] The optical transceiver system outputs the returned echo signal to the circulator 8 , and the circulator 8 outputs the echo signal to the balanced detector 6 .

[0046] The balanced detector 6 performs differential detection on the reference light and the echo signal, and finally converts the optical signal into an electrical signal, which is transmitted to the data processing unit for analysis and wind speed measurement.

[0047] Embodiment 3:

[0048] like Figure 3 As shown, in the third embodiment of the present invention, the laser seed source 1 emits a narrow linewidth laser to the isolator 3, the isolator 3 ensures the unidirectional propagation of the laser, the isolator 3 emits the laser to the frequency shifter 7, the frequency shifter 7 processes the frequency shifter incident light 71 input to the frequency shifter 7 (i.e., the laser emitted by the isolator 3 to the frequency shifter 7) to ensure that its frequency change meets the requirements of the wind measurement radar for the Doppler frequency shift, and finally generates the frequency shifter output light 72 and the frequency shifter residual light 73, the frequency shifter output light 72 is the 1st or -1st order diffraction light, the frequency shifter residual light 73 is the residual laser of the 0th order diffraction, and since the frequency of the 0th order diffraction light has not changed, the frequency shifter residual light 73 is input as the reference light to the balanced detector 6.

[0049] The frequency shifter output light 72 enters the semiconductor amplifier 4, which performs amplification and chopping. The semiconductor amplifier 4 is driven by a pulse drive power supply 5, which drives the semiconductor amplifier 4 to be overloaded for a short time through extremely short pulse driving, thereby outputting high-energy pulse laser. The semiconductor amplifier 4 and the pulse drive power supply 5 are completely shut down during non-working hours to reduce energy consumption and heat dissipation requirements, thereby playing the role of an optical switch, chopping the laser, and thus forming an optical pulse that meets the requirements, thereby replacing the chopping function of the AOM in the current wind measurement radar laser.

[0050] The semiconductor amplifier 4 outputs the laser to the circulator 8, and the circulator 8 outputs the laser to the subsequent optical transceiver system and finally emits it into the atmosphere.

[0051] The optical transceiver system outputs the returned echo signal to the circulator 8 , and the circulator 8 outputs the echo signal to the balanced detector 6 .

[0052] The balanced detector 6 performs differential detection on the reference light and the echo signal, and finally converts the optical signal into an electrical signal, which is transmitted to the data processing unit for analysis and wind speed measurement.

[0053] Embodiment 4:

[0054] In order to verify the feasibility of this solution, the present invention verifies the amplifier output characteristics under overload pulse driving in an independently packaged device system through optical fiber connection.

[0055] like Figure 5 As shown, the technical solution of the present invention is verified on a commonly used 1550nm SOA. When the peak current of the external drive reaches 6 times the maximum continuous drive current, a pulse output with a peak power of more than 4 times is achieved. In order to verify the reliability of this technical solution, the SOA is also tested for life. The test results show that under this operation method, the time it takes for the power to be reduced to 1 / e is close to 51 years. Its 5 years of continuous operation can still guarantee an output power of more than 90% of the maximum peak power.

[0056] Embodiment 5:

[0057] Several implementations including technical details of laser delivery are proposed, the first of which utilizes fiber optic packaging, such as Figure 6 As shown, according to the connection method of Example 3, the laser input / output interfaces of each component are connected by optical fiber.

[0058] Embodiment 6:

[0059] The second solution is based on the implementation of system micro-assembly, such as Figure 7 As shown, discrete chips such as laser seed source 1, isolator 3, beam splitter 2, semiconductor amplifier 4, and frequency shifter 7 are fixed on a heat sink after being packaged by COC. The light emitted by the laser seed source 1 through the isolator 3 is shaped by a microlens or a microlens group, so that its spot matches the spot mode of the SOA waveguide incident end and is coupled to the incident end of the semiconductor amplifier 4. The light beam emitted by the semiconductor amplifier 4 through the isolator 3 is then shaped by a microlens or a microlens group, collimated into a Gaussian beam in free space, and coupled to the acousto-optic crystal used for the next level of frequency shift. The light beam passes through the acousto-optic crystal to emit a deflection of the acoustic wave to achieve frequency shift. In this implementation method, the entire system before the circulator forms a high-power pulse laser module.

[0060] Embodiment 7:

[0061] The third solution is based on heterogeneous chip on-chip integration, such as Figure 8As shown, the laser seed source 1, beam splitter 2, semiconductor amplifier 4 and frequency shifter 7 are integrated on the same silicon chip by heterogeneous bonding. The laser propagates in the heterogeneous chip in a waveguide mode, and different functional areas of the chip are connected through the mode spot conversion module at the tail end of the waveguide on the chip to achieve low insertion loss. In this implementation, the entire heterogeneous integrated chip is a high-power pulsed laser chip. In this solution, the heterogeneously bonded substrate can also use substrates other than silicon, such as aluminum nitride, aluminum oxide or IIIV substrate wafers.

[0062] In summary, the present invention proposes an all-solid-state pulse laser based on a semiconductor amplifier, including: a laser seed source 1, an isolator 3, a semiconductor amplifier 4, a pulse drive power supply 5, a balanced detector 6, a frequency shifter 7, and a circulator 8.

[0063] The laser seed source 1 emits a stable narrow-linewidth laser signal to the isolator 3. The isolator 3 amplifies the laser after it is emitted, undergoes chopping processing by the semiconductor amplifier 4, and undergoes frequency modulation processing by the frequency shifter 7. Finally, it is output to the subsequent optical transceiver system through the circulator 8 and finally emitted into the atmosphere. The optical transceiver system outputs a returned echo signal to the circulator 8. The circulator 8 outputs the echo signal to the balanced detector 6. The balanced detector 6 performs differential detection on the reference light and the echo signal, and finally converts the optical signal into an electrical signal, which is transmitted to the data processing unit for analysis to measure the wind speed.

[0064] Among them, the semiconductor amplifier 4 is driven by a pulse driving power supply 5. The pulse driving power supply 5 drives the semiconductor amplifier 4 in an extremely short pulse manner to overload it for a short time and output a high-energy pulse laser. The semiconductor amplifier 4 and the pulse driving power supply 5 are completely turned off during non-working hours to reduce energy consumption and heat dissipation requirements, and act as optical switches to chop the laser to form an optical pulse that meets the requirements, replacing the chopping function of the AOM in the current wind measurement radar laser.

[0065] The steps in the present invention can be adjusted in order, combined or deleted according to actual needs.

[0066] The units in the device of the present invention can be combined, divided and deleted according to actual needs.

[0067] Although the present invention is disclosed in detail with reference to the accompanying drawings, it should be understood that these descriptions are merely exemplary and are not intended to limit the application of the present invention. The scope of protection of the present invention is defined by the appended claims and may include various modifications, alterations and equivalents made to the invention without departing from the scope and spirit of the present invention.

Claims

1. All-solid-state pulsed laser based on semiconductor amplifier, characterized in that: The laser comprises: a laser seed source (1), an isolator (3), a semiconductor amplifier (4), a pulse drive power supply (5), a balanced detector (6), a frequency shifter (7), and a circulator (8); The laser seed source (1) emits a stable narrow linewidth laser signal to the isolator (3). The isolator (3) emits the laser, which is amplified by a semiconductor amplifier (4), chopped and frequency modulated by a frequency shifter (7). The laser is finally output to a subsequent optical transceiver system through a circulator (8). The optical transceiver system finally transmits and receives an echo signal to the atmosphere. The optical transceiver system outputs a returned echo signal to the circulator (8). The circulator (8) outputs the echo signal to a balanced detector (6). The balanced detector (6) performs differential detection on the reference light and the echo signal. Finally, the optical signal is converted into an electrical signal, which is transmitted to a data processing unit for analysis to measure the wind speed. The semiconductor amplifier (4) is driven by a pulse drive power supply (5). The pulse drive power supply (5) drives the semiconductor amplifier (4) in an extremely short pulse manner, so that the semiconductor amplifier (4) is overloaded for a short time and outputs high-energy pulse laser. The semiconductor amplifier (4) and the pulse drive power supply (5) are completely turned off during non-working hours to reduce energy consumption and heat dissipation requirements, and play the role of an optical switch to chop the laser, thereby forming an optical pulse that meets the requirements, replacing the chopping function of the AOM in the current wind measurement radar laser.

2. The all-solid-state pulsed laser based on a semiconductor amplifier as claimed in any one of claims 1, characterized in that: The laser also includes: a beam splitter (2); The beam splitter (2) is arranged between the isolator (3) and the semiconductor amplifier (4), and a frequency shifter (7) is arranged behind the semiconductor amplifier (4); the isolator (3) emits laser light to the beam splitter (2), and the beam splitter (2) splits the laser light into two paths, one of which is input to a balanced detector (6) as reference light, and the other of which enters the semiconductor amplifier (4) for amplification and chopping processing.

3. The all-solid-state pulsed laser based on a semiconductor amplifier as claimed in any one of claims 1, characterized in that: The laser seed source (1) is a DBR semiconductor laser chip, and the residual light output by the rear end reflector of the laser seed source (1) is output to a balanced detector (6) as reference light.

4. The all-solid-state pulsed laser based on a semiconductor amplifier as claimed in any one of claims 1, characterized in that: The frequency shifter (7) is arranged between the isolator (3) and the semiconductor amplifier (4). The isolator (3) emits laser light to the frequency shifter (7). The frequency shifter (7) processes the laser light input to the frequency shifter (7) to finally generate frequency shifter output light (72) and frequency shifter residual light (73). The frequency shifter output light (72) is 1st-order or -1st-order diffraction light, and the frequency shifter residual light (73) is residual laser light of 0th-order diffraction. The frequency shifter residual light (73) is input as reference light to the balanced detector (6).

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