A compact high repetition rate disc regeneration amplifier

Abstract

The invention relates to the field of laser technology, and provides a compact high-repetition-rate disk regenerative amplifier, comprising: an input-output optical path, configured to input seed light and output amplified laser, the input-output optical path comprising: a seed light source, a beam conversion lens group, an optical isolator, a first 1 / 2 wave plate, a first polarization beam splitter, a Faraday rotator and a second 1 / 2 wave plate; a regenerative amplifier optical path, configured to amplify the input seed light, the regenerative amplifier optical path comprising: a pump module and a disk regenerative amplifier cavity, the disk regenerative amplifier cavity comprising: a second polarization beam splitter, a Pockels cell, a 1 / 4 wave plate, a first plane reflector, a first concave reflector, a spherical reflector, a second plane reflector and a disk module; the invention shortens the resonant cavity length of the disk regenerative amplifier, and solves the technical problem that the minimum light spot is located in the resonant cavity due to the long resonant cavity length, thereby damaging the device in the resonant cavity.

Description

Technical Field

[0001] The present application relates to the field of laser technology, and in particular to a compact high-repetition-rate disc regeneration amplifier. Background Art

[0002] Since its advent, laser technology has been continuously developing, and solid-state lasers have been widely used in basic scientific research, industrial processing, people's livelihood and medical fields. Traditional solid-state lasers have serious thermal effects that limit the further improvement of output laser quality, limiting their application scenarios and development. In order to further improve the thermal management capabilities of solid-state lasers, slab lasers, fiber lasers and disk lasers have been developed from traditional rod lasers. Compared with slab lasers and fiber lasers, disk lasers have the advantages of high peak power, high energy and high beam quality.

[0003] Disk lasers make the gain medium into a large and thin disk shape, which fundamentally solves the problem of thermal effects in solid-state lasers. In the development of ultrafast lasers, thanks to the invention of chirped pulse amplification technology, the peak power of lasers has been significantly improved. Chirped pulse amplification systems usually use a combination of a large prevention unit and a main amplification unit to amplify the energy of the seed light. The regenerative amplifier based on disk technology is often used as a pre-amplification unit in the chirped pulse amplification system because it can achieve high-energy pulse output while maintaining good beam quality. It can amplify the seed light with energy of microjoules or nanojoules to hundreds of millijules. Summary of the invention

[0004] Some embodiments of the present application provide a compact high repetition rate disc regeneration amplifier, comprising:

[0005] An input and output optical path is configured to input seed light and output amplified laser light, the input and output optical path comprising: a seed light source, a beam conversion lens group, an optical isolator, a first 1 / 2 wave plate, a first polarization beam splitter, a Faraday rotator and a second 1 / 2 wave plate;

[0006] A regenerative amplifier optical path is configured to amplify the input seed light, the regenerative amplifier optical path comprises: a pump module and a disk regenerative amplifier cavity, wherein the disk regenerative amplifier cavity comprises: a second polarization beam splitter, a Pockels cell, a quarter wave plate, a first plane reflector, a first concave reflector, a spherical reflector, a second plane reflector and a disk module;

[0007] The seed light source outputs s-polarized seed light, and the seed light is transformed by a beam transformation lens group so that the light spot entering the disc regenerative amplifier cavity matches the characteristics of the disc regenerative amplifier cavity; the s-polarized seed light after the beam transformation passes through the optical isolator and the first 1 / 2 wave plate to become p-polarized seed light, and the p-polarized seed light passes through the first polarization beam splitter, the Faraday rotator and the second 1 / 2 wave plate and maintains the p-polarization state to enter the regenerative amplifier optical path;

[0008] The seed light entering the optical path of the regenerative amplifier passes through a Pockels cell, a quarter wave plate, a first plane reflector, and a first concave reflector. After being reflected by the first concave reflector, the seed light returns to the original path and passes through the first plane reflector, the quarter wave plate, the Pockels cell, the second polarization beam splitter, the spherical reflector, and the second plane reflector in sequence before reaching the disc module. After being amplified by the disc module, the seed light returns along the original path and is amplified back and forth in the resonant cavity. The round-trip time of the seed light in the resonant cavity is controlled by controlling the working state and working time of the Pockels cell. After the energy of the seed light is amplified to the target value, it is output from the first polarization beam splitter.

[0009] In some embodiments, the cavity length of the disc regeneration amplifier cavity is 2m~2.5m.

[0010] In some embodiments, the minimum diameter of the light spot of the amplified light path in the disc regeneration amplifier cavity is located at the end surface of the disc module.

[0011] In some embodiments, the disc module includes:

[0012] A reflector circuit configured to allow the pump laser to travel back and forth multiple times in the disk module;

[0013] A disk laser crystal, serving as a laser gain medium to amplify the seed light;

[0014] The disk laser crystal serves as an intra-cavity reflection element of the disk regenerative amplifier cavity and is located on an end surface of the disk regenerative amplifier cavity.

[0015] In some embodiments, the

[0016] The pump module is used to output pump light to pump the disk laser crystal;

[0017] The laser spot size of the amplified optical path at the end face of the disk laser crystal is 0.7-0.8 times the spot size of the pump light at the end face of the disk laser crystal.

[0018] In some embodiments, the disk laser crystal includes at least one of the following: Yb:YAG, Yb:KGW, Yb:CALGO, Yb:LuScO3, Ho:YAG, Ho:KYW, Tm:YAG, Tm:KYW, Cr:ZnSe and Tm:LLF;

[0019] And / or, the diameter of the disk laser crystal is 5-50 mm; and / or, the thickness of the disk laser crystal is on the order of hundreds of microns.

[0020] In some embodiments, the seed light source is a fiber laser with an output repetition rate range of 10 Hz to 100 MHz.

[0021] In some embodiments, the first concave reflector is a 0-degree first concave reflector, the spherical reflector is a 0-degree spherical reflector, the first plane reflector is a 45-degree plane reflector; and the second plane reflector is a 0-degree plane reflector.

[0022] In some embodiments, the minimum diameter of the light spot of the amplified light path in the disc regeneration amplifier cavity is 2 mm to 2.1 mm.

[0023] In some embodiments, the disc module further includes:

[0024] A mechanical fixture for maintaining the stability of the disc module;

[0025] A cooling circuit is provided on the mechanical fixture and is used to conduct heat away from the disk laser crystal.

[0026] Compared with the related art, the above solution of the embodiment of the present application has at least the following beneficial effects:

[0027] The present invention proposes a compact high-repetition-rate disk regeneration amplifier based on the concept of a thermally nearly unstable cavity. Under the condition of ensuring that the output laser has a high beam quality, the length of the resonant cavity is less than 2.5m, which greatly shortens the length of the resonant cavity of the disk regeneration amplifier and solves the technical problem that the minimum light spot is located in the resonant cavity due to the long length of the resonant cavity, thereby damaging the devices in the resonant cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0029] Figure 1A schematic diagram of the structure of a compact high repetition rate disc regeneration amplifier provided in some embodiments of the present application;

[0030] Figure 2 A schematic diagram of the light spot sizes at different positions in the resonant cavity of a compact disk regenerative amplifier provided in some embodiments of the present application;

[0031] Figure 3 A schematic diagram of the laser spot morphology when the complex frequency is 50 kHz and the output laser power is 32.7 W provided in some embodiments of the present application.

[0032] Description of reference numerals:

[0033] Pump module 1, collimating lens 2, third plane mirror 3, second concave mirror 4, mechanical fixture 5, cooling circuit 6, heat sink 7, disk laser crystal 8, spherical mirror 9, second polarization beam splitter 10, first plane mirror 11, first concave mirror 12, second plane mirror 13, 1 / 4 wave plate 14, Pockels cell 15, seed light source 16, first lens 17, second lens 18, third lens 19, optical isolator 20, fourth plane mirror 21, first 1 / 2 wave plate 22, first polarization beam splitter 23, Faraday rotator 24, second 1 / 2 wave plate 25. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0035] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0036] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0037] It should be understood that although the terms first, second, third, etc. may be used to describe in the embodiments of the present application, these should not be limited to these terms. These terms are only used to distinguish. For example, without departing from the scope of the embodiments of the present application, the first may also be referred to as the second, and similarly, the second may also be referred to as the first.

[0038] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product 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 product or device. In the absence of more restrictions, the elements defined by the sentence "comprises a" do not exclude the presence of other identical elements in the product or device including the elements.

[0039] The disk laser crystal (hereinafter referred to as the disk) is not only used as a gain medium in the laser construction process, but also as a folding mirror or end mirror in the resonant cavity. Its front surface is coated with a high-reflection film for the output laser wavelength and the pump light wavelength, and its rear surface is coated with a high-transmittance film for the output laser wavelength and the pump light wavelength. Depending on the different surface shapes of the disk, it is usually equivalent to a plane mirror or a spherical reflector with different curvature radii in the resonant cavity design. Although the disk technology has efficient thermal management capabilities, during the operation of the laser, as the pump power increases, the surface shape of the disk will still change to a certain extent, affecting the performance of the resonant cavity.

[0040] The disk regenerative amplifier in the related technology usually adopts a stable cavity design scheme. In order to enable the disk laser to work in the stable area in the entire range, the cavity length is usually longer. For regenerative amplifiers with a single pulse energy greater than 10mJ, the cavity length is more than 5m, and some cavities can reach 15m. The problems caused by the longer cavity length of the disk regenerative amplifier are mainly the following aspects: first, the stable cavity design will cause a small light spot in some areas of the resonant cavity, which is limited by the damage threshold of the optical components and limits the increase in the output laser energy of the disk regenerative amplifier; secondly, the more optical components in the cavity increase the loss of the resonant cavity and affect the light amplification efficiency; thirdly, the laser is large in size, the system is more complex, the cost is higher and affects its stability, and the working environment requirements are high, which is not conducive to further industrial applications.

[0041] To this end, the present invention proposes a compact high-repetition-rate disc regeneration amplifier based on the concept of a thermally nearly unstable cavity. While ensuring that the output laser has a high beam quality, the length of the resonant cavity is less than 2.5m, which greatly shortens the length of the resonant cavity of the disc regeneration amplifier and solves the technical problem that the minimum light spot is located in the resonant cavity due to the long length of the resonant cavity, thereby damaging the devices in the resonant cavity.

[0042] The present application is described in detail below with reference to the accompanying drawings.

[0043] like Figure 1 As shown, the present application provides a compact high-repetition-rate disc regeneration amplifier, including: an input-output optical path and a regeneration amplifier optical path, wherein the input-output optical path is configured to input seed light and output amplified laser light, and the input-output optical path includes: a seed light source 16, a beam conversion lens group composed of a first lens 17, a second lens 18, and a third lens 19, an optical isolator 20, a first 1 / 2 wave plate 22, a first polarization beam splitter 23, a Faraday rotator 24, and a second 1 / 2 wave plate 25; the optical isolator 20 is used to protect optical components, and its function is to allow seed light to pass unidirectionally from left to right, but not from right to left. The first polarization beam splitter 23 is highly transparent to lasers in the p-polarization state and highly reflective to lasers in the s-polarization state, and the angle between the incident light and the normal of the lens is 45 degrees. The Faraday rotator 24 uses the non-reciprocal properties of magneto-optical materials to change the phase of the incident laser, and together with the 45-degree first polarization beam splitter 23 and the second 1 / 2 wave plate 25, forms an optical isolator. The seed light source 16 outputs s-polarized seed light, and the seed light is beam-transformed by the beam-transforming lens group so that the light spot entering the cavity of the disc regenerative amplifier matches the cavity characteristics of the disc regenerative amplifier; the s-polarized seed light after beam-transformation passes through the optical isolator 20 and the first 1 / 2 wave plate 22 to become p-polarized seed light, and the p-polarized seed light passes through the first polarization beam splitter 23, the Faraday rotator 24 and the second 1 / 2 wave plate 25 to enter the regenerative amplifier optical path while maintaining the p-polarized state. The optical path can also be folded by the fourth plane reflector 21 to facilitate optical path adjustment.

[0044] In some embodiments, the regenerative amplifier optical path is configured to amplify the input seed light, and the regenerative amplifier optical path includes: a pump module 1 and a disk regenerative amplifier cavity, wherein the disk regenerative amplifier cavity includes: a second polarization beam splitter 10, a Pockels cell 15, a quarter wave plate 14, a first plane reflector 11, a first concave reflector 12, a spherical reflector 9, a second plane reflector 13 and a disk module; wherein the 45-degree second polarization beam splitter 10 has the function of high transmittance of laser light in the p-polarization state and high reflection of laser light in the s-polarization state, and the angle between the incident light and the normal line of the lens is 45 degrees. The first concave reflector 12 has the function of reducing the divergence angle of the incident laser and fully reflecting the laser light incident at 0 degrees. The quarter wave plate 14 has the function of changing the phase of the seed light, converting the linear polarization light into the circular polarization light, and converting the circular polarization into the linear polarization. The Pockels cell 15 has the function of, when a voltage is applied, the Pockels cell is equivalent to a quarter wave plate, that is, the phase of the laser light changes by 45 degrees after passing through. The p-polarized seed light entering the optical path of the regenerative amplifier passes through the unvoltaged Pockels cell 15, the quarter wave plate 14, the first plane reflector 11, and the first concave reflector 12 in sequence. After being reflected by the first concave reflector 12, it returns to the original path and passes through the first plane reflector 11, the quarter wave plate 14, the unvoltaged Pockels cell 15, the second polarization beam splitter 10, the spherical reflector 9, and the second plane reflector 13 in sequence to reach the disc module. After passing through the disc module, it is amplified in the resonant cavity. The round trip time of the seed light in the resonant cavity is controlled by controlling the working state and working time of the Pockels cell 15. After the seed light energy is amplified to the target value, it is output from the first polarization beam splitter 23. Among them, the first plane reflector 11 is a total reflection of the laser incident at 45 degrees, folds the resonant cavity optical path and facilitates the optical path adjustment.

[0045] In some embodiments, the seed light source 16 can be a fiber laser, and the laser emitted by the fiber laser is the seed light to be amplified. The picosecond light generated by the fiber laser is amplified and broadened, and then frequency selected by an acousto-optic modulator, and the repetition frequency range is 10Hz~100MHz. The seed light in the s-polarization state is transformed by a lens group, so that the light spot entering the disc regeneration amplifier resonant cavity matches the cavity type characteristics of the resonant cavity. The seed light in the s-polarization state after the beam transformation passes through the optical isolator 20, the 45-degree fourth plane reflector 21, and the first 1 / 2 wave plate 22 to become the p-polarization state. The seed light in the p-polarization state passes through the first polarization beam splitter 23 and the Faraday rotator 24 and the second 1 / 2 wave plate 25 to maintain the p-polarization state, and then is coupled into the resonant cavity of the disc regeneration amplifier through the second polarization beam splitter 10. The p-polarized seed light entering the resonant cavity of the disk regenerative amplifier passes through the unvoltaged Pockels cell 15, the quarter wave plate 14, the 45-degree first plane reflector 11, and the first concave reflector 12 in sequence. After being reflected by the first concave reflector 12, it returns to the original path and passes through the 45-degree first plane reflector 11 and the quarter wave plate 14 in sequence, and then changes to the s-polarized state. The s-polarized seed light passes through the unvoltaged Pockels cell 15, is reflected by the second polarization beam splitter 10, and then passes through the spherical reflector 9 and the second plane reflector 13 in sequence to reach the gain medium disk laser crystal 8 in the cavity. The seed light energy is amplified and is amplified by the disk laser crystal 8. After reflection, the seed light returns to the second polarization beam splitter 10 along the original path, passes through the second plane reflector 13, the spherical reflector 9, the second polarization beam splitter 10, the Pockels cell 15 kept in working state by applying a quarter-wave voltage, the 1 / 4 wave plate 14, the 45-degree first plane reflector 11, and the first concave reflector 12 in sequence. During this process, the seed light in the s-polarization state passes through the 1 / 4 wave plate 14 and the Pockels cell 15 kept in working state by applying a quarter-wave voltage twice, and the polarization state remains unchanged. Therefore, after being reflected by the second polarization beam splitter 10, it oscillates back and forth in the resonant cavity, and passes through the disk laser crystal 8 for multiple times to obtain gain for energy amplification. When the energy of the seed light is amplified to the target value, the quarter-wave voltage applied to the Pockels cell 15 is canceled to keep it in an inoperative state. The s-polarized seed light amplified in the cavity passes through the 1 / 4 wave plate 14 and the unpowered Pockels cell 15 twice and becomes a p-polarized state. The p-polarized amplified light is coupled out through the second polarization beam splitter 10, and then passes through the second 1 / 2 wave plate 25 and the Faraday rotator 24 and becomes an s-polarized state, and is reflected and output after passing through the first polarization beam splitter 23.

[0046] The Pockels cell 15 is controlled by the electric pulse generated by the digital delay signal generator to control its operation or not. By controlling the delay and width of the electric pulse, the output of the seed light and the number of round trips in the cavity are controlled together with the second polarization beam splitter 10. The disk laser crystal 8 includes at least one of the following: Yb:YAG, Yb:KGW, Yb:CALGO, Yb:LuScO3, Ho:YAG, Ho:KYW, Tm:YAG, Tm:KYW, Cr:ZnSe and Tm:LLF; the diameter of the disk laser crystal 8 is 5-50mm, for example, it is a Yb:YAG disk laser crystal, with a thickness of hundreds of microns, a diameter of 5~50mm, and a doping concentration of 0.3~10%. The front surface of the disk is coated with an anti-reflection film for the pump light wavelength and the seed light wavelength, and the rear surface is coated with a high reflection film for the pump light wavelength and the seed light wavelength.

[0047] In some embodiments, the first concave reflector is a 0-degree first concave reflector, the spherical reflector is a 0-degree spherical reflector, the first plane reflector 11, the third plane reflector 3, and the fourth plane reflector 21 are 45-degree plane reflectors; the second plane reflector 13 is a 0-degree plane reflector. Among them, the 0-degree reflector is also called a small-angle reflector, which is used to reflect all incident light within a certain angle range, such as total reflection of incident laser light within a range of 0 degrees to 4 degrees.

[0048] In some embodiments, the disk module includes: a reflector loop configured to make the pump laser travel back and forth multiple times in the disk module; optionally, the reflector loop is composed of two third plane reflectors 3 and two second concave reflectors 4 to form a compact pump light reflection loop. A disk laser crystal 8, as a laser gain medium, provides gain for the seed light; wherein the disk laser crystal 8 is located at the end face of the disk regenerative amplifier cavity as an intracavity reflection element of the disk regenerative amplifier cavity.

[0049] In some embodiments, the disc module further includes: a mechanical fixture 5 for maintaining a stable mechanical structure of the disc module and having good thermal conductivity; a cooling circuit 6 in which a cooling liquid, such as deionized water, is circulated, and the cooling circuit 6 is arranged inside the mechanical fixture 5 to conduct heat of the disc laser crystal 8 through the circulation of the cooling liquid. The disc laser crystal 8 is located on a heat sink 7, which is usually made of diamond or copper tungsten to quickly conduct waste heat from the disc laser crystal 8.

[0050] In some embodiments, the pump module 1 is, for example, a semiconductor laser, and outputs pump light with a laser center wavelength of 969 nm or 940 nm. The pump light output by the pump module 1 pumps the disk laser crystal 8; the pump light oscillates back and forth between the disk laser crystal 8 and the reflector circuit. In order to make the output laser of the disk regenerative amplifier have good beam quality, the laser spot size at the disk needs to meet certain mode matching requirements with the pump spot size, that is, the laser spot size should be 0.7 to 0.8 times the pump spot size to achieve laser output in the fundamental transverse mode. The pump module 1 collimates the pump light through the collimating lens 2 and inputs it into the disk module.

[0051] In some embodiments, Figure 2 As shown, the minimum diameter of the light spot of the amplified light path in the disc regeneration amplifier cavity is located at the end face of the disc laser crystal 8. The minimum diameter of the light spot of the amplified light path in the disc regeneration amplifier cavity is 2mm~2.1mm. At any position away from the disc laser crystal 8, the diameter of the light spot of the amplified light path in the disc regeneration amplifier cavity is larger than the diameter of the light spot at the end face of the disc laser crystal 8. The cavity length of the disc regeneration amplifier cavity is 2m~2.5m. Figure 3 As shown, when the repetition frequency is 50kHz and the output laser power is 32.7W, the laser spot shape has a minimum spot size of 2mm. The cavity length of the disk regenerative amplifier cavity refers to the geometric distance from the disk laser crystal 8 to the second plane reflector 13, plus the geometric distance from the second plane reflector 13 to the spherical reflector 9, plus the geometric distance from the spherical reflector 9 to the second polarization beam splitter 10, plus the geometric distance from the second polarization beam splitter 10 to the first plane reflector 11, plus the geometric distance from the first plane reflector 11 to the first concave reflector 12.

[0052] The smallest spot in the cavity of the disk regenerative amplifier proposed by the present invention is at the position of the disk, so that there is no tiny spot in the resonant cavity of the disk regenerative amplifier proposed by the present invention that is easy to damage the optical element. In order to make the output laser of the disk regenerative amplifier have good beam quality, the laser spot size at the disk needs to meet certain mode matching requirements with the pump spot size, that is, the laser spot size should be 0.7~0.8 times the pump spot size, so there will be no tiny spot in the resonant cavity, and the amplification of the seed light energy is not limited by the damage threshold of the optical element in the cavity, so that the overall laser amplification power can be improved. In addition, the resonant cavity length is short, which is less than 2.5m in this embodiment, for example, 2m, so the system is simpler and easier to debug, and more stable than the long cavity. The disk regenerative amplifier cavity used in the embodiment of the present application has fewer optical elements and less loss in the cavity, which can further improve the efficiency of light amplification. In addition, the disk regenerative amplifier requires less space and fewer components, which can save costs and better meet the development needs of industrialization.

[0053] Finally, it should be noted that: each embodiment in this specification is described by way of example, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referred to each other. For the system or device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0054] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A compact high repetition rate disc regeneration amplifier, characterized in that ,include: An input and output optical path is configured to input seed light and output amplified laser light, the input and output optical path comprising: a seed light source, a beam conversion lens group, an optical isolator, a first 1 / 2 wave plate, a first polarization beam splitter, a Faraday rotator and a second 1 / 2 wave plate; A regenerative amplifier optical path is configured to amplify the input seed light, the regenerative amplifier optical path comprises: a pump module and a disk regenerative amplifier cavity, wherein the disk regenerative amplifier cavity comprises: a second polarization beam splitter, a Pockels cell, a quarter wave plate, a first plane reflector, a first concave reflector, a spherical reflector, a second plane reflector and a disk module; The disk module comprises: a reflector circuit configured to make the pump laser travel back and forth multiple times in the disk module; a disk laser crystal, used as a laser gain medium to amplify the seed light; wherein the disk laser crystal is used as an intracavity reflection element of the disk regenerative amplifier cavity and is located at the end face of the disk regenerative amplifier cavity; the pump module is used to output pump light to pump the disk laser crystal; The seed light source outputs s-polarized seed light, and the seed light is transformed by a beam transformation lens group so that the light spot entering the disc regenerative amplifier cavity matches the characteristics of the disc regenerative amplifier cavity; the s-polarized seed light after the beam transformation passes through the optical isolator and the first 1 / 2 wave plate to become p-polarized seed light, and the p-polarized seed light passes through the first polarization beam splitter, the Faraday rotator and the second 1 / 2 wave plate and maintains the p-polarization state to enter the regenerative amplifier optical path; The seed light entering the optical path of the regenerative amplifier passes through a Pockels cell, a quarter wave plate, a first plane reflector, and a first concave reflector. After being reflected by the first concave reflector, the seed light returns to the original path and passes through the first plane reflector, the quarter wave plate, the Pockels cell, the second polarization beam splitter, the spherical reflector, and the second plane reflector in sequence before reaching the disc module. After being amplified by the disc module, the seed light returns along the original path and is amplified back and forth in the resonant cavity. The round-trip time of the seed light in the resonant cavity is controlled by controlling the working state and working time of the Pockels cell. After the energy of the seed light is amplified to the target value, it is output from the first polarization beam splitter.

2. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that ,The cavity length of the disc regeneration amplifier cavity is 2m~2.5m.

3. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that The minimum diameter of the light spot of the amplified light path in the disc regeneration amplifier cavity is located at the end surface of the disc module.

4. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that , The laser spot size of the amplified optical path at the end face of the disk laser crystal is 0.7-0.8 times the spot size of the pump light at the end face of the disk laser crystal.

5. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that , the disk laser crystal includes at least one of the following: Yb:YAG, Yb:KGW, Yb:CALGO, Yb:LuScO3, Ho:YAG, Ho:KYW, Tm:YAG, Tm:KYW, Cr:ZnSe and Tm:LLF; And / or, the diameter of the disk laser crystal is 5-50 mm; and / or, the thickness of the disk laser crystal is on the order of hundreds of microns.

6. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that , the seed light source is a fiber laser with an output repetition rate range of 10Hz~100MHz.

7. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that , the first concave reflector is a 0-degree first concave reflector, the spherical reflector is a 0-degree spherical reflector, the first plane reflector is a 45-degree plane reflector; and the second plane reflector is a 0-degree plane reflector.

8. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that , the minimum diameter of the light spot of the amplified light path in the disc regeneration amplifier cavity is 2mm~2.1mm.

9. The compact high repetition rate disc regeneration amplifier according to claim 1, characterized in that , the disc module also includes: A mechanical fixture for maintaining the stability of the disc module; A cooling circuit is provided on the mechanical fixture and is used to conduct heat away from the disk laser crystal.

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