Beam quality analysis of solid-state zigzag tube lasers for long-distance propagation in atmosphere
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摘要: “之字形”光路薄管固体激光是一种结构紧凑、增益高且利于发射的新型激光光源。针对薄管固体激光光源及其大气长程传输过程中的光束质量退化问题，提出了基于直角锥面变形镜的薄管激光校正方法，进而通过建立薄管激光校正模型以及大气长程传输模型，开展了薄管激光大气长程传输光束质量分析。首先，针对大遮拦比窄环宽环形光束与发射系统的匹配问题，提供了一种薄管激光环形光束整形变换方案，有效实现了薄管激光的整形和变换。然后，分析了薄管激光光源光束质量、大气湍流效应和热晕效应等对整形变换后的薄管激光大气长程传输特性的影响，进而明确了薄管激光大气长程传输光束质量退化机理。最后，分析了直角锥面变形镜对薄管激光的光源畸变、大气湍流的低频分量和热晕导致的离焦相位等的校正效果。结果表明，经过直角锥面变形镜的校正，薄管激光光源光束质量明显改善，大气长程传输后的远场光束质量有所提高。若进一步配合常规变形镜进行联合校正，薄管激光大气长程传输后的远场光束质量可得到显著提升。Abstract: Solid-state zigzag tube laser (SSZTL) is a new type of solid-state laser source with structural compactness, high gain, as well as direct transmitting. To solve the problem that the beam quality of the tube laser significantly degrades during long-distance propagation in atmosphere, the method for improving the beam quality of the tube laser based on the right-angle conical deformable mirror have been proposed. The beam correction model and the beam propagation model in atmosphere of the tube laser have been built up and the beam quality of the tube laser after long-distance propagation in atmosphere have been analyzed. Firstly, a scheme for obscuration ratio transformation of annular tube lasers have been provided, based on which the matching of the small-aperture large-obscuration-ratio tube laser and the large-aperture small-obscuration-ratio Cassegrain system have been accomplished. Then, the impacts of the beam quality of the tube laser source, the atmosphere turbulence effect and the thermal blooming effect on the propagation characteristics of SSZTLs have been numerically studied, and the mechanism of the beam quality degradation of the tube laser in the procedure of the long-distance propagation in atmosphere have been revealed. To improve the beam quality of the tube laser in far field, the right-angle conical deformable mirror have been used to correct the aberrations of the tube laser source and the phase distortions induced by the turbulence and thermal blooming effects in atmosphere. The results show that the beam quality of the laser source have been significantly improved after correction. Also, the Strehl ratio in far field have been obviously improved, especially used together with conventional deformable mirror.
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图 1 基于直角锥面变形镜的薄管激光校正方案
Figure 1. Schematic illustration of solid-state zigzag tube lasers (SSZTLs) correction based on the right-angle conical deformable mirror (RCDM)
图 2 薄管激光整形变换系统
Figure 2. Schematic illustration of obscuration ratio transformation system
图 3 扰动介质中光场传输求解流程示意图
Figure 3. Schematic illustration of beam propagation in perturbated medium
图 5 薄管激光在5 km自由空间中传输后的靶面光场分布：（a）同心度误差Δx=1 μm；（b）平行度误差Δθ=20 μrad；（c）锥度误差Δa=200 μrad；（d）光源平行度误差Δθs=100 μrad；（e）全部误差。
Figure 5. Intensity distribution of annular laser beam on target plane after 5 km propagation in free space with (a) concentricity error Δx=1 μm; (b) parallelism error of tube Δθ=20 μrad; (c) taper error Δa=200 μrad; (d) parallelism error of source Δθs=100 μrad; (e) errors。
图 6 校正前后薄管激光的远场光束质量
Figure 6. Beam quality of annular laser beams before and after correction
图 7 薄管激光在5 km大气湍流中传输后的靶面光场分布：（a）Cn2=1×10−14；（b）Cn2=1×10−15。
Figure 7. Intensity distribution of annular laser beam on target plane after 5 km propagation in turbulence: (a) Cn2=1×10−14; (b) Cn2=1×10−15.
图 8 光斑平均半径
$ \overline w $ 和质心漂移Δr随传输距离的变化Figure 8. Variation of
$ \overline w $ and Δr of laser beam for different propagation distance
图 9 高功率薄管激光5 km传输后的靶面光场分布（稳态热晕）
Figure 9. Intensity distribution of high-power annular laser beam on target plane after 5 km propagation (steady-state thermal blooming)
图 10 光斑平均半径
$ \overline w $ 和质心漂移Δr随传输距离的变化（直角锥面变形镜校正）Figure 10. Variation of
$ \overline w $ and Δr of laser beam for different propagation distance (with correction by right-angle conical deformable mirror)
图 11 靶面光斑平均半径
$ \overline w $ 和质心漂移Δr随传输距离的变化（137单元变形镜校正）Figure 11. Variation of
$ \overline w $ and Δr of laser beam for different propagation distance (with correction by 137-unit deformable mirror) -
[1] Savich M. High power tube solid-state laser with zigzag propagation of pump and laser beam[C]//Proceedings of SPIE 9342, Solid State Lasers XXIV: Technology and Devices. 2015: 934216. [2] Tian Boyu, Zhong Zheqiang, Huang Cong, et al. Analysis on beam quality of solid-state tube MOPA system with zigzag beam path[J]. IEEE Photonics Journal, 2019, 11: 1501311. [3] Wittrock U, Weber H, Eppich B. Inside-pumped Nd: YAG tube laser[J]. Optics Letters, 1991, 16(14): 1092-1094. doi: 10.1364/OL.16.001092 [4] Tian Boyu, Yu Jiangchuan, Zhang Bin. Theoretical study on beam quality and thermal stability in solid-state zigzag tube laser amplifier[J]. Optical Engineering, 2020, 59: 076104. [5] Williams M D, Conway E J. Space laser power transmission system studies[R]. Langley: NASA, 1982. [6] Cook J R, Albertine J R. The Navy’s high-energy laser weapon system[C]//Proceedings of SPIE 2988, Free-Electron Laser Challenges. 1997: 264-271. [7] Venkatesan K. The study on force, surface integrity, tool life and chip on laser assisted machining of Inconel 718 using Nd: YAG laser source[J]. Journal of Advanced Research, 2017, 8(4): 407-423. doi: 10.1016/j.jare.2017.05.004 [8] Sun Chuang, Wang Deen, Deng Xuewei, et al. Numerical analysis of a novel two-stage enlargement and adaptive correction approach for the annular aberration compensation[J]. Optics Express, 2019, 27(18): 25205-25227. doi: 10.1364/OE.27.025205 [9] Herman B J, Strugala L A. A. Method for inclusion of low-frequency contributions in numerical representation of atmospheric turbulence[C]//Proceedings of SPIE 1221, Propagation of High-Energy Laser Beams Through the Earth's Atmosphere. 1990: 183-192. [10] Zhang Yuqiu, Ji Xiaoling, Li Xiaoqing, et al. Thermal blooming effect of laser beams propagating through seawater[J]. Optics Express, 2017, 25(6): 5861-5875. doi: 10.1364/OE.25.005861 [11] 何婷, 田博宇, 邱蝶, 等. 基于直角锥面变形镜的薄管激光光束质量提升新方法[J/OL]. 物理学报. (2021-05-10). https://kns.cnki.net/KCMS/detail/detail.aspx?dbcode=CJFQ&dbname=CAPJLAST&filename=WLXB20210506004.He Ting, Tian Boyu, Qiu Die, et al. Novel method for improving beam quality of thin-wall tube laser based on right-angle cone deformable mirror[J/OL]. Acta Physica Sinica. (2021-05-10). https://kns.cnki.net/KCMS/detail/detail.aspx?dbcode=CJFQ&dbname=CAPJLAST&filename=WLXB20210506004 [12] Laslandes M, Hugot E, Ferrari M. Active optics: deformation systems compensating for optical aberrations with a minimum number of actuators[C]//Proceedings of SPIE 8450, Modern Technologies in Space- and Ground-based Telescopes and Instrumentation II. 2012: 84500J. [13] 余江川, 田博宇, 钟哲强, 等. 大遮拦比薄管激光环域像差校正方法[J]. 中国激光, 2020, 47:0905001. (Yu Jiangchuan, Tian Boyu, Zhong Zheqiang, et al. Method for annular aberration correction of large-aperture thin-wall tube lasers[J]. Chinese Journal of Lasers, 2020, 47: 0905001 doi: 10.3788/CJL202047.0905001 [14] 李佳, 田博宇, 余江川, 等. 双管级联薄管激光放大器环域像差自补偿方法[J]. 中国激光, 2021, 48:1301006. (Li Jia, Tian Boyu, Yu Jiangchuan, et al. Method for self-correction of annular off-axis aberrations in two-stage tube laser amplifiers[J]. Chinese Journal of Lasers, 2021, 48: 1301006 [15] Arora R K, Lu Z. Graphical study of Laguerre-Gaussian beam modes[J]. IEE Proceedings—Microwaves, Antennas and Propagation, 1994, 141(3): 145-150. doi: 10.1049/ip-map:19941111 [16] Fleck Jr J A, Morris J R, Feit M D. Time-dependent propagation of high energy laser beams through the atmosphere[J]. Applied Physics, 1976, 10(2): 129-160. doi: 10.1007/BF00896333 [17] Walsh J L, Ulrich P B. Thermal blooming in the atmosphere[M]//Strohbehn J W. Laser beam propagation in the atmosphere. Berlin Heidelberg: Springer, 1978: 223-320. [18] Landau L D, Lifshitz E M. Course of theoretical physics, Vol. 6 Fluid mechanics[M]. Oxford: Pergamon Press, 1959: 6. [19] 杜祥琬. 实际强激光远场靶面上光束质量的评价因素[J]. 中国激光, 1997, 24(4):327-332. (Du Xiangwan. Factors for evaluating beam quality of a real high power laser on the target surface in far field[J]. Chinese Journal of Lasers, 1997, 24(4): 327-332 doi: 10.3321/j.issn:0258-7025.1997.04.010 [20] Mahajan V N. Strehl ratio of a Gaussian beam[J]. Journal of the Optical Society of America A: Optics, Image Science, and Vision, 2005, 22(9): 1824-1833. doi: 10.1364/JOSAA.22.001824 [21] Tian Boyu, Yu Jiangchuan, Zhang Bin. A method for generating LG0l vortex beams with tunable topological charges based on tube lasers[J]. Optics Communications, 2021, 491: 126939. doi: 10.1016/j.optcom.2021.126939 [22] 林旭东, 刘欣悦, 王建立, 等. 基于压电陶瓷促动器的连续镜面变形镜研制进展[J]. 激光与光电子学进展, 2014, 51:090003. (Lin Xudong, Liu Xinyue, Wang Jianli, et al. Progress of the continuous surface deformable mirror based on piezo-ceramic actuator[J]. Laser & Optoelectronics Progress, 2014, 51: 090003 -
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