紧凑高效高光束质量千赫兹Nd∶YAG MOPA激光器  

Compact,Efficient and High-Beam-Quality Nd∶YAG MOPA Laser System Operating at 1 kHz Repetition Rate

作　　者：池静 钟凯[1,2,3] 李方杰 乔鸿展[1,2,3] 孙悦 郑逸哲 刘宇鑫[1,2,3] 徐德刚 姚建铨 Chi Jing;Zhong Kai;Li Fangjie;Qiao Hongzhan;Sun Yue;Zheng Yizhe;Liu Yuxin;Xu Degang;Yao Jianquan(College of Precision Instrument and Opto-Electronics Engineering,Tianjin University,Tianjin 300072,China;Key Laboratory of Optoelectronics Information Technology,Ministry of Education,Tianjin University,Tianjin 300072,China;Key Laboratory of Micro Optical Electronic Mechanical System Technology,Ministry of Education,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学精密仪器与光电子工程学院,天津300072 [2]天津大学光电信息技术教育部重点实验室,天津300072 [3]天津大学微光机电系统技术教育部重点实验室,天津300072

出　　处：《中国激光》2025年第2期35-42,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(62175184)。

摘　　要：报道了一种基于分光泵浦的紧凑电光调Q Nd∶YAG主振荡功率放大(MOPA)系统,其能够实现高脉冲能量、高稳定性和高光束质量的纳秒脉冲激光输出。振荡级采用YAG/Nd∶YAG键合晶体作为增益介质,在1 kHz的重复频率下输出的单脉冲能量为2.68 mJ,脉冲宽度为4.4 ns。利用球差自补偿的单级双通端面泵浦Nd∶YAG激光放大器,将单脉冲能量放大到9.37 mJ,脉冲宽度为4.63 ns,相应的峰值功率为2.02 MW,光-光转换效率达26.86%,平均功率在1 h内的均方根(RMS)不稳定度为0.094%。使用LiB_(3)O_(5)(LBO)晶体进行倍频实验,532 nm激光的单脉冲能量为4.98 mJ,脉冲宽度为3.5 ns。该MOPA激光系统可以作为高精度测距仪和高分辨率激光雷达的理想激光源。Objective Laser-diode(LD)-pumped solid-state lasers operating in the electro-optic(EO)Q-switching mode have broad application prospects in various fields,including ranging,imaging LIDAR,laser processing,remote sensing,and pumping nonlinear optical frequency converters.High repetition rate,short pulse width,high peak power,and high beam quality are the basic requirements for most of these applications to improve signal-to-noise ratio(SNR),measurement capability,ranging accuracy,and conversion efficiency.A compact size is also essential,especially for air-,space-,and rocket-borne systems.The diode-end-pumped electrooptically Q-switched laser has good beam quality and a compact structure;however,the pulse energy is quite limited because of the small mode size in the cavity.Thus,master oscillator power amplifier(MOPA)technology is necessary.In this study,a compact electro-optically Q-switched Nd∶YAG MOPA system based on split pumping and self-compensated spherical aberration is proposed to provide an effective technical approach for miniaturized high-repetition-rate lidar sources.Methods The electro-optically Q-switched Nd∶YAG MOPA system operating at 1 kHz is shown in Fig.1.To maintain a compact size and reduce cost and complexity,the laser oscillator and amplifier shared an LD pump source with maximum peak power of 170 W.The pump beam was separated by a beam splitter into two parts,30%(10.6 mJ)and 70%(24.28 mJ),which were incident onto the oscillator and amplifier,respectively.This structure does not require additional pulse synchronization electronics;therefore,it is simple,compact,and stable.The oscillator produces a high-quality seeding beam with considerable pulse energy,which then proceeds to a specially designed double-pass amplifier for power amplification.By placing a 1064-nm reflector(M6)at the focus of the thermal lens in the amplification stage,the thermally induced spherical aberration by the gain medium during the first pass undergoes a sign reversal at M6.Upon passing through the gain medium for t

关 键 词：激光器与激光光学 激光放大器 电光调Q 分光泵浦 球差自补偿 

分 类 号：TN248.1[电子电信—物理电子学]