1 中国科学院上海光学精密机械研究所高功率激光物理重点实验室，上海 201800
2 中国科学院大学，北京 100049
3 上海交通大学IFSA协同创新中心，上海 200240
4 中国工程物理研究院上海激光等离子体研究所，上海 201800
拍瓦激光系统中剩余的高阶色散导致了脉冲波形的振荡，影响了拍瓦激光的信噪比。为了进一步优化拍瓦激光的信噪比特性，满足激光加速电子、质子等粒子的效率提升需求，本文提出了一种基于双折射晶体的新型超短脉冲的三阶色散主动调控方法，用于信噪比的主动调控。通过数值分析模拟了双折射晶体引入的二阶色散、三阶色散，针对中心波长为1053 nm的拍瓦激光系统，选择适当的晶体厚度，可以通过调节双折射晶体的面内旋转角改变系统剩余三阶色散。同时，基于神光Ⅱ第九路拍瓦激光系统光参量啁啾脉冲放大（OPCPA）预压缩的信噪比测量值，对比了不同量级剩余三阶色散对脉冲信噪比的影响，得出通过改变拍瓦激光系统中剩余三阶色散量，可实现不同量级信噪比的主动调控的结论。该研究结果对于高能激光系统剩余三阶色散的补偿以及信噪比的优化具有重要意义。
激光器与激光光学 双折射晶体 三阶色散 信噪比 拍瓦激光 光学学报
2023, 43(10): 1014003
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
高功率激光装置是一个复杂的有源巨型光学工程，其性能指标要求逼近科学技术与物理极限。驱动器研制有物理设计、工程光学和结构工程设计三大过程，工程光学在其中起着重要作用。高功率激光装置工程光学设计需遵循其特有的设计原则和要点，以保证装置的高性能。根据驱动器设计指标和设计特点，从总体光学设计、光束质量控制以及光束打靶精度控制方面，综述了高功率激光装置工程光学设计中的关键科学技术问题以及相应解决方法，为未来高功率激光驱动器的发展提供必要的工程设计参考。
光学设计 惯性约束聚变 神光装置 工程光学 激光光学
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
3 中国工程物理研究院上海激光等离子体研究所, 上海 201800
提出一种标定超短脉冲测量装置时间分辨率的新方法。设计制作可产生特定时间延迟的平面平晶,标定时将其放置在自相关仪前的光路中;待测光脉冲经过平面平晶后会产生时间延迟为T的双脉冲,该双脉冲到达自相关晶体发生相互作用,产生自相关信号,此时信号的主峰两端会出现较为明显的次峰信号,该次峰信号之间的时间间隔为2T,这样双脉冲的时间延迟就转换为次峰信号峰值的空间距离,经CCD接收后可计算得到自相关仪的时间分辨率。采用此方法对自相关仪时间分辨率标定的结果为217.88 fs/pixel,与移动光程延迟器法得到的标定结果214.27 fs/pixel相比,相对误差仅为1.68%;与可单次标定的鉴别率板法相比,采用此方法标定结果的相对扩展不确定度为1.50%,优于鉴别率板法的6.96%。
1 上海科技大学物质科学与技术学院, 上海 201210
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
3 中国科学院大学材料与光电研究中心, 北京 100049
基于衍射重叠相位恢复术(PIE),提出一种新的平面偏振双折射测量方法。利用PIE测量方法,对样品在两种不同偏振状态下形成的暗场探测光复振幅进行重建,并分别从探测光相位及复振幅之比中简单准确地提取相位延迟量及方位角,实现了双折射样品的二维定量测量。采用双折射分辨率靶对所提方法进行实验验证,所得结果与分辨率靶实际分布完全相符,相位延迟量最大误差不超过23.9 nm,方位角误差为0.49°。该方法结构简单,能解决传统平面偏光仪无法实现定量双折射测量的难题,同时减少了PIE扫描的次数,缩短数据采集时间及处理流程,为大口径光学器件的双折射检测提供了一种实用方法。
测量 偏振检测 双折射 相位恢复 中国激光
2019, 46(12): 1204003
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
3 上海科技大学物质科学与技术学院, 上海 201210
提出了基于强度传输方程(TIE)的光学元件激光损伤应力检测方法, 通过采集损伤点区域聚焦位置附近的三幅强度图像, 直接计算出损伤点产生的应力双折射相位分布, 并在此基础上实现了激光损伤应力的定量检测。相较于其他相位测量技术, TIE方法在恢复的相位结果中不会出现幅度为π的相位跃变, 而且可以采用非相干光照明, 具有光路结构简单、操作方便和测量速度快等优势, 适用于光学元件损伤的快速检测。对石英玻璃在二氧化碳激光器作用下所产生的系列损伤点进行了实际验证测量, 测量结果完全符合理论预期。
测量 相位恢复 强度传输方程 应力双折射 损伤检测
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 University of Chinese Academy of Sciences, Beijing 100049, China
It is rare for a conventional direct detection method to measure the transmittance uniformity of mirrors with rigorous standards, especially to meet the requirement of transmittance/reflectance and phase detection simultaneously. In this study, a new method of self-calibrated balanced heterodyne detection (SCBHD) is proposed. It can be self-calibrated by a two-channel structure to overcome the environmental effects in large optics scanning detection by employing highly accurate heterodyne interference. A typical transmittance measurement experiment was performed at 1053 nm wavelength via SCBHD. A standard deviation (SD) of 0.038% was achieved in the preliminary experiment. The experimental results prove to reduce the SD by approximately two orders of magnitude compared with the conventional direct detection method in the same condition. The proposed method was verified as being promising not only for its wider dynamic measurement range and its higher accuracy but also for its simultaneous transmittance and phase detection ability.
120.3940 Metrology 240.6700 Surfaces 300.6490 Spectroscopy, surface Chinese Optics Letters
2018, 16(6): 061201
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国家实验室, 上海 201800
2 中国科学院大学, 北京 100049
In order to investigate the response law of different interferometers to the mid-spatial frequency errors and obtain the relatively true power spectral density (PSD) distribution, the 4D AccuFiz, ZYGO DynaFiz and ZYGO GPI interferometers are respectively used to measure the periodic ripples and scratch samples, and the comparative analysis of the measured one-dimension PSD curves is made. The results show that the responsivities to the mid- and high-spatial frequency information are different for different interferometers, and the higher the interferometer resolution is, the higher the responsivity is. The instrument transfer function (ITF) curve is used to correct the measured PSD, and the truer PSD distribution is obtained. However, in the range of some frequency bands, there still exist some difference between the ITF curve and the practical response.
测量 功率谱密度 干涉仪 中频波面误差 仪器传递函数 measurement power spectral density interferometer mid-spatial frequency wavefront error instrument transform function Collection Of theses on high power laser and plasma physics
2016, 14(1): 0904002
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国家实验室, 上海 201800
2 中国科学院大学, 北京 100049
In order to investigate the response law of different interferometers to the mid-spatial frequency errors and obtain the relatively true power spectral density (PSD) distribution, the 4D AccuFiz, ZYGO DynaFiz and ZYGO GPI interferometers are respectively used to measure the periodic ripples and scratch samples, and the comparative analysis of the measured one-dimension PSD curves is made. The results show that the responsivities to the mid- and high-spatial frequency information are different for different interferometers, and the higher the interferometer resolution is, the higher the responsivity is. The instrument transfer function (ITF) curve is used to correct the measured PSD, and the truer PSD distribution is obtained. However, in the range of some frequency bands, there still exist some difference between the ITF curve and the practical response.
测量 功率谱密度 干涉仪 中频波面误差 仪器传递函数 measurement power spectral density interferometer mid-spatial frequency wavefront error instrument transform function Collection Of theses on high power laser and plasma physics
2016, 14(1): 0904002
1 中科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
高功率激光装置中通过测量光束强度分布来评价近场光束质量。然而测量结果为一稳态分布，并不能真实反映经噪声扰动后光束的强弱调制演变特性，可能会忽略传输过程中存在的调制较为严重的区域。针对此问题着重研究了光束经噪声扰动后的近场传输演化特性，进而对近场分布测量的局限性进行深化理解和补充。同时，为简化分析单因素局部缺陷影响下不同传播距离处的近场分布变化规律，引入等效菲涅耳数来表征近场强度调制特性。结果表明，当实测近场分布中存在较弱调制信息时，测量位置之前可能存在更为严重的调制区域。以调制为π的位相型缺陷为例，其最大调制相对于入射光强度可增大9倍。
物理光学 近场光束质量 等效菲涅耳数 表面缺陷
Author Affiliations
Abstract
1 中国科学院上海光学精密机械研究所, 上海 201800
2 中国科学院大学, 北京 100049
For high-power laser facility, sub-beams caused by multiple defects of opitcal component surface with different distributions interfere with each other in the transmission process, bringing about complex changes in beam quality. So it is necessary to make a clear limitation on relative position of defects. On the basis of the diffraction transmission theory, when there are scratches with different spatial distributions on the optical element surfaces, the changes of beam modulation are studied. The influence of scratch depths on the distribution of near field beam modulation is also taken into account. Results show that when two parallel or vertical scratches are on the same or different surfaces of an element. Both of them produce more serious modulation than single scratch, and the maximum modulation degree can be increased to 1.5 times. Meanwhile more strict requirements for scratch depth are put forward. The results can provide reference for the revision of optical element standard and the determination of defects specifications for large- diameter elements in high-power laser systems.
物理光学 相位调制 近场光束质量 表面缺陷 相对位置分布 physical optics phase modulation near filed beam quality surface defect relative position Collection Of theses on high power laser and plasma physics
2015, 13(1): 0308004
