1 上海大学通信与信息工程学院特种光纤与光接入网重点实验室, 上海 200444
2 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
在使用高功率激光装置进行物理实验时,高精度时间同步的时标系统是实现物理过程精确诊断的必要条件。为了满足物理实验需求,该系统采用任意波形发生器输出信号时分复用结合高速电光调制的技术方案,同源产生了主激光、时标光、电时标和高精度触发信号等多路信号。时标系统共可输出532,355,266 nm三种波长共10路梳状时标光信号及8路梳状电时标信号、两路快前沿高幅值触发信号。时标信号与主激光时间同步抖动峰峰值达到12.80 ps,梳状时标光信号脉冲周期峰值抖动为6.40 ps,接近目前采用的测量系统极限。完成了时标系统在高功率激光装置中的应用演示,满足了诊断设备应用要求;对条纹相机不同扫程进行时间基准标定实验,可有效校准相机大扫程的时间误差。
激光光学 时标系统 高精度时间同步 任意波形发生器 条纹相机 中国激光
2019, 46(11): 1101011
Author Affiliations
Abstract
1 Key Laboratory of High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
3 University of Chinese Academy of Sciences, Beijing 100049, China
A high-power, Joule-class, nanosecond temporally shaped multi-pass ring laser amplifier system with two neodymium-doped phosphate glass (Nd:glass) laser heads is demonstrated. The laser amplifier system consists of three parts: an all-fiber structure seeder, a diode-pumped Nd:glass regenerative amplifier and a multi-pass ring amplifier, where the thermally induced depolarization of two laser heads is studied experimentally and theoretically. Following the injection of a square pulse with the pulse energy of 0.9 mJ and pulse width of 6 ns, a 0.969-J high-energy laser pulse at 1 Hz was generated, which had the ability to change the waveform arbitrarily, based on the all-fiber structure front end. The experimental results show that the proposed laser system is promising to be adopted in the preamplifier of high-power laser facilities.
depolarization compensation laser amplifier neodymium laser ring laser High Power Laser Science and Engineering
2019, 7(1): 010000e8
Author Affiliations
Abstract
National Laboratory on High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
A high power laser system was used to drive the ignition of inertial confinement fusion (ICF), of which the high energy, the uniform focal spot, the accurate laser waveform, and the synchronization between the laser beams are key parameters. To accomplish this, global laser characteristics control should be assured, which was the main purpose of the injection laser system. In this paper, the key technological progress involved in the improvement of the performance of the injection laser of SG-II is reported, including frequency domain control, time domain control, near-field spatial shaping, pre-amplifier technology, and the optical parametric chirped pulse amplification pump source.
amplifier injection laser pulse shaping spatial shaping synchronization. High Power Laser Science and Engineering
2018, 6(2): 02000e34
Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 National Laboratory on High Power Laser and Physics, Shanghai 201800, China
We demonstrate a laser diode end-pumped helium gas-cooled multislab Nd:glass laser amplifier. The design and thermal management of the proposed laser amplifier are discussed. The thermally induced wavefront aberration of the slabs was also measured and compared with simulation results. A small-signal single-pass longitudinal gain of 1.8 was measured with a pump energy of 7.3 J. With an injected seed energy of 0.6 mJ, the output energy from the amplifier reached 0.5 J at 0.2 Hz and 0.43 J at 0.5 Hz in a multipass extraction geometry, thus demonstrating the feasibility of diode-pumped, high-energy lasers with direct gas cooling.
laser diode gas cooling Nd:glass wavefront aberration laser amplifier. High Power Laser Science and Engineering
2018, 6(2): 02000e15
中国科学院上海光学精密机械研究所, 上海 201800
理论分析了基于边缘加热条件下气冷钕玻璃放大器的热致波前畸变, 模拟计算了不同加热温度下钕玻璃片的温度分布和热波前畸变分布, 并进行了实验验证。结果表明, 数值模拟与实验结果能较好地吻合, 在产热率为0.6 W/cm3时, 钕玻璃片产生的热波前畸变随着边缘温度的增加而减小, 而当边缘温度达到90 ℃时, 热波前畸变开始出现反转, 随温度增加而增加。合理设计边缘加热结构和优化加热温度, 能有效抑制气冷钕玻璃放大器的热波前畸变。
激光光学 热畸变 边缘加热 钕玻璃 氦气冷却 激光放大器
Author Affiliations
Abstract
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室， 上海 201800
2 中国科学院大学, 北京 100049
When high-power solid laser working in high repetition rate, the laser output wave-front changes due to the thermal distortion, which is caused by the gain medium under the heat deposition. Therefore, the coherent modulation imaging technology is used to realize the measurement of the laser output wave-front from one frame of diffraction intensity recorded. The phases of thermal distortion of the optical element are obtained when the amplifier working in 1, 5, 7 Hz frequency. Experimental results show that thermal distortion effect is significantly increased, the heat is concentrated toward the center region and the phase change increases as the working frequency increases.
测量 高功率激光 波前测量 相位恢复 热畸变 相干调制成像 measurement high-power laser wave-front measurement phase recovery thermal distortion coherent modulation imaging Collection Of theses on high power laser and plasma physics
2016, 14(1): 1101002
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室， 上海 201800
2 中国科学院大学, 北京 100049
高功率固体激光器工作在高重复频率时，增益介质因热量的沉积而发生热畸变，导致激光输出波前发生变化。为此，利用相干调制成像技术通过记录单幅衍射光斑实现输出光场的波前测量，获得了放大器工作在1,5,7 Hz频率时光学元件的热畸变相位。实验结果显示，随着工作频率增大，热量向中心区域集中，热沉积效应明显增加了波前变化。
测量 高功率激光 波前测量 相位恢复 热畸变 相干调制成像 中国激光
2016, 43(11): 1101002
Author Affiliations
Abstract
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
2 中国科学院大学, 北京 100049
Laser diode pumped solid-state lasers (DPSSL) has become an important way to realize the next generation of laser-driven device for energy conversion efficiency and repetition rate requirements. High repetition frequency leads to heat accumulation on the memory medium, which will cause thermo-optical effect, elasto-optical effect and bulk displacement, then resuls in the generation of wavefront distortion and affects the beam quality. Aimed at 100 J output energy and 10 Hz repetition frequency amplifier module, the extraction efficiency and gain performance storage are analyzed, and the sheet laser diode pumped amplifier module structure is designed using gas cooling technology. Thermal analysis models of single slice amplifier are established using the finite element analysis. The influence of signal slice thickness and convective heat transfer coefficient to the wavefront distortion are researched, in consideration of the limitation of the total wavefront distortion, we obtain the optimal value of single slice thickness. Using super-Gaussian beam on behalf of pump source and considering the distribution of helium gas flow, we analysis the thermal designed data and simulate the temperature, bulk displacement and stress distribution to get the related wavefront distortions.
激光技术 有限元分析 二极管抽运 气冷技术 片状放大器 波前畸变 laser technique finite element analysis diode pumping gas-cooled slice amplifier wavefront distortion Collection Of theses on high power laser and plasma physics
2014, 12(1): 1002001
Author Affiliations
Abstract
1 Shanghai Key Laboratory of All Solid-state Laser and Applied Techniques, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 The Joint Laboratory for High Power Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
A diode-pumped master oscillator power amplifier system based on a cryogenic Yb:YAG active-mirror laser has been developed. The performances of the laser amplifier at low temperature and room temperature have been investigated theoretically and experimentally. A maximum output energy of 3.05 J with an optical-to-optical efficiency of 14.7% has been achieved by using the master amplifier system.
diode-pumped solid-state laser Yb:YAG High Power Laser Science and Engineering
2014, 2(3): 03000e18
1 中国科学院上海光学精密机械研究所高功率激光物理联合实验室, 上海 201800
2 中国科学院大学, 北京 100049
激光二极管抽运的固体激光器（DPSSL）成为实现下一代激光器驱动装置对能量转换效率和重复频率要求的重要途径。高重复频率导致介质内存在热积累，引起热光效应、弹光效应和形变，导致波前畸变的产生，影响光束质量。针对目标输出能量100 J，重复频率10 Hz的放大模块，分析其储能提取效率和增益性能，采用气体冷却技术，设计激光二极管抽运的片状放大模块结构。利用有限元数值分析方法，建立了该装置单片放大器热分析模型，研究了单片增益介质厚度、对流换热系数对波前畸变的影响，结合波前畸变的要求，得到了单片厚度的最优值，并对该设计进行热分析，利用超高斯光束近似抽运光源，结合氦气气流分布情况，模拟单片介质的温度、形变和应力分布，计算得到了热光效应、形变和弹光效应对波前畸变的贡献以及单片增益介质的总波前。
激光技术 有限元分析 二极管抽运 气冷技术 片状放大器 波前畸变 中国激光
2014, 41(10): 1002001
