光学 精密工程, 2011, 19 (2): 397, 网络出版: 2011-03-30
平滑化窄脉冲高功率准分子激光放大技术
Amplification of high power short pulse excimer laser with beam smoothing
摘要
对于高功率准分子激光,光学角多路和诱导空间非相干(EFISI)光束平滑是高功率准分子激光压缩脉宽、提高功率密度和实现靶面均匀辐照的有效途径,其应用涉及前端至靶前的各个环节,主要体现为平滑化窄脉冲激光的传输放大问题。首先介绍了基于散射法开展的部分相干源前端技术及脉冲整形的初步研究结果,利用直接法和反射率耦合方法,研究了5台激光放大器增益特性。然后,讨论了窄脉宽激光放大时的自发辐射放大(ASE)控制技术,最后,介绍了窄脉冲激光放大实验系统。实验获得了预期的实验结果,输出能量为5~6 J,激光脉宽约10 ns,聚焦光斑约Φ300 μm。单路系统实验结果表明,系统放大链和光学设计合理,基本满足角多路MOPA系统的技术验证要求,为系统工程设计奠定基础。
Abstract
The combination of optical angular mutiplexing and Echelon Free Induced Spatial Incoherence (EFISI) is a best choice for the pulse compression and beam smoothing in a high power excimer laser system, which relates to the transportation and amplification of smoothed narrow laser pulse mainly. In this paper, the construction of a partial coherence oscillator by scattering method was described and primary results for pulse shaping were provided. Then, the gain characteristics for five laser amplifiers by single-pass amplifications and simulations of different output couplings were discussed, and measures to control over Amplification Spontaneous Emission (ASE) in the short laser pulse amplification was described. Finally,the Main Oscilation Power Amplifer(MOPA) chain of a single-beam XeCl laser and primary results were introduced. Obtained results show that the final output energy is 5-6 J with a pulsewidth around 10 ns and the focal spot is around 300 μm in the diameter. These results indicate that the laser chain and optical design are reasonable, which can be used as a good guide for the specific design of full scale angular multiplexed laser MOPA system.
赵学庆, 刘晶儒, 易爱平, 薛全喜, 华恒祺, 钱航, 郑国鑫, 胡云, 张永生, 黄珂, 黄超, 于力. 平滑化窄脉冲高功率准分子激光放大技术[J]. 光学 精密工程, 2011, 19(2): 397. ZHAO Xue-qing, LIU Jing-ru, YI Ai-ping, XUE Quan-xi, HUA Heng-qi, QIAN Hang, ZHENG Guo-xin, HU Yun, ZHANG Yong-sheng, HUANG Ke, HUANG Chao, YU Li. Amplification of high power short pulse excimer laser with beam smoothing[J]. Optics and Precision Engineering, 2011, 19(2): 397.