A kind of all-solid-state ultraviolet laser for ozone detection while generating 310nm and 355nm high-energy laser

Abstract

The application discloses a kind of simultaneously generating 310nm and 355nm high-energy laser full solid-state ultraviolet laser, belongs to the technical field of laser.The frequency-doubled module of fundamental laser and it, intracavity sum-frequency module of optical parametric oscillator, sum-frequency module three parts, make full use of the output energy of 1064nm pulsed laser, adopt frequency conversion technology such as frequency doubling, optical parametric oscillation, sum-frequency, realize 310nm and 355nm ultraviolet pulsed laser output.The application has the advantages of multi-wavelength, high energy, high beam quality, compact structure, and the ultraviolet band is in ozone absorption band, especially suitable for the detection of troposphere and stratosphere atmospheric ozone concentration by spaceborne laser radar.

Description

Technical Field

[0001] The invention belongs to the technical field of lasers, and mainly relates to a method for developing an all-solid-state ultraviolet laser that can simultaneously generate 310nm and 355nm high-energy lasers. Background Art

[0002] Ozone, a pale blue gas with a distinctive odor, was discovered by German scientist C.F. Schonbein in the 1840s. Its active chemical properties allow it to participate in a variety of atmospheric photochemical reactions. Atmospheric ozone is typically found in the stratosphere and troposphere, with approximately 90% of ozone distributed in the stratosphere at an altitude of 10-50 km and 10% in the troposphere below 10 km. Ozone plays a vital role in human health, plant growth, climate regulation, and maintaining Earth's radiation balance. As a trace gas in the atmosphere, ozone absorbs the vast majority of short-wavelength ultraviolet rays in sunlight, protecting life on Earth from harmful ultraviolet radiation. It plays a vital role in the regional and global atmosphere and climate systems.

[0003] Differential absorption lidar (DIAL) is an effective active remote sensing method for detecting the vertical distribution of atmospheric ozone. Its advantages are mainly high spatial resolution and temporal resolution, and the ability to conduct real-time vertical observation and continuous long-term observation. One of the core issues in the research of differential absorption lidar technology is the use of different emission light source technology to obtain lasers of different wavelengths to detect different or the same pollutants. In order to detect stratospheric ozone, it is important to develop ultraviolet band light sources in combination with ozone absorption spectra. The present invention designs and develops an all-solid-state ultraviolet laser that can simultaneously generate 310nm and 355nm high-energy lasers in response to the needs of lidar ozone detection.

[0004] There are several main light source technologies for the development of ultraviolet differential absorption lidar light sources. The XeCl excimer laser emits 308nm laser light, but the excimer laser is inefficient, expensive, and contains toxic gases. The titanium sapphire laser is a tunable laser with a wide tuning range. It can be tuned within the range of 700-1050nm. When combined with nonlinear frequency conversion technology, the band can be extended to the ultraviolet. Raman lasers use stimulated Raman scattering technology to convert the wavelength of lasers, which can extend the laser wavelength. These technologies include gas Raman technology, liquid Raman technology, and solid Raman technology. Gas and liquid Raman technologies have disadvantages such as large equipment size, low conversion efficiency, and poor beam quality. Therefore, solid Raman technology has great development potential in wavelength conversion. Patent CN219715757U describes a method for frequency up-conversion based on stimulated Raman scattering, followed by frequency doubling to achieve dual-wavelength ultraviolet laser output of 280nm and 295nm. However, stimulated Raman scattering is inelastic, and during the scattering process, some energy is stored as heat in the Raman crystal. The absorption of pump light by the Raman crystal also generates heat, which can lead to self-focusing and thermally induced birefringence in the Raman crystal, ultimately resulting in unstable power and low efficiency of the output Raman laser. Optical parametric oscillation (OPO) technology is a mature nonlinear frequency conversion technology that, combined with frequency doubling and sum frequency techniques, can flexibly extend the laser wavelength into the ultraviolet to meet various detection needs. Patent CN 111725695A describes a method for generating a 1064nm Nd:YAG Q-switched laser as a pump source to pump an optical parametric oscillator (OPO). This method also uses frequency doubling and tripling techniques to generate a 355nm laser. This 355nm laser is then summed with the OPO output signal light to achieve a 289nm / 299nm laser output. However, due to the excessive nonlinear frequency conversion involved in this process, the overall conversion efficiency is low, and the laser wavelengths generated are at 289nm and 299nm, which fails to address the large ozone absorption cross-section. Patent CN 116565681A describes a method for generating a 193nm vacuum ultraviolet laser output. This scheme uses a 355nm laser generated by tripling the fundamental frequency of a 1064nm pulse to pump an OPO to generate a 472nm signal light. The resulting frequency-doubled light is then summed with the 1064nm fundamental frequency light to produce the vacuum ultraviolet output. This method is used to generate vacuum ultraviolet light output between 100-200nm and is not suitable for ozone detection.

[0005] Currently, there are no reports of solid-state gain media that can directly generate ultraviolet laser light. Therefore, the main method for generating ultraviolet laser light currently relies on nonlinear harmonic conversion technology. Among the development of ultraviolet light sources using nonlinear harmonic conversion technology, there are no reports of developing laser sources at 310nm. To meet the needs of spaceborne applications, this invention uses optical parametric oscillation technology combined with frequency doubling and sum frequency technology to frequency convert 1064nm fundamental frequency light, ultimately achieving 310nm and 355nm high-power pulsed laser output, addressing the need for a transmitting light source for lidar ozone detection. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the present invention proposes to design an all-solid-state ultraviolet laser that can simultaneously generate 310nm and 355nm high-energy lasers, providing a high-energy, high-beam-quality ultraviolet light source for lidar ozone detection.

[0007] The technical solution of the present invention is:

[0008] A fully solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers. The present invention also provides a method for constructing the above-mentioned laser structure, which is characterized in that it includes three parts: a fundamental frequency laser and its frequency doubling module, an optical parametric oscillator intracavity sum frequency module, and a sum frequency module: a 1064nm single-frequency pulse laser is amplified and frequency-doubled to generate a 532nm pulse laser, a 532nm pulse laser is pumped by an optical parametric oscillator (OPO) to generate a 743nm signal light, and the OPO cavity adopts an intracavity sum frequency four-crystal non-planar image rotating ring cavity design. By rotating the image, the birefringence walk-off of the light beam in the crystal is expanded from one dimension to two lateral directions. The spatial coherence of the light beam is increased through multiple cycles of oscillation in the cavity. At the same time, four crystals are used to perform parameter conversion and sum frequency conversion on the four axes of the optical parametric oscillator, shortening the cavity length while lowering the threshold, improving the beam quality and conversion efficiency of the 310nm sum frequency light output by the OPO. The remaining 532nm pulsed laser pump light and the remaining 1064nm pulsed laser are used to generate 355nm pulsed laser through the sum frequency module. The specific structure is as follows:

[0009] The 1064nm single-frequency pulse seed laser is amplified by the laser amplification module to form a 1064nm fundamental frequency laser. After the polarization state of the 1064nm fundamental frequency laser is adjusted by the first half-wave plate, the frequency is converted by the frequency doubling crystal. A portion of the 1064nm fundamental frequency laser is converted into a 532nm frequency-doubled laser, which is reflected by the first reflector into the first beam splitter. The remaining 1064nm fundamental frequency laser in the frequency doubling process is reflected and output by the first beam splitter. The 532nm frequency-doubled laser transmits the first beam splitter into the second half-wave plate. After the polarization state is adjusted by the second half-wave plate, it is reflected by the second reflector into the sum frequency module in the optical parametric oscillator cavity.

[0010] The optical parametric oscillator module includes a first parametric cavity mirror, a first parametric crystal, a second parametric cavity mirror, a third half-wave plate, a first sum frequency crystal, a third parametric cavity mirror, a second parametric crystal, a fourth parametric cavity mirror, a second sum frequency crystal, a fourth half-wave plate, a second beam splitter, a third reflector, a fifth half-wave plate, and a first beam combiner. The first parametric crystal is arranged between the first parametric cavity mirror and the second parametric cavity mirror, the third half-wave plate and the first sum frequency crystal are arranged between the second parametric cavity mirror and the third parametric cavity mirror, the second parametric crystal is arranged between the third parametric cavity mirror and the fourth parametric cavity mirror, and the second sum frequency crystal and the fourth half-wave plate are arranged between the fourth parametric cavity mirror and the first parametric cavity mirror.

[0011] The parametric pump light is transmitted through the first parametric cavity mirror into the optical parametric oscillator, and is converted by the first parametric crystal to generate 743nm signal light and 1873.3nm idler light. The second parametric cavity mirror transmits the 1873.3nm idler light, reflects the 743nm signal light and 532nm pump light, adjusts the polarization state through the third half-wave plate, enters the first sum frequency crystal for sum frequency generation, and generates 310nm sum frequency light. The remaining 532nm pump light is reflected by the third parametric cavity mirror and enters the second parametric crystal for further conversion to generate 743nm signal light and 1873.3nm idler light. The idler light, 1873.3nm idler light is transmitted and output through the third parametric cavity mirror, the 532nm pump light and 743nm signal light are reflected into the second sum frequency crystal for further conversion to generate 310nm sum frequency light, which is polarization-adjusted by the fourth half-wave plate and then transmitted and output through the first parametric cavity mirror. The 310nm sum frequency light is transmitted and output through the second beam splitter, and the remaining 532nm pump light is reflected by the third reflector and then enters the fifth half-wave plate for polarization adjustment. After being reflected by the first beam combiner, it is combined with the 1064nm fundamental frequency laser and output into the sum frequency module.

[0012] The sum frequency module receives the remaining 1064nm fundamental frequency laser and the remaining parametric pump light and transmits them to the third sum frequency crystal and the fourth sum frequency crystal for frequency conversion. A portion of the light is converted into a 355nm ultraviolet pulse laser and outputted through the third spectroscope. The remaining 1064nm fundamental frequency laser and the 532nm pump light are reflected and outputted through the third spectroscope.

[0013] Furthermore, the laser amplification module includes an 808nm LD pump source and several amplifying crystals. The 1064nm single-frequency pulse seed laser is double-pass amplified by the end-face LD-pumped Nd:YVO4 crystal, then double-pass amplified by the side LD-pumped Nd:YAG crystal, and finally power-amplified by the double-sided LD-pumped Nd:YAG crystal to form a 1064nm fundamental frequency laser.

[0014] Furthermore, the first half-wave plate is a 1064nm half-wave plate; the third half-wave plate is a dual-wavelength half-wave plate of 532nm and 743nm; the fourth half-wave plate is a 743nm half-wave plate; the second half-wave plate and the fifth half-wave plate are 532nm half-wave plates.

[0015] Furthermore, the first parametric cavity mirror is coated with a 532nm anti-reflection film, a 310nm anti-reflection film and a 743nm high-reflection film; the second parametric cavity mirror is coated with a 532nm high-reflection film, a 743nm high-reflection film and a 1873.3nm anti-reflection film; the third parametric cavity mirror is coated with a 532nm high-reflection film, a 743nm high-reflection film and a 310nm high-reflection film; the fourth parametric cavity mirror is coated with a 532nm high-reflection film, a 743nm high-reflection film, a 310nm high-reflection film and a 1873.3nm anti-reflection film; the coating angles of the parametric cavity mirrors are all 32.8°.

[0016] Furthermore, the first beam splitter is coated with a 45° 1064nm high reflection film and a 532nm anti-reflection film; the second beam splitter is coated with a 45° 532nm high reflection film and a 310nm anti-reflection film; the third beam splitter is coated with a 45° 532nm high reflection film, a 1064nm high reflection film and a 355nm anti-reflection film.

[0017] Furthermore, the frequency doubling crystal is a type I phase-matched LBO crystal, the first parametric crystal and the second parametric crystal are type I phase-matched BBO crystals, the first sum frequency crystal and the second sum frequency crystal are type I phase-matched LBO crystals, and the third sum frequency crystal and the fourth sum frequency crystal are type I phase-matched LBO crystals; the first parametric crystal and the second parametric crystal are synchronously placed according to the polarization state direction of the rotating intra-cavity pump light, the first sum frequency crystal and the second sum frequency crystal are placed in the cavity for walk-off compensation according to the polarization state direction of the 532nm pump light and the 743nm signal light, and the third sum frequency crystal and the fourth sum frequency crystal are placed for walk-off compensation according to the polarization state direction of the remaining 532nm pump light and the 1064nm fundamental frequency light.

[0018] The present invention has the following advantages:

[0019] 1. A set of lasers can simultaneously output two different pulse lasers of 310nm and 355nm, meeting the light source requirements of lidar atmospheric ozone detection.

[0020] 2. An intra-cavity sum frequency four-crystal non-planar image rotating annular cavity was designed. Four crystals were placed on the major axis and minor axis respectively, which greatly shortened the cavity length, made the overall structure compact, reduced losses, and improved the conversion efficiency of the OPO.

[0021] 3. The placement of the parametric crystal utilizes the walk-off effect and non-planar image rotation cavity to improve the signal light beam quality, and the sum frequency crystal is placed for walk-off compensation to improve the conversion efficiency.

[0022] 4. Utilize the high power density of the intracavity signal light to perform intracavity sum frequency technology to obtain high-efficiency 310nm pulsed laser output.

[0023] 5. The remaining 1064nm pulse laser after the 1064nm fundamental frequency light is frequency-doubled and the remaining 532nm pump light of the OPO is used to achieve 355nm pulse laser output through frequency summing technology, avoiding energy waste and improving energy utilization efficiency.

[0024] 6. The overall laser design has a simple and compact structure, high conversion efficiency, high output pulse energy, and is suitable for practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a schematic structural diagram of an all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers.

[0026] Figure 2 This is a diagram of the structure of the non-planar image rotating annular cavity with four crystals in the cavity. DETAILED DESCRIPTION

[0027] The following is combined with Figure 1 , Attachment Figure 2 , a complete description of the specific technical solutions in the embodiments of the present invention is given. The technical solutions and parameters described in the embodiments of the present invention are only part of the present invention. All other embodiments based on the embodiments of the present invention are within the scope of protection of the present invention without making creative improvements and inventions.

[0028] Figure 1 This is a structural diagram of an all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers according to the present invention. Figure 1 As shown, the present invention is an all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers, including three parts: a fundamental frequency laser and its frequency doubling module 1, an optical parametric oscillator intracavity sum frequency module 2, and a sum frequency module 3.

[0029] The fundamental frequency laser and its frequency doubling module 1 are used to generate 1064nm pulsed laser to be incident on the sum frequency module 3, and at the same time generate 532nm pulsed laser to be incident on the sum frequency module 2 in the optical parametric oscillator cavity. The sum frequency module 2 in the optical parametric oscillator cavity is used to receive the 532nm pulsed laser and generate 743nm pulsed laser through parametric conversion, and generate 310nm pulsed laser through intracavity sum frequency. The sum frequency module 3 is used to receive the 1064nm pulsed laser and the 532nm pulsed laser and generate 355nm pulsed laser through sum frequency.

[0030] In this example, the 1064nm seed laser 1-1 in the fundamental frequency laser and its frequency doubling module 1 is used to generate a 1064nm single-frequency pulse seed laser, which is amplified by the laser amplification module 1-2 to form a 1064nm fundamental frequency laser with a pulse width of 10ns. The polarization state of the 1064nm fundamental frequency laser is adjusted by the first half-wave plate 1-3, and the frequency is converted by the frequency doubling crystal 1-4. A part of the 1064nm fundamental frequency laser is converted into a 532nm frequency doubling laser, which is reflected by the first reflector 1-5 and enters the first beam splitter 1-6. The remaining 1064nm fundamental frequency laser is reflected and output by the first beam splitter 1-6. The 532nm frequency doubling laser is transmitted through the first beam splitter 1-6 and enters the second half-wave plate 1-7. After the polarization state is adjusted by the second half-wave plate 1-7, it is reflected by the second reflector 1-8 and enters the optical parametric oscillator cavity and the frequency module 2.

[0031] The first half-wave plate 1-3 is a 1064nm half-wave plate, the surface of which is coated with a 1064nm anti-reflection film; the frequency doubling crystal 1-4 is an LBO crystal, which adopts type I critical phase matching and has a cutting angle of θ=90.0°. The crystal end faces are coated with 1064nm and 532nm anti-reflection coatings; the first reflectors 1-5 are coated with 45° high-reflection coatings for 532nm and 1064nm wavelengths; the first beam splitters 1-6 are coated with 45° anti-reflection coatings for 532nm and 1064nm wavelengths; the second half-wave plates 1-7 are 532nm half-wave plates, the surfaces of which are coated with 532nm anti-reflection coatings; the second reflectors 1-8 are coated with 45° high-reflection coatings for 532nm; the laser amplification module includes an 808nm LD pump source and several amplifying crystals; the 1064nm single-frequency pulse seed laser is double-pass amplified by an Nd:YVO4 crystal pumped by an end-face LD, then double-pass amplified by an Nd:YAG crystal pumped by a side LD, and finally power amplified by an Nd:YAG crystal pumped by a double-sided LD to form a 1064nm fundamental frequency laser.

[0032] In this example, the optical parametric oscillator intracavity sum frequency module 2 includes a first parametric cavity mirror 2-1, a first parametric crystal 2-2, a second parametric cavity mirror 2-3, a third half-wave plate 2-4, a first sum frequency crystal 2-5, a third parametric cavity mirror 2-6, a second parametric crystal 2-7, a fourth parametric cavity mirror 2-8, a second sum frequency crystal 2-9, a fourth half-wave plate 2-10, a second beam splitter 2-11, a third reflector 2-12, a fifth half-wave plate 2-13, and a first beam combiner 2-14. The first parametric crystal 2-2 is arranged between the first parametric cavity mirror 2-1 and the second parametric cavity mirror 2-3, the third half-wave plate 2-4 and the first sum frequency crystal 2-5 are arranged between the second parametric cavity mirror 2-3 and the third parametric cavity mirror 2-6, the second parametric crystal 2-7 is arranged between the third parametric cavity mirror 2-6 and the fourth parametric cavity mirror 2-8, and the second sum frequency crystal 2-9 and the fourth half-wave plate 2-10 are arranged between the fourth parametric cavity mirror 2-8 and the first parametric cavity mirror 2-1.

[0033] The optical parametric oscillator of this embodiment is an intracavity sum frequency four-crystal non-planar image rotating ring cavity structure, and its three-dimensional structure is as follows: Figure 2 shown.

[0034] In this example, the parametric pump light is transmitted through the first parametric cavity mirror 2-1 into the optical parametric oscillator, and is converted by the first parametric crystal 2-2 to generate signal light and idler light. The second parametric cavity mirror 2-3 transmits the idler light, and the reflected signal light and pump light are adjusted in polarization state by the third half-wave plate 2-4 and enter the first sum frequency crystal 2-5. The pump light and the signal light are sum-frequency-transduced to generate sum-frequency light. The remaining parametric pump light passes through the third parametric cavity mirror 2-6 and enters the second parametric crystal 2-7 to continue to convert to generate signal light and idler light. The idler light The light is transmitted through the third parametric cavity mirror 2-8, and the sum frequency light, pump light and signal light are reflected into the second sum frequency crystal 2-9 for further conversion to generate sum frequency light. After the polarization state is adjusted by the fourth half-wave plate 2-10, it is transmitted and outputted from the first parametric cavity mirror 2-1. The sum frequency light is transmitted and outputted from the second beam splitter 2-11. The pump light is reflected by the third reflector 2-12 and then enters the fifth half-wave plate 2-13 for polarization state adjustment. After being reflected by the first beam combiner 2-14, it is combined with the baseband laser and outputted into the sum frequency module 3.

[0035] The first parameter crystal 2-2 and the second parameter crystal 2-7 are BBO crystals, the crystals adopt type I critical phase matching, and the cutting angle is θ=21.6°. The end face of the first parameter crystal 2-2 is coated with an anti-reflection film of 532nm, 743nm, and 1873.3nm, and the end face of the second parameter crystal 2-7 is coated with an anti-reflection film of 310nm, 532nm, 743nm, and 1873.3nm; the first sum frequency crystal 2-5 and the second sum frequency crystal 2-9 are LBO crystals, and the crystals adopt type I critical phase matching, and the cutting angle is θ=90°. The end faces of the first sum frequency crystal 2-5 and the second sum frequency crystal 2-9 are coated with 532nm, 743nm, and 310nm anti-reflection films; the first parametric crystal 2-2 and the second parametric crystal 2-7 are placed synchronously according to the polarization state direction of the rotating pump light in the cavity, and the first sum frequency crystal 2-5 and the second sum frequency crystal 2-9 are placed in the cavity for walk-off compensation according to the polarization state direction of the 532nm pump light and the 743nm signal light.

[0036] The first parametric cavity mirror 2-1 is coated with a 32.8° anti-reflection film with a wavelength of 310nm, a 32.8° anti-reflection film with a wavelength of 532nm, and a 32.8° high-reflection film with a wavelength of 743nm; the second parametric cavity mirror 2-3 is coated with a 32.8° high-reflection film with a wavelength of 532nm, a 32.8° high-reflection film with a wavelength of 743nm, and a 32.8° anti-reflection film with a wavelength of 1873.3nm; the third parametric cavity mirror 2-6 is coated with a 32.8° high-reflection film with wavelengths of 310nm, 532nm and 743nm; the fourth parametric cavity mirror 2-8 is coated with a 32.8° high-reflection film with wavelengths of 310nm, 532nm and 743nm, and a 32.8° anti-reflection film with a wavelength of 1873.3nm.

[0037] The third half-wave plate 2-4 is a dual-wavelength half-wave plate of 532nm and 743nm, and its surface is coated with 532nm and 743nm anti-reflection coatings; the fourth half-wave plate 2-10 is a 743nm half-wave plate, and its surface is coated with a 743nm anti-reflection coating; the second beam splitter 2-11 is coated with a 45° high-reflection coating of 532nm wavelength and a 45° anti-reflection coating of 1873.3nm wavelength; the third reflector 2-12 is coated with a 45° high-reflection coating of 532nm wavelength; the fifth half-wave plate 2-13 is a 532nm half-wave plate, and its surface is coated with a 532nm anti-reflection coating; the first beam combiner 2-14 is coated with a 45° anti-reflection coating of 1064nm wavelength and a 45° high-reflection coating of 532nm wavelength.

[0038] In this example, the sum frequency module 3 receives the remaining 1064nm fundamental frequency laser and the remaining parametric pump light and inputs them into the third sum frequency crystal 3-1 and the fourth sum frequency crystal 3-2 for frequency conversion. A portion of the light is converted into a 355nm ultraviolet pulsed laser and outputted through the third beam splitter 3-3, and the remaining 1064nm fundamental frequency laser and 532nm parametric pump light are reflected and outputted through the third beam splitter 3-3.

[0039] The third sum frequency crystal 3-1 and the fourth sum frequency crystal 3-2 are LBO crystals, which adopt type I critical phase matching and have a cutting angle of θ=90°. The crystal end faces are coated with 355nm, 532nm, and 1064nm anti-reflection films, and the third and fourth sum frequency crystals 3-1 and 3-2 are placed for walk-off compensation; the surface of the third beam splitter 3-3 is coated with a 45° high-reflection film for 1064nm and 532nm wavelengths and a 45° anti-reflection film for 355nm wavelength.

[0040] The embodiments described above are only preferred specific implementation methods of the present invention, and the scope of protection of the present invention is not limited thereto. Any simple change or equivalent replacement of the technical solution that can be obviously obtained by any technician familiar with the field within the technical scope disclosed in the present invention, or various other corresponding changes and deformations made based on the technical concept of the present invention all fall within the scope of protection of the present invention.

Claims

1. An all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers, characterized in that: The invention comprises three parts: a fundamental frequency laser and its frequency doubling module (1), an optical parametric oscillator intra-cavity sum frequency module (2), and a sum frequency module (3): a 1064nm single-frequency pulse laser is amplified and frequency-doubled to generate a 532nm pulse laser; the 532nm pulse laser is used to pump an optical parametric oscillator (OPO); the OPO output signal light and the 532nm pulse laser are sum-frequencyed in the cavity to generate a 310nm pulse laser; the remaining 532nm pulse laser pump light and the remaining 1064nm pulse laser are combined with the sum frequency module (3) to generate a 355nm pulse laser; The fundamental frequency laser and its frequency doubling module (1) include a 1064nm seed laser (1-1), a laser amplifying module (1-2), a first half-wave plate (1-3), a frequency doubling crystal (1-4), a first reflector (1-5), a first beam splitter (1-6), a second half-wave plate (1-7), and a second reflector (1-8). The 1064nm single-frequency pulse seed laser generated by the 1064nm seed laser (1-1) is amplified by the laser amplifying module (1-2) to form a 1064nm fundamental frequency laser. The 1064nm fundamental frequency laser is amplified by the first half-wave plate (1-3), a frequency doubling crystal (1-4), a first reflector (1-5), a first beam splitter (1-6), a second half-wave plate (1-7), and a second reflector (1-8). The plate (1-3) adjusts the polarization state and performs frequency conversion via the frequency doubling crystal (1-4). A portion of the 1064nm fundamental frequency laser is converted into a 532nm frequency doubling laser, which is reflected by the first reflector (1-5) and enters the first beam splitter (1-6). The remaining 1064nm fundamental frequency laser is reflected and outputted via the first beam splitter (1-6). The 532nm frequency doubling laser is transmitted through the first beam splitter (1-6) and enters the second half-wave plate (1-7). After the polarization state is adjusted by the second half-wave plate (1-7), the laser is reflected and outputted by the second reflector (1-8) to form parametric pump light. The optical parametric oscillator intracavity sum frequency module (2) comprises a first parametric cavity mirror (2-1), a first parametric crystal (2-2), a second parametric cavity mirror (2-3), a third half-wave plate (2-4), a first sum frequency crystal (2-5), a third parametric cavity mirror (2-6), a second parametric crystal (2-7), a fourth parametric cavity mirror (2-8), a second sum frequency crystal (2-9), a fourth half-wave plate (2-10), a second beam splitter (2-11), a third reflector (2-12), a fifth half-wave plate (2-13), a first beam combiner (2-14), the first parametric crystal (2-2) being arranged between the first parametric cavity mirror (2-1) and the second parametric cavity mirror (2-3), the ...5), a second half-wave plate (2-6), a second half-wave plate (2-7), a fourth parametric cavity mirror (2-8), a second sum frequency crystal (2-9), a fourth half-wave plate (2-10), a second beam splitter (2-11), a third reflector (2-12), a fifth half-wave plate (2-13), a first beam combiner (2-14), -4) and the first sum frequency crystal (2-5) are arranged between the second parametric cavity mirror (2-3) and the third parametric cavity mirror (2-6), the second parametric crystal (2-7) is arranged between the third parametric cavity mirror (2-6) and the fourth parametric cavity mirror (2-8), the second sum frequency crystal (2-9) and the fourth half-wave plate (2-10) are arranged between the fourth parametric cavity mirror (2-8) and the first parametric cavity mirror (2-1), the first parametric crystal (2-2) and the second parametric crystal (2-7) are synchronously placed according to the rotating cavity to adjust the polarization state direction of the pump light, and the first sum frequency crystal (2-5) and the second sum frequency crystal (2-9) are placed according to the polarization state directions of the pump light and the signal light for walk-off compensation; The parametric pump light is transmitted through the first parametric cavity mirror (2-1) into the optical parametric oscillator, and is converted by the first parametric crystal (2-2) to generate signal light and idler light. The second parametric cavity mirror (2-3) transmits the idler light, and the reflected signal light and pump light are adjusted in polarization state through the third half-wave plate (2-4) and enter the first sum frequency crystal (2-5). The pump light and the signal light are sum-frequency-transduced to generate sum frequency light. The remaining parametric pump light passes through the third parametric cavity mirror (2-6) and enters the second parametric crystal (2-7) to continue to convert to generate signal light and idler light. The idler light transmits the fourth parametric cavity mirror (2-8). The cavity mirror (2-8) is used for the pump light and the signal light to be reflected and enter the second sum frequency crystal (2-9) for further conversion to generate sum frequency light. After the polarization state is adjusted by the fourth half-wave plate (2-10), the sum frequency light is transmitted and outputted through the first parametric cavity mirror (2-1). The sum frequency light is transmitted and outputted through the second beam splitter (2-11). The pump light is reflected and enters the fifth half-wave plate (2-13) for polarization state adjustment after being reflected by the third reflector (2-12). After being reflected by the first beam combiner (2-14), the pump light is combined with the fundamental frequency laser reflected by the first beam splitter (1-6) and outputted into the sum frequency module (3). The sum frequency module (3) includes a third sum frequency crystal (3-1), a fourth sum frequency crystal (3-2) and a third beam splitter (3-3). The remaining 1064nm fundamental frequency laser and the remaining parametric pump light outputted by the first beam combiner (2-14) are incident on the third sum frequency crystal (3-1) and the fourth sum frequency crystal (3-2) for frequency conversion. A portion of the laser light is converted into a 355nm ultraviolet pulse laser and transmitted and outputted through the third beam splitter (3-3). The remaining 1064nm fundamental frequency laser and the 532nm parametric pump light are reflected and outputted through the third beam splitter (3-3). The third sum frequency crystal (3-1) and the fourth sum frequency crystal (3-2) are placed for walk-off compensation according to the polarization state directions of the fundamental frequency light and the remaining pump light.

2. The all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers according to claim 1, characterized in that: The first half-wave plate (1-3) is a 1064nm half-wave plate; the third half-wave plate (2-4) is a dual-wavelength half-wave plate of 532nm and 743nm; the fourth half-wave plate (2-10) is a 743nm half-wave plate, and the second half-wave plate (1-7) and the fifth half-wave plate (2-13) are 532nm half-wave plates.

3. The all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers according to claim 1, characterized in that: The first parametric cavity mirror (2-1) is coated with a 532nm anti-reflection film, a 310nm anti-reflection film and a 743nm high-reflection film; the second parametric cavity mirror (2-3) is coated with a 532nm high-reflection film, a 743nm high-reflection film and an 1873.3nm anti-reflection film; the third parametric cavity mirror (2-6) is coated with a 532nm high-reflection film, a 743nm high-reflection film and a 310nm high-reflection film; the fourth parametric cavity mirror (2-8) is coated with a 532nm high-reflection film, a 743nm high-reflection film, a 310nm high-reflection film and an 1873.3nm anti-reflection film; and the coating angles of the parametric cavity mirrors are all 32.8°.

4. The all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers according to claim 1, characterized in that: The first beam splitter (1-6) is coated with a 45° 1064nm high-reflection film and a 532nm anti-reflection film; the second beam splitter (2-11) is coated with a 45° 532nm high-reflection film and a 310nm anti-reflection film; the third beam splitter (3-3) is coated with a 45° 532nm high-reflection film, a 1064nm high-reflection film and a 355nm anti-reflection film.

5. The all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers according to claim 1, characterized in that: The frequency doubling crystal (1-4) is a type I phase-matched LBO crystal; the first parameter crystal (2-2) and the second parameter crystal (2-7) are type I phase-matched BBO crystals; the first sum frequency crystal (2-5) and the second sum frequency crystal (2-9) are type I phase-matched LBO crystals; and the third sum frequency crystal (3-1) and the fourth sum frequency crystal (3-2) are type I phase-matched LBO crystals.

6. The all-solid-state ultraviolet laser that simultaneously generates 310nm and 355nm high-energy lasers according to claim 1, characterized in that: The laser amplification module (1-2) includes an 808nm LD pump source and several amplifying crystals. The 1064nm single-frequency pulse seed laser is double-pass amplified by an end-face LD-pumped Nd:YVO4 crystal, double-pass amplified by a side-face LD-pumped Nd:YAG crystal, and finally power-amplified by a double-face LD-pumped Nd:YAG crystal to form a 1064nm fundamental frequency laser.

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