平面标定法在闪电光学观测中的应用  

APPLICATION OF PLANE CALIBRATION METHOD IN OPTICAL OBSERVATION OF LIGHTNING

作　　者：谢正帅 吕伟涛[1] 马颖[1] 齐奇[1] 武斌 姜睿娇 孙秀斌[2] 陈绿文[3] 杜赛 颜旭[3] 肖桐 XIE Zhengshuai;LYU Weitao;MA Ying;QI Qi;WU Bin;JIANG Ruijiao;SUN Xiubin;CHEN Lyuwen;DU Sai;YAN Xu;XIAO Tong(State Key Laboratory of Severe Weather/Laboratory of Lightning Physics and Protection Engineering,Chinese Academy of Meteorological Sciences,Beijing 100081,China;Chengdu University of Information Technology,Chengdu 610225,China;Guangzhou Institute of Tropical and Marine Meteorology,CMA,Guangzhou 510641,China;Institute of Communication and Signaling,China Academy of Railway Sciences Group Co.,Ltd.,Beijing 100081,China)

机构地区：[1]中国气象科学研究院灾害天气国家重点实验室/雷电物理和防护工程实验室,北京100081 [2]成都信息工程大学,四川成都610225 [3]中国气象局广州热带海洋气象研究所,广东广州510641 [4]中国铁道科学研究院集团有限公司通信信号研究所,北京100081

出　　处：《热带气象学报》2022年第3期444-452,共9页Journal of Tropical Meteorology

基　　金：国家重点研究发展计划(2017YFC1501504);国家自然科学基金项目(42175108);中国气象科学研究院基本科研业务费专项(2021Z011);中国铁道科学研究院集团有限公司院基金课题(2020YJ171)共同资助。

摘　　要：针对闪电光学观测资料定量分析的需求,采用张正友平面标定法结合便携式平面靶标,实现了闪电外场试验中光学观测设备的现场标定,为消除光学系统成像畸变对闪电通道特征分析的影响提供了一种便捷的途径。使用此方法对广州高建筑物雷电观测站(TOLOG)的6套闪电光学观测设备进行了标定,结果表明:光学观测设备搭载同类型镜头时,焦距越短图像的畸变越明显;图像中视线与光轴的夹角越大,径向畸变的影响越明显,采用鱼眼镜头获得的闪电通道图像在靠近边缘的位置畸变的影响会超过25%;通过对配备焦距为8mm鱼眼镜头的单反相机以及配备焦距为8 mm广角镜头的高速摄像机同时获取的闪电光学同步资料进行畸变校正后,发现获取的图像畸变校正前后闪电通道总体长度差异分别为12.9%和4.5%;经过畸变校正后不同设备获取的闪电通道图像比原图拥有更好的一致性。This study is aimed to quantitatively analyze the observational data of various optical equipment at the observation station of the Tall-Object Lightning Observatory in Guangzhou(TOLOG),and also realize the on-site calibration of the lightning optical observation equipment in field tests.We adopted the plane calibration method and calibrated the six types of lightning optical observation equipment using a portable plane calibration target.The results showed that the shorter the focal length of the lens,the greater the distortion coefficient.In the image,the influence of radial distortion was also positively associated with the angle between the line of sight and the optical axis.The distortion of the edge of the lightning channel captured by fish eye lens would be more than 25%.After performing distortion correction on the lightning optical data collected by the Nikon SLR D7100 camera equipped with a Nikon8 mm fisheye lens and a high-speed camera equipped with a Computar 8 mm wide-angle lens,we found that the total length of the lightning channel before and after image distortion correction differed by12.89% and 4.45%,respectively.It showed that the distortion caused by the focal length and the type of lens had different effects on the lightning channel image.After distortion correction,however,the shape and length of the lightning channel obtained by different optical devices had a good consistency.This research provides a convenient method to eliminate the influence of optical system imaging distortion on the analysis of lightning channel characteristics.

关 键 词：摄像机标定 平面靶标 畸变校正 闪电光学观测 

分 类 号：P427.3[天文地球—大气科学及气象学]