High-power narrow-pulse-width dual-wavelength laser based on LED pumping

Abstract

A high-power narrow-pulse-width dual-wavelength laser based on LED pumping comprises a Porro prism, at least two groups of LED pumping modules, a passive Q-switch and an output mirror which are sequentially connected in series. And the Porro prism is used for adjusting and coupling an optical path so as to ensure that an incident light beam enters the system at a proper angle and direction. The main function of the LED array as a pumping source in the laser is to provide excitation energy and excite electrons in the gain medium to transition from a low energy state to a high energy state so as to generate stimulated radiation. When light emitted by the LED irradiates the gain medium, the medium absorbs light energy and enters an excited state, and then laser output is achieved in the resonant cavity through stimulated emission. The inner cavity seed light injection technology combines the advantages of high flexibility, high stability and easy regulation and control, greatly enhances the performance and application range of the dual-wavelength laser, and is particularly prominent in the fields of precision optical application, nonlinear optics and the like.

Description

Technical Field

[0001] The invention relates to the fields of laser technology and optoelectronic technology, and in particular to a high-power narrow-pulse dual-wavelength laser based on LED pumping. Background Art

[0002] It is well known that by controlling the loss of different transition lines in the resonant cavity to meet the threshold condition, the net loss of the gain line in the laser resonant cavity can be balanced, and at this time, it is expected to achieve dual-wavelength laser output simultaneously. The threshold pump power is related to factors such as the reflectivity of the output mirror, the round-trip loss in the cavity, the stimulated emission cross section, and the overlap of the pump light and the oscillation light. Therefore, dual-wavelength laser can be generated simultaneously by controlling the above factors.

[0003] 1. Changing the reflectivity of the output coupling mirror to achieve dual-wavelength laser output: When using output coupling mirror coating to achieve dual-wavelength laser generation, it is necessary to determine the reflectivity of the corresponding output mirror at two wavelengths based on the threshold condition so that their threshold pump powers are similar or equal.

[0004] For example, using Nd:YVO4 (neodymium-doped yttrium vanadate) crystal and electro-optical Q-switched crystal, using output mirror M3 (T 1342nm =0.1) and M4(T 1064nm =0.4) was coated at different wavelengths to obtain a balanced output of dual wavelengths, and the output power at balance was 1.63W.

[0005] 2. Adjust the loss in the resonant cavity: Since the reflectivity of the etalon for different wavelengths is related to the angle θ at which the laser is incident on the etalon, dual-wavelength laser output can be achieved by controlling the loss of different wavelengths in the resonant cavity by changing the incident angle θ.

[0006] For example, by using Nd: YLF (neodymium-doped yttrium lithium fluoride) crystals and acousto-optic Q-switched crystals, active Q-switched dual-wavelength laser output at 1047nm and 1053nm was achieved. When the pump power was 40W and the repetition rate was 30kHz, the maximum average power was 10W; when the repetition rate was 1kHz, the maximum pulse energy was 3.4mJ.

[0007] 3. Using new laser crystal: With the development of laser crystal material technology, some new materials reported in recent years have similar stimulated emission cross sections for different fluorescence transition spectra in certain bands, which can ensure that the threshold pump powers of the two wavelengths are equal or similar, and can be used to simultaneously generate dual-wavelength lasers.

[0008] For example, using Nd: YSAG (neodymium-doped yttrium aluminum yttrium garnet) crystal as the gain medium, dual-wavelength laser output at 1058.97nm and 1061.49nm was achieved.

[0009] Existing technologies have obvious deficiencies in terms of mode competition, power limitation, wavelength controllability, thermal effect, and cost, including the following issues: Mode competition: Mode competition between different wavelengths in the cavity can easily cause unstable output of dual-wavelength lasers; Power limitation: Due to the coupling efficiency limitation of the gain material, high-power dual-wavelength lasers are difficult to achieve; Poor wavelength controllability: In existing designs, the wavelength spacing and adjustable range are limited by the cavity structure and special laser cavity mirror film system; Thermal effect: Under high-density LD pumping conditions, the thermal effect and thermally induced birefringence effect inside the laser crystal will significantly reduce the beam quality, power stability and dual-wavelength output stability; High cost: High-performance pump source LD, precision wavelength tuning components and special laser cavity mirror film systems make the design, manufacturing and maintenance costs high. Summary of the invention

[0010] The present invention provides a dual-wavelength laser with high power and narrow pulse width based on LED pumping. The intracavity seed light injection technology combines the advantages of high flexibility, high stability and easy control, which greatly enhances the performance and application range of the dual-wavelength laser, especially in the fields of precision optical applications and nonlinear optics.

[0011] A dual-wavelength laser with high power and narrow pulse width based on LED pumping comprises a Paul prism, an LED pumping module, a passive Q-switching switch and an output coupling mirror which are connected in series in sequence, wherein the LED pumping modules are at least two groups.

[0012] Furthermore, the Paul prism of the present invention is used for optical path adjustment and coupling to ensure that the incident light beam enters the system at a proper angle and direction.

[0013] Furthermore, the specific structure of the LED pump module of the present invention is as follows: it includes a laser rod located at a central position, a glass sleeve is arranged on the periphery of the laser rod in the length direction, a support frame is arranged on the periphery of the glass sleeve, a plurality of groups of water-cooled copper blocks are evenly arranged on the support frame, an LED stacking array is arranged on one side of each group of water-cooled copper blocks close to the glass sleeve, each LED stacking array includes an LED light bar and a PCB board for fixing the LED light bar, and the PCB board is connected to the water-cooled copper block; Cooling water circulation modules are respectively arranged at both ends of the laser rod in the length direction, and water holes are respectively arranged on the cooling water circulation module and the water-cooled copper block.

[0014] Furthermore, each LED light strip of the present invention includes 20 LED lamp beads forming a row of LED stacked arrays, and the LED lamp beads are SMD LEDs with an emission center wavelength of 810nm, a half-peak width of 30nm, and a beam angle of 90°.

[0015] Furthermore, the operating frequency of the LED of the present invention is 100 Hz, and the pulse duty cycle is 20%.

[0016] Furthermore, the gain medium of the first LED pump module close to the Paul prism of the present invention is neodymium-doped yttrium lithium fluoride; and both ends are sealed in a cooling water circulation module.

[0017] Furthermore, the gain medium of the second LED pump module close to the passive Q-switch of the present invention is neodymium-doped glass, and both ends are sealed in the cooling water circulation module.

[0018] Furthermore, the passive Q-switching switch of the present invention realizes high peak power laser pulse output through temporary storage and release of energy.

[0019] Furthermore, the output coupling mirror of the present invention is used to output dual-wavelength laser.

[0020] The intracavity seed light injection technology combines the advantages of high flexibility, high stability and easy control, greatly enhancing the performance and application range of dual-wavelength lasers, especially in the fields of precision optical applications and nonlinear optics. This method overcomes the limitations of traditional LD-pumped dual-wavelength lasers in wavelength adjustment, mode competition, output stability and cost, showing strong technical application potential and is expected to become a new generation of all-solid-state dual-wavelength laser light sources. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the laser resonant cavity system structure of the present invention.

[0022] Figure 2 It is a cross-sectional schematic diagram of the LED pump module of the present invention.

[0023] Figure 3 It is a schematic longitudinal section diagram of the LED pump module of the present invention. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is described in detail below with reference to the accompanying drawings: like Figure 1 As shown, a dual-wavelength laser with high power and narrow pulse width based on LED pumping is characterized in that it includes a Paul prism 1, an LED pumping module, a passive Q-switching switch 4, and an output coupling mirror 5 which are connected in series in sequence, and the LED pumping module includes a first LED pumping module 2 and a second LED pumping module 3.

[0025] The detailed laser propagation path is shown below: 1. Pump light injection: The LED arrays in the first LED pump module 2 and the second LED pump module 3 emit pump light that vertically enters the gain medium to provide energy therefor, thereby forming a population inversion.

[0026] 2. Generation of initial light: Under the action of pumping, the gain medium begins to generate photons through spontaneous radiation. These photons feed back and forth and oscillate between the Por prism and the output mirror, gradually forming light amplification by stimulated emission.

[0027] 3. Light amplification in the resonant cavity: The photons initially generated are amplified by multiple round trips through the gain medium in the resonant cavity. Each time they pass through the gain medium, the number of photons and the intensity of light increase, gradually forming a high-intensity laser.

[0028] 4.Q-switching process: Passive Q-switched crystals control the energy accumulation and release in the cavity. When enough energy is accumulated, the crystal adjusts the Q value so that the light energy in the laser cavity is output in the form of pulses.

[0029] 5. Laser output: The output coupling mirror allows a portion of the laser energy to be emitted to form a stable laser output beam. After passing through the coupling output mirror, the laser forms a parallel Gaussian beam as the final dual-wavelength laser output.

[0030] like Figure 2 , 3 As shown, the specific structure of the LED pump module of the present invention is as follows: it includes a laser rod 7 located at the center, a glass sleeve 8 is arranged on the periphery of the laser rod 7 in the length direction, a support frame 9 is arranged on the periphery of the glass sleeve 8, a plurality of groups of water-cooled copper blocks 10 are evenly arranged on the support frame 9, an LED stacking array is arranged on one side of each group of water-cooled copper blocks 10 close to the glass sleeve, each LED stacking array includes an LED light bar 11 and a PCB board 12 for fixing the LED light bar, and the PCB board is connected to the water-cooled copper block; Cooling water circulation modules 13 are respectively arranged at both ends of the laser rod in the length direction, and water holes 14 are respectively arranged on the cooling water circulation module 13 and the water-cooled copper block 10 .

[0031] The structural features of the present invention are specifically: 1. Change the film design and structure of the reflector and output coupling mirror to improve the uniformity, standardization and system reliability of the core components of the LED-pumped dual-wavelength laser.

[0032] 1. Significantly improve the uniformity and standardization of the core components of the LED-pumped dual-wavelength laser: In order to allow the two selected wavelengths of laser to oscillate simultaneously in the resonant cavity without interfering with each other, a universal non-customized wavelength bandwidth reflector and an output coupling mirror are selected to form the cavity mirror of the LED-pumped dual-wavelength laser resonant cavity. Figure 1 Paul prism 1 and output coupling mirror 5. The design of cavity mirror film system of traditional LD ​​pumped dual-wavelength laser needs to customize and precisely control the reflectivity of high reflector of each oscillation wavelength and the transmittance of output coupling mirror of each wavelength.

[0033] 2. Improve the tolerance and structural reliability of the overall laser system: Use Por prism to reduce the thermally induced birefringence effect of the laser resonator. In the resonant cavity of the dual-wavelength laser, the Por prism mainly provides a stable beam to correct the optical path deviation and compensate for the thermally induced birefringence inside the crystal through self-alignment, multiple reflections and direction adjustment characteristics, further enhance the intra-cavity mode selection, polarization adjustment and improve the beam quality, while improving the overall tolerance and structural reliability of the laser system.

[0034] 2. Using intracavity seed injection to significantly improve the stability of dual-wavelength laser output and reduce system complexity 1. Reduce mode competition: The seed light provides a clear starting mode in the cavity, significantly reducing the mode competition between different wavelengths and enhancing the stability of dual-wavelength laser synchronous output. In traditional LD ​​pumped lasers, gain competition can cause one wavelength to suppress another wavelength, especially when the gain distribution is uneven.

[0035] 2. Stable output power: Seed light injection can effectively adjust the gain distribution of the laser in the cavity, making the center wavelength and average power of the dual-wavelength laser output more balanced and stable, and not easily affected by external factors. Compared with traditional LD-pumped dual-wavelength lasers, which are easily affected by external factors such as LD temperature drift, cavity vibration, and working environment temperature during operation, it is easy to have the phenomenon of dual-wavelength laser output center wavelength deviation and laser wavelength annihilation, which further affects the output power stability.

[0036] 3. Higher coherence: Seed light injection guides the intracavity oscillation mode, and the output dual-wavelength laser has higher coherence and stability. This has significant advantages in precision applications (such as optical frequency combs or dual-wavelength interferometry). Simple traditional LD-pumped dual-wavelength lasers are difficult to meet the above requirements and require additional frequency-selective devices of various types, which will increase the cost and design difficulty of the laser.

[0037] 4. Simplify laser system design: Seed light injection technology can achieve dual-wavelength laser output through a simple injection light source, avoiding complex intracavity structures or additional wavelength selection devices. Traditional LD-pumped dual-wavelength lasers often require multiple gain media or special resonant cavity structure designs, making the system complex and difficult to adjust.

[0038] 3. Using LED side pumping device can significantly improve the LED pump light coupling efficiency, improve the laser beam quality, increase the working life of the laser system and significantly reduce the cost of the laser system.

[0039] 1. Improve pump light coupling efficiency: The LED side pumping configuration enables the pump light to propagate better in the gain medium. Through side pumping, the pump light can interact with the gain medium over a longer path, improving the absorption efficiency of the LED pump light. This configuration allows the pump light to be more evenly distributed in the gain medium compared to other pumping methods (such as end pumping), thereby improving the coupling efficiency of the pump light.

[0040] 2. Reduce spot distortion: Since the divergence angle of the LED pump light source is large and the incident angle with the gain medium is usually small, the LED side pumping light beam can be evenly distributed on the surface of the gain medium, reducing beam distortion and concentration effects, and helping to improve the beam quality of the laser output.

[0041] 3. Reduce the internal thermal effect of the laser crystal: Since the light source of LED side pumping is widely distributed, it can usually work at a higher power without causing local overheating like end pumping. The lower heat density and uniform pumping method of LED make the thermal management of the overall system more efficient under high-power pumping, significantly reduce the internal thermal effect of the laser crystal, and maintain a longer working life.

[0042] 4. Significantly reduce the cost of the laser system: Under the same output power conditions, the cost of a single LED tube is much lower than that of a single LD tube. At the same time, the supporting system support and protection structure are greatly simplified, and the external power supply adopts a low current and high voltage power supply mode, which significantly reduces the cost of the entire laser system.

[0043] To achieve the above characteristics, the specific structure of each component of the LED-pumped high-power narrow-pulse dual-wavelength laser of the present invention is as follows: 1. Paul prism 1: correspond Figure 1 The blue triangle component on the far left is used for optical path adjustment and coupling to ensure that the incident light beam enters the system at the appropriate angle and direction.

[0044] 2. The first LED pump module 2: The gain medium is a neodymium-doped yttrium lithium fluoride (Nd:YLF) crystal. As a laser medium, after doping with neodymium ions (Nd³⁺), it can achieve light amplification and laser output. It is suitable for higher power output and often works in the near-infrared band.

[0045] Amplification mechanism of Nd:YLF at 1047 nm: Birefringence: Due to its crystal structure, the gain bandwidth of Nd:YLF crystal is separated at 1047 nm and 1053 nm, and π polarization (along the crystal optical axis) selectively amplifies the optical signal with a wavelength of 1047 nm.

[0046] Intracavity feedback: The resonant cavity design ensures that the 1047 nm wavelength light forms a stable oscillation in the cavity, and is further enhanced and amplified by the cavity mirror.

[0047] 3. Second LED pump module 3: The gain medium is a neodymium-doped glass (Nd:glass) crystal. The laser gain characteristics of neodymium-doped glass are similar to those of Nd:YLF, but the material properties are more suitable for short-pulse laser output or certain specific bands.

[0048] Amplification mechanism of Nd:glass at 1053 nm: Wide gain characteristics: The gain center of Nd:glass is at 1053 nm, which can effectively amplify the 1053 nm optical signal.

[0049] Mode separation: The wide gain characteristic makes its gain at 1047 nm weaker, thus reducing the mode interference with Nd:YLF and giving priority to the 1053 nm wavelength.

[0050] 4. Passive Q-switching switch 4: Located behind the gain medium of the second LED pump module 3, it is a small yellow rectangle, such as Figure 1 As shown. Through passive Q-switching technology (the saturable absorber is chromium-doped yttrium aluminum garnet (Cr 4+ :YAG) to achieve laser pulse output. The Q-switching device achieves high peak power laser pulse output by temporarily storing and releasing energy.

[0051] 5. Output coupling mirror 5: Figure 1 The red line in the figure shows the propagation path of the laser. The laser passes through the gain medium and the passive Q-switch in sequence, and then is output through the output mirror.

[0052] The laser of the present invention realizes dual-wavelength laser output in a significant way by intracavity seed light injection, and the output mechanism is: The main function of the LED array as a pump source in the laser is to provide excitation energy to stimulate the photons in the gain medium (such as Nd:YLF and Nd:glass) to transition from a low energy state to a high energy state, thereby generating stimulated radiation. When the light emitted by the LED irradiates the gain medium, the medium absorbs the light energy and enters an excited state, and then realizes laser output through stimulated emission in the resonant cavity.

[0053] Resonant cavity sharing and wavelength selection: Mode selective element: The cavity uses lenses with wavelengths of 1045nm to 1055nm to optimize the feedback paths of 1047nm and 1053nm respectively, ensuring that the two wavelengths oscillate simultaneously without interfering with each other.

[0054] Resonant cavity length matching: The resonant cavity length is precisely controlled to allow the 1047 nm and 1053 nm modes to coexist, forming dual-wavelength output.

[0055] The combined output of dual wavelength light: Due to the uniqueness of the gain medium and the reflective and transmissive film systems coated on the Paul prism 1 and the output coupling mirror 5 at 1045nm~1055nm, the output power and spectral stability of the two-wavelength lasers can be balanced to meet different application requirements.

[0056] This mechanism ensures independent amplification of 1047 nm and 1053 nm while achieving stable resonant output, which is very suitable for high-precision fields requiring dual-wavelength lasers, such as optical measurement, nonlinear conversion, etc.

[0057] Performance Control of Dual-Wavelength Lasers In the laser cavity, a passively Q-switched crystal (usually a saturated absorber such as Cr 4+ :YAG or dye material) is placed in the resonant cavity to suppress and release laser energy. At low light intensity, the passive Q-switched crystal has a high absorption rate and absorbs part of the light in the laser cavity, suppressing the rapid formation of the laser. At high light intensity, when the light intensity in the cavity reaches a certain threshold, the absorption center in the crystal will be "saturated" (that is, the absorption center is excited to a high energy state and can no longer absorb light energy).

[0058] At this time, the transmittance of the passive Q-switched crystal increases significantly, and the energy accumulated in the cavity is released quickly to form a laser pulse with high peak power, while further compressing the laser pulse width.

[0059] Technical effect of the invention: 1. High efficiency and high stability

[0060] a. High efficiency: By injecting seed light into the laser cavity, the wavelength and power of the laser output can be effectively controlled, thereby improving the optical-to-optical conversion efficiency within the overall system. Since the seed light is internally modulated, more efficient energy transfer and change can be performed in the gain medium, effectively reducing the loss of dual-wavelength laser energy.

[0061] b. High stability: Intracavity seed injection can make the output wavelength of LED-pumped dual-wavelength lasers more stable. Compared with multi-mode lasers that directly use spontaneous radiation, intracavity seed injection ensures the single-mode characteristics of laser output and avoids wavelength and power instability caused by mode competition in the laser resonant cavity.

[0062] 2. Accurate laser parameter control

[0063] a. Dual-wavelength laser parameter control: By adjusting the parameters of two seed light sources with different wavelengths (such as power, frequency, wavelength, etc.), the laser can simultaneously generate two specific wavelength outputs. At the same time, it provides precise control and flexible wavelength adjustment, and can also flexibly adjust parameters such as wavelength bandwidth between the two wavelengths to meet different application requirements (such as laser medicine, sensing, material processing, etc.).

[0064] b. Control of intracavity gain mode: The injection of seed light can stabilize the mode in the laser cavity, thereby avoiding irregular wavelength output caused by multiple wavelength resonances. At the same time, the gain mode characteristics in the cavity can be precisely controlled, and the working point of the gain medium can be more accurately selected and optimized. This can make the gain of the gain medium more uniform when exciting different wavelengths. c. Dual-wavelength energy distribution regulation: Intracavity seed injection technology can optimize the amplification effect of the gain medium on the dual-wavelength laser by controlling the power ratio of seed lights of different wavelengths, reduce the competition between the two wavelengths, and ensure the stable output and of the two wavelengths.

[0065] d. Realize dual-wavelength laser synchronous output: Through intracavity seed injection, the synchronization of two wavelength outputs can be achieved. This is very important for some applications (such as dual-wavelength laser sources driving nonlinear optical processes or modulation technologies). The seed-injected external laser source can maintain a stable phase relationship and frequency stability, ensuring the precise synchronous output of dual-wavelength lasers.

[0066] 3. Improve output beam quality

[0067] a. Improve beam quality: Intracavity seed injection can effectively control the laser mode, thereby providing better beam quality. Since the wavefront of the seed light has been precisely controlled, after entering the laser cavity, the output laser beam can maintain good focusing characteristics, reducing beam distortion caused by non-ideal optical modes.

[0068] b. Multimode laser optimization: Dual-wavelength laser output usually requires the beam to maintain high optical quality at both wavelengths. Intracavity seed injection can help the laser system optimize the output beam mode and avoid mode competition and beam quality degradation that may occur in traditional multimode lasers.

[0069] 4. Reduce system complexity and improve system reliability

[0070] a. Save space and reduce the number of components: The intracavity seed injection system can integrate the seed light source directly into the laser cavity, without the need for external complex optical adjustment systems or multiple pump light sources. This simplifies system design, reduces the use of external components, and reduces the size and cost of the system.

[0071] b. Improve the reliability of the overall system: Intracavity seed injection technology converts the output of multiple wavelengths into the same laser cavity to achieve dual-wavelength or multi-wavelength output, reducing the errors and unstable factors introduced by multiple laser sources and optical paths, and improving the reliability of the entire laser system.

[0072] 5. Widely used

[0073] a. Nonlinear frequency conversion: Dual-wavelength lasers with intracavity seed injection are very suitable for nonlinear frequency conversion processes, such as optical parametric amplification (OPA), optical parametric oscillation (OPO), etc. These processes require laser sources with different wavelengths to achieve efficient frequency conversion and generate new wavelengths of laser light.

[0074] b. Application of dual-wavelength laser sources: In some specific scientific research, industry, medical and other fields, dual-wavelength lasers can provide specific wavelength combinations to meet different needs. For example, some biomedical imaging technologies, laser differential radar (LiDAR) or environmental monitoring require lasers of different wavelengths for multi-angle or multi-wavelength data collection, and they are also important fundamental frequency light sources for generating THz sources.

[0075] A dual-wavelength laser based on LED pumping, high-power, narrow-pulse width, using intracavity seed injection technology and Q-switching technology, can provide efficient and stable dual-wavelength laser output. This method can not only improve the efficiency of light-to-light conversion, enhance the accuracy of wavelength control and compress pulse width, but also improve the beam quality to a certain extent, reduce the complexity of the system, and improve the uniformity and standardization of the core components of the laser system. It shows strong technical application potential in scientific research, industry, medical treatment and other fields, and is expected to become a new generation of all-solid-state dual-wavelength laser light source, while filling the gap in domestic and foreign research fields.

Claims

1. A dual-wavelength laser based on LED pumping high power narrow pulse width, characterized in that It comprises a Paul prism, an LED pump module, a passive Q-switching switch and an output coupling mirror which are connected in series in sequence, wherein the LED pump module is in at least two groups.

2. The high-power narrow-pulse dual-wavelength laser based on LED pumping according to claim 1, characterized in that The above-mentioned Porro prism is used for optical path adjustment and coupling to ensure that the incident light beam enters the system at the appropriate angle and direction.

3. The LED-pumped high-power narrow-pulse dual-wavelength laser according to claim 1, characterized in that The specific structure of the above LED pump module is as follows: it includes a laser rod located at the center, a glass sleeve is arranged on the periphery of the laser rod in the length direction, a support frame is arranged on the periphery of the glass sleeve, a plurality of groups of water-cooled copper blocks are evenly arranged on the support frame, an LED stacking array is arranged on one side of each group of water-cooled copper blocks close to the glass sleeve, each LED stacking array includes an LED light bar and a PCB board for fixing the LED light bar, and the PCB board is connected to the water-cooled copper block; Cooling water circulation modules are respectively arranged at both ends of the laser rod in the length direction, and water holes are respectively arranged on the cooling water circulation module and the water-cooled copper block.

4. The LED-pumped high-power narrow-pulse dual-wavelength laser according to claim 3, characterized in that Each of the above-mentioned LED light strips includes 20 LED lamp beads to form a row of LED stacked arrays. The LED lamp beads are surface-mount LEDs with an emission center wavelength of 810nm, a half-peak width of 30nm, and a beam angle of 90°.

5. The LED-pumped high-power narrow-pulse dual-wavelength laser according to claim 4, characterized in that The operating frequency of the above LED is 100 Hz, and the pulse duty cycle is 20%.

6. The LED-pumped high-power narrow-pulse dual-wavelength laser according to claim 3, characterized in that The gain medium of the first LED pump module close to the Paul prism is neodymium-doped yttrium fluoride lithium; both ends are sealed in a cooling water circulation module.

7. The LED-pumped high-power narrow-pulse dual-wavelength laser according to claim 3, characterized in that The gain medium of the second LED pump module close to the passive Q-switch is neodymium-doped glass, and both ends are sealed in a cooling water circulation module.

8. The LED-pumped high-power narrow-pulse dual-wavelength laser according to claim 1, characterized in that The passive Q-switching switch described above realizes high peak power laser pulse output by temporarily storing and releasing energy.

9. The LED-pumped high-power narrow-pulse dual-wavelength laser according to claim 1, characterized in that The output coupling mirror is used to output laser light.

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