Elliptic cylinder laser device and laser amplifier

Abstract

The invention discloses an elliptic cylinder laser device and a laser amplifier, the laser device comprises a pumping source, an elliptic cylinder gain medium, a reflection module and a resonant cavity, the pumping source is used for providing pumping light for a large surface of the elliptic cylinder gain medium; the reflection module is used for reflecting the emergent pump light absorbed by the elliptic cylinder gain medium back to the elliptic cylinder gain medium, so that the elliptic cylinder gain medium performs multi-pass absorption on the pump light to generate laser; the resonant cavity comprises a reflecting mirror located on one side of the first end face of the elliptic cylinder gain medium and an output mirror located on one side of the second end face of the elliptic cylinder gain medium, the resonant cavity is used for reflecting and amplifying the laser, and the output mirror is used for outputting the amplified laser. Pump light is absorbed through the elliptic cylinder gain medium, and when the sectional areas of the elliptic cylinder gain medium in the light passing direction are the same, compared with a rod-shaped gain medium, the incident aperture and the heat dissipation area of the pump light are increased; compared with a batten gain medium, waste of light beams and waste of lens calibers are avoided, and the power and the utilization rate of laser are improved.

Description

Technical Field

[0001] The present invention relates to the field of solid lasers. More specifically, it relates to an elliptical cylinder laser device and a laser amplifier. Background Art

[0002] With the continuous progress of laser technology, the applications of high-power lasers in the fields of industry, scientific research, military, etc. have gradually increased. However, during the actual operation of high-power lasers, serious thermal effect problems are faced, mainly manifested as too large temperature gradient and damage power limitation of laser materials. These problems directly affect the stability and performance of the lasers. In order to effectively reduce the thermal effect and improve the heat dissipation efficiency, it is usually necessary to increase the aperture of the laser to improve the heat dissipation efficiency and reduce local heat accumulation, thereby improving the thermal management of the laser.

[0003] In order to optimize the performance of the laser, the slab laser medium, as a new design solution, has gradually attracted attention. Its spot shape is square, and compared with the traditional circular spot, it effectively reduces the temperature gradient and improves the heat dissipation ability. However, when the slab laser scheme is integrated with the existing optical system, obvious problems occur in the case of adapting to the telescope emission system. The telescope emission end uses an optical lens group based on a circular aperture, which is designed according to the principles of Gaussian beam transmission and focusing, aiming to achieve the minimum aberration and the highest light energy utilization rate. When the square spot of the slab laser is coupled into such an emission system, a mode mismatch phenomenon occurs, resulting in the inability of the edge region of the lens to effectively participate in the beam transmission, greatly reducing the actual utilization rate of the emission lens aperture, and even causing high-order diffraction loss, resulting in laser power attenuation and affecting the efficiency of the entire emission system. Summary of the Invention

[0004] The present invention provides an elliptical cylinder laser device and a laser amplifier to solve at least one of the problems existing in the prior art.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The first aspect of the present invention provides an elliptical cylinder laser device, which includes a pump source, an elliptical cylinder gain medium, a reflection module, and a resonator. Among them,

[0007] The pump source is used to provide pump light to the large surface of the elliptical cylinder gain medium;

[0008] The reflection module is used to reflect the pump light emitted after being absorbed by the elliptical cylinder gain medium back to the elliptical cylinder gain medium, so that the elliptical cylinder gain medium generates laser after multi-pass absorption of the pump light;

[0009] The resonant cavity includes a reflector on one side of the first end face of the elliptical cylinder gain medium and an output mirror on one side of the second end face of the elliptical cylinder gain medium. The resonant cavity is used to reflect and amplify the laser, and the output mirror is used to output the amplified laser.

[0010] Optionally, the pump source includes at least one set of pump bar groups arranged at intervals along the axial direction of the elliptical cylinder gain medium on the large surface of the elliptical cylinder gain medium. One pump bar group includes a plurality of pump bars arranged at intervals along the circumferential direction of the elliptical cylinder gain medium. The pump bars are used to provide pump light to the large surface of the elliptical cylinder gain medium.

[0011] Optionally, the reflection module includes a plurality of reflection sub-module groups. One reflection sub-module group includes a reflection sub-module located between adjacent pump bars in one pump bar group.

[0012] Optionally, the laser device further includes a cooling sleeve covering the large surface of the elliptical cylinder gain medium.

[0013] Optionally, the laser device further includes a pump light shaping module. The pump light shaping module is arranged between the pump source and the elliptical cylinder gain medium and is used to shape the pump light into elliptical pump light.

[0014] In a second aspect of the present invention, an elliptical cylinder laser device is provided. The laser device includes a pump source, an elliptical cylinder gain medium, and a resonant cavity.

[0015] The pump source is used to provide pump light to the first end face of the elliptical cylinder gain medium;

[0016] The elliptical cylinder gain medium is used to exponentially absorb the pump light to generate laser;

[0017] The resonant cavity includes a reflector on one side of the first end face of the elliptical cylinder gain medium and an output mirror on one side of the second end face of the elliptical cylinder gain medium. The resonant cavity is used to reflect and amplify the laser, and the output mirror is used to output the amplified laser.

[0018] Optionally, the laser device further includes a first plane mirror. The first plane mirror is arranged between the reflector and the elliptical cylinder gain medium and is used to reflect the pump light and transmit the laser.

[0019] Optionally, the laser device further includes a pump light shaping module. The pump light shaping module is arranged between the pump source and the first plane mirror and is used to shape the pump light into elliptical pump light.

[0020] The third aspect of the present invention provides a laser amplifier, which includes a seed source, an elliptical cylinder gain medium, a pump source, and a reflection module. Among them,

[0021] The pump source is used to provide pump light to the large surface of the elliptical cylinder gain medium;

[0022] The seed source is used to provide seed laser to the first end face of the elliptical cylinder gain medium;

[0023] The reflection module is used to reflect the pump light emitted after being absorbed by the elliptical cylinder gain medium back to the elliptical cylinder gain medium, so that the elliptical cylinder gain medium performs multi-pass absorption on the pump light and amplifies the energy of the seed laser incident through the first end face of the elliptical cylinder gain medium;

[0024] The second end face of the elliptical cylinder gain medium is used to output the amplified seed laser.

[0025] The fourth aspect of the present invention provides a laser amplifier, which is characterized in that the laser amplifier includes a pump source, a seed source, a second plane mirror, and an elliptical cylinder gain medium. Among them,

[0026] The pump source is used to provide pump light to the first end face of the elliptical cylinder gain medium;

[0027] The seed source is used to provide seed laser to the first end face of the elliptical cylinder gain medium;

[0028] The second plane mirror is used to reflect the pump light and transmit the seed laser, or reflect the seed laser and transmit the pump light;

[0029] The elliptical cylinder gain medium performs exponential absorption on the pump light and amplifies the energy of the seed laser entering the elliptical cylinder gain medium through the first end face of the elliptical cylinder gain medium;

[0030] The second end face of the elliptical cylinder gain medium is used to output the amplified seed laser.

[0031] The beneficial effects of the present invention are as follows:

[0032] In the present invention, the elliptical cylinder gain medium absorbs the pump light. When the cross-sectional area in the light passing direction is the same, compared with the rod-shaped gain medium, the elliptical cylinder gain medium increases the incident aperture of the pump light, improves the laser damage power, increases the heat dissipation area, increases the overall gain of the elliptical cylinder gain medium, and effectively improves the laser power; compared with the slab gain medium, the elliptical beam is more easily matched with the circular structure of the telescope focusing lens, avoiding the waste of the beam at the four corners of the light spot and the waste of the lens aperture, and effectively improving the utilization rate of the laser. Description of the Drawings

[0033] The following further describes in detail the specific embodiments of the present invention in conjunction with the accompanying drawings.

[0034] Figure 1 The structural schematic diagram of the large-surface pumped elliptical cylinder laser device in the first embodiment of the present invention is shown;

[0035] Figure 2 The optical path schematic diagram of the pump light in the first embodiment of the present invention is shown;

[0036] Figure 3 The structural schematic diagram of the end-face pumped elliptical cylinder laser device in the second embodiment of the present invention is shown;

[0037] Figure 4 The structural schematic diagram of the large-surface pumped laser amplifier in the third embodiment of the present invention is shown;

[0038] Figure 5 The structural schematic diagram of the end-face pumped laser amplifier in the fourth embodiment of the present invention is shown. Specific Embodiments

[0039] To more clearly illustrate the present invention, the following further describes the present invention in conjunction with the preferred embodiments and the accompanying drawings. Similar components in the drawings are denoted by the same reference numerals. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0040] The first aspect of the present invention provides an elliptical cylinder laser device, which includes a pump source, an elliptical cylinder gain medium, a reflection module, a resonant cavity, a pump light shaping module, and a cooling sleeve. The pumping method of the pump source in the laser device is large-surface pumping. Among them,

[0041] The pump source is used to provide pump light to the large surface of the elliptical cylinder gain medium; the pump source includes at least one group of pump bar groups arranged at intervals along the axial direction of the elliptical cylinder gain medium on the large surface of the elliptical cylinder gain medium. A pump bar group includes a plurality of pump bars arranged at intervals along the circumferential direction of the elliptical cylinder gain medium, and the pump bars are used to provide pump light to the large surface of the elliptical cylinder gain medium;

[0042] The pump light shaping module is arranged between the pump source and the elliptical cylinder gain medium, and is used to shape the pump light output by the pump source into elliptical pump light, and the elliptical pump light enters the elliptical cylinder gain medium through the large surface of the elliptical cylinder gain medium.

[0043] The elliptical cylinder gain medium is doped with a material that can generate gain, which can be a crystal or ceramic doped with ions. The shape of the elliptical cylinder gain medium is elliptical cylinder-shaped, and the cross-section in the light passing direction is elliptical.

[0044] Among them, the spot shape of the elliptical pump light output after being shaped by the pump light shaping module is elliptical. The elliptical spot and the elliptical cross-section of the elliptical cylinder gain medium are both longer in the longitudinal direction than in the transverse direction; the size of the elliptical pump light incident on the elliptical cylinder gain medium is less than or equal to the size of the elliptical cross-section of the elliptical cylinder gain medium.

[0045] The reflection module is used to reflect the pump light emerging after being absorbed by the elliptical cylinder gain medium back to the elliptical cylinder gain medium, so that the elliptical cylinder gain medium can perform multi-pass absorption on the pump light to generate laser; the reflection module includes a plurality of reflection sub-module groups. A reflection sub-module group includes reflection sub-modules between adjacent pump bars in a pump bar group, and is used to achieve uniform distribution of the pump light emitted by the pump source and the pump light reflected by the reflection module. The material of the reflection module can be ceramic or other materials that can reflect pump light.

[0046] The resonant cavity includes a reflector on one side of the first end face of the elliptical cylinder gain medium and an output mirror on one side of the second end face of the elliptical cylinder gain medium. The resonant cavity is used to reflect and amplify the laser; the output mirror is used to output the amplified laser.

[0047] The cooling sleeve is wrapped around the large surface of the elliptical cylinder gain medium and is used to cool the elliptical cylinder gain medium.

[0048] The second aspect of the present invention provides an elliptical cylinder laser device, which includes a pump source, an elliptical cylinder gain medium, a pump light shaping module, a first plane mirror, a resonant cavity, and a cooling sleeve. The pumping method of the pump source in this laser device is end pumping;

[0049] The pump source is used to provide pump light to the first end face of the elliptical cylinder gain medium. The pump light enters the elliptical cylinder gain medium through the first end face of the elliptical cylinder gain medium after being reflected by the first plane mirror;

[0050] The pump light shaping module is arranged between the pump source and the first plane mirror, and is used to shape the pump light into elliptical pump light. The elliptical pump light enters the elliptical cylinder gain medium through the first end face of the elliptical cylinder gain medium after being reflected by the first plane mirror. The elliptical cylinder gain medium performs exponential absorption on the pump light to generate laser;

[0051] The resonant cavity includes a reflector on one side of the first end face of the elliptical cylinder gain medium and an output mirror on one side of the second end face of the elliptical cylinder gain medium. The resonant cavity is used to reflect and amplify the laser, and the output mirror is used to output the amplified laser.

[0052] The cooling sleeve is wrapped around the large surface of the elliptical cylinder gain medium and is used to cool the elliptical cylinder gain medium.

[0053] The first plane mirror is arranged between the reflector and the elliptical cylinder gain medium and is used to reflect the pump light and transmit the laser.

[0054] In the third aspect of the present invention, a laser amplifier is provided. The laser amplifier includes a seed source, an elliptical cylinder gain medium, a pump source, and a reflection module. Among them, the pumping method of the pump source in the laser amplifier is large-area pumping;

[0055] The pump source is used to provide pump light to the large surface of the elliptical cylinder gain medium; the seed source is arranged on one side of the first end face of the elliptical cylinder gain medium and is used to provide seed laser to the first end face of the elliptical cylinder gain medium; the reflection module is used to reflect the pump light emitted after being absorbed by the elliptical cylinder gain medium back to the elliptical cylinder gain medium, so that the elliptical cylinder gain medium performs multi-pass absorption on the pump light and then amplifies the energy of the seed laser incident through the first end face of the elliptical cylinder gain medium; the amplified seed laser is output through the second end face of the elliptical cylinder gain medium.

[0056] The laser amplifier further includes a pump light shaping module, which is arranged between the pump source and the elliptical cylinder gain medium and is used to shape the pump light into elliptical pump light.

[0057] The laser amplifier further includes a seed source shaping module. In this embodiment, the seed source shaping module is a seed source shaping lens group arranged between the seed source and the elliptical cylinder gain medium and is used to shape the seed laser emitted by the seed source to obtain elliptical seed laser; the elliptical seed laser enters the elliptical cylinder gain medium through the first end face of the elliptical cylinder gain medium.

[0058] The laser amplifier further includes a cooling sleeve covering the elliptical cylinder gain medium and is used to cool the elliptical cylinder gain medium.

[0059] In the fourth aspect of the present invention, a laser amplifier is provided. The laser amplifier includes a pump source, a seed source, an elliptical cylinder gain medium, and a second plane mirror. Among them, the pumping method of the pump source in the laser amplifier is end pumping;

[0060] The pump source is used to provide pump light to the first end face of the elliptical cylinder gain medium, the seed source is arranged on one side of the first end face of the elliptical cylinder gain medium and is used to provide seed laser to the first end face of the elliptical cylinder gain medium; the second plane mirror is arranged between the seed source and the elliptical cylinder gain medium and is coated with a pump light reflection film and a seed laser transmission film, and is used to reflect the pump light and transmit the seed laser; the pump light enters the elliptical cylinder gain medium through the first end face of the elliptical cylinder gain medium, and the elliptical cylinder gain medium performs exponential absorption on the pump light and then amplifies the energy of the seed laser entering the elliptical cylinder gain medium through the first end face of the elliptical cylinder gain medium; the second end face of the elliptical cylinder gain medium is used to output the amplified seed laser.

[0061] According to the positional relationship between the pump source and the seed source, the second plane mirror may also be coated with a pump light transmission film and a seed laser reflection film to transmit the pump light and reflect the seed laser.

[0062] The laser amplifier further includes a pump light shaping module and a seed source shaping module. The pump light shaping module is disposed between the pump source and the second plane mirror and is configured to shape the pump light to obtain an elliptical pump light, and the elliptical pump light enters the elliptical cylindrical gain medium through the first end face of the elliptical cylindrical gain medium; the seed source shaping module is disposed between the seed source and the second plane mirror and is configured to shape the seed source to obtain an elliptical seed laser; the elliptical seed laser passes through the second plane mirror and then enters the elliptical cylindrical gain medium through the first end face of the elliptical cylindrical gain medium.

[0063] The laser amplifier further includes a cooling sleeve covering the elliptical cylindrical gain medium for cooling the elliptical cylindrical gain medium.

[0064] In a specific embodiment, Figure 1 is a schematic structural diagram of a laser device with large surface pumping in this embodiment. The laser device includes an elliptical cylindrical gain medium 1, a pump source 2, a pump light shaping module (the pump light shaping module is not shown in Figure 1 ), a reflection module 3, a cooling sleeve 4, and a resonant cavity. Among them,

[0065] The pump source 2 is configured to provide pump light to the large surface of the elliptical cylindrical gain medium 1; the pump source 2 includes at least one set of pump bar groups arranged at intervals along the axial direction of the elliptical cylindrical gain medium on the large surface of the elliptical cylindrical gain medium 1. One pump bar group includes a plurality of pump bars arranged at intervals along the circumferential direction of the elliptical cylindrical gain medium 1, and the pump bars are configured to provide pump light to the large surface of the elliptical cylindrical gain medium 1;

[0066] The pump light shaping module is disposed between the pump source 2 and the elliptical cylindrical gain medium 1 and is configured to shape the pump light output by the pump source 2 into an elliptical pump light, and the elliptical pump light enters the interior of the elliptical cylindrical gain medium 1 through the large surface of the elliptical cylindrical gain medium 1;

[0067] The reflection module 3 is used to reflect the pump light emitted after being absorbed by the elliptical cylinder gain medium 1 back to the elliptical cylinder gain medium 1, so that the elliptical cylinder gain medium 1 can perform multi-pass absorption on the pump light to generate laser light; the reflection module 3 includes a plurality of reflection sub-module groups, and one reflection sub-module group includes reflection sub-modules located between adjacent pump bars in a pump bar group, which is used to achieve uniform distribution of the pump light emitted by the pump source 2 and the pump light reflected by the reflection module 3. In this embodiment, the material of the reflection module 3 is a ceramic block, and the reflection sub-modules and the pump bars are arranged alternately at equal intervals. The ceramic block is used to reflect the pump light emitted after being absorbed by the elliptical cylinder gain medium 1, so that it is reflected into the elliptical cylinder gain medium 1 again, so that the elliptical cylinder gain medium 1 can perform multi-pass absorption on the pump light to generate laser light; in this embodiment, the pump bars and the reflection sub-modules are arranged alternately at equal intervals along the large surface of the elliptical cylinder gain medium 1, so as to achieve uniform distribution of the pump light emitted by the pump source 2 and the pump light reflected by the reflection module 3; the reflection sub-modules and the pump bars can also be arranged alternately at unequal intervals according to actual needs. The resonant cavity includes a reflector 5 arranged on the first end face of the elliptical cylinder gain medium 1 and an output mirror 6 arranged on the second end face of the elliptical cylinder gain medium 1. The resonant cavity is used to reflect and amplify the laser light, and the amplified laser light is output through the output mirror 6.

[0068] The cooling sleeve 4 is coated on the large surface of the elliptical cylinder gain medium and is used to cool the elliptical cylinder gain medium; the cooling sleeve 4 is a cooling material that can transmit pump light. The cooling sleeve 4 continuously absorbs the heat generated by the elliptical cylinder gain medium 1 to ensure that the elliptical cylinder gain medium 1 operates stably in a suitable temperature environment and guarantee the overall performance of the laser oscillator.

[0069] The pump light provided by the pump source 2 is incident through the large surface of the elliptical cylinder gain medium 1. After being absorbed, the pump light is emitted to the reflection module 3. After being reflected by the reflection module 3, the pump light is incident into the elliptical cylinder gain medium 1 again through the large surface of the elliptical cylinder gain medium 1 and is absorbed. After being absorbed, the pump light is emitted to the reflection module 3 again. After being reflected by the reflection module 3, it enters the elliptical cylinder gain medium 1 and is absorbed. Such multi-pass absorption is repeated until the pump light is completely absorbed, thereby exciting the elliptical cylinder gain medium 1 to achieve population inversion. The elliptical cylinder gain medium 1 amplifies the laser on the basis of population inversion.

[0070] The resonant cavity includes a reflector 5 on one side of the first end face of the elliptical cylinder gain medium 1 and an output mirror 6 on one side of the second end face of the elliptical cylinder gain medium 1. The resonant cavity is used to reflect and amplify the laser light, and the output mirror 6 is used to output the amplified laser light. Under the action of the resonant cavity, the gain-amplified laser light continuously oscillates and feedbacks in the resonant cavity; the reflector 5 reflects the laser light back into the medium, so that the light travels back and forth in the resonant cavity many times, further enhancing the amplification effect. After the oscillation feedback amplification of the resonant cavity, a stable amplified laser beam is output from the output mirror 6.

[0071] Figure 2 It is a schematic optical path diagram of the pump light. The longitudinal direction of the elliptical cross-section of the elliptical cylinder gain medium 1 is greater than the transverse direction. The cooling sleeve 4 is coated on the large surface of the elliptical cylinder gain medium 1. The pump sources 2 and the reflection modules 3 are arranged alternately on the outer side of the cooling sleeve 4. The pump light provided by the pump source 2 is incident on the elliptical cylinder gain medium 1 from the large surface of the elliptical cylinder gain medium 1.

[0072] Specifically, the pump light provided by the pump source 2 is shaped into elliptical pump light by the pump light shaping module, and the elliptical pump light is incident into the elliptical cylinder gain medium 1 through the large surface of the elliptical cylinder gain medium 1; the pump light undergoes exponential absorption through the elliptical cylinder gain medium 1 (see ① in Figure 2 ), and then is incident on the corresponding reflection module 3 at the corresponding position. The reflection module 3 reflects the pump light back into the elliptical cylinder gain medium 1 for exponential absorption again (see ② in Figure 2 ). The pump light after experiencing the second exponential absorption by the elliptical cylinder gain medium 1 exits to the corresponding reflection module 3, is reflected by the reflection module 3 and enters the elliptical cylinder gain medium 1 again. The pump light after being absorbed by the elliptical cylinder gain medium 1 again (see ③ in Figure 2 ) exits to the corresponding reflection module 3 again, and the pump light is reflected back into the elliptical cylinder gain medium 1 by the reflection of the reflection module 3 for exponential absorption. This cycle repeats, and the pump light forms multi-pass absorption, increasing the absorption efficiency of the pump light.

[0073] In this embodiment, the reflection module 3 reflects the pump light to the elliptical cylinder gain medium 1, realizing multi-pass absorption of the pump light in the elliptical cylinder gain medium 1, and effectively increasing the overall gain of the elliptical cylinder gain medium 1.

[0074] In the second specific embodiment, Figure 3 It is a schematic structural diagram of a laser device with end pumping provided in the second embodiment. The laser device includes an elliptical cylinder gain medium 1, a pump source 21, a cooling sleeve 4, a pump light shaping module 9, a first plane mirror 10, and a resonant cavity. In this embodiment, only the differences from the first embodiment are discussed, and the same parts are not discussed again.

[0075] The pump source 21 is used to provide pump light to the first end face of the elliptical cylinder gain medium 1. The pump source 21 can be at least one set of pump bar groups or semiconductor lasers. The pump light shaping module 9 is arranged between the first plane mirror 10 and the pump source 21 and is used to shape the pump light emitted by the pump source 21 to obtain elliptical pump light. The first plane mirror 10 is arranged between the reflecting mirror 5 and the elliptical cylinder gain medium 1 and is used to reflect the shaped pump light and transmit the laser. The elliptical pump light is incident into the elliptical cylinder gain medium 1 through the first end face of the elliptical cylinder gain medium 1 after being reflected by the first plane mirror 10. The elliptical pump light is reflected inside the elliptical cylinder gain medium 1 so that the elliptical cylinder gain medium 1 performs exponential absorption on the pump light. After the pump light is completely absorbed, laser is generated. The resonant cavity includes a reflecting mirror 5 arranged on one side of the first end face of the elliptical cylinder gain medium 1 and an output mirror 6 arranged on one side of the second end face of the elliptical cylinder gain medium 1. Under the action of the resonant cavity, the laser after gain amplification oscillates and feeds back continuously in the cavity. The reflecting mirror 5 reflects the laser back into the elliptical cylinder gain medium 1, enabling the laser to make multiple round trips in the resonant cavity, further enhancing the amplification effect. The laser amplified through the oscillation and feedback of the resonant cavity is output from the output mirror 6. Among them, the first end face of the elliptical cylinder gain medium 1 is the end face close to the pump source 21, and the second end face is the end face far from the pump source 21.

[0076] In the third specific embodiment, Figure 4 FIG. is a schematic structural diagram of a laser amplifier in the third embodiment. The pumping method of the pump source in this laser amplifier is large-area pumping. In the third embodiment, only the differences from the first embodiment are described, and the same parts are not described again.

[0077] This laser amplifier includes a seed source 7, an elliptical cylinder gain medium 1, a pump source 2, a reflection module 3, a cooling sleeve 4, and a seed source shaping module 8, where

[0078] The pump source 2 is used to provide pump light to the large face of the elliptical cylinder gain medium 1. The pump light is shaped into elliptical pump light through a pump light shaping module (the pump light shaping module is not shown in Figure 4 ). The elliptical pump light is incident into the elliptical cylinder gain medium 1 through the large face of the elliptical cylinder gain medium 1. After the pump light is absorbed by the elliptical cylinder gain medium 1, it exits to the reflection module 3. After being reflected by the reflection module 3, the pump light is incident into the elliptical cylinder gain medium 1 again through the large face of the elliptical cylinder gain medium 1 and is absorbed. Such multi-pass absorption is repeated until the pump light is completely absorbed. The energy of the pump light is used to excite atoms or ions in the elliptical cylinder gain medium 1 to make them reach the excited state, thereby storing energy and generating gain.

[0079] The seed source 7 is arranged on one side of the first end face of the elliptical cylinder gain medium 1 and is used to provide seed laser to the first end face of the elliptical cylinder gain medium 1. The seed laser is shaped by the seed source shaping module 8 to obtain an elliptical seed laser, and the elliptical seed laser enters the interior of the elliptical cylinder gain medium 1 through the first end face of the elliptical cylinder gain medium 1; the reflection module 3 is used to reflect the pump light emitted after being absorbed by the elliptical cylinder gain medium 1 back to the elliptical cylinder gain medium 1, so that the elliptical cylinder gain medium 1 performs multi-pass absorption on the pump light and amplifies the energy of the seed laser incident through the first end face of the elliptical cylinder gain medium 1; the amplified seed laser is output through the second end face of the elliptical cylinder gain medium 1.

[0080] The seed laser provided by the seed source 7 is a circular seed laser. The circular seed laser output by the seed source 7 is shaped by the seed source shaping lens group 8 to output an elliptical seed laser; the elliptical seed laser enters the elliptical cylinder gain medium 1 through the first end face of the elliptical cylinder gain medium 1. Through the gain effect of the elliptical cylinder gain medium 1, the light intensity is amplified to form laser amplification to meet the laser requirements in different application scenarios. Among them, the spot of the elliptical seed laser shaped and output by the seed source shaping lens group 8 and the elliptical cross-section of the elliptical cylinder gain medium 1 are both longer in the longitudinal direction than in the transverse direction. The spot size of the elliptical seed laser incident on the elliptical cylinder gain medium 1 is less than or equal to the size of the elliptical cross-section of the elliptical cylinder gain medium 1.

[0081] The cooling sleeve 4 is wrapped around the large surface of the elliptical cylinder gain medium 1 and is used to cool the elliptical cylinder gain medium 1.

[0082] In the fourth specific embodiment, the pumping method of the pump source in the laser amplifier is end pumping. Figure 5 It is a schematic structural diagram of a laser amplifier with end pumping. The laser amplifier includes a seed source 7, an elliptical cylinder gain medium 1, a pump source 21, a pump light shaping module 9, a seed source shaping module 8, a cooling sleeve 4, and a second plane mirror 11. Among them, both the pump source 21 and the seed source 7 are arranged on one side of the first end face of the elliptical cylinder gain medium 1.

[0083] The pump source 21 can be at least one group of pump bar groups or semiconductor lasers. The pump source 21 is arranged on one side of the first end face of the elliptical cylinder gain medium 1 and is used to provide pump light to the first end face of the elliptical cylinder gain medium 1; the pump light shaping module 9 is arranged between the pump source 21 and the second plane mirror 11 and is used to shape the pump light into an elliptical pump light; the second plane mirror 11 is arranged between the elliptical cylinder gain medium 1 and the seed source 7 and is coated with a pump light reflection film and a seed laser transmission film, and is used to reflect the pump light and transmit the seed laser; the elliptical pump light enters the elliptical cylinder gain medium 1 through the first end face of the elliptical cylinder gain medium 1 after being reflected by the second plane mirror 11.

[0084] The seed source 7 is arranged on one side of the first end face of the elliptical cylinder gain medium 1 and is used to provide seed laser to the first end face of the elliptical cylinder gain medium 1. The seed source shaping module 8 is arranged between the seed source 7 and the second plane mirror 11 and is used to shape the seed laser into elliptical seed laser. The elliptical seed laser passes through the second plane mirror 11 and then enters the elliptical cylinder gain medium 1 through the first end face of the elliptical cylinder gain medium 1;

[0085] After the elliptical pump light enters the interior of the elliptical cylinder gain medium 1 through the first end face of the elliptical cylinder gain medium 1, the elliptical cylinder gain medium 1 performs exponential absorption on the elliptical pump light and then amplifies the energy of the seed laser incident through the first end face of the elliptical cylinder gain medium 1. The amplified seed laser is output through the second end face of the elliptical cylinder gain medium 1.

[0086] According to the positional relationship between the pump source 21 and the seed source 7, the second plane mirror 11 can also be coated with a pump light transmission film and a seed laser reflection film to transmit the pump light and reflect the seed laser.

[0087] In the present invention, the elliptical cylinder gain medium absorbs the pump light. When the cross-sectional area in the light passing direction is the same, compared with the rod-shaped gain medium, the elliptical cylinder gain medium increases the incident aperture, improves the laser damage power, increases the heat dissipation area, and improves the laser power; compared with the slab gain medium, the elliptical pump light is easier to shape than the square pump light. After shaping, the elliptical pump light is incident on the elliptical cylinder gain medium, effectively improving the utilization rate of the laser; secondly, in the application of high-power lasers, using an elliptical beam can also better match the circular structure of the telescope focusing lens, avoiding the waste of the beam at the four corners of the light spot and the waste of the lens aperture; and the elliptical cylinder gain medium does not require Zigzag transmission compared with the slab gain medium, reducing the requirements for side processing, having the advantages of lower processing difficulty and simple structure, being able to directly use O-ring sealing without complex welding heat sink technology, simplifying the operation process and reducing the manufacturing cost, having a high laser output power and efficiency, and being suitable for high-power laser applications.

[0088] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention 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. Therefore, it should not be construed as a limitation to the present invention. Unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0089] It should also be noted that in the description of the present invention, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variation thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the existence of additional identical elements in the process, method, article or device comprising the said element.

[0090] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation manners here. Any obvious changes or modifications derived from the technical solutions of the present invention still fall within the protection scope of the present invention.

Claims

1. An elliptical column laser device, characterized in that: The laser device includes a pump source, an elliptical column gain medium, a reflection module and a resonant cavity, wherein: The pump source is used to provide pump light to the large surface of the elliptical cylindrical gain medium; The reflection module is used to reflect the pump light emitted after being absorbed by the elliptical cylindrical gain medium back to the elliptical cylindrical gain medium, so that the elliptical cylindrical gain medium generates laser light after multi-pass absorption of the pump light; The resonant cavity comprises a reflector located at a first end face side of the elliptical cylindrical gain medium and an output mirror located at a second end face side of the elliptical cylindrical gain medium. The resonant cavity is used to reflect and amplify laser light, and the output mirror is used to output the amplified laser light.

2. The laser device according to claim 1, characterized in that The pump source includes at least one group of pump bars arranged at intervals along the axial direction of the elliptical cylindrical gain medium on the large surface of the elliptical cylindrical gain medium. One pump bar group includes a plurality of pump bars arranged at intervals along the circumferential direction of the elliptical cylindrical gain medium. The pump bars are used to provide pump light to the large surface of the elliptical cylindrical gain medium.

3. The laser device according to claim 2, characterized in that: The reflection module includes a plurality of reflection sub-module groups, and one reflection sub-module group includes a reflection sub-module located between adjacent pump bars in one pump bar group.

4. The laser device according to claim 1, characterized in that The laser device also includes a cooling sleeve covering a large surface of the elliptical cylindrical gain medium.

5. The laser device according to claim 1, characterized in that The laser device further comprises a pump light shaping module, which is arranged between the pump source and the elliptical column gain medium and is used for shaping the pump light into an elliptical pump light.

6. An elliptical column laser device, characterized in that: The laser device comprises a pump source, an elliptical column gain medium and a resonant cavity. The pump source is used to provide pump light to the first end face of the elliptical cylindrical gain medium; The elliptical cylindrical gain medium is used to exponentially absorb the pump light to generate laser light; The resonant cavity comprises a reflector located at a first end face side of the elliptical cylindrical gain medium and an output mirror located at a second end face side of the elliptical cylindrical gain medium. The resonant cavity is used to reflect and amplify laser light, and the output mirror is used to output the amplified laser light.

7. The laser device according to claim 6, characterized in that The laser device further includes a first plane mirror, which is disposed between the reflector and the elliptical column gain medium, and is used for reflecting the pump light and transmitting the laser light.

8. The laser device according to claim 7, characterized in that The laser device further comprises a pump light shaping module, which is arranged between the pump source and the first plane mirror and is used for shaping the pump light into an elliptical pump light.

9. A laser amplifier, characterized in that: The laser amplifier includes a seed source, an elliptical column gain medium, a pump source and a reflection module, wherein: The pump source is used to provide pump light to the large surface of the elliptical cylindrical gain medium; The seed source is used to provide a seed laser to the first end face of the elliptical cylindrical gain medium; The reflection module is used to reflect the pump light emitted after being absorbed by the elliptical cylindrical gain medium back to the elliptical cylindrical gain medium, so that the elliptical cylindrical gain medium absorbs the pump light in multiple passes and then amplifies the energy of the seed laser incident through the first end face of the elliptical cylindrical gain medium; The second end face of the elliptical cylindrical gain medium is used to output the amplified seed laser.

10. A laser amplifier, characterized in that: The laser amplifier comprises a pump source, a seed source, a second plane mirror and an elliptical cylindrical gain medium, wherein: The pump source is used to provide pump light to the first end face of the elliptical cylindrical gain medium; The seed source is used to provide a seed laser to the first end face of the elliptical cylindrical gain medium; The second plane mirror is used to reflect the pump light and transmit the seed laser, or reflect the seed laser and transmit the pump light; After the elliptical cylindrical gain medium exponentially absorbs the pump light, the seed laser entering the elliptical cylindrical gain medium through the first end face of the elliptical cylindrical gain medium is energy amplified; The second end face of the elliptical cylindrical gain medium is used to output the amplified seed laser.

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