2-micron-band low-gain-medium high-peak-power and high-average-power laser device

Abstract

The utility model relates to the technical field of all-solid-state lasers, and discloses a 2-micron-waveband low-gain-medium high-peak-power and high-average-power laser device. The device comprises a 2-micron waveband low-gain medium module, a high-reflectivity mirror, a Q switch, a high-coupling-rate output mirror module, a low-coupling-rate output mirror module, a power supply and a controller, wherein the 2-micron wave band low-gain medium module, the high reflective mirror and the Q switch form a first group of 2-micron wave band low-gain medium laser oscillation amplification cavity and a second group of 2-micron wave band low-gain medium laser oscillation amplification cavity with the high-coupling-rate output mirror module and the low-coupling-rate output mirror module respectively. According to the utility model, the structural design of one-key switching of the first group and the second group of 2-micron wave band low-gain medium laser oscillation amplification cavities is adopted, so that one 2-micron wave band low-gain medium laser device not only can output high-peak-power laser, but also can output high-average-power laser, and the device is simple, high in reliability, few in devices and low in price; the method is widely applied to laser medical treatment, industrial manufacturing and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of all-solid-state lasers, in particular to a 2-micron band low-gain medium high peak power and high average power laser device. Background Art

[0002] The 2-micron laser band is a safe band for human eyes, especially this band covers the absorption peaks of many molecules, such as H2O, CO2, NO2, etc. It is widely used in laser medical treatment, industrial manufacturing, air pollution monitoring, etc. With the development of the 2-micron laser application market, 2-micron practical equipment with multiple functions, simple, compact and reliable, few components and low cost will be more favored by the market.

[0003] At present, the gain media commonly used to achieve 2-micron lasers mainly include single-doped holmium (Ho 3+ ) ionic crystal (Ho:YAG), single doped thulium (Tm 3+ ) ionic crystals (Tm:YLF, Tm:YAG, Tm:YAP), multi-doped thulium and holmium (Tm 3+ ,Ho 3+ ) ion crystals (Cr, Tm, Ho: YAG, Tm, Ho: YAG, Tm, Ho: YLF), etc. These crystals have a common disadvantage. Their stimulated emission cross-section values ​​are very small. For example, the stimulated emission cross-section value of Tm: YAG crystal is ~2×10 -21 / cm 2 , Nd:YAG crystal stimulated emission cross section value ~2.8×10 -19 / cm 2 , Yb:YAG crystal stimulated emission cross section ~2.1×10 -20 / cm 2 The stimulated emission cross section of Tm:YAG crystal is 1% of that of Nd:YAG crystal and 1 / 10 of that of Yb:YAG crystal. These crystals are collectively referred to as 2-micron low-gain media. In addition, lasers using these 2-micron low-gain media are three-level systems with heavy absorption and severe crystal thermal effects. Therefore, it is extremely difficult to output high peak power or high average power lasers using 2-micron low-gain media.

[0004] In recent years, scientific research institutions, universities, and enterprises at home and abroad have conducted in-depth research on 2-micron lasers. Technicians have used a compact and simple laser oscillator amplification cavity technology solution to obtain 100-watt high average power laser output, but the laser peak power is low, at the kilowatt (kW) level. The speed of industrial manufacturing 2-micron laser marking is slow, and laser medical 2-micron laser lithotripsy is not ideal. Furthermore, in order to obtain high-peak power laser output, technicians use a technical solution that combines laser oscillation amplification with a power amplification system, or a technical solution that uses multiple laser outputs and then beam combines them. However, this leads to a complex laser system, reduced reliability, and a large number of components with high costs, which hinders the widespread application of this technology. Utility Model Content

[0005] The utility model provides a 2-micron waveband low-gain medium high peak power and high average power laser device, which is used to solve or partially solve the deficiencies of the prior art.

[0006] The utility model provides a 2-micron band low-gain medium high peak power and high average power laser device, including a 2-micron band low-gain medium module, a high-reflection mirror, a Q switch, a high-coupling rate output mirror module, a low-coupling rate output mirror module, a power supply and a controller;

[0007] The 2-micron-band low-gain medium module, the high-reflection mirror, the Q switch, and the high-coupling rate output mirror module form a first group of 2-micron-band low-gain medium laser oscillation amplification cavities, and the low-coupling rate output mirror module form a second group of 2-micron-band low-gain medium laser oscillation amplification cavities; the first group and the second group of 2-micron-band low-gain medium laser oscillation amplification cavities are switched by the controller with one key, and 2-micron-band low-gain medium high peak power laser and high average power laser are output therefrom respectively;

[0008] The 2-micron low-gain medium module comprises: a 2-micron low-gain medium and a 780-795nm series semiconductor laser; wherein the 780-795nm series semiconductor laser emits pump light to excite the 2-micron low-gain medium; thereby the 2-micron low-gain medium module generates laser radiation; the 2-micron low-gain medium and the 780-795nm series semiconductor laser are both cooled by a water chiller (not shown in the figure);

[0009] The high-reflection mirror is plated with a 2-micron band 0° incident high-reflection film, with a reflectivity of not less than 99%, and is installed and fixed in the structural member, with the functions of preventing slippage and adjusting the optical path;

[0010] The Q switch is a 2-micron band acousto-optic Q switch / electro-optic Q switch, which is used to modulate the repetition frequency and pulse width of the 2-micron band laser;

[0011] The high coupling rate output mirror module comprises: a high coupling rate output mirror and a high coupling rate output mirror position moving and feedback device; the high coupling rate output mirror is fixedly mounted on the high coupling rate output mirror position moving and feedback device;

[0012] The low coupling rate output mirror module comprises: a low coupling rate output mirror and a low coupling rate output mirror position moving and feedback device; the low coupling rate output mirror is fixedly mounted on the low coupling rate output mirror position moving and feedback device;

[0013] The output coupling rate of the high coupling rate output mirror in the 2 micron band is T1, and the output coupling rate of the low coupling rate output mirror in the 2 micron band is T2, which needs to satisfy T1>T2; wherein 12%≤T1≤50%, 4%≤T2<12%; the power supply is connected to the 780-795nm series semiconductor laser to provide a DC power supply, and the DC voltage is greater than 20V;

[0014] The controller is used to operate the power supply and switch the first group of 2-micron-band low-gain medium laser oscillation amplification cavities or the second group of 2-micron-band low-gain medium laser oscillation amplification cavities in the laser device, that is, to automatically switch and optimize the position and orientation of the high-coupling rate output mirror module or the low-coupling rate output mirror module with one key;

[0015] Among them, when the controller switches to the first group of 2-micron band low-gain medium laser oscillation amplifying cavities: the high-coupling rate output mirror module automatically changes position and orientation through the high-coupling rate output mirror position movement and feedback device, optimizes the position of the high-coupling rate output mirror, and optimizes the sway in the water direction and the pitch in the vertical direction, so that the high-reflection mirror, Q switch, 2-micron band low-gain medium and high-coupling rate output mirror are in a coaxial arrangement relationship, meet the requirements of the laser resonant cavity, and obtain the first group of 2-micron band low-gain medium laser oscillation amplifying cavities; the high-coupling rate output mirror is used to reduce the surface peak power density of the device in the first group of 2-micron band low-gain medium laser oscillation amplifying cavities to ensure that the device is not damaged; the Q switch operates according to the initially set low repetition frequency range of 100 Hz to 1000 Hz and the pulse width nanosecond level; the laser radiation generated by the 2-micron band low-gain medium module is in the first group of 2 microns The 2-micron-band low-gain medium laser oscillates and amplifies in an oscillation amplification cavity. First, the power supply provides a direct current power supply so that the 2-micron-band low-gain medium module generates laser radiation. Then, the laser radiation is reflected and folded back by the high-reflection mirror during travel. The reflected and folded laser radiation is amplified by the 2-micron-band low-gain medium module. During travel, a portion of the amplified laser radiation is output by the high-coupling rate output mirror according to the output coupling rate T1, and the remaining portion is reflected and folded back. The reflected and folded laser radiation is amplified again by the 2-micron-band low-gain medium module, and then reflected and folded back by the high-reflection mirror. The reflected and folded laser radiation is amplified again by the 2-micron-band low-gain medium module. During travel, a portion of the amplified laser radiation is output by the high-coupling rate output mirror according to the output coupling rate T1, and the remaining portion is reflected and folded back. This cycle is repeated for multiple times to finally generate a 2-micron-band low-gain medium high-peak power laser, and the laser peak power is greater than 20,000 watts.

[0016] When the controller switches to the second group of 2-micron-band low-gain medium laser oscillation amplification cavities, the low-coupling rate output mirror module automatically changes position and orientation through the low-coupling rate output mirror position movement and feedback device, and optimizes the position of the low-coupling rate output mirror, so that the high-reflection mirror, the Q switch, the 2-micron-band low-gain medium and the low-coupling rate output mirror are in a coaxial arrangement relationship, meet the requirements of the laser resonant cavity, and obtain the second group of 2-micron-band low-gain medium laser oscillation amplification cavities; the low-coupling rate output mirror is used to maintain efficient power extraction in the second group of 2-micron-band low-gain medium laser oscillation amplification cavities; the Q switch operates at a high repetition frequency greater than 1kHz set initially; so that the laser radiation generated by the 2-micron-band low-gain medium module oscillates and amplifies in the second group of 2-micron-band low-gain medium laser oscillation amplification cavities, the low-coupling rate output mirror outputs a part according to the output coupling rate T2, and the remaining part is reflected and folded back, and multiple cycles are performed to finally generate a 2-micron-band low-gain medium high average power laser, and the laser average power is greater than 100 watts.

[0017] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the laser output from the first group and the second group of 2-micron band low-gain medium laser oscillation amplification cavities include single-arm coaxial output and double-arm non-coaxial output;

[0018] The controller switches with one key, and the high-coupling-rate output mirror module and the low-coupling-rate output mirror module automatically change their positions and orientations in the first and second groups of 2-micron-band low-gain medium laser oscillation amplification cavities, respectively, to generate 2-micron-band low-gain medium high-peak power laser and high-average power laser, respectively; when the 2-micron-band low-gain medium high-peak power laser and the high-average power laser are transmitted along the same arm and coaxially, it is called single-arm coaxial output; when the 2-micron-band low-gain medium high-peak power laser and the high-average power laser are transmitted along two arms and non-coaxially, it is called double-arm non-coaxial output.

[0019] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the first and second groups of 2-micron band low-gain medium laser oscillation amplifying cavities automatically change their positions and orientations by moving automatically on a horizontal plane and by rotating automatically on a vertical plane.

[0020] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the high-coupling rate output mirror and the low-coupling rate output mirror include two output coupling rates of T1 and T2 plated on the surface of one optical substrate and two output coupling rates of T1 and T2 plated on the surfaces of two optical substrates.

[0021] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the high-coupling rate output mirror position movement and feedback device and the low-coupling rate output mirror position movement and feedback device include a split structure and an integrated structure.

[0022] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the first and second groups of 2-micron band low-gain medium laser oscillation amplification cavities include 1 to 5 of the 2-micron band low-gain medium modules.

[0023] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the 2-micron band low-gain medium includes laser crystals of single-doped thulium ions, single-doped holmium ions and multi-doped thulium and holmium ions.

[0024] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the 2-micron band low-gain medium includes a rod structure, a block structure and a slab structure.

[0025] According to the 2 micron band low gain medium high peak power and high average power laser device provided by the utility model, the 780-795nm series semiconductor laser includes an array structure, a surface array structure and a fiber coupling structure.

[0026] According to the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model, the power supply includes a DC power supply and a pulse power supply, and the 780-795nm series semiconductor lasers include continuous wave semiconductor lasers, pulse semiconductor lasers and a mixture of continuous wave semiconductor lasers and pulse semiconductor lasers.

[0027] The utility model provides a 2-micron band low-gain medium high peak power and high average power laser device. The simplified structural design of the controller is used to switch the first and second groups of 2-micron band low-gain medium laser oscillation amplification cavities with one key, which solves the shortcomings of the existing 2-micron band low-gain medium laser technology and realizes that a 2-micron band low-gain medium laser device can output both high peak power laser (greater than 20,000 watts) and high average power laser (greater than 100 watts). It has multiple functions in one machine, is simple in device, has high reliability, has few components and is inexpensive, and has a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 This is one of the structural schematic diagrams of the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model;

[0030] Figure 2 This is the second structural schematic diagram of the 2-micron band low-gain medium high peak power and high average power laser device provided by the utility model.

[0031] Reference numerals:

[0032] 1. 2 micron band low gain dielectric module;

[0033] 11. Low-gain medium in the 2-micron band;

[0034] 12. 780~795nm series semiconductor lasers;

[0035] 2. High reflective mirror;

[0036] 3. Q switch;

[0037] 4. High coupling rate output mirror module;

[0038] 41. High coupling rate output mirror;

[0039] 42. High coupling rate output mirror position movement and feedback device;

[0040] 5. Low coupling rate output mirror module;

[0041] 51. Low coupling rate output mirror;

[0042] 52. Low coupling rate output mirror position movement and feedback device;

[0043] 53. 45° high reflector device;

[0044] 54. 45° high reflective mirror position movement and feedback device;

[0045] 6. Power supply;

[0046] 7. Controller. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be described clearly and completely in conjunction with the drawings in the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0048] In the description of the embodiment of the utility model, it should be noted that the first and second groups of 2-micron band low-gain dielectric laser oscillation amplifying cavities are interchangeable, including definitions, positional relationships, etc.;

[0049] In the description of the embodiments of the present utility model, it should be noted that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "middle", "inside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present utility model. The shapes of the various regions shown in the figures and the relative sizes and positional relationships therebetween are merely exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions with different shapes, sizes, and relative positions according to actual needs.

[0050] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense, for example, it can be a detachable connection or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood in specific circumstances.

[0051] Example 1

[0052] like Figure 1As shown, this embodiment provides a 2-micron band low-gain medium high peak power and high average power laser device. The device comprises a 2-micron band low-gain medium module 1, a high-reflection mirror 2, a Q switch 3, a high-coupling rate output mirror module 4, a low-coupling rate output mirror module 5, a power supply 6, and a controller 7; wherein the 2-micron band low-gain medium module 1, the high-reflection mirror 2, the Q switch 3, and the high-coupling rate output mirror module 4 form a first group of 2-micron band low-gain medium laser oscillation amplification cavity, which is a linear laser oscillation amplification cavity structure; the 2-micron band low-gain medium module 1, the high-reflection mirror 2, the Q switch 3, and the low-coupling rate output mirror module 5 form a second group of 2-micron band low-gain medium laser oscillation amplification cavity, which is a linear laser oscillation amplification cavity structure.

[0053] In this embodiment, a 2-micron band low-gain medium laser device switches the first and second groups of 2-micron band low-gain medium laser oscillation amplification cavities with one key through the controller 7, and outputs high peak power laser and high average power laser from the first and second groups of 2-micron band low-gain medium laser oscillation amplification cavities respectively. The two lasers with different functions are transmitted along the same arm and coaxially, which is called single-arm coaxial output.

[0054] In this embodiment, in order to make the 2-micron band low-gain medium laser device simple in structure and low in cost, the 2-micron band low-gain medium module 1, the high-reflection mirror 2, and the Q switch 3 are used as the common parts of the first group and the second group of 2-micron band low-gain medium laser oscillation amplification cavities. In the process of switching the first group and the second group of 2-micron band low-gain medium laser oscillation amplification cavities by one key on the interface of the controller 7, the position of the common part remains unchanged, and only the relative positions of the high-coupling rate output mirror module 4 and the low-coupling rate output mirror module 5 in the direction of the laser radiation travel path are changed. Both are in the horizontal plane along the direction perpendicular to the laser radiation travel. The high-coupling-rate output mirror position movement and feedback device 42 and the low-coupling-rate output mirror position movement and feedback device 52 are split structures; when one-key switch is made to the first group of 2-micron-band low-gain medium laser oscillation amplifying cavities, the high-coupling-rate output mirror module 4 will move into the laser radiation travel path in the horizontal plane, and the low-coupling-rate output mirror module 5 will move out in the horizontal plane to away from the laser radiation travel path; when one-key switch is made to the second group of 2-micron-band low-gain medium laser oscillation amplifying cavities, the relative position movement mode of the high-coupling-rate output mirror module 4 and the low-coupling-rate output mirror module 5 is exactly opposite.

[0055] Optionally, the 2-micron band low-gain medium module 1 is a 1×5-row three-dimensional side-pumped structure, in which the 2-micron band low-gain medium 11 is composed of a Tm:YLF / Tm:YAG crystal doped with thulium ions and is a rod-shaped structure with a diameter of To reduce reabsorption, 17mm long white YAG crystals are bonded to both ends of the crystal, and the total length of the crystal is 95mm; the crystal doping concentration is 3.5at.%Tm 3+ ; It also contains 780nm~795nm series semiconductor lasers 12, which are 785nm continuous wave semiconductor laser arrays. The array is a 1×5 horizontal array. The power of the pump light output by each array is greater than 250W, and the total output pump light power of the three-dimensional side pumping structure is greater than 750W; thereby, the pump light emitted by the 785nm continuous wave semiconductor laser array excites the Tm:YLF / Tm:YAG crystal to generate 2μm laser radiation; the Tm:YLF / Tm:YAG crystal and the 785nm continuous wave semiconductor laser array are both cooled by a water chiller (not described).

[0056] Optionally, the Q switch 3 is an acousto-optic Q switch in the 1.9 μm to 2.1 μm band, which is used to modulate the repetition frequency and pulse width of a 2-micron laser. When the controller 7 switches to the first group of 2-micron band low-gain medium laser oscillation amplification cavities with one key, the Q switch 3 operates according to the initial setting of the low repetition frequency of 600 Hz (which can be changed in the interface of the controller 7), and reducing the operating repetition frequency facilitates the energy storage in the first group of 2-micron band low-gain medium laser oscillation amplification cavities to increase the peak power of the nanosecond single-pulse laser; when the controller 7 switches to the second group of 2-micron band low-gain medium laser oscillation amplification cavities with one key, the Q switch operates according to the initial setting of the high repetition frequency of 10 kHz (which can be changed in the interface of the controller 7), and increasing the repetition frequency facilitates the reduction of the peak power density on the surface of the device in the second group of laser oscillation amplification cavities, and ensures that the devices in the second group of laser oscillation amplification cavities are not damaged when the average power output is high.

[0057] Optionally, the high-reflection mirror 2 has a 0° incident reflectivity greater than 99.5% in the 1.9μm to 2.1μm band. The high-reflection mirror has a diameter of 25mm and a thickness of 6mm. It is mounted and fixed on a tunable mirror frame and has the functions of preventing slipping and adjusting the optical path.

[0058] Optionally, the high coupling rate output mirror module 4 includes a high coupling rate output mirror 41 and a high coupling rate output mirror position moving and feedback device 42; the output coupling rate of the high coupling rate output mirror 41 in the 1.9μm to 2.1μm band is T1=40%, so the peak power density in the first group of 2-micron band low-gain medium laser oscillation amplifier cavity is only 4 times the value in the cavity, effectively reducing the peak power density on the surface of the device in the first group of 2-micron band low-gain medium laser oscillation amplifier cavity, ensuring that the device is not damaged; the high coupling rate output mirror 41 has a diameter of 25mm and a thickness of 6mm, and is fixed on the high coupling rate output mirror position moving and feedback device 42.

[0059] Optionally, the low coupling rate output mirror module 5 includes a low coupling rate output mirror 51 and a low coupling rate output mirror position moving and feedback device 52; the output coupling rate of the low coupling rate output mirror 51 in the 1.9μm to 2.1μm band is T1=10%, so the power density value inside the laser oscillation amplifier cavity is 19 times the value outside the cavity, effectively maintaining the efficient extraction of low gain medium laser power in the 2-micron band; the low coupling rate output mirror 51 has a diameter of 25mm and a thickness of 6mm, and is fixed on the low coupling rate output mirror position moving and feedback device 52.

[0060] Optionally, the high coupling rate output mirror 41 and the low coupling rate output mirror 51 are two quartz optical substrate surfaces respectively coated with films in the 1.9 μm to 2.1 μm band.

[0061] Optionally, the power supply 6 is a DC power supply, connected to the 780-795nm series semiconductor laser 12, and is used to provide a DC power supply with a DC voltage of 35V.

[0062] Optionally, the controller 7 is used to operate the power supply and switch the first and second groups of 2-micron band low-gain medium laser oscillation amplification cavities, that is, to automatically switch and optimize the positions of the high-coupling rate output mirror module and the low-coupling rate output mirror module with one button.

[0063] In the above embodiment, when the controller 7 switches to the first group of 2-micron-band low-gain medium laser oscillation amplifying cavities: the high-coupling rate output mirror module 4 automatically changes position and orientation through the high-coupling rate output mirror position movement and the feedback device 42, optimizes the position of the high-coupling rate output mirror 41, and optimizes the horizontal swing and the vertical pitch, so that the high-reflection mirror 2, the Q switch 3, the 2-micron-band low-gain medium 11 and the high-coupling rate output mirror 41 are in a coaxial arrangement relationship, meet the requirements of the laser resonant cavity, and obtain the first group of 2-micron-band low-gain medium laser oscillation amplifying cavities; because T1=40%, the high-coupling rate output mirror effectively reduces the surface peak power density of the device in the first group of 2-micron-band low-gain medium laser oscillation amplifying cavities, ensuring that the device is not damaged, and at the same time, the Q switch operates according to the initially set low repetition frequency of 600Hz, reducing the operating repetition frequency is convenient for the first group of 2-micron-band low-gain medium laser oscillation amplifying cavities to store energy and increase the peak power of the nanosecond single-pulse laser, and finally generate a 2-micron-band low-gain medium high peak power laser, and the laser peak power is greater than 20,000 watts.

[0064] In the above embodiment, when the controller 7 switches to the second group of 2-micron-band low-gain medium laser oscillation amplifying cavities: the low-coupling rate output mirror module 5 automatically changes its position and orientation through the low-coupling rate output mirror position movement and the feedback device 52, and optimizes the position of the low-coupling rate output mirror 51, so that the high-reflection mirror 2, the Q switch 3, the 2-micron-band low-gain medium and the low-coupling rate output mirror 51 are in a coaxial arrangement relationship, meeting the requirements of the laser resonant cavity, and obtaining the second group of 2-micron-band low-gain medium laser oscillation amplifying cavities; because T2=10%, the low-coupling rate output mirror effectively maintains the high-efficiency power extraction in the second group of 2-micron-band low-gain medium laser oscillation amplifying cavities, and the Q switch operates at the high repetition frequency of 10kHz initially set, and increasing the repetition frequency facilitates reducing the peak power density on the surface of the device in the second group of laser oscillation amplifying cavities, ensuring that the devices in the second group of laser oscillation amplifying cavities are not damaged when the high average power is output, and finally generating a 2-micron-band low-gain medium high average power laser, and the laser average power is greater than 100 watts.

[0065] Example 2

[0066] like Figure 2 As shown, this embodiment provides a 2-micron band low-gain medium high peak power and high average power laser device. The device comprises a 2-micron band low-gain medium module 1, a high-reflection mirror 2, a Q switch 3, a high-coupling rate output mirror module 4, a low-coupling rate output mirror module 5, a power supply 6, and a controller 7; wherein the 2-micron band low-gain medium module 1, the high-reflection mirror 2, the Q switch 3, and the high-coupling rate output mirror module 4 form a first group of 2-micron band low-gain medium laser oscillation amplification cavity, forming a linear laser oscillation amplification cavity structure; the 2-micron band low-gain medium module 1, the high-reflection mirror 2, the Q switch 3, and the low-coupling rate output mirror module 5 form a second group of 2-micron band low-gain medium laser oscillation amplification cavity, forming an L-type laser oscillation amplification cavity structure.

[0067] In this embodiment, a 2-micron band low-gain medium laser device switches the first and second groups of 2-micron band low-gain medium laser oscillation amplification cavities through the controller 7 with one key, and outputs high peak power laser and high average power laser from the first and second groups of 2-micron band low-gain medium laser oscillation amplification cavities respectively. The two lasers with different functions are transmitted along two arms non-coaxially, which is called dual-arm non-coaxial output.

[0068] In this embodiment, the same parts as those in Embodiment 1 include: a 2-micron band low-gain medium module 1, a high-reflection mirror 2, a Q switch 3, a power supply 6, and a controller 7, which will not be described here; the different parts include: a high-coupling rate output mirror module 4, and a low-coupling rate output mirror module 5, which will be described in detail.

[0069] Optionally, the high coupling rate output mirror module 4 includes a high coupling rate output mirror 41 with a diameter of 25 mm and a thickness of 6 mm. The output coupling rate in the 1.9 μm to 2.1 μm band is T1=40%. It is installed and fixed on a tunable mirror frame and has the functions of preventing slippage and adjusting the optical path.

[0070] Optionally, the low coupling rate output mirror module 5 includes a low coupling rate output mirror 51, a 45° high reflection mirror 53, and a 45° high reflection mirror position movement and feedback device 54; wherein the low coupling rate output mirror 51 has a diameter of 25 mm and a thickness of 6 mm, and an output coupling rate of T1=10% in the 1.9μm to 2.1μm band, and is mounted and fixed on a tunable mirror frame, and has the functions of preventing slippage and adjusting the optical path;

[0071] The 45° high reflective mirror 53 has a diameter of 30 mm and a thickness of 6 mm, and a 45° incident reflectivity greater than 99.5% in the 1.9 μm to 2.1 μm band. It is mounted and fixed on the 45° high reflective mirror position moving and feedback device 54 .

[0072] In the above embodiment, when the controller 7 switches to the first group of 2-micron-band low-gain medium laser oscillation amplification cavities: the position of the high-coupling rate output mirror module 4 remains unchanged, while the 45° high-reflection mirror position in the low-coupling rate output mirror module 5 moves and the feedback device 54 automatically changes position and orientation, so that the high-reflection mirror 2, the Q switch 3, the 2-micron-band low-gain medium 1 and the high-coupling rate output mirror 41 are in a coaxial arrangement relationship, meeting the requirements of the laser resonant cavity, forming the first group of 2-micron-band low-gain medium laser oscillation amplification cavities, and forming a linear laser oscillation amplification cavity; because T1=40%, the high-coupling rate output mirror effectively reduces the surface peak power density of the device in the first group of 2-micron-band low-gain medium laser oscillation amplification cavities, ensuring that the device is not damaged, and at the same time, the Q switch operates according to the initially set low repetition frequency of 600Hz, reducing the operating repetition frequency is convenient for the first group of 2-micron-band low-gain medium laser oscillation amplification cavities to store energy and increase the peak power of the nanosecond single-pulse laser, and finally generates a 2-micron-band low-gain medium high peak power laser, and the laser peak power is greater than 20,000 watts.

[0073] In the above embodiment, when the controller 7 switches to the second group of 2-micron-band low-gain medium laser oscillation amplifier cavities: the 45° high-reflection mirror position movement and feedback device 54 in the low-coupling rate output mirror module 5 automatically changes position and orientation, so that the 45° high-reflection mirror position movement and feedback device 54 brings the 45° high-reflection mirror 53 to move into the laser radiation path in a horizontal plane along a direction perpendicular to the laser radiation path, and optimizes the position of the 45° high-reflection mirror 53, so that the high-reflection mirror 2, the Q switch 3, the 2-micron-band low-gain medium 1 and the 45° high-reflection mirror, the high-coupling rate output mirror 51 are equivalent to being in a coaxial arrangement relationship, satisfying The laser resonant cavity requires that a second group of 2-micron-band low-gain dielectric laser oscillation amplifying cavities be formed to form an L-type laser oscillation amplifying cavity; because T2=10%, the low coupling rate output mirror effectively maintains efficient power extraction in the second group of 2-micron-band low-gain dielectric laser oscillation amplifying cavities, and at the same time, the Q switch operates at the initially set high repetition frequency of 10kHz. Increasing the repetition frequency facilitates reducing the peak power density on the surface of the device in the second group of laser oscillation amplifying cavities, ensuring that the devices in the second group of laser oscillation amplifying cavities are not damaged when high average power is output, and ultimately generating a 2-micron-band low-gain dielectric high average power laser with an average laser power greater than 100 watts.

[0074] In summary, through a 2-micron band low-gain medium high peak power and high average power laser device of Examples 1 and 2 of the utility model, a dual-function high peak power laser and a high average power laser are obtained. Compared with the existing 2-micron band low-gain medium laser technology, a laser device is used to switch the 2-micron band low-gain medium laser oscillation amplification cavity design through the controller 7 with one key, so as to realize one machine with multiple functions, which can output high peak power laser (greater than 20,000 watts) and high average power laser (greater than 100 watts). The device is simple and reliable, has few components and low cost, has a wider application direction, and can be practical.

[0075] In the specification of the present utility model, a lot of details are described. However, it is understood that the embodiments of the present utility model can be practiced without these specific details. In some examples, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this specification.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A 2-micron band low-gain medium high peak power and high average power laser device, It is characterized in that include: 2 micron band low-gain medium module (1), high reflection mirror (2), Q switch (3), high coupling rate output mirror module (4), low coupling rate output mirror module (5), power supply (6) and controller (7); The 2-micron-band low-gain medium module (1), the high-reflection mirror (2) and the Q switch (3), together with the high-coupling rate output mirror module (4), form a first group of 2-micron-band low-gain medium laser oscillation amplification cavities, and together with the low-coupling rate output mirror module (5), form a second group of 2-micron-band low-gain medium laser oscillation amplification cavities; the first group and the second group of 2-micron-band low-gain medium laser oscillation amplification cavities are switched by one key through the controller (7), and 2-micron-band low-gain medium high peak power laser and high average power laser are output therefrom respectively; The 2-micron-band low-gain medium module (1) comprises: a 2-micron-band low-gain medium (11) and a 780-795 nm series semiconductor laser (12); wherein the 780-795 nm series semiconductor laser (12) emits pump light to excite the 2-micron-band low-gain medium (11); and the 2-micron-band low-gain medium module (1) generates laser radiation; The high-reflection mirror (2) is coated with a 2-micron band 0° incident high-reflection film, and the reflectivity is not less than 99%; The Q switch (3) is a 2 micron band acousto-optic Q switch / electro-optic Q switch, used to modulate the repetition frequency and pulse width of a 2 micron laser; The high coupling rate output mirror module (4) comprises: a high coupling rate output mirror (41) and a high coupling rate output mirror position movement and feedback device (42); The low coupling rate output mirror module (5) comprises: a low coupling rate output mirror (51) and a low coupling rate output mirror position movement and feedback device (52); The output coupling rate of the high coupling rate output mirror (41) in the 2 micron band is T1, and the output coupling rate of the low coupling rate output mirror (51) in the 2 micron band is T2, satisfying T1>T2; wherein 12%≤T1≤50%, 4%≤T2<12%; The power supply (6) is connected to the 780-795nm series semiconductor laser (12) to provide a direct current power supply; The controller (7) is used to operate the power supply (6) to switch the first group or the second group of 2-micron-band low-gain medium laser oscillation amplification cavities of the laser device, that is, to automatically switch and optimize the position and orientation of the high-coupling rate output mirror module (4) or the low-coupling rate output mirror module (5) with one key; Wherein, when the controller (7) switches to the first group of 2 micron band low gain medium laser oscillation amplification cavities: the high coupling rate output mirror module (4) automatically switches to optimize the position and orientation through the high coupling rate output mirror position movement and feedback device (42), and automatically switches to optimize the position and orientation of the high coupling rate output mirror (41), so that the high reflection mirror (2), the Q switch (3), the 2 micron band low gain medium (11) and the high coupling rate output mirror (41) are in a coaxial arrangement relationship, and the first group of 2 micron band low gain medium laser oscillation amplification cavities is obtained. The high coupling rate output mirror (41) is used to reduce the peak power density of the device surface in the first group of 2 micron band low gain medium laser oscillation amplification cavities to ensure that the device is not damaged; the Q switch (3) operates according to the initially set low repetition frequency within the range of 100 Hz to 1000 Hz and the pulse width in nanoseconds; the laser radiation generated by the 2 micron band low gain medium module (1) oscillates and amplifies in the first group of 2 micron band low gain medium laser oscillation amplification cavities to generate 2 micron band low gain medium high peak power laser, and the laser peak power is greater than 20,000 watts; When the controller (7) switches to the second group of 2 micron band low gain medium laser oscillation amplification cavities, the low coupling rate output mirror module (5) automatically switches to optimize the position and orientation through the low coupling rate output mirror position movement and feedback device (52), and automatically switches to optimize the position and orientation of the low coupling rate output mirror (51), so that the high reflection mirror (2), the Q switch (3), the 2 micron band low gain medium (11) and the low coupling rate output mirror (51) are in a coaxial arrangement relationship, and the second group of 2 micron band low gain medium laser oscillation amplification cavities is obtained; the low coupling rate output mirror (51) is used to maintain high efficiency power extraction in the second group of 2 micron band low gain medium laser oscillation amplification cavities; the Q switch (3) operates at an initially set high repetition frequency greater than 1 kHz; the laser radiation generated by the 2 micron band low gain medium module (1) oscillates and amplifies in the second group of 2 micron band low gain medium laser oscillation amplification cavities, generating 2 micron band low gain medium high average power laser, and the laser average power is greater than 100 watts.

2. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The lasers output from the first and second groups of 2-micron-band low-gain medium laser oscillation amplifier cavities include single-arm coaxial output and double-arm non-coaxial output; The controller (7) is switched with one key, and the high coupling rate output mirror module (4) and the low coupling rate output mirror module (5) automatically change their positions and orientations in the first group and the second group of 2-micron-band low-gain medium laser oscillation amplification cavities, respectively, to generate 2-micron-band low-gain medium high peak power laser and high average power laser, respectively; when the 2-micron-band low-gain medium high peak power laser and the high average power laser are transmitted along the same arm and coaxially, it is called single-arm coaxial output; when the 2-micron-band low-gain medium high peak power laser and the high average power laser are transmitted along two arms and non-coaxially, it is called double-arm non-coaxial output.

3. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The automatic position and orientation changing modes of the first and second groups of 2-micron band low-gain medium laser oscillation amplifying cavities include automatic changing modes of moving on a horizontal plane and automatic changing modes of rotating on a vertical plane.

4. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The high coupling rate output mirror (41) and the low coupling rate output mirror (51) include two output coupling rates, T1 and T2, plated on the surface of one optical substrate and two output coupling rates, T1 and T2, plated on the surfaces of two optical substrates.

5. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The high coupling rate output mirror position movement and feedback device (42) and the low coupling rate output mirror position movement and feedback device (52) include a split structure and an integrated structure.

6. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The first group and the second group of 2-micron-band low-gain medium laser oscillation amplification cavities include 1 to 5 of the 2-micron-band low-gain medium modules (1).

7. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The 2-micron band low-gain medium includes laser crystals of single-doped thulium ions, single-doped holmium ions and multi-doped thulium-holmium ions.

8. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The 2-micron band low-gain medium includes a rod structure, a block structure and a slab structure.

9. The 2-micron band low-gain medium high peak power and high average power laser device according to claim 1, It is characterized in that The 780-795 nm series semiconductor laser (12) comprises an array, a plane array and an optical fiber coupling structure.

10. The 2-micron band low-gain medium high peak power and high average power laser device according to any one of claims 1 to 9, It is characterized in that The power source (6) includes a direct current power source and a pulse power source; the 780-795 nm series semiconductor laser (12) includes a continuous wave semiconductor laser, a pulse semiconductor laser and a mixture of a continuous wave semiconductor laser and a pulse semiconductor laser.

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