Intracavity scattering multi-pass pumping disc laser device and laser amplifier

Abstract

The invention discloses an intracavity scattering multi-pass pump disc laser device and a laser amplifier, the laser device comprises a pump light source, a reflection cavity, a disc laser medium and an output mirror, the disc laser medium is arranged in the reflection cavity, and the pump light source is used for providing pump light; the reflection cavity is used for reflecting the emergent pump light absorbed by the disc laser medium back to the disc laser medium, so that the disc laser medium performs multi-pass absorption on the pump light to generate laser; a first large surface, far away from the output mirror, of the disc laser medium and the output mirror form a resonant cavity, and the resonant cavity is used for reflecting, oscillating and amplifying laser; and the output mirror is used for outputting laser. According to the invention, the pump light is reflected through the side wall of the reflection cavity, so that the pump light passes through the disc laser medium for multiple times for multi-pass absorption, the effective absorption length of the disc laser medium is increased, uniform pumping is realized, the laser efficiency is improved, and the overall gain of the disc laser medium is effectively increased.

Description

Technical Field

[0001] The present invention relates to the field of solid-state lasers, and more specifically, to an intracavity scattering multi-pass pumped disk laser device and a laser amplifier. Background Art

[0002] With the continuous advancement of laser technology, disk lasers have demonstrated superior performance in many fields, especially in high-power lasers, precision machining and material processing. However, although the thin-disk design of disk lasers brings the advantages of small size and light weight, it is also accompanied by some technical challenges.

[0003] The disk generally has a large aperture, which is very suitable for the generation of ultra-strong ultra-short pulse lasers. However, it is thin and has a short absorption path for pump light, resulting in low absorption efficiency and laser efficiency of pump light, which limits its performance in high-power laser applications. To solve this problem, researchers have proposed increasing pump absorption to ensure that more pump light is absorbed to improve the overall efficiency of disk lasers. Traditional pumping techniques, such as the use of multiple reflectors or refractors, usually rely on direct light sources. This method faces problems of insufficient absorption and light loss in disk lasers, and the device structure is complex and the manufacturing cost is high. Summary of the invention

[0004] The present invention provides an intracavity scattering multi-pass pumping disk laser device and a laser amplifier to solve at least one of the problems existing in the prior art.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The first aspect of the present invention provides an intracavity scattering multi-pass pumped disk laser device, the device comprising a pump light source, a reflective cavity, a disk laser medium and an output mirror, wherein the disk laser medium is arranged inside the reflective cavity,

[0007] The pump light source is used to provide pump light;

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

[0009] The first large surface of the disk laser medium away from the output mirror and the output mirror form a resonant cavity, and the resonant cavity is used for reflecting oscillating and amplifying laser light;

[0010] The output mirror is used to output laser light.

[0011] Optionally, the reflection cavity includes a reflection cavity side wall, a reflection cavity cover and a cooling module, the reflection cavity side wall is plated with a reflective material for reflecting pump light, and the cooling module serves as the bottom of the reflection cavity and is used to cool the disk laser medium fixed on the cooling module.

[0012] Optionally, the reflective cavity cover is provided with a through hole for incident pump light, a quartz lens is provided at the through hole, and the quartz lens is plated with a pump light transmission film.

[0013] Optionally, a non-through hole area of ​​the reflective cavity cover is plated with a laser transmissive film and a pump light reflective film.

[0014] Optionally, the first large surface of the disk laser medium is coated with a pump light reflecting film and a laser reflecting film, and the second large surface opposite to the first large surface is coated with a pump light transmitting film.

[0015] Optionally, the device also includes a first plane mirror, which is arranged between the reflection cavity and the output mirror, and is coated with a pump light reflection film and a laser transmission film. The first plane mirror is used to reflect the pump light emitted by the pump light source into the reflection cavity and transmit the laser to the output mirror.

[0016] Optionally, the laser device includes a second plane mirror arranged inside the reflection cavity, the second plane mirror is coated with a pump light transmission film and a laser reflection film, and a laser transmission area is arranged on the side wall of the reflection cavity for transmitting the output laser to the output mirror.

[0017] Optionally, the reflective cavity cover of the reflective cavity comprises a first through hole and a plurality of second through holes surrounding the first through hole, the first through hole is used to transmit laser light, and the second through holes are used to transmit pump light.

[0018] A second aspect of the present invention provides an intracavity scattering multi-pass pumped laser amplifier, the laser amplifier comprising a pump light source, a seed laser source, a reflective cavity and a disk laser medium, wherein the disk laser medium is arranged inside the reflective cavity.

[0019] The pump light source is used to provide pump light;

[0020] The seed laser source is used to provide seed laser;

[0021] The reflective cavity comprises a reflective cavity side wall and a reflective cavity cover, wherein the reflective cavity side wall is provided with a first through hole and a second through hole, and the reflective cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium absorbs the pump light in multiple passes and then amplifies the energy of the seed laser entering the reflective cavity through the first through hole;

[0022] The second through hole is used to output the seed laser after energy amplification.

[0023] A third aspect of the present invention provides an intracavity scattering multi-pass pumped laser amplifier, the laser amplifier comprising a pump light source, a hollow seed laser source, a reflective cavity and a disk laser medium, wherein the disk laser medium is arranged inside the reflective cavity.

[0024] The pump light source is used to provide pump light;

[0025] The hollow seed laser source is used to provide hollow seed laser;

[0026] The reflection cavity comprises a reflection cavity side wall and a reflection cavity cover, wherein the reflection cavity side wall is provided with a third through hole, and the reflection cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium absorbs the pump light in multiple passes and then amplifies the energy of the hollow seed laser entering the reflection cavity through the third through hole;

[0027] The reflective cavity cover is provided with a fourth through hole, and the fourth through hole is used to output the amplified hollow seed laser.

[0028] The beneficial effects of the present invention are as follows:

[0029] The present invention utilizes the reflection of the pump light by the side wall of the reflection cavity to make the pump light pass through the disk laser medium for multiple times, and performs multi-pass absorption of the pump light, thereby increasing the effective absorption length of the disk laser medium, achieving uniform pumping, improving laser efficiency, and effectively increasing the overall gain of the disk laser medium to achieve a higher laser amplification effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0031] Figure 1 A schematic structural diagram of a disk laser device according to a first embodiment of the present invention is shown;

[0032] Figure 2 A schematic diagram showing the optical path of the disk laser medium and the pump light in the reflective cavity according to the first embodiment of the present invention;

[0033] Figure 3 A schematic diagram showing the structure of a disk laser device according to a second embodiment of the present invention;

[0034] Figure 4 A schematic structural diagram of a disk laser device according to a third embodiment of the present invention is shown;

[0035] Figure 5 A schematic diagram showing a pump light incident through hole and a laser exit through hole of a third embodiment of the present invention;

[0036] Figure 6 A schematic diagram showing the structure of a laser amplifier according to a fourth embodiment of the present invention;

[0037] Figure 7 A schematic structural diagram of a laser amplifier according to a fifth embodiment of the present invention is shown. DETAILED DESCRIPTION

[0038] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred embodiments and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0039] The first aspect of the present invention provides an intracavity scattering multi-pass pumped disk laser device, the laser device comprises a pump light source, a reflection cavity, a disk laser medium and an output mirror, wherein the disk laser medium is arranged inside the reflection cavity,

[0040] The pump light source is used to provide pump light, and the pump light source can be a semiconductor laser; the disk laser medium is arranged inside the reflection cavity, and the disk laser medium is used to absorb part of the pump light and emit the unabsorbed pump light to the reflection cavity;

[0041] The reflection cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium generates laser after multi-pass absorption of the pump light;

[0042] The first large surface of the disk laser medium on the side away from the output mirror and the output mirror form a resonant cavity, and the resonant cavity is used for reflecting the oscillation and amplifying the laser;

[0043] The output mirror is also used to output the laser.

[0044] The reflective cavity comprises a reflective cavity side wall, a reflective cavity cover and a cooling module. The reflective cavity side wall is plated with a reflective material for reflecting pump light, and the reflective material can be metal or ceramic. The reflective cavity cover is provided with a through hole for pump light incidence, and a quartz lens is arranged at the through hole. The quartz lens is plated with a pump light transmission film to increase the pump light entering the reflective cavity. The non-through hole area of ​​the reflective cavity cover is plated with a pump light reflection film and a laser transmission film to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, and transmit the laser. The cooling module serves as the bottom of the reflective cavity. The cooling module is a cooling heat sink, which is used to cool the disk laser medium fixed on the cooling heat sink.

[0045] The disk laser medium is a thin disk laser medium, and a pump light reflection film and a laser reflection film are plated on the first large surface of the disk laser medium, and a pump light transmission film is plated on the second large surface opposite to the first large surface, so that the disk laser medium can fully absorb the pump light. The first large surface is the large surface of the disk laser medium away from the output mirror, and the second large surface is the large surface of the disk laser medium close to the output mirror.

[0046] The laser device also includes a first plane mirror, which is used to inject pump light into the interior of the reflective cavity through the through hole on the reflective cavity cover. The first plane mirror is arranged between the reflective cavity and the output mirror, and is coated with a pump light reflective film to couple the pump light emitted by the pump light source into the interior of the reflective cavity through the first plane mirror; the first plane mirror is also coated with a laser transmission film to allow the laser to be output from the output mirror through the first plane mirror.

[0047] The laser device also includes a second plane mirror, which is arranged inside the reflection cavity and coated with a pump light transmission film and a laser reflection film; a laser transmission area is arranged on the side wall of the reflection cavity to transmit the output laser to the output mirror.

[0048] The reflective cavity cover of the laser device may also include a first through hole and a plurality of second through holes surrounding the first through hole, wherein the first through hole is used to transmit laser light, and the second through holes are used to transmit pump light, wherein the first through hole is a laser emission through hole, and the second through hole is a pump light incident through hole.

[0049] A second aspect of the present invention provides an intracavity scattering multi-pass pumped laser amplifier, the laser amplifier comprising a pump light source, a seed laser source, a reflective cavity and a disk laser medium, wherein the disk laser medium is arranged inside the reflective cavity, the laser amplifier further comprising a first plane mirror, the first plane mirror being arranged outside the reflective cavity,

[0050] The pump light source is used to provide pump light; the seed laser source is used to provide seed laser; the first plane mirror is coated with a pump light reflection film, which is used to reflect the pump light emitted by the pump light source into the reflection cavity; the reflection cavity includes a reflection cavity side wall and a reflection cavity cover, and the reflection cavity side wall is provided with a first through hole and a second through hole, and the reflection cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium absorbs the pump light in multiple passes to amplify the energy of the seed laser entering the reflection cavity through the first through hole; the reflection cavity cover is provided with a through hole for the pump light to be incident; the seed laser enters the disk laser medium inside the reflection cavity through the first through hole of the reflection cavity side wall, and the seed laser is energy-amplified, and the seed laser after energy amplification is output through the second through hole. Among them, the first through hole is the through hole for incident seed laser, and the second through hole is the through hole for emitting seed laser.

[0051] The laser amplifier also includes a cooling module, which serves as the bottom of the reflection cavity. The cooling module is a cooling heat sink and is used to cool the disk laser medium fixed on the cooling heat sink.

[0052] A third aspect of the present invention provides an intracavity scattering multi-pass pump laser amplifier, the laser amplifier comprising a pump light source, a hollow seed laser source, a reflective cavity and a disk laser medium, wherein the disk laser medium is arranged inside the reflective cavity, the laser amplifier further comprising a second plane mirror, the second plane mirror being arranged between the reflective cavity and the pump light source;

[0053] The pump light source is used to provide pump light; the hollow seed laser source is used to provide hollow seed laser; the second plane mirror is coated with a pump light transmission film and a laser reflection film, and is used to transmit the pump light emitted by the pump light source into the reflection cavity; the reflection cavity includes a reflection cavity side wall and a reflection cavity cover, and the reflection cavity side wall is provided with a third through hole, and the reflection cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium absorbs the pump light in multiple passes to amplify the energy of the hollow seed laser entering the reflection cavity through the third through hole;

[0054] The reflective cavity cover is provided with a fourth through hole, and the fourth through hole is used for incident pump light and hollow seed laser after transmission energy amplification;

[0055] The hollow seed laser enters the disk laser medium inside the reflective cavity through the third through hole on the side wall of the reflective cavity, and the energy of the hollow seed laser is amplified. The energy-amplified hollow seed laser is output from the reflective cavity to the second plane mirror through the fourth through hole on the reflective cavity cover, and the energy-amplified hollow seed laser is output through the second plane mirror. Among them, the third through hole is the through hole for incident hollow seed laser, and the fourth through hole is the through hole for incident pump light and transmission of energy-amplified hollow seed laser.

[0056] The laser device of the present invention utilizes a reflective cavity structure, and a pump light source emits pump light, which is coupled into the reflective cavity through a quartz lens on the reflective cavity cover, and the pump light enters the disc laser medium through the second largest surface of the disc laser medium for pumping. The pump light is incident from the second largest surface of the disc laser medium into the disc laser medium, and after being absorbed by the disc laser medium, it is reflected by the first large surface and absorbed by the disc laser medium again. After the pump light is emitted from the second large surface, it is reflected by the side wall of the reflective cavity to the disc laser medium, and is incident again through the second largest surface of the disc laser medium and absorbed, and this is repeated for multiple times for multi-pass absorption until the pump light is almost completely absorbed. In this way, the pump light is reflected by the side wall of the reflective cavity so that the pump light passes through the disc laser medium multiple times, and the pump light is absorbed multiple times, thereby increasing the effective absorption length of the disc laser medium, achieving uniform pumping, and improving the laser efficiency, thereby solving the problem of low absorption efficiency of the pump light and low laser efficiency caused by the thin thickness of the disc laser medium and the short absorption path of the pump light. Furthermore, the laser device of the present invention has a simple structure and is easy to use, and solves the problems of light loss and high cost caused by the configuration of multiple reflectors or refractors in traditional pumping technology.

[0057] In a first specific embodiment, Figure 1 The present embodiment is an intracavity scattering multi-pass pumped disk laser device, which includes a pump light source 1, a first plane mirror 2, a reflection cavity 3, a disk laser medium 4, and an output mirror 5 arranged along the optical path. The first plane mirror 2 is arranged between the output mirror 5 and the reflection cavity 3, the disk laser medium 4 is arranged inside the reflection cavity 3, the reflection cavity 3 includes a reflection cavity side wall 31, a reflection cavity cover 32, and a cooling heat sink 7, a pump light through hole 6 is arranged on the reflection cavity cover 32, and a quartz lens is arranged at the through hole, and the cooling heat sink 7 is arranged on the first large surface of the disk laser medium 4 as the bottom of the reflection cavity 3.

[0058] The pump light source 1 is a semiconductor laser, which is used to emit pump light; the first plane mirror 2 is coated with a pump light reflecting film, and the first plane mirror 2 and the pump light source 1 are set at a certain angle to couple the pump light emitted by the pump light source 1 into the reflection cavity 3; the reflection cavity 3 is used to couple the pump light reflected by the first plane mirror 2 into the disk laser medium 4, and is also used to reflect the pump light emitted after being absorbed by the disk laser medium 4 back to the disk laser medium 4 through the reflection cavity side wall 31. After the disk laser medium 4 absorbs the pump light again, the pump light is emitted into the reflection cavity 3, and the pump light is reflected to the disk laser medium 4 through the reflection of the reflection cavity side wall 31, so that the disk laser medium 4 absorbs the pump light in multiple passes, effectively increasing the overall gain of the laser medium and achieving a higher amplification effect.

[0059] The material of the reflection cavity side wall 31 can be a high reflectivity material such as metal or ceramic, which is used to reflect the pump light; a pump light through hole 6 is provided on the reflection cavity cover 32, and a quartz lens is arranged at the through hole 6. The quartz lens is coated with a pump light transmission film to increase the transmittance of the pump light. After the pump light is reflected by the first plane mirror 2, it enters the reflection cavity 3 through the pump light through hole 6; the non-through hole area on the reflection cavity cover 32 is coated with a pump light reflection film, and the pump light emitted after being absorbed by the disk laser medium 4 is reflected back to the disk laser medium 4 through the reflection cavity side wall 31 and / or the reflection cavity cover 32. The non-through hole area on the reflection cavity cover 32 is also coated with a laser transmission film, and the quartz lens is also coated with a laser transmission film; the cooling heat sink 7 serves as the bottom of the reflection cavity 3 and is used to cool the disk laser medium 4. The pump light entering the reflection cavity 3 is incident on the disk laser medium 4. The second large surface of the disk laser medium 4 is provided with a pump light transmission film to increase the transmittance of the pump light; the first large surface is plated with a pump light reflection film and a laser reflection film. Among them, the first large surface is the large surface away from the output mirror 5, and the second large surface is the large surface close to the output mirror 5. The distance and proximity in the present invention both refer to the distance and proximity on the optical path.

[0060] In this embodiment, the wavelength of the pump light is 940nm, and the quartz lens and the second largest surface of the disk laser medium 4 are coated with a transmission film with a transmittance of 99.8% for 940nm pump light; the first plane mirror 2, the first large surface of the disk laser medium 4 and the non-through hole area on the reflection cavity cover 32 are coated with a reflection film with a reflectivity of 99.9% for 940nm pump light; the wavelength of the emitted laser is 1030nm, and the non-through hole area on the reflection cavity cover 32, the quartz lens and the first plane mirror 2 are coated with a transmission film with a transmittance of 99.9% for 1030nm laser; the first large surface of the disk laser medium 4 is coated with a reflection film with a reflectivity of 99.9% for 1030nm laser.

[0061] The pump light in the reflection cavity 3 is incident through the second large surface of the disk laser medium 4. After being absorbed, the pump light reaches the first large surface of the disk laser medium 4. After being reflected by the first large surface, the pump light is absorbed again. After being emitted through the second large surface of the disk laser medium 4, it is reflected back to the second large surface of the disk laser medium 4 by the reflection cavity side wall 31 or the reflection cavity cover 32, and is incident again through the second large surface of the disk laser medium 4 and absorbed. This multi-pass absorption is repeated many times until the pump light is almost completely absorbed. In this way, the pump light is reflected by the inner wall of the reflection cavity so that it passes through the disk laser medium many times, and the pump light is absorbed in multiple passes.

[0062] Figure 2FIG. 1 is a schematic diagram of the optical path of the pump light in the reflective cavity of the disk laser device in this embodiment. The pump light enters the reflective cavity 3 through the through hole 6, enters the disk laser medium 4 from the second largest surface of the disk laser medium 4, is refracted, and is exponentially absorbed by the second largest surface of the disk laser medium 4 (see FIG. 1 ). Figure 2 After the pump light reaches the first large surface of the disk laser medium 4, it is reflected back to the second large surface of the disk laser medium 4 (see Figure 2 ②), after being exponentially absorbed again, the pump light is refracted to the side wall 31 of the reflection cavity or the cover 32 of the reflection cavity, and the pump light is reflected by the side wall 31 of the reflection cavity or the cover 32 of the reflection cavity to be injected into the second large surface of the disk laser medium 4 again, and the pump light is exponentially absorbed again by the second large surface (see Figure 2 ③) and then projected to the first large surface of the disk laser medium 4. After the pump light reaches the first large surface of the disk laser medium 4, it is reflected back to the second large surface of the disk laser medium 4 (see Figure 2 ④), the second largest surface of the disk laser medium 4 is index-absorbed and then refracted to the side wall 31 of the reflection cavity or the cover 32 of the reflection cavity, and then reflected back to the second largest surface of the disk laser medium 4 by the side wall 31 of the reflection cavity or the cover 32 of the reflection cavity (see Figure 2 ⑤), and the cycle repeats until the pump light is completely absorbed, thereby achieving multi-pass absorption of the pump light in the disk laser medium 4.

[0063] After the pump light is completely absorbed, it excites the gain medium and emits laser light. The non-through hole area of ​​the reflective cavity cover 32 and the quartz lens are coated with a laser transmissive film, and the first plane mirror 2 is also coated with a laser transmissive film. The first large surface of the disc laser medium 4 is coated with a laser reflective film, which forms a resonant cavity with the output mirror 5. The laser oscillates and feedbacks in the resonant cavity to be amplified. Finally, the laser passes through the reflective cavity cover 32 and the first plane mirror 2 and is output through the output mirror 5.

[0064] In this embodiment, the pump light is reflected into the reflection cavity 3 by the first plane mirror 2, and the pump light is reflected by the reflection cavity side wall 31 or the reflection cavity cover 32, so as to realize multi-pass pumping of the pump light in the disk laser medium 4, effectively increase the overall gain of the disk laser medium 4, and achieve higher laser efficiency.

[0065] In a second specific embodiment, Figure 3 Schematic diagram of the structure of the disk laser device of the second embodiment. The laser device provided by the second embodiment is different from the first embodiment in that a coupling focusing lens is provided in the present embodiment, and the second plane mirror is placed inside the reflection cavity. The laser device in the present embodiment includes a pump light source 1, a second plane mirror 21, a reflection cavity 3, a disk laser medium 4, an output mirror 5, a cooling heat sink 7, a laser transmission area 8, and a coupling focusing lens 9. In the present embodiment, only the differences from the first embodiment are discussed, and the similarities are not discussed again.

[0066] The second plane mirror 21 is arranged inside the reflection cavity 3, and the second plane mirror 21 has a certain inclination angle. In the present embodiment, the second plane mirror 21 is plated with a pump light transmission film and a laser reflection film; the coupling focusing lens 9 is arranged between the reflection cavity 3 and the pump light source 1, and is used to couple the pump light into the reflection cavity 3; a laser transmission area 8 is arranged on the side wall 31 of the reflection cavity, and the laser transmission area 8 can be changed according to the position and inclination angle of the second plane mirror 21.

[0067] The pump light source 1 of the laser device is used to emit pump light. The pump light emitted by the pump light source 1 is coupled into the reflection cavity 3 through the pump light through hole 6 through the coupling focusing lens 9; the pump light entering the reflection cavity 3 is projected onto the disk laser medium 4, and the disk laser medium realizes multi-path absorption of the pump light through the disk laser medium 4, the reflection cavity side wall 31 and the reflection cavity cover 32, until the pump light is almost completely absorbed and then excites the gain medium to generate laser; the laser transmission area 8 is plated with a laser transmission film, and the laser oscillates and feedbacks in the resonant cavity to amplify, and the amplified laser is reflected to the laser transmission area 8 through the second plane mirror 21, and is transmitted to the output mirror 5 through the laser transmission area 8 and then output.

[0068] In this embodiment, the wavelength of the pump light is 940nm, and the second plane mirror 21 is coated with a transmission film with a transmittance of 99.8% for the 940nm pump light; the wavelength of the emitted laser is 1030nm, and the second plane mirror 21 is coated with a reflection film with a reflectivity of 99.8% for the 1030nm laser; the laser transmission area 8 of the side wall 31 of the reflection cavity through which the laser passes is coated with a transmission film with a transmittance of 99.9% for the 1030nm laser.

[0069] In a third specific embodiment, Figure 4 Schematic diagram of a disk laser device of the third embodiment. The laser device provided by the third embodiment is different from the first embodiment in that the reflective cavity cover 32 of this embodiment includes a first through hole and a plurality of second through holes surrounding the first through hole. The first through hole is used to transmit laser light, and the second through hole is used to transmit pump light. The first through hole is a through hole for emitting laser light, and the second through hole is a through hole for incident pump light. The laser device in this embodiment includes a pump light source 1, a reflective cavity 3, a disk laser medium 4, a cooling heat sink 7, and an output mirror 5. In this embodiment, only the differences from the first embodiment are discussed, and the similarities are not discussed again.

[0070] N through holes 10 for incident pump light are arranged on the reflective cavity cover 32, and the N through holes 10 are in an annular shape. A quartz lens is arranged at the through hole 10, and the middle part of the annularly surrounded pump light incident through hole 10 is a through hole for emitting laser light. In this embodiment, the pump light source 1, the through hole 10 and the disk laser medium 4 are arranged on the same optical path, and the pump light is incident on the disk laser medium 4 inside the reflective cavity 3 through the through hole 10, and the multi-path absorption of the pump light is realized through the disk laser medium 4, the reflective cavity side wall 31 and the reflective cavity cover 32, until the pump light is completely absorbed and then excites the gain medium to generate laser light, and the laser light oscillates and feedbacks in the resonant cavity to amplify, and finally the laser light is output through the through hole for laser emission through the output mirror 5. Figure 4 The position of the through hole 10 for incident pump light is only used as an illustration, and may also be the position of any through hole for incident pump light on the annular structure.

[0071] In this example, the wavelength of the pump light is 940nm, and the N quartz lenses are all coated with a transmission film with a transmittance of 99.8% for the 940nm pump light; the wavelength of the output laser is 1030nm, and the through-hole area where the laser is emitted is coated with a transmission film with a transmittance of 99.9% for the 1030nm laser.

[0072] Figure 5 The schematic diagram of N incident pump light through holes and the outgoing laser through hole is shown in FIG. The design of the incident pump light through hole arranged in a ring shape helps to ensure that each area of ​​the disk laser medium 4 is irradiated with relatively uniform pump light. The uniform pump light distribution can reduce the thermal effect caused by uneven pump light intensity in the laser medium, thereby reducing the wavefront distortion caused by the thermal effect.

[0073] Figure 6 Schematic diagram of the structure of a laser amplifier of the fourth embodiment, the laser amplifier comprises a pump light source 1, a seed laser source 11, a first plane mirror 2, a reflection cavity 3 and a disk laser medium 4, wherein the disk laser medium is arranged inside the reflection cavity, and the first plane mirror 2 is arranged outside the reflection cavity. Figure 6 No output mirror is provided, and no resonant cavity is formed. The reflective cavity 3 includes a reflective cavity side wall 31 and a reflective cavity cover 32, wherein the reflective cavity side wall 31 is plated with a reflective material for reflecting the pump light, and a first through hole 61 and a second through hole 62 are provided on the reflective cavity side wall 31; a through hole 6 for incident pump light is provided on the reflective cavity cover 32, and a pump light reflective film and a seed laser reflective film are plated in the non-through hole part of the reflective cavity cover 32; a cooling heat sink 7 is used as the bottom of the reflective cavity 3 to cool the disk laser medium 4 fixed on the cooling heat sink 7.

[0074] The pump light provided by the pump light source 1 is reflected by the first plane mirror 2 and then incident on the disk laser medium 4 inside the reflective cavity 3. The pump light is absorbed by the disk laser medium 4 and then emitted to the reflective cavity side wall 31 or the reflective cavity cover 32. The pump light is reflected by the reflective cavity side wall 31 or the reflective cavity cover 32 and then incident on the disk laser medium 4 again. This cycle is repeated, and the pump light is completely absorbed by the disk laser medium 4. The energy of the pump light is used to excite the atoms or ions in the disk laser medium 4, so that they reach an excited state, thereby storing energy and generating gain. The seed laser source 11 provides a seed laser, and the seed laser is incident on the disk laser medium 4 inside the reflective cavity 3 that has been excited by the pump light through the first through hole 61 on the reflective cavity side wall 31; at this time, the excited atoms or ions in the disk laser medium 4 can release additional photons, thereby amplifying the intensity of the seed laser, and the amplified seed laser is output through the second through hole 62 on the reflective cavity side wall 31. When the seed laser passes through the disk laser medium 4, the photons interact with the excited atoms, providing gain through the disk laser medium 4, resulting in an increase in the intensity of the seed laser. The first through hole 61 is a through hole for incident seed laser, and the second through hole 62 is a through hole for emitting the seed laser after energy amplification.

[0075] Figure 7 This is a schematic diagram of a laser amplifier of the fifth embodiment, which includes a pump light source 1, a hollow seed laser source 12, a second plane mirror 21, a reflection cavity 3, a disk laser medium 4 and a coupled focusing lens, wherein the disk laser medium 4 is arranged inside the reflection cavity 3, and the second plane mirror 21 is arranged between the reflection cavity 3 and the pump light source 1.

[0076] The second plane mirror 21 is plated with a pump light transmission film and a hollow seed laser reflection film; the reflection cavity 3 includes a reflection cavity side wall 31 and a reflection cavity cover 32. The reflection cavity side wall 31 is plated with a reflection material for reflecting the pump light, and a third through hole 63 is arranged on the reflection cavity side wall 31; a fourth through hole 64 is arranged on the reflection cavity cover 32, and a quartz lens is arranged at the fourth through hole 64, and the quartz lens is plated with a pump light transmission film and a hollow seed laser transmission film, and the non-through hole area of ​​the reflection cavity cover 32 is plated with a hollow seed laser transmission film; the cooling heat sink 7 serves as the bottom of the reflection cavity 3, and is used to cool the disk laser medium 4 fixed on the cooling heat sink 7.

[0077] In this embodiment, the pump light provided by the pump light source 1 is focused by the coupling focusing lens 9, and the focused pump light is emitted onto the disk laser medium 4 in the reflection cavity 3 through the second plane mirror 21. After being absorbed by the disk laser medium 4, the pump light is emitted onto the reflection cavity side wall 31 or the reflection cavity cover 32, and is reflected by the reflection cavity side wall 31 or the reflection cavity cover 32 and then emitted into the disk laser medium 4 again. This cycle is repeated to achieve multi-pass absorption of the pump light. The pump light is completely absorbed by the disk laser medium 4, and the energy of the pump light is used to excite the atoms or ions in the disk laser medium 4 to make them reach an excited state, thereby storing energy and generating gain. The hollow seed laser provided by the hollow seed laser source 12 is incident from the third through hole 63 on the side wall 31 of the reflective cavity into the disk laser medium 4 that has been excited by the pump light inside the reflective cavity 3 (the hollow seed laser can also be incident from other positions into the reflective cavity, and this embodiment is only taken as an example). The excited atoms or ions in the disk laser medium 4 can release additional photons, thereby amplifying the intensity of the hollow seed laser. The amplified hollow seed laser is transmitted to the second plane mirror 21 through the reflective cavity cover 32 and the fourth through hole, and is reflected and output by the second plane mirror 21. Among them, the third through hole 63 is a through hole for the hollow seed laser to be incident, and the fourth through hole 64 is a through hole for the incident pump light and the hollow seed laser after the outgoing energy is amplified.

[0078] In this example, the wavelength of the pump light is 940nm, and the second plane mirror 2 is coated with a transmission film with a transmittance of 99.8% for the 940nm pump light; the wavelength of the emitted hollow seed laser is 1030nm, and the second plane mirror 2 is coated with a reflection film with a reflectivity of 99.9% for the 1030nm laser.

[0079] For this embodiment, the formed laser is a hollow laser, which is generally used in an amplifier. The seed laser used is a hollow seed laser. The structure of the hollow laser can reduce the light intensity at the center of the beam, thereby reducing the thermal effect and optical nonlinear effect in the central area, which may help to improve the quality and stability of the beam. During the amplification process, the improvement in beam quality can make the final output laser more uniform, with better directivity and smaller spot size. The propagation of the hollow laser in the gain medium can improve the interaction efficiency between the beam and the medium. Because there is almost no light intensity in the central area of ​​the beam, the peripheral part of the beam can interact with the gain medium more effectively during the amplification process, thereby improving the amplification efficiency.

[0080] The present invention utilizes the side wall of the reflective cavity to reflect the pump light so that the pump light passes through the disk laser medium for multiple times, performs multi-pass absorption on the pump light, increases the effective absorption length of the disk laser medium, realizes uniform pumping, improves laser efficiency, effectively increases the overall gain of the laser medium, and achieves a higher amplification effect. The laser device of the present invention has a simple structure and is easy to use.

[0081] In the description of the present invention, it should be noted that the terms "upper", "lower", etc. 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 present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the 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 the specific circumstances.

[0082] It should also be noted that, in the description of the present invention, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0083] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. An intracavity scattering multi-pass pumped disk laser device, characterized in that: The device comprises a pump light source, a reflection cavity, a disk laser medium and an output mirror, wherein the disk laser medium is arranged inside the reflection cavity. The pump light source is used to provide pump light; The reflection cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium generates laser after multi-pass absorption of the pump light; The first large surface of the disk laser medium away from the output mirror and the output mirror form a resonant cavity, and the resonant cavity is used for reflecting oscillating and amplifying laser light; The output mirror is used to output laser light.

2. The laser device according to claim 1, characterized in that The reflection cavity comprises a reflection cavity side wall, a reflection cavity cover and a cooling module. The reflection cavity side wall is plated with a pump light reflecting material. The cooling module serves as the bottom of the reflection cavity and is used to cool the disk laser medium fixed on the cooling module.

3. The laser device according to claim 2, characterized in that: The reflective cavity cover is provided with a through hole for incident pump light, a quartz lens is provided at the through hole, and the quartz lens is plated with a pump light transmission film.

4. The laser device according to claim 3, characterized in that The non-through hole area of ​​the reflective cavity cover is plated with a laser transmission film and a pump light reflection film.

5. The laser device according to claim 1, characterized in that The first large surface of the disk laser medium is coated with a pump light reflection film and a laser reflection film, and the second large surface opposite to the first large surface is coated with a pump light transmission film.

6. The laser device according to claim 1, characterized in that The device also includes a first plane mirror, which is arranged between the reflection cavity and the output mirror, and is coated with a pump light reflection film and a laser transmission film. The first plane mirror is used to reflect the pump light emitted by the pump light source into the reflection cavity and transmit the laser to the output mirror.

7. The laser device according to claim 1, characterized in that: The device also includes a second plane mirror arranged inside the reflection cavity, The second plane mirror is plated with a pump light transmission film and a laser reflection film, and a laser transmission area is arranged on the side wall of the reflection cavity for transmitting the output laser to the output mirror.

8. The laser device according to claim 1, characterized in that The reflective cavity cover of the reflective cavity comprises a first through hole and a plurality of second through holes surrounding the first through hole, the first through hole is used to transmit laser light, and the second through holes are used to transmit pump light.

9. An intracavity scattering multi-pass pumped laser amplifier, characterized in that: The laser amplifier comprises a pump light source, a seed laser source, a reflection cavity and a disk laser medium, wherein the disk laser medium is arranged inside the reflection cavity. The pump light source is used to provide pump light; The seed laser source is used to provide seed laser; The reflective cavity comprises a reflective cavity side wall and a reflective cavity cover, wherein the reflective cavity side wall is provided with a first through hole and a second through hole, and the reflective cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium absorbs the pump light in multiple passes and then amplifies the energy of the seed laser entering the reflective cavity through the first through hole; The second through hole is used to output the seed laser after energy amplification.

10. An intracavity scattering multi-pass pumped laser amplifier, characterized in that: The laser amplifier comprises a pump light source, a hollow seed laser source, a reflection cavity and a disk laser medium, wherein the disk laser medium is arranged inside the reflection cavity. The pump light source is used to provide pump light; The hollow seed laser source is used to provide hollow seed laser; The reflection cavity comprises a reflection cavity side wall and a reflection cavity cover, wherein the reflection cavity side wall is provided with a third through hole, and the reflection cavity is used to reflect the pump light emitted after being absorbed by the disk laser medium back to the disk laser medium, so that the disk laser medium absorbs the pump light in multiple passes and then amplifies the energy of the hollow seed laser entering the reflection cavity through the third through hole; The reflective cavity cover is provided with a fourth through hole, and the fourth through hole is used to output the amplified hollow seed laser.

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