QQ客服 官方微博 反馈留言

题名	皮秒激光终端测量的关键准直技术研究
作者	闫世森
文献子类	硕士
导师	刘代中
关键词	高功率激光装置 High power laser 参数测量 alignment design 准直设计 measurement control 图像处理 image analysis
其他题名	Research on key alignment technology of picosecond laser terminal measurement
英文摘要	皮秒激光终端测量是高功率激光装置的重要组成部分，它用来实现相关激光参数的获取与分析，并同时为物理实验提供可靠、有效的实验数据，如能量、脉宽、远场、信噪比等。由于皮秒激光终端测量系统光路复杂，元件庞杂，测量系统的仪器设备，如新型的信噪比测量仪，对系统的近、远场稳定性要求较高。为了保证装置的正常运行，皮秒激光终端测量系统对光束的近场和远场的准直精度有着较高的要求。 本文基于皮秒激光终端测量系统，专注于反馈控制、图像处理与测量分析等关键准直技术的研究和发展。主要实现了皮秒激光终端测量系统在光路、算法、软硬件方面的优化。通过设计新型的准直光路和优化算法，提升了皮秒激光终端测量系统的集成化、智能化，并实现了快速、高效的准直控制。 本论文的主要研究内容如下所述： 1. 基于皮秒测量平台的立体光路，设计出立体光路快速准直方案。在高功率激光参数中，获取单脉冲信噪比参数是一项重要任务。而单脉冲信噪比测量仪在使用过程中对输入光束的偏振状态有具体要求。为了满足单脉冲测量仪对输入的要求，设计了立体空间激光光路实现偏振态的偏转。然而立体空间光路会导致电机驱动反射镜时，光斑移动方向与轴向方向不同，导致传统的多次迭代逼近算法无法实现准直要求。为了解决立体空间光路准直方法的空缺，设计了一种基于线性矩阵理论的快速准直方法。该方法仅要求系统为线性系统，对电机驱动反射镜时光斑移动的方向不敏感。通过在线联机实验证明，该准直方法在φ40mm大小光斑图像下可实现激光近场对准精度小于0.3mm，远场对准精度小于0.16mrad。 2. 利用准直远场探测包和光栅元件的双向衍射，实现了空间滤波器的小孔准直，特别是对同一段光路中的两个空间滤波器的小孔对准。该方案克服了传统滤波器小孔对准方法中的不足：准直过程中滤波器小孔硬件本身存在约束。在实现光路远场准直的同时，实现了小孔中心位置的准直调整与监测。实验结果表明，小孔准直精度小于小孔直径3%，满足了高功率激光装置滤波器小孔的总体准直要求(小于小孔直径的4%)。 3. 基于LabVIEW的测量准直控制软件的研发。通过对LabVIEW平台的介绍，提出一种基于LabVIEW平台应用于皮秒激光装置测量和准直控制的集成软件。通过LabVIEW开发平台实现近、远场图像采集，马达控制和快速自动准直等功能，并针对测量近、远场的图像进行伪彩色显示、三维显示与环围能量能等参数计算分析。该集成软件初步实现了终端测量与准直控制的部分功能，增加了系统集成度与智能度。 4. 设计了满足高功率激光多状态输出的通道切换准直单元。由于神光II高功率激光装置有大、小能量两种主要的输出状态，对测量系统提出了两种测量需求。通过通道切换准直单元实现了大能量输出状态和小能量输出状态的自动切换，提供了实时的近、远场监测，保证了双通道切换的准确性和高效性，完成不同状态的测量需求，满足了皮秒参数测量平台对切换精度的要求。; Picosecond laser terminal measurement is an important part of inertial confinement fusion (ICF). It is used to achieve the acquisition and analysis of relevant laser parameters, and at the same time provide reliable and effective data for physical experiments, such as energy, pulse width, far field, signal-to-noise ratio(SNR) and so on. Because the high-power laser system has complex optical path and complex components, the optical path transmission process is different. In order to ensure the normal and effective operation of the device, there is a high requirement on the alignment accuracy of the near-field and far-field of the beam for the picosecond laser terminal measurement system. Based on picosecond laser terminal measurement system, this paper focuses on feedback control, measurement analysis and image processing. It mainly realizes optical path, algorithm, software and hardware optimization in picosecond laser terminal measurement system. Through the design of the new alignment optical path and optimization algorithm, the integration and the intelligent of the picosecond laser terminal measurement system are enhanced. The main contents of this paper are as follows: 1. The monopulse diagnosis is realized by stereoscopic optical path, and designing a matching method of stereoscopic optical alignment. In the picosecond parameter measurement platform, monopulse signal-to-noise ratio measurement is an important part. The monopulse measuring instrument has specific requirements for the polarization state of the input beam. In order to meet the requirements of monopulse measuring instrument, a space stereoscopic laser beam is designed to realize polarization state deflection. However, when the stereoscopic optical path leads to the motor driven reflector, the direction of the spot movement is different from the axial direction, which causes the traditional iterative approximation algorithm to be unable to achieve the alignment requirements. A fast alignment method based on linear theory is designed to solve the vacancy of stereoscopic spatial optical alignment. The method does not depend on the condition that the motor adjusts the same direction as the axis. Through on-line experiments, it is proved that the alignment method can achieve near field accuracy less than 0.3mm and far-field accuracy less than 0.16mrad. 2. The alignment of pinholes in spatial filters is realized by grating diffraction. By using the bidirectional diffraction of the grating element, the pinhole alignment of the spatial filter is realized, especially for the pinhole alignment of the two spatial filters in the same section of optical path. The scheme overcomes the shortcomings of the traditional filter pinhole alignment method: the limitation on the size of the pinhole and the high stability of the far field alignment package. The scheme is applied to the device in the cooperative project. The result shows that the precision of the pinhole alignment is less than 3% of the diameter of the pinhole, which satisfies the alignment requirement of the pinhole of the device (< 4% of the pinhole diameter). 3. Research and development of measurement alignment control software based on LabVIEW. Through the introduction of the LabVIEW platform, an integrated software based on LabVIEW suitable for measurement and alignment control of picosecond laser devices is proposed. Through LabVIEW platform, the functions of near and far field image acquisition, motor control and rapid automatic alignment can be realized. The parameters of pseudo color display, 3D display and ring circumference energy can be calculated and analyzed for the near and far field images. The integrated software has initially implemented some functions of terminal measurement and alignment control, and increased system integration and intelligence. 4. A channel switching alignment unit for high power laser multi state output is designed. Because of the two main output states of the high power laser device, two measurement requirements are put forward for the measurement system. Through dual channel alignment unit, the switching state of large energy output and the state of small energy output are realized, and the measurement needs of different states are completed. At the same time, it is designed to meet the requirements of beam energy and beam diameter after the channel switching. The accuracy of the picosecond parameter measurement platform is satisfied.
学科主题	光学工程
内容类型	学位论文
源URL	[http://ir.siom.ac.cn/handle/181231/31073]
专题	中国科学院上海光学精密机械研究所
作者单位	中国科学院上海光学精密机械研究所
推荐引用方式 GB/T 7714	闫世森. 皮秒激光终端测量的关键准直技术研究[D].

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。