Optical path four-time multiplexed disc laser multi-pass amplifier
By using a disk laser multi-pass amplifier with a four-fold optical path multiplexing, the complex optical path problem in the prior art is solved by using a mirror assembly and a disk crystal to form a four-fold multiplexed optical path, thus reducing the amplifier size and simplifying the optical path.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI
- Filing Date
- 2026-03-09
- Publication Date
- 2026-06-02
AI Technical Summary
Existing disk laser multi-pass amplifiers have low single-pass gain and require multiple passes through the gain crystal, resulting in complex optical paths and large structures, and making the arrangement of optical components inflexible.
A disk laser multi-pass amplifier with four-fold optical path multiplexing is adopted. The four-fold multiplexed optical path is formed by the combination of the reflector assembly and the disk crystal, so that the seed laser passes through the disk crystal four times, simplifying the optical path structure.
At the same amplification level, the optical path is simplified to 1/4, significantly reducing the amplifier size and improving the flexibility and compactness of the optical path.
Smart Images
Figure CN121813099B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of laser amplifiers, and more specifically, to a four-way multiplexed optical disk laser multipass amplifier. Background Technology
[0002] A disk laser multipass amplifier is a type of solid-state laser amplifier, mainly consisting of a disk-shaped gain crystal, a pump source, optical lenses, and a seed laser. The pump light generated by the pump source is injected into the disk-shaped gain crystal, causing population inversion of electrons within the crystal, placing them in an "energy storage" state. The optical lenses guide the seed laser through the disk-shaped gain crystal multiple times, continuously extracting pump energy and amplifying the seed light's power to achieve high-power or high-energy laser output.
[0003] Existing disk laser multipass amplifiers have relatively low single-pass gain, meaning the seed light gains little after passing through the gain crystal only once. Multiple passes through the gain crystal are required to effectively extract pump energy, necessitating corresponding reflection optical paths. The more passes, the more complex the optical path becomes. This results in a larger amplifier structure and less flexibility in arranging optical components. Summary of the Invention
[0004] The purpose of this application is to provide a four-way multiplexed optical disk laser multipass amplifier, which can solve at least one of the technical problems mentioned above. The specific solution is as follows:
[0005] According to a specific embodiment of this application, this application proposes an optical path quadruple multiplexing disk laser multipass amplifier, comprising:
[0006] Disc crystals are used to achieve laser amplification;
[0007] A seed light source is used to provide a seed laser with a first polarization state to be amplified;
[0008] The first conversion component is configured to not change the polarization state of the laser passing through the first conversion component along the first direction, but to change the polarization state of the laser passing through the first conversion component along the opposite second direction;
[0009] The second conversion component is used to change the polarization state of the laser light passing through the second conversion component;
[0010] A mirror assembly is used to form a multiplexed optical path, so that the seed laser to be amplified passes through the disk crystal four times in the multiplexed optical path to achieve laser amplification.
[0011] The seed laser emitted by the seed light source, in the first polarization state, remains in the first polarization state after passing through the first conversion component along the first direction. After passing through the second conversion component, it becomes the second polarization state laser. The second polarization state laser is amplified four times by the disk crystal after passing through the reflector assembly and then returns to the second conversion component along the second direction, becoming the third polarization state laser. The returning laser then passes through the second conversion component along the first direction, becoming the fourth polarization state laser. The fourth polarization state laser is amplified four times by the disk crystal after passing through the reflector assembly and then returns to the second conversion component along the second direction, becoming the first polarization state laser. The first polarization state laser enters the first conversion component and is transformed into the third polarization state laser before being output.
[0012] In some embodiments, the second transformation component includes:
[0013] The second quarter-wave plate is configured to provide a phase difference of π / 4 for polarized light transmitted through the second quarter-wave plate.
[0014] In some embodiments, the reflector assembly includes: a first reflector, a second reflector, a third reflector, a fourth reflector, a fifth reflector, and a sixth reflector; the second polarized laser is amplified four times sequentially by the first reflector, a disk crystal, the second reflector, the fifth reflector, the third reflector, a disk crystal, the fourth reflector, a disk crystal, the third reflector, the fifth reflector, the second reflector, a disk crystal, and the first reflector; then it is converted into a third polarized laser by a second conversion assembly; the third polarized laser returns via the sixth reflector and is again converted into a fourth polarized laser by the second conversion assembly; the fourth polarized laser is then amplified four times sequentially by the first reflector, a disk crystal, the second reflector, the fifth reflector, the third reflector, a disk crystal, the fourth reflector, a disk crystal, the third reflector, the fifth reflector, the second reflector, a disk crystal, and the first reflector.
[0015] In some embodiments, the first polarization state is horizontal polarization, the second polarization state is left-handed circular polarization, the third polarization state is vertical polarization, and the fourth polarization state is right-handed circular polarization.
[0016] In some embodiments, it also includes:
[0017] A first polarizing beam splitter is disposed between the seed light source and the first conversion component, and configured to allow the first polarized laser to pass through.
[0018] In some embodiments, it also includes:
[0019] A second polarization beam splitter is disposed between the first conversion component and the second conversion component, and is configured to allow the first polarization state laser to pass through.
[0020] In some embodiments, the first, second, third, fourth, fifth, and sixth reflectors are all 0-degree reflectors, and the 0-degree reflectors perform total internal reflection of laser light incident at 0±10 degrees.
[0021] In some embodiments, it also includes:
[0022] A 45-degree reflector is used to output the third polarized laser.
[0023] In some embodiments, the disk crystal material is Yb:YAG, with a doping concentration of 5% to 20%, a diameter ≥ 10 mm, and a thickness of 100 to 500 µm.
[0024] Compared with the prior art, the above-described solutions of this application have at least the following beneficial effects:
[0025] This application proposes a disk multiplexer with a four-fold optical path. Compared with a conventional disk laser multiplexer, the amplifier equipped with the four-fold multiplexed optical path passes through the gain crystal four times more times than the amplifier without this optical path. Thus, under the same amplification number, the optical path of the disk laser multiplexer can be simplified to 1 / 4, thereby greatly simplifying the optical path structure of the disk laser multiplexer and reducing the size of the amplifier. Attached Figure Description
[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:
[0027] Figure 1 A schematic diagram of the structure of a four-way multiplexed disk laser multipass amplifier provided in an embodiment of this application.
[0028] Explanation of reference numerals in the attached figures:
[0029] In the diagram: Seed light source 1, first polarizing beam splitter 2-1, second polarizing beam splitter 2-2, Faraday rotator 3, first wave plate 4-1, second 1 / 4 wave plate 4-2, first reflecting mirror 5-1, second reflecting mirror 5-2, third reflecting mirror 5-3, fourth reflecting mirror 5-4, disc crystal 6, pumping device 7, fifth reflecting mirror 8, sixth reflecting mirror 9, 45-degree reflecting mirror 10. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0031] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the article or device that includes said element.
[0032] Because the thickness of the disc-shaped gain crystal is very thin, typically 100~300 μm, the amplification of the seed light after a single pass is relatively small. It needs to pass through multiple times to continuously extract pump energy. This requires a corresponding reflection optical path to enable the seed light to pass through the gain crystal multiple times. The more times it passes through, the more complex the corresponding optical path becomes.
[0033] To address the problem of complex optical paths in existing disc laser multipass amplifiers, this application proposes a disc multipass amplifier with a four-fold multiplexed optical path. Compared to conventional disc laser multipass amplifiers, the amplifier equipped with the four-fold multiplexed optical path passes through the gain crystal four times more times than the amplifier without this optical path. Thus, under the same amplification number, the optical path of the disc laser multipass amplifier can be simplified to 1 / 4, thereby significantly simplifying the optical path structure of the disc laser multipass amplifier.
[0034] The following is in conjunction with the appendix Figure 1 Detailed description of optional embodiments of the present invention.
[0035] like Figure 1 As shown, this application proposes an optical path quadruple-multiplexed disk laser multipass amplifier, comprising:
[0036] The disk crystal 6 is used to realize laser amplification; in some embodiments, the disk crystal 6 is made of Yb:YAG, with a doping concentration of 5% to 20%, a diameter ≥ 10 mm, and a thickness of 100 to 500 µm.
[0037] Pumping device 7, with a pump wavelength of 940 nm or 969 nm, functions to direct pump light onto the disk crystal 6.
[0038] Provides the energy required for the disk crystal 6;
[0039] Seed light source 1 is used to provide a seed laser with a first polarization state to be amplified; seed light source 1 emits horizontally polarized laser with a wavelength of 1030±5 nm;
[0040] The first conversion component is configured to not change the polarization state of the laser passing through the first conversion component along the first direction, but to change the polarization state of the laser passing through the first conversion component along the opposite second direction;
[0041] The second conversion component is used to change the polarization state of the laser light passing through the second conversion component;
[0042] A mirror assembly is used to form a multiplexed optical path, so that the seed laser to be amplified passes through the disk crystal 6 four times in the multiplexed optical path to achieve laser amplification.
[0043] The seed laser emitted by the seed light source, in the first polarization state, remains in the first polarization state after passing through the first conversion component along the first direction. After passing through the second conversion component, it becomes the second polarization state laser. The second polarization state laser is amplified four times by the disk crystal after passing through the reflector assembly and then returns to the second conversion component along the second direction, becoming the third polarization state laser. The returning laser then passes through the second conversion component along the first direction, becoming the fourth polarization state laser. The fourth polarization state laser is amplified four times by the disk crystal after passing through the reflector assembly and then returns to the second conversion component along the second direction, becoming the first polarization state laser. The first polarization state laser enters the first conversion component and is transformed into the third polarization state laser before being output.
[0044] The disc multiplexer proposed in this application uses a mirror assembly and a disc crystal to form a four-fold multiplexed optical path. During the optical path multiplexing process, the seed laser passes through the gain crystal four times more times than when the optical path is not equipped with this optical path. Thus, under the same amplification, the optical path of the disc laser multiplexer can be simplified to 1 / 4 by using the multiplexed optical path, thereby greatly simplifying the optical path structure of the disc laser multiplexer.
[0045] In some embodiments, the first transformation component includes a Faraday rotator 3 and a first waveplate 4-1. The first transformation component is configured to maintain the polarization state of the laser along a first direction from the Faraday rotator 3 to the first waveplate 4-1, and to change the polarization state of the laser along a second direction from the first waveplate 4-1 to the Faraday rotator 3. The Faraday rotator 3 has an aperture ≥ 1 mm and is used in combination with a quarter-waveplate. Its function is to maintain the polarization state of horizontally polarized laser transmitted from left to right, and to change the polarization state of horizontally polarized laser transmitted from right to left to vertically polarized laser. The first waveplate 4-1 has an aperture ≥ 1 mm and its function is to provide a π / 4 phase difference for the transmitted light.
[0046] In some embodiments, the second transformation component includes a second quarter-wave plate 4-2, which is configured to provide a π / 4 phase difference to polarized light transmitted through the second quarter-wave plate 4-2.
[0047] In some embodiments, the reflector assembly includes: a first reflector 5-1, a second reflector 5-2, a third reflector 5-3, a fourth reflector 5-4, a fifth reflector 8, and a sixth reflector 9; the second polarized laser sequentially passes through the first reflector 5-1, the disk crystal 6, the second reflector 5-2, the fifth reflector 8, the third reflector 5-3, the disk crystal 6, the fourth reflector 5-4, the disk crystal 6, the third reflector 5-3, the fifth reflector 8, the second reflector 5-2, the disk crystal 6, and the first reflector 5-1. The laser beam is amplified once, then transformed into a third polarization state by a second conversion component. This third polarization state laser returns via a sixth reflector and is again transformed into a fourth polarization state by the second conversion component. The fourth polarization state laser then undergoes four further amplifications sequentially through the first reflector 5-1, the disk crystal 6, the second reflector 5-2, the fifth reflector 8, the third reflector 5-3, the disk crystal 6, the fourth reflector 5-4, the disk crystal 6, the third reflector 5-3, the fifth reflector 8, the second reflector 5-2, the disk crystal 6, and the first reflector 5-1. The first reflector 5-1, the second reflector 5-2, the third reflector 5-3, the fourth reflector 5-4, the fifth reflector 8, and the sixth reflector 9 are all 0-degree reflectors with a diameter ≥10 mm. The function of the 0-degree reflectors is to perform total internal reflection of laser light incident within a 0±10 degree range. A mirror array composed of 0-degree mirrors can be increased in number to increase the amplification throughput, i.e., the number of times the seed light passes through the disk crystal. At the same time, since the incident / reflection angle of the 0-degree mirrors is extremely small, the overall width of the space occupied by each mirror can be greatly compressed, so that multiple reflected light paths can be arranged in a smaller space, thereby further reducing the size of the amplifier.
[0048] In some embodiments, the first polarization state is horizontal polarization, the second polarization state is left-handed circular polarization, the third polarization state is vertical polarization, and the fourth polarization state is right-handed circular polarization.
[0049] In some embodiments, a first polarizing beam splitter 2-1 is further included. The first polarizing beam splitter 2-1 is disposed between the seed light source 1 and the first conversion component and configured to allow the first polarized laser to pass through. The function of the first polarizing beam splitter 2-1 is to ensure high transmission of horizontally polarized laser and high reflection of vertically polarized laser, with the incident light making an angle of 45 degrees or 56 degrees with the normal of the lens, and the diameter of the polarizing beam splitter is ≥10 mm.
[0050] In some embodiments, a second polarizing beam splitter 2-2 is further included. The second polarizing beam splitter 2-2 is disposed between the first conversion component and the second conversion component and configured to allow the first polarized laser to pass through. The function of the second polarizing beam splitter 2-2 is to ensure high transmission of horizontally polarized laser and high reflection of vertically polarized laser, with the incident light making an angle of 45 degrees or 56 degrees with the normal of the lens, and the diameter of the polarizing beam splitter is ≥10 mm.
[0051] In some embodiments, the first reflector 5-1, the second reflector 5-2, the third reflector 5-3, the fourth reflector 5-4, the fifth reflector 8, and the sixth reflector 9 are all 0-degree reflectors, and the 0-degree reflectors reflect laser light incident at 0±10 degrees in total.
[0052] In some embodiments, a 45-degree reflector 10 is further included for outputting the third polarized laser. The 45-degree reflector 10 has a diameter ≥ 10 mm and its function is to perform total internal reflection of laser light incident within a 45±10 degree range.
[0053] This application proposes a disk multiplexer with a four-fold optical path. Compared with a conventional disk laser multiplexer, the amplifier equipped with the four-fold multiplexed optical path passes through the gain crystal four times more times than the amplifier without this optical path. Thus, under the same amplification number, the optical path of the disk laser multiplexer can be simplified to 1 / 4, thereby greatly simplifying the optical path structure of the disk laser multiplexer and reducing the size of the amplifier.
[0054] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.
[0055] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A four-way multiplexed optical disk laser multipass amplifier, characterized in that, include: Disc crystals are used to achieve laser amplification; A seed light source is used to provide a seed laser with a first polarization state to be amplified; The first conversion component is configured to not change the polarization state of the laser passing through the first conversion component along the first direction, but to change the polarization state of the laser passing through the first conversion component along the opposite second direction; The second conversion component is used to change the polarization state of the laser light passing through the second conversion component; A mirror assembly is used to form a multiplexed optical path, so that the seed laser to be amplified passes through the disk crystal four times in the multiplexed optical path to achieve laser amplification. The seed laser emitted by the seed light source, in the first polarization state, remains in the first polarization state after passing through the first conversion component along the first direction. After passing through the second conversion component, it becomes the second polarization state laser. The second polarization state laser is amplified four times by the disk crystal after passing through the reflector assembly and then returns to the second conversion component along the second direction, becoming the third polarization state laser. The returning laser then passes through the second conversion component along the first direction, becoming the fourth polarization state laser. The fourth polarization state laser is amplified four times by the disk crystal after passing through the reflector assembly and then returns to the second conversion component along the second direction, becoming the first polarization state laser. The first polarization state laser enters the first conversion component and is transformed into the third polarization state laser before being output.
2. The multi-pass amplifier according to claim 1, characterized in that, The second transformation component includes: The second quarter-wave plate is configured to provide a phase difference of π / 4 for polarized light transmitted through the second quarter-wave plate.
3. The multi-pass amplifier according to claim 1, characterized in that, The reflector assembly includes: a first reflector, a second reflector, a third reflector, a fourth reflector, a fifth reflector, and a sixth reflector. The second polarized laser is amplified four times sequentially by the first reflector, a disk crystal, the second reflector, the fifth reflector, the third reflector, a disk crystal, the fourth reflector, a disk crystal, the third reflector, the fifth reflector, the second reflector, a disk crystal, and the first reflector. Then, it is transformed into a third polarized laser by a second conversion assembly. The third polarized laser returns via the sixth reflector and is transformed into a fourth polarized laser by the second conversion assembly again. The fourth polarized laser is then amplified four times sequentially by the first reflector, a disk crystal, the second reflector, the fifth reflector, the third reflector, a disk crystal, the fourth reflector, a disk crystal, the third reflector, the fifth reflector, the second reflector, a disk crystal, and the first reflector.
4. The multi-pass amplifier according to claim 1, characterized in that, The first polarization state is horizontal polarization, the second polarization state is left-handed circular polarization, the third polarization state is vertical polarization, and the fourth polarization state is right-handed circular polarization.
5. The multi-pass amplifier according to claim 1, characterized in that, Also includes: A first polarizing beam splitter is disposed between the seed light source and the first conversion component, and configured to allow the first polarized laser to pass through.
6. The multi-pass amplifier according to claim 1, characterized in that, Also includes: A second polarization beam splitter is disposed between the first conversion component and the second conversion component, and is configured to allow the first polarization state laser to pass through.
7. The multi-pass amplifier according to claim 3, characterized in that, The first, second, third, fourth, fifth, and sixth reflectors are all 0-degree reflectors, and the 0-degree reflectors reflect laser light incident at 0±10 degrees.
8. The multi-pass amplifier according to claim 3, characterized in that, Also includes: A 45-degree reflector is used to output the third polarized laser.
9. The multi-pass amplifier according to claim 1, characterized in that, The disk crystal is made of Yb:YAG, with a doping concentration of 5% to 20%, a diameter of ≥10 mm, and a thickness of 100 to 500 µm.