折返路径光学湍流激光成像探测技术研究
Research on Technique of Fold Pass Laser Imaging and Detection for Atmospheric Optical Turbulence

梅海平吴晓庆饶瑞中

文摘	分析了折返路径光学湍流激光成像探测技术发展的背景和意义,阐述了湍流大气中的折返路径激光传输物理过程及其数学模型。利用构建的实验系统,获取了人造流场和自然湍流场中动态变化的激光散斑回波图像,分析了图像的典型特征.计算表明:利用低通滤波算法可将激光光斑分解成低频的阴影和高频的散斑亮点图像;对相邻的两帧阴影图像进行互相关运算,可以获得二维的横向风场矢量,从而实现湍流场及其中涡旋结构的可视化,同时显示出湍流场在空间上的各向异性。提出了若干有待探究的科学问题,例如如何利用风场矢量提取光学湍流的尺度参数,以及如何利用散斑亮点结合背景纹影技术来分析湍流场结构等,作为下一步的研究目标。
其他语种文摘	The background and meaning of developing the technique of fold pass laser imaging and detection for atmospheric optical turbulence are analyzed, and the physical processes and mathematic models of fold pass laser transmission are represented. Using the constructed experimental system, the echoed dynamic laser speckle images for man-made air flow and natural turbulence flow are obtained. The typical characteristics of the images are described. Calculation of the images with the algorithm of low pass filtering show that the images can be decomposed into low frequency shadows and high frequency bright dots. The mutual correlation of the adjacent shadows can produce the two dimensional vector winds and then visualize the vortexes in the turbulence field. Meanwhile, the anisotropy in the turbulence field can be disclosed. Some scientific problems such as how to extract turbulence scalar parameters from the vector wind, and how to retrieve the structure of optical turbulence from the bright dots in the speckles combined with the principle of background oriented schlieren are proposed, which would be investigated in the next step.
来源	大气与环境光学学报 ,2018,13(6):417-424 【扩展库】
DOI	10.3969/j.issn.1673-6141.2018.06.002
关键词	大气光学湍流 ; 折返路径激光传输 ; 3M反光膜 ; 激光散斑 ; 湍流可视化
地址	中国科学院安徽光学精密机械研究所, 中国科学院大气光学重点实验室, 安徽, 合肥, 230031
语种	中文
文献类型	研究性论文
ISSN	1673-6141
学科	大气科学(气象学)
基金	国家自然科学基金
文献收藏号	CSCD:6374913