High-energy space-time coupling laser device and application method

Abstract

The invention relates to the technical field of medical laser ablation, and discloses a high-energy space-time coupling laser device and an application method, and the device comprises a pulse delay control unit which is used for generating a plurality of time sequence electric signals; the laser generation unit comprises a plurality of laser subunits which are connected in parallel, each laser subunit receives a time sequence electric signal which is in one-to-one correspondence, and the laser subunits are used for generating corresponding preset pulse laser according to the time sequence electric signal and the time sequence; and the laser synthesis unit is used for receiving the preset pulse laser sent by the laser subunit, performing light beam coupling on the multiple beams of preset pulse laser in space and time and then outputting the multiple beams of preset pulse laser. By means of the high-energy space-time coupling laser device, high-energy laser can be generated, the requirement for arbitrary configuration of laser output energy can be met through parallel connection of the multiple laser subunits, the problem that pulse energy improvement of a high-energy ultraviolet nanosecond laser is limited is solved, and medical application of laser ablation is met.

Description

Technical Field

[0001] The present invention relates to the technical field of medical laser ablation, and in particular to a high-energy space-time coupled laser device and an application method thereof. Background Art

[0002] In the field of medical laser ablation, lasers are used to emit lasers and transmit them to the target location through catheters for ablation. The ablation effect often depends on the energy of the laser. Because there is a loss of laser energy from the laser to the catheter, the laser needs to output a larger energy to meet the ablation needs. However, increasing the output energy of existing lasers can easily lead to pulse width problems and damage the catheter. Therefore, it is difficult to meet the energy and safety requirements using conventional lasers.

[0003] In order to increase the output energy of the laser, the existing technology generally uses a set of laser resonant cavities to increase the laser output pulse energy by increasing the size of the laser crystal in the resonant cavity. However, under this method, the size of the laser crystal cannot be increased infinitely, and the existing technology has reached the bottleneck of pulse energy. Therefore, when the size of the laser crystal is not too large, it can only generate less than or equal to 90mJ of energy, and the improvement of laser pulse energy has certain limitations.

[0004] In order to meet different ablation requirements, pulse width adjustment or broadening is required. The existing technology generally uses a single-stage or multi-stage beam splitting and combining structure outside the laser to achieve this. The specific process includes: firstly splitting the pulse spatially, then introducing a distance of several meters or even ten meters between different beams to produce a time delay of the pulse, and finally combining the delayed pulses to obtain a laser pulse with a broadened pulse width. However, this method requires the use of a huge spatial optical path and a large number of reflectors and lenses. The complex structure not only increases the size of the laser but is also not conducive to the engineering production of the product.

[0005] In addition, during laser ablation, 355nm lasers are often used for laser emission because of the greater advantages of 355nm wavelength lasers. In order to achieve pulse broadening of 355 lasers, the conventional 355nm high-energy high-frequency lasers (pulse width 5-10ns, maximum frequency 100Hz@80mJ) currently on the market are used for medical laser ablation. The pulse width is too narrow, resulting in excessively high pulse peak power when used at high energy density, making it difficult to ensure catheter reliability. Related technologies increase the pulse width by adding spatial delays outside the laser to obtain a pulse train to reduce peak power and ensure catheter reliability. However, this method has limited delays between pulses, and the spatial length of the delay structure increases exponentially with the delay. Summary of the invention

[0006] In view of this, the present invention provides a high-energy space-time coupled laser device and application method, which can generate high-energy laser. By connecting multiple laser sub-units in parallel, the demand for arbitrary configuration of laser output energy can be realized, which can meet the medical application of laser ablation to solve the technical problems raised in the above background.

[0007] In a first aspect, the present invention provides a high energy spatiotemporal coupled laser device, the device comprising:

[0008] A pulse delay control unit is used to generate a plurality of sequential electrical signals, and the sequential electrical signals are used to trigger the generation of pulsed lasers; the pulse delay control unit is also used to control the time intervals between the plurality of sequential electrical signals and the frequency and pulse width of each sequential electrical signal according to preset pulsed laser output requirements;

[0009] The laser generating unit comprises a plurality of laser sub-units connected in parallel, each laser sub-unit receiving a one-to-one corresponding timing electrical signal, and the laser sub-unit is used to generate a corresponding preset pulse laser in a timing sequence according to the timing electrical signal;

[0010] The laser synthesis unit is used to receive the preset pulse laser sent by the laser sub-unit, and output multiple beams of preset pulse laser after beam coupling in space and time.

[0011] In this embodiment, the pulse delay control unit sends a plurality of different timing electrical signals to the laser generating unit, the laser generating unit processes the plurality of timing electrical signals, and outputs a plurality of pulsed lasers to the laser synthesis unit, the laser synthesis unit synthesizes the plurality of pulsed lasers, and delivers them to the coupling module and the catheter for laser ablation application. Among them, the laser generating unit is composed of a plurality of laser sub-units connected in parallel, so that high-energy laser can be generated, and the requirement of pulse width widening can be met. The embodiment of the present invention can solve the problem of limited pulse energy enhancement of high-energy ultraviolet nanosecond lasers and the difficulty of flexible adjustment of pulse width or interval, and meets the medical application of laser ablation.

[0012] In an optional embodiment, the laser subunit comprises:

[0013] A laser resonant cavity, comprising a total reflection mirror, a laser gain medium and an output mirror, wherein the laser resonant cavity is used to generate laser light under the excitation of a preset pump source;

[0014] The supporting circuit includes a nonlinear crystal and a Q-switched optical switch. The nonlinear crystal includes a frequency doubling crystal and a sum frequency crystal. The total reflection mirror, the laser gain medium, the Q-switched optical switch, the frequency doubling crystal, the output mirror and the sum frequency crystal are arranged in sequence. The Q-switched optical switch is used to adjust the laser so that it meets the preset pulse laser output requirements of the laser subunit.

[0015] In an optional embodiment, the laser subunit further includes:

[0016] A detection and adjustment unit, the detection and adjustment unit is used to detect the laser energy passing through the nonlinear crystal and also to adjust the temperature of the nonlinear crystal;

[0017] The high energy spatiotemporal coupled laser device also includes:

[0018] The control unit is used to collect the laser energy detected by the detection and adjustment unit, and is also used to control the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the laser energy.

[0019] The detection and adjustment unit provided in the laser subunit in this embodiment can realize energy detection and temperature adjustment of the nonlinear crystal, so that the temperature of the nonlinear crystal is always maintained at the optimal operating temperature, thereby ensuring that the laser conversion efficiency is maximized and will not be limited by the size or temperature of the nonlinear crystal, etc., thereby effectively ensuring the conversion efficiency of the nonlinear crystal.

[0020] In this embodiment, high energy output and pulse width extension of the laser are achieved.

[0021] In an optional implementation, the detection and adjustment unit includes:

[0022] A first beam splitter, disposed between the output mirror and the sum frequency crystal, for partially reflecting the laser light emitted from the output mirror;

[0023] A first energy detector, used for detecting the laser energy after being reflected by the first beam splitter, and sending the laser energy to the control unit;

[0024] The first temperature controller is used to adjust the temperature of the frequency doubling crystal according to the control signal of the control unit.

[0025] In an optional implementation, the detection and adjustment unit includes:

[0026] A second beam splitter is arranged in the light-emitting direction of the sum frequency crystal and is used to partially reflect the laser light emitted from the sum frequency crystal;

[0027] The second energy detector is used to detect the laser energy reflected by the second beam splitter and send the laser energy to the control unit.

[0028] The second temperature controller is used to adjust the temperature of the sum frequency crystal according to the control signal of the control unit.

[0029] In this embodiment, a spectroscope, an energy detector and a temperature controller are arranged in the laser subunit, which can realize energy detection and temperature regulation of the nonlinear crystal, so that the temperature of the nonlinear crystal is always maintained at the optimal operating temperature, thereby ensuring that the laser conversion efficiency is maximized and will not be limited by the size or temperature of the nonlinear crystal, thereby effectively ensuring the conversion efficiency of the nonlinear crystal.

[0030] In an optional embodiment, the device further comprises:

[0031] A third beam splitter is arranged in the laser output direction of the laser synthesis unit and is used to reflect the laser emitted from the laser synthesis unit;

[0032] The third energy detector is used to detect the total laser energy after being reflected by the third beam splitter and send the total laser energy to the control unit.

[0033] In this embodiment, the user can be assisted to understand the high-energy laser parameters of the synthesized laser, ensuring that the high-energy laser output by the laser synthesis unit meets the preset requirements, so that the user can adjust the required laser output requirements in real time.

[0034] In an optional embodiment, the device further comprises:

[0035] An indicator light, used to emit an indicator light, the indicator light is used to indicate the output direction of the laser output by the laser synthesis unit;

[0036] A reflector, arranged in the light emitting direction of the indicator light, for reflecting the indicator light;

[0037] The dichroic mirror is arranged in the output direction of the laser output by the laser synthesis unit and in the light output direction of the reflected light of the reflector. The dichroic mirror is used to reflect the indication light so that the reflected indication light coincides with the laser output by the laser synthesis unit.

[0038] In this embodiment, the direction of laser emission can be indicated, thereby improving the safety specification of laser use.

[0039] In an optional embodiment, the laser gain medium generates a 1064nm laser under the stimulation of a preset pump source, which is transmitted to a total reflection mirror to generate total reflection; after the laser gain medium amplifies the totally reflected laser, it periodically generates laser pulses through a Q-switched optical switch under the control of a timing electrical signal, so that the laser generation delays entering a frequency doubling crystal; part of the 1064nm laser generates a doubled frequency 532nm laser, and the remaining 1064nm laser and the generated 532nm laser partially enter the sum frequency crystal through the output mirror, and are partially reflected back to the frequency doubling crystal and the Q-switched optical switch, and are used for the next laser adjustment cycle; the 1064nm laser and the 532nm laser entering the sum frequency crystal are partially sum-frequency-generated into a 355nm laser, thereby obtaining a 355nm laser that meets the output requirements.

[0040] In a second aspect, the present invention provides an application method of a high-energy space-time coupled laser device, which is applicable to the high-energy space-time coupled laser device of any of the above embodiments, and the application method comprises:

[0041] The pulse delay control unit generates a plurality of sequential electrical signals and sends the plurality of sequential electrical signals to the laser generating unit, wherein the sequential electrical signals are used to control the operation of the laser generating unit; wherein the pulse delay control unit also controls the time interval between the plurality of sequential electrical signals and the frequency and pulse width of each sequential electrical signal according to the preset laser output requirements;

[0042] The laser generating unit generates corresponding pulsed lasers in time sequence according to the received time sequence electrical signals, and inputs the generated multiple pulsed lasers into the laser synthesis unit; wherein the laser subunit comprises: a laser resonant cavity, a matching circuit and a detection and adjustment unit, wherein the laser resonant cavity comprises a total reflection mirror, a laser gain medium and an output mirror; the matching circuit comprises a nonlinear crystal and a Q-switched optical switch, and the nonlinear crystal comprises a frequency doubling crystal and a sum frequency crystal;

[0043] The laser synthesis unit couples the input multiple pulse laser beams in space and time and then outputs them; the laser generation unit includes multiple parallel laser sub-units;

[0044] The control unit controls the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the collected laser energy detected by the detection and adjustment unit.

[0045] In an optional implementation, controlling the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the collected laser energy detected by the detection and adjustment unit includes:

[0046] collecting the current first laser energy passing through the nonlinear crystal;

[0047] Determine the temperature adjustment step size;

[0048] According to the adjustment step length, the temperature of the nonlinear crystal is increased to obtain the second laser energy passing through the nonlinear crystal;

[0049] determining whether the second laser energy is increased compared to the first laser energy;

[0050] When the second laser energy increases compared to the first laser energy, continue to increase the temperature of the nonlinear crystal according to the adjustment step until the second laser energy decreases compared to the first laser energy;

[0051] When the second laser energy is less than the first laser energy, the adjustment step length is adjusted to a preset multiple of the adjustment step length, and the temperature of the nonlinear crystal is increased by the preset multiple of the adjustment step length to obtain a third laser energy passing through the nonlinear crystal;

[0052] determining whether the third laser energy is increased compared to the first laser energy;

[0053] When the third laser energy increases compared to the first laser energy, the temperature of the nonlinear crystal continues to increase according to the adjustment step of the preset multiple until the third laser energy decreases compared to the first laser energy.

[0054] In this embodiment, nonlinear crystal energy detection and temperature regulation can be achieved, so that the temperature of the nonlinear crystal is always maintained at the optimal operating temperature, thereby ensuring that the laser conversion efficiency is maximized and will not be limited by the size or temperature of the nonlinear crystal. This effectively ensures the conversion efficiency of the nonlinear crystal and meets the medical application of laser ablation. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0056] Figure 1 is a schematic structural diagram of a high-energy spatiotemporal coupled laser device according to an embodiment of the present invention;

[0057] Figure 2 is a schematic structural diagram of a laser synthesis unit according to an embodiment of the present invention;

[0058] Figure 3 is a schematic structural diagram of another laser synthesis unit according to an embodiment of the present invention;

[0059] Figure 4 is a schematic structural diagram of a laser subunit according to an embodiment of the present invention;

[0060] Figure 5 is a schematic diagram of the structure of the laser synthesis unit after output according to an embodiment of the present invention;

[0061] Figure 6 is a flow chart of an application method of a high energy spatiotemporal coupled laser device according to an embodiment of the present invention;

[0062] Figure 7 is a schematic diagram of a flow chart of nonlinear crystal temperature regulation according to an embodiment of the present invention;

[0063] Explanation of the accompanying drawings: 1-pulse delay control unit, 2-laser generating unit, 21-laser subunit, 211-total reflection mirror, 212-laser gain medium, 213-output mirror, 214-Q-switched optical switch, 215-frequency doubling crystal, 216-sum frequency crystal, 217-first spectroscope, 218-first energy detector, 219-second spectroscope, 220-second energy detector, 221-first temperature controller, 222-second temperature controller, 223-third spectroscope, 224-third energy detector, 225-indicator light, 226-reflector, 227-dichroic mirror, 228-filter, 3-laser synthesis unit, 4-control unit. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0065] In addition to the limited laser energy and laser pulse width, the laser resonant cavity used in the related art will have a temperature change of the laser crystal in the resonant cavity due to the influence of the working environment temperature, which will greatly affect the stability of the high-energy laser output energy. In addition, the temperature change of the laser crystal will also cause the loss of laser output energy, greatly reducing the conversion efficiency of the laser. In the case of outputting high-energy lasers, in order to minimize the loss of output laser energy, the conversion efficiency of the entire high-energy space-time coupled laser device needs to be maximized. The conversion efficiency of the high-energy space-time coupled laser device generally depends on the conversion efficiency of the nonlinear crystal (frequency doubling crystal 215 and sum frequency crystal 216).

[0066] However, the temperature of nonlinear crystals is easily affected by many factors, and it is impossible to keep the temperature of nonlinear crystals at the optimal working temperature all the time. For example: 1. After the laser has worked for a long time, the optical path misalignment inside will cause the optimal working temperature of the crystal to change slightly (generally within ±2 degrees); 2. After the crystal has worked for a long time, the performance has aged, resulting in a slight change in the optimal temperature; 3. After a long time, the deviation of the crystal support structure itself causes a slight change in the optimal temperature; 4. Factors such as environmental humidity have an impact on the optimal working temperature.

[0067] In view of this, a high energy spatiotemporal coupling laser device is provided in this embodiment, such as Figure 1 As shown, the device includes: a pulse delay control unit 1, a laser generating unit 2, and a laser synthesis unit 3, and the details are as follows.

[0068] The pulse delay control unit 1 is used to generate multiple sequential electrical signals, and the sequential electrical signals are used to trigger the generation of pulsed lasers; the pulse delay control unit 1 is also used to control the time intervals between the multiple sequential electrical signals and the frequency and pulse width of each sequential electrical signal according to the preset pulse laser output requirements. Specifically, the pulse delay adjustment unit can accurately control the pulse output time of the laser resonant cavity in each laser subunit 21, and obtain double pulses or multiple pulses with any time interval to achieve the purpose of pulse width / pulse interval adjustment to meet the medical application of laser ablation. Among them, the pulse delay control unit 1 can accurately control the pulse output time of each laser resonant cavity in the laser generating unit 2, and can achieve any configuration requirements for pulse width broadening, solve the problem of the difficulty in flexibly adjusting the pulse width or interval, and the problem of the difficulty in ensuring the reliability and easy damage of the catheter under high energy, and meet the medical application of laser ablation.

[0069] Specifically, refer to Figure 1 As shown, the pulse delay control unit 1 generates a plurality of sequential electrical signals, which are respectively denoted as S1, S2, ..., S n , where n is the number of sequential electrical signals; its function is to control the multiple laser resonant cavities in the laser generating unit 2 to sequentially generate laser pulses according to the sequential signals. In this embodiment, the preset pulse laser output requirements include the output laser energy and the laser pulse width, which are only used as examples and are not limited to this. They can be adaptively adjusted according to actual needs. Specifically, the relative delay between the multiple sequential electrical signals of the pulse delay control unit 1, the frequency and pulse width of each sequential electrical signal can be adjusted according to the set laser pulse width, so as to change the delay and pulse width of the output laser.

[0070] The laser generating unit 2 comprises a plurality of laser subunits 21 connected in parallel. Each laser subunit 21 receives a one-to-one corresponding timing electrical signal. The laser subunit 21 is used to generate a corresponding preset pulse laser in a timing sequence according to the timing electrical signal.

[0071] Still refer to Figure 1 Specifically, the laser generating unit 2 comprises a plurality of parallel laser subunits 21, each of which can generate a pulsed laser beam, and the plurality of parallel laser subunits 21 generate a plurality of pulsed laser beams, which are respectively denoted as L1, L2, ..., L n , where n is the number of pulsed lasers, and all laser beams output by the laser generating unit 2 are input into the laser synthesis unit 3. It should be noted that the number of pulsed lasers, the number of parallel laser subunits 21, and the number of sequential electrical signals are all the same.

[0072] The laser synthesis unit 3 is used to receive the preset pulse laser sent by the laser sub-unit 21, and output multiple beams of preset pulse laser after beam coupling in space and time.

[0073] In this embodiment, the laser beam synthesized by the laser synthesis unit 3 is presented as a train of pulses in the time domain, and the number of pulses in the pulse train is equal to the parallel number n of the laser subunits 21 in the laser generation unit 2. The time interval t0 between pulses in the pulse train can be independently adjusted to generate different delay amounts and pulse widths. Based on actual application requirements, the pulse train is called BurstTrain.

[0074] In this embodiment, the beam coupling method may include: using a laser polarization beam coupling method or a laser wavelength difference beam coupling method. Specifically, by designing a variety of beam coupling methods, it is possible to match the corresponding beam synthesis method for different types of lasers, which helps to improve the efficiency of beam synthesis and improve the energy output efficiency of the high-energy spatiotemporal coupling laser device of the embodiment of the present invention to a certain extent.

[0075] Reference Figure 2 As shown, a method of using laser polarization beam coupling in the laser synthesis unit 3 is provided. This embodiment takes two laser beams as an example to illustrate the process of coupling the two laser beams in space and time. Figure 2 It can be seen that L1 and L2 are two 355nm linearly polarized laser beams, and the two laser beams then pass through a 1 / 2 wave plate respectively. The wave plate is used to change the polarization direction of the linearly polarized light. After L1 is reflected by the laser reflector M1, it is incident on the polarization beam splitter or thin film polarizer M together with L2. Since the polarization directions of L1 and L2 are different, the effects of L1 reflection and L2 transmission are obtained on the polarization beam splitter or thin film polarizer M, so as to achieve strict spatial coupling of the two laser beams. In addition, the time interval t0 between the coupled laser pulses can be controlled by adjusting the time delay between the trigger signals S1 and S2 in the pulse delay control unit 1. The method of coupling laser polarization beams has the advantage of simple structure and is suitable for linearly polarized pulses.

[0076] Figure 3A method of utilizing laser wavelength difference beam coupling in the laser synthesis unit 3 is provided. This embodiment uses three laser beams as an example to illustrate the coupling process in space and time. It should be noted that this method of utilizing slight differences in laser wavelengths for beam coupling is mainly aimed at output laser types with different central wavelengths of each laser. For example, the central wavelengths of the three laser beams L1, L2 and L3 differ by 0.5 nm, which is only used as an example and is not limited to this. Based on the principle that the grating has different diffraction angles for different wavelengths, the spatial overlap of different laser wavelengths can be achieved by using a transmission grating in reverse. In addition, the adjustment of the time interval between pulses after the three laser beams L1, L2 and L3 overlap is consistent with the method described in the embodiment of the method utilizing laser polarization beam coupling, and will not be repeated here.

[0077] It should be noted that the beam coupling method in the laser synthesis unit 3 in this embodiment is not specifically limited. In addition to the aforementioned method of using laser polarization beam coupling and the method of using laser wavelength difference beam coupling, it can also be adaptively adjusted according to actual application requirements.

[0078] In this embodiment, the pulse delay control unit 1 sends a plurality of different timing electrical signals to the laser generating unit 2. The laser generating unit processes the plurality of timing electrical signals and outputs a plurality of pulsed lasers to the laser synthesis unit 3. The laser synthesis unit synthesizes the plurality of pulsed lasers and delivers them to the coupling module and the catheter for laser ablation application. Among them, the laser generating unit 2 is composed of a plurality of laser sub-units 21 connected in parallel, so that high-energy lasers can be generated and the requirement of pulse width broadening can be met. The embodiment of the present invention can solve the problem of limited pulse energy enhancement of high-energy ultraviolet nanosecond lasers and the difficulty of flexible adjustment of pulse width or interval, and meets the medical application of laser ablation.

[0079] In some optional embodiments, the laser subunit 21 includes:

[0080] A laser resonant cavity, comprising a total reflection mirror 211, a laser gain medium 212 and an output mirror 213, the laser resonant cavity is used to generate laser under the excitation of a preset pump source;

[0081] The supporting circuit includes a nonlinear crystal and a Q-switched optical switch 214. The nonlinear crystal includes a frequency doubling crystal 215 and a sum frequency crystal 216. Among them, the total reflection mirror 211, the laser gain medium 212, the Q-switched optical switch 214, the frequency doubling crystal 215, the output mirror 213 and the sum frequency crystal 216 are arranged in sequence. The Q-switched optical switch 214 is used to adjust the laser so that it meets the preset pulse laser output requirements of the laser subunit 21.

[0082] In this embodiment, each laser subunit 21 has the same configuration, including a laser resonant cavity and a supporting circuit. Figure 4, the laser resonant cavity includes: a total reflection mirror 211, an output mirror 213 and a laser gain medium 212, which are used to generate laser under the excitation of a preset pump source; the supporting circuit is used to adjust the laser and make it meet the preset laser output requirements, and the devices of the supporting circuit include: a Q-switched optical switch 214, a frequency doubling crystal 215, and a sum frequency crystal 216; wherein, the Q-switched optical switch 214 is used to periodically control the loss of the laser resonant cavity to generate a laser that meets the preset laser output requirements, the frequency doubling crystal 215 is used to output the frequency doubling laser, and the sum frequency crystal 216 is used to output the sum frequency laser. It should be noted that the preset pump source of this embodiment is not specifically limited and is determined according to actual application requirements; the switch signal trigger time of the Q-switched optical switch 214 is determined by the timing electrical signal S1 generated by the pulse delay control unit 1, and the timing electrical signal S1 is adjusted based on the control of the pulse delay control unit 1, and the corresponding control signal is provided through the signal line.

[0083] The embodiment of the present invention is based on a laser subunit 21 including a laser resonant cavity and supporting circuits. By connecting multiple laser subunits 21 in parallel and synthesizing the pulses output by the multiple laser subunits 21, it is easy to obtain more than 150mJ, or even theoretically unlimited high-energy nanosecond ultraviolet lasers, solving the current problem of limited pulse energy enhancement of 355nm ultraviolet nanosecond lasers. In addition, the multi-beam combination performed by multiple laser resonants in the embodiment of the present invention can disperse the heat generated in the laser resonant cavity due to quantum loss and frequency doubling conversion process to multiple laser resonants, which is helpful for heat dissipation of the entire device; at the same time, the embodiment of the present invention is also helpful when operating at high energy for a long time, that is, when more heat is generated at high energy, the efficiency of laser generation is still maintained at a high level, avoiding the problem of slow energy decay due to long-term use of heat treatment.

[0084] In this embodiment, the laser gain medium 212 can be a neodymium-doped yttrium aluminum garnet Nd:YAG crystal or a neodymium-doped yttrium vanadate Nd:YVO4 crystal, which is only used as an example and can be adaptively adjusted according to actual application requirements. Specifically, the Nd:YAG crystal or Nd:YVO4 crystal used can achieve good harmonic conversion efficiency based on the high optical quality of such crystals, is suitable for high average power solid-state lasers, and helps to improve the efficiency of laser generation.

[0085] In this embodiment, the total reflection mirror 211 is a concave reflection mirror 226, the surface of which is coated with a 1064nm high reflection dielectric film, and the reflectivity is close to 100%; the output mirror 213 is a concave reflection mirror 226, the surface of which is coated with a 1064nm high reflection film and a 532nm high transmission film, the reflectivity of 1064nm is between 70% and 97%, and the transmittance of 532nm is higher than 98%. Specifically, the laser resonant cavity can provide optical positive feedback, and the laser generation efficiency of the laser resonant cavity is improved to a certain extent by configuring the total reflection mirror 211 and the output mirror 213.

[0086] In this embodiment, the frequency doubling crystal 215 can be a lithium triborate LBO crystal or a barium metaborate BBO crystal, which is only used as an example and can be adaptively adjusted according to actual application requirements. Specifically, LBO crystal or BBO crystal is used. This type of crystal has excellent optical quality, very high laser damage threshold and ultraviolet penetration ability, and also has a good frequency doubling effect. For the output of 355nm strong pulsed ultraviolet light with high energy and high peak power, it can meet its stringent requirements for crystal damage threshold, which helps to improve the efficiency of laser generation.

[0087] In some optional embodiments, the laser subunit 21 further includes:

[0088] The detection and adjustment unit is used to detect the laser energy passing through the nonlinear crystal and to adjust the temperature of the nonlinear crystal.

[0089] The high energy spatiotemporal coupled laser device also includes:

[0090] The control unit 4 is used to collect the laser energy detected by the detection and adjustment unit, and is also used to control the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the laser energy, so that the temperature clock of the nonlinear crystal is maintained at an optimal temperature.

[0091] Reference Figure 4 As shown, the detection and adjustment unit may include a spectroscope, an energy detector and a temperature controller, wherein the energy detector may be used to detect the laser energy after being split by the spectroscope, and then the detected laser energy is sent to the control unit 4, and the control unit 4 sends a control signal to the temperature controller according to the feedback laser energy, and then the temperature controller increases or decreases the temperature of the nonlinear crystal to keep the temperature clock of the nonlinear crystal at the optimal temperature. Energy detection and temperature adjustment of the nonlinear crystal can ensure that the conversion efficiency of the laser is maximized.

[0092] In this embodiment, the detection and adjustment unit provided in the laser subunit 21 can realize energy detection and temperature adjustment of the nonlinear crystal, so that the temperature of the nonlinear crystal is always maintained at the optimal operating temperature, thereby ensuring that the laser conversion efficiency reaches the maximum and will not be limited by the size or temperature of the nonlinear crystal, etc., effectively ensuring the conversion efficiency of the nonlinear crystal.

[0093] In some optional implementations, the detection and adjustment unit may include:

[0094] The first beam splitter 217 is disposed in the light emitting direction of the output mirror 213 , that is, between the output mirror 213 and the sum frequency crystal 216 , and is used for partially reflecting the laser light emitted from the output mirror 213 .

[0095] The first energy detector 218 is used to detect the laser energy reflected by the first beam splitter 217 and send the laser energy to the control unit 4 .

[0096] The first temperature controller 221 is used to adjust the temperature of the frequency doubling crystal 215 according to the control signal of the control unit 4 .

[0097] In some optional embodiments, the detection and adjustment unit includes:

[0098] The second beam splitter 219 is disposed in the light emitting direction of the sum frequency crystal 216 , and is used for partially reflecting the laser light emitted from the sum frequency crystal 216 .

[0099] The second energy detector 220 is used to detect the laser energy reflected by the second beam splitter 219 and send the laser energy to the control unit 4 .

[0100] The second temperature controller 222 is used to adjust the temperature of the sum frequency crystal 216 according to the control signal of the control unit 4 .

[0101] Specifically, two spectroscopes and an energy detector (power / energy meter detection) are added in each laser subunit 21 , and a TEC temperature controller is added to each nonlinear crystal in each laser subunit 21 .

[0102] The first beam splitter 217 can be arranged between the output mirror 213 and the sum frequency crystal 216, and is used to reflect the 532nm laser to the first energy detector 218. The first energy detector 218 sends the detected laser power / energy E1 to the control unit 4. The control unit 4 compares the detected E1 with a preset laser threshold. If it is lower than the threshold, the control unit 4 controls the first temperature controller 221 to adjust the temperature of the frequency doubling crystal 215 with a step size of T1.

[0103] The second beam splitter 219 can be arranged after the frequency doubling crystal 216 to reflect the 355nm laser to the second energy detector 220. The second energy detector 220 sends the detected laser power / energy E2 to the control unit 4. The control unit 4 compares the detected E2 with a preset laser threshold. If it is lower than the threshold, the control unit 4 controls the second temperature controller 222 to adjust the temperature of the frequency doubling crystal 215 with a step size of T2.

[0104] Here, the frequency doubling crystal 215 and the sum frequency crystal 216 can detect and adjust the temperature at the same time, or the sum frequency crystal 216 can detect and adjust the temperature after the frequency doubling crystal 215 completes the detection and adjustment, which is not limited here.

[0105] In this embodiment, a spectroscope, an energy detector and a temperature controller are provided in the laser subunit 21, which can realize energy detection and temperature regulation of the nonlinear crystal, so that the temperature of the nonlinear crystal is always maintained at the optimal operating temperature, thereby ensuring that the laser conversion efficiency is maximized and will not be limited by the size or temperature of the nonlinear crystal, etc., effectively ensuring the conversion efficiency of the nonlinear crystal.

[0106] Reference Figure 5 As shown, in some optional embodiments, the device further includes:

[0107] The third beam splitter 223 is disposed in the laser output direction of the laser synthesis unit 3 and is used to reflect the laser emitted from the laser synthesis unit 3 .

[0108] The third energy detector 224 is used to detect the total laser energy after being reflected by the third beam splitter 223 and send the total laser energy to the control unit 4. The total laser energy is used to determine whether the laser output by the laser synthesis unit 3 is a high-energy laser.

[0109] Reference Figure 5 As shown, after the laser synthesis unit 3 outputs high-energy laser, in order to obtain real-time power / energy and determine whether it is a high-energy output, a spectroscope and an energy detector (power meter / energy meter) can be set on the optical path after the beam is combined. The spectroscope is used to reflect 1% of the synthesized laser into the energy detector, and the energy detector feeds back the detected power / energy to the user. At this time, the user can know whether a high-energy laser is obtained. This can help the user understand the high-energy laser parameters of the synthesized laser, and ensure that the high-energy laser output by the laser synthesis unit 3 meets the preset requirements, so that the user can adjust the required laser output requirements in real time.

[0110] Reference Figure 5 As shown, in some optional embodiments, the device further includes:

[0111] The indicator light 225 is used to emit an indication light, and the indication light is used to indicate the output direction of the laser output by the laser synthesis unit 3.

[0112] The reflector 226 is disposed in the light emitting direction of the indicator light 225 and is used to reflect the indicator light.

[0113] The dichroic mirror 227 is arranged in the output direction of the laser output by the laser synthesis unit 3 and in the light output direction of the reflected light of the reflector 226. The dichroic mirror 227 is used to reflect the indication light so that the reflected indication light coincides with the laser output by the laser synthesis unit 3.

[0114] Since 355nm laser is invisible light, the output 355nm laser cannot be observed by the naked eye, and thus it is easy to fail to meet safety regulations when used. Therefore, before applying the 355nm laser, it is possible to first detect whether there is light output, and then use the 355nm laser in a safe and standardized manner. In this embodiment, an indicator light 225, a reflector 226, and a dichroic mirror 227 can be added to the output light path. Among them, the indicator light can be played by LD (for example, 750nm), the reflector 226 realizes the reflection of the LD indicator light, and the dichroic mirror 227 is used to reflect the indicator light and transmit ultraviolet light, so that the 355nm laser and the indicator light overlap to indicate the direction of laser emission, thereby improving the safety regulations for laser use.

[0115] In some optional embodiments, the laser gain medium 212 generates a 1064nm laser under the stimulation of a preset pump source, which is transmitted to the total reflection mirror 211 to generate total reflection; after the laser gain medium 212 amplifies the totally reflected laser, it periodically generates laser pulses through the Q-switched optical switch 214 under the control of a timing electrical signal, so that the laser generation delays entering the frequency doubling crystal 215; part of the 1064nm laser generates a doubled frequency 532nm laser, and the remaining 1064nm laser and the generated 532nm laser partially enter the sum frequency crystal 216 through the output mirror 213, and part of them are reflected back to the frequency doubling crystal 215 and the Q-switched optical switch 214, and are used for the next laser adjustment cycle; the 1064nm laser and the 532nm laser entering the sum frequency crystal 216 are partially sum-frequency-converted into a 355nm laser, thereby obtaining a 355nm laser that meets the output requirements.

[0116] When laser ablation is performed, 355nm lasers are often used for laser emission because of the greater advantages of 355nm wavelength lasers. The above is the output process of one of the laser subunits 21 generating a 355nm laser that meets the requirements when the high-energy spatiotemporal coupling laser device provided in this embodiment is used to output high-energy lasers. Further, the 355nm laser generated by the laser subunit 21 is transmitted to the laser synthesis unit 3, and the laser synthesis unit 3 spatially combines two or more 355nm high-energy lasers, thereby achieving high-energy output and pulse width broadening of the laser.

[0117] In addition, a filter 228 may be provided after the sum frequency crystal 216, and the 1064nm laser and the 532nm laser entering the sum frequency crystal 216 are partially sum-frequency-converted into 355nm laser and are subjected to transmission or reflection processing by the filter 228. The processing includes the 1064nm laser and the 532nm laser being blocked and reflected by the filter 228, and the 355nm laser being transmitted through the filter 228, thereby obtaining a 355nm laser that meets the output requirements.

[0118] In this embodiment, an application method of a high-energy spatiotemporal coupling laser device is also provided, which can be performed by the high-energy spatiotemporal coupling laser device provided in any of the above embodiments. Figure 6 is a flow chart of an application method of a high energy spatiotemporal coupled laser device according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0119] Step S101, the pulse delay control unit 1 generates a plurality of timing electrical signals, and sends the plurality of timing electrical signals to the laser generating unit 2, wherein the timing electrical signals are used to control the operation of the laser generating unit 2; wherein the pulse delay control unit 1 also controls the time interval between the plurality of timing electrical signals and the frequency and pulse width of each timing electrical signal according to the preset laser output requirements.

[0120] Step S102, the laser generating unit 2 generates corresponding pulse lasers in sequence according to the received timing electrical signal, and inputs the generated multiple pulse lasers into the laser synthesis unit 3; wherein, referring to Figure 1 As shown, the laser generating unit 2 comprises a plurality of laser subunits 21 connected in parallel. Figure 4 As shown, the laser subunit 21 includes: a laser resonant cavity, supporting circuits and a detection and adjustment unit, wherein the laser resonant cavity includes a total reflection mirror 211, a laser gain medium 212 and an output mirror 213; the supporting circuit includes a nonlinear crystal and a Q-switched optical switch 214, and the nonlinear crystal includes a frequency doubling crystal 215 and a sum frequency crystal 216.

[0121] In step S103, the laser synthesis unit 3 performs beam coupling on the input multiple pulse laser beams in space and time and then outputs the beams.

[0122] Step S104 : the control unit 4 controls the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the collected laser energy detected by the detection and adjustment unit.

[0123] The application method of the high-energy spatiotemporal coupling laser device of the embodiment of the present invention can spatially combine two or more 355nm high-energy lasers through the spatiotemporal coupling of multiple laser resonant cavities and multiple beams, solving the problem of limited pulse energy enhancement of the current 355nm ultraviolet nanosecond laser, and can easily obtain pulsed lasers of more than 150mJ, and even obtain theoretically unlimited high-energy nanosecond ultraviolet lasers. The pulse delay control unit 1 accurately controls the pulse output time of each laser resonant cavity, and can obtain double pulses or multiple pulses with any time interval to achieve the purpose of adjusting the pulse width or pulse interval, solving the problem of adjusting the pulse width of high-energy ultraviolet nanosecond lasers and meeting the demand for pulse width broadening.

[0124] In this embodiment, nonlinear crystal energy detection and temperature regulation can also be achieved, so that the temperature of the nonlinear crystal is always maintained at the optimal operating temperature, thereby ensuring that the laser conversion efficiency is maximized and will not be limited by the size or temperature of the nonlinear crystal. This effectively ensures the conversion efficiency of the nonlinear crystal and meets the medical application of laser ablation.

[0125] In some optional implementations, controlling the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the collected laser energy detected by the detection and adjustment unit includes:

[0126] collecting the current first laser energy passing through the nonlinear crystal;

[0127] Determine the temperature adjustment step size;

[0128] According to the adjustment step length, the temperature of the nonlinear crystal is increased to obtain the second laser energy passing through the nonlinear crystal;

[0129] determining whether the second laser energy is increased compared to the first laser energy;

[0130] When the second laser energy increases compared to the first laser energy, the temperature of the nonlinear crystal continues to increase according to the adjustment step until the second laser energy decreases compared to the first laser energy.

[0131] When the second laser energy is less than the first laser energy, the adjustment step length is adjusted to a preset multiple of the adjustment step length, and the temperature of the nonlinear crystal is increased by the preset multiple of the adjustment step length to obtain a third laser energy passing through the nonlinear crystal;

[0132] determining whether the third laser energy is increased compared to the first laser energy;

[0133] When the third laser energy increases compared to the first laser energy, the temperature of the nonlinear crystal continues to increase according to the adjustment step of the preset multiple until the third laser energy decreases compared to the first laser energy.

[0134] In this embodiment, the detection of the temperature-controlled frequency-doubling crystal 215 is taken as an example for explanation. When the current first laser energy a1 detected by the first energy detector 218 (energy / power meter detection) is compared with the preset threshold value X, the energy becomes smaller, and the temperature of the frequency-doubling crystal 215 is adjusted by adjusting the step size t1. The t1 can be set to 0.5°C, 1°C, 2°C, etc., and X can be 300mJ, which is not limited here.

[0135] Specifically, refer to Figure 7 As shown, the following process can be adopted to control the detection and adjustment unit to adjust the temperature of the nonlinear crystal: when the temperature of the frequency doubling crystal 215 increases by t1, the first energy detector 218 detects that the second laser energy a2 of the frequency doubling crystal 215 increases compared to the first laser energy a1, that is, when the energy increases for the first time during heating, it means that the energy has not reached the highest peak value, and the temperature of the frequency doubling crystal 215 continues to be increased with an adjustment step of t1, that is, heating again, until it is detected that the second laser energy a2 decreases compared to the first laser energy a1, it means that the energy has reached the peak value, and the temperature adjustment is stopped. At this time, it is considered that the temperature of the frequency doubling crystal 215 has reached the optimal operating temperature.

[0136] When the temperature of the frequency doubling crystal 215 increases by t1, and the first energy detector 218 detects that the second laser energy a2 of the frequency doubling crystal 215 is reduced compared to the first laser energy a1, that is, when the first heating energy is reduced, it means that the temperature adjustment is wrong, and the temperature of the frequency doubling crystal 215 needs to be reduced by an adjustment step of a preset multiple, for example: 2×t1. If the third laser energy a3 detected after the reduction increases, that is, when the first cooling energy increases, the temperature of the frequency doubling crystal 215 is still reduced by the adjustment step t1 until it is detected that the third laser energy a3 is reduced compared to the first laser energy a1, that is, the cooling energy is reduced again, it means that the energy has reached the peak value, and the temperature adjustment is stopped. At this time, it is considered that the temperature of the frequency doubling crystal 215 has reached the optimal operating temperature.

[0137] In addition, the following process can be used to control the detection and adjustment unit to adjust the temperature of the nonlinear crystal: when the temperature of the frequency doubling crystal 215 decreases by t1, the first energy detector 218 detects that the second laser energy a2 of the frequency doubling crystal 215 increases compared to the first laser energy a1, that is, when the energy increases during the first cooling, it means that the energy has not reached the highest peak value, and the temperature of the frequency doubling crystal 215 continues to be increased with an adjustment step of t1, that is, the temperature is lowered again until it is detected that the second laser energy a2 decreases compared to the first laser energy a1, which means that the energy has reached the peak value, and the temperature adjustment is stopped. At this time, it is considered that the temperature of the frequency doubling crystal 215 has reached the optimal operating temperature.

[0138] When the temperature of the frequency doubling crystal 215 decreases by t1, the first energy detector 218 detects that the second laser energy a2 of the frequency doubling crystal 215 is reduced compared to the first laser energy a1, that is, the energy is reduced for the first cooling, which indicates that the temperature adjustment is wrong, and the temperature of the frequency doubling crystal 215 needs to be increased by an adjustment step of a preset multiple, for example: 2×t1. If the third laser energy a3 detected after the increase increases, that is, the energy is increased for the first heating, the temperature of the frequency doubling crystal 215 is still increased by the adjustment step t1 until it is detected that the third laser energy a3 is reduced compared to the first laser energy a1, that is, the heating energy is reduced again, which indicates that the energy has reached the peak value, and the temperature adjustment is stopped. At this time, it is considered that the temperature of the frequency doubling crystal 215 has reached the optimal operating temperature.

[0139] Similarly, the adjustment method of the sum frequency crystal 216 is the same as that of the frequency doubling crystal 215, which will not be repeated here; for the specific description of the high energy space-time coupled laser device, please refer to the high energy space-time coupled laser device part, which will not be repeated here.

[0140] In this embodiment, the process of generating pulsed laser is as follows: the laser gain medium 212 generates 1064nm laser under the stimulation of a preset pump source, and transmits it to the total reflection mirror 211 to generate total reflection; after the laser gain medium 212 amplifies the totally reflected laser, it periodically generates laser pulses through the Q-switched optical switch 214 under the control of the timing electrical signal, so that the laser generation delay enters the frequency doubling crystal 215; part of the 1064nm laser generates a doubled frequency 532nm laser, and the remaining 1064nm laser and the generated 532nm laser are Part of it enters the sum frequency crystal 216 through the output mirror 213, and part of it is reflected back to the frequency doubling crystal 215 and the Q-switched optical switch 214, and is used for the next laser adjustment cycle; the 1064nm laser and the 532nm laser entering the sum frequency crystal 216 are partially summed into 355nm laser and are transmitted or reflected by the filter 228. The processing includes the 1064nm laser and the 532nm laser being blocked and reflected by the filter 228, and the 355nm laser being transmitted through the filter 228, thereby obtaining a 355nm laser that meets the output requirements.

[0141] In this embodiment, the laser energy output by the laser synthesis unit 3 is n×A×B%mJ, where n is the number of laser subunits 21 in parallel, A is the laser energy output by each laser subunit 21, and B% is the synthesis efficiency of the laser synthesis unit 3; the laser pulse width output by the laser synthesis unit 3 is (m-1)×T+m×t ns, where T is the time interval of each timing electrical signal, m is the number of pulses, and t is the width of each pulse. It should be noted that, taking a triangular pulse as an example, the width of each pulse is the half-maximum full width, so the pulse train width is calculated based on the half-maximum full width of the entire pulse train.

[0142] The embodiment of the present invention provides a specific numerical basis for the output of the laser synthesis unit 3 according to the formula of the energy and pulse width of the laser output by the laser synthesis unit 3, and can realize any configuration requirements of high-energy laser and pulse width broadening, meeting the medical application of laser ablation.

[0143] In a specific embodiment, taking the three laser subunits 21 outputting three pulses respectively as an example, the laser energy output by each laser subunit 21 is 90mJ, and the synthesis efficiency of the laser synthesis unit 3 is 85%, then the three parallel laser subunits 21 output 3×A×B%=3×90×85%=229.5mJ of laser energy, which greatly improves the laser energy. When the width t of each pulse is 20ns, and the time interval T of the three timing electrical signals is the same and is 10ns, then at this time, the three parallel laser subunits 21 output pulsed lasers and after the beam coupling processing of the laser synthesis unit 3, the pulse width of the output laser is (3-1)×10+20=40ns, realizing the configuration requirements of outputting high-energy laser and widening the pulse width. It should be noted that all the numerical values ​​involved in the above process are used as examples, and are not limited to this, and can be adaptively adjusted according to actual application requirements.

[0144] In summary, the application method of the high-energy spatiotemporal coupling laser device provided in the embodiment of the present invention realizes high-energy output and pulse width widening of the laser. The embodiment of the present invention solves the problem that when applied to medical laser ablation, the laser ablation catheter end is insufficient in energy due to excessive loss of the additional widened optical path, resulting in a limited application range of the ablation object. In the embodiment of the present invention, the pulse time interval between each laser resonant cavity is adjustable, and the same laser single pulse energy and peak power effect as in the case of pulse width widening can be obtained. The output laser does not need to adjust the pulse width, and only needs to be coupled after spot shaping. Compared with the widened optical path, the energy loss of the laser output energy in the widened optical path is greatly reduced, which can not only improve the stability and reliability of the whole system, but also reduce the difficulty of making the ablation catheter coupling end, and reduce the manufacturing process cost of the catheter coupling end. In addition, in this embodiment, the nonlinear crystal energy detection and temperature adjustment can be realized, so that the temperature of the nonlinear crystal is always kept at the optimal working temperature, thereby ensuring that the laser conversion efficiency reaches the maximum, and will not be limited by the size or temperature of the nonlinear crystal, etc., effectively ensuring the conversion efficiency of the nonlinear crystal, and meeting the medical application of laser ablation.

[0145] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A high energy spatiotemporal coupled laser device, characterized in that: The device comprises: A pulse delay control unit (1) is used to generate a plurality of sequential electrical signals, wherein the sequential electrical signals are used to trigger the generation of pulsed lasers; the pulse delay control unit (1) is also used to control the time interval between the plurality of sequential electrical signals and the frequency and pulse width of each sequential electrical signal according to preset pulsed laser output requirements; A laser generating unit (2) comprising a plurality of laser subunits (21) connected in parallel, each of the laser subunits (21) receiving a one-to-one corresponding timing electrical signal, and the laser subunit (21) being used to generate a corresponding preset pulse laser in a timing sequence according to the timing electrical signal; The laser synthesis unit (3) is used to receive the preset pulse laser sent by the laser subunit (21), and output multiple beams of the preset pulse laser after beam coupling in space and time.

2. The device according to claim 1, characterized in that The laser subunit (21) comprises: A laser resonant cavity, comprising a total reflection mirror (211), a laser gain medium (212) and an output mirror (213), wherein the laser resonant cavity is used to generate laser light under the excitation of a preset pump source; The supporting circuit comprises a nonlinear crystal and a Q-switched optical switch (214), wherein the nonlinear crystal comprises a frequency doubling crystal (215) and a sum frequency crystal (216); wherein the total reflection mirror (211), the laser gain medium (212), the Q-switched optical switch (214), the frequency doubling crystal (215), the output mirror (213) and the sum frequency crystal (216) are arranged in sequence, and the Q-switched optical switch (214) is used to adjust the laser so that it meets the preset pulse laser output requirements of the laser subunit (21).

3. The device according to claim 2, characterized in that The laser subunit (21) further comprises: A detection and adjustment unit, the detection and adjustment unit is used to detect the laser energy passing through the nonlinear crystal and to adjust the temperature of the nonlinear crystal; The device also includes: A control unit (4) is used to collect the laser energy detected by the detection and adjustment unit, and is also used to control the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the laser energy.

4. The device according to claim 3, characterized in that The detection and adjustment unit comprises: A first beam splitter (217), arranged between the output mirror (213) and the sum frequency crystal (216), and used for partially reflecting the laser light emitted from the output mirror (213); A first energy detector (218) for detecting laser energy reflected by the first beam splitter (217) and sending the laser energy to the control unit (4); A first temperature controller (221) is used to adjust the temperature of the frequency doubling crystal (215) according to a control signal from the control unit (4).

5. The device according to claim 3 or 4, characterized in that The detection and adjustment unit comprises: A second beam splitter (219) is arranged in the light emitting direction of the sum frequency crystal (216) and is used to partially reflect the laser light emitted from the sum frequency crystal (216); A second energy detector (220) is used to detect the laser energy reflected by the second beam splitter (219), and send the laser energy to the control unit (4); A second temperature controller (222) is used to adjust the temperature of the sum frequency crystal (216) according to a control signal from the control unit (4).

6. The device according to claim 1, characterized in that The device also includes: A third beam splitter (223), arranged in the laser output direction of the laser synthesis unit (3), and used for reflecting the laser light emitted from the laser synthesis unit (3); The third energy detector (224) is used to detect the total laser energy after being reflected by the third beam splitter (223), and send the total laser energy to the control unit (4).

7. The device according to claim 2, characterized in that The device also includes: An indicator light (225), used for emitting an indication light, wherein the indication light is used for indicating the output direction of the laser light output by the laser synthesis unit (3); A reflector (226), arranged in the light emitting direction of the indicator light (225), and used for reflecting the indicator light; A dichroic mirror (227) is arranged in the output direction of the laser light output by the laser synthesis unit (3) and in the light output direction of the reflected light by the reflector (226), and the dichroic mirror (227) is used to reflect the indication light so that the indication light after reflection coincides with the laser light output by the laser synthesis unit (3).

8. The device according to claim 2, characterized in that The laser gain medium (212) generates 1064nm laser light under the stimulation of a preset pump source, and transmits the laser light to the total reflection mirror (211) to generate total reflection; after the laser gain medium (212) amplifies the totally reflected laser light, it periodically generates laser pulses through the Q-switching optical switch (214) under the control of a timing electrical signal, so that the laser light is delayed in entering the frequency doubling crystal (215); part of the 1064nm laser light generates a doubled frequency 532nm laser light, and the remaining 1064nm laser light and the generated 532nm laser light partially enter the sum frequency crystal (216) through the output mirror (213), and part of the laser light is reflected back to the frequency doubling crystal (215) and the Q-switching optical switch (214), and is used for the next laser adjustment cycle; the 1064nm laser light and the 532nm laser light entering the sum frequency crystal (216) are partially sum-frequency-generated into a 355nm laser light, so as to obtain a 355nm laser light that meets the output requirements.

9. An application method of a high-energy spatiotemporal coupled laser device, characterized in that: Applied to the high energy spatiotemporal coupled laser device according to any one of claims 1 to 8, the application method comprising: The pulse delay control unit (1) generates a plurality of sequential electrical signals and sends the plurality of sequential electrical signals to the laser generating unit (2), wherein the sequential electrical signals are used to control the operation of the laser generating unit (2); wherein the pulse delay control unit (1) further controls the time interval between the plurality of sequential electrical signals and the frequency and pulse width of each sequential electrical signal according to preset laser output requirements; The laser generating unit (2) generates corresponding pulsed lasers in time sequence according to the received time sequence electrical signals, and inputs the generated multiple pulsed lasers into the laser synthesis unit (3); wherein the laser generating unit (2) comprises a plurality of laser subunits (21) connected in parallel, and the laser subunits (21) comprise: a laser resonant cavity, a matching circuit, and a detection and adjustment unit, wherein the laser resonant cavity comprises a total reflection mirror (211), a laser gain medium (212), and an output mirror (213); the matching circuit comprises a nonlinear crystal and a Q-switched optical switch (214), and the nonlinear crystal comprises a frequency doubling crystal (215) and a sum frequency crystal (216); The laser synthesis unit (3) couples the input multiple pulse laser beams in space and time and then outputs them; The control unit (4) controls the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the collected laser energy detected by the detection and adjustment unit.

10. The method according to claim 9, characterized in that The step of controlling the detection and adjustment unit to adjust the temperature of the nonlinear crystal according to the collected laser energy detected by the detection and adjustment unit comprises: collecting a current first laser energy passing through the nonlinear crystal; Determine the temperature adjustment step size; According to the adjustment step, increasing the temperature of the nonlinear crystal to obtain a second laser energy passing through the nonlinear crystal; determining whether the second laser energy is increased compared to the first laser energy; When the second laser energy increases compared to the first laser energy, continue to increase the temperature of the nonlinear crystal according to the adjustment step until the second laser energy decreases compared to the first laser energy; When the second laser energy is less than the first laser energy, the adjustment step is adjusted to a preset multiple of the adjustment step, and the temperature of the nonlinear crystal is increased by the preset multiple of the adjustment step to obtain a third laser energy passing through the nonlinear crystal; determining whether the third laser energy is increased compared to the first laser energy; When the third laser energy increases compared to the first laser energy, the temperature of the nonlinear crystal continues to be increased according to the adjustment step of the preset multiple until the third laser energy decreases compared to the first laser energy.

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