摘要
在空间大口径追踪相机应用系统中,像面畸变和主点主距标定误差是影响其在轨定位精度的重要因素。为了满足空间大口径追踪相机高精度的标定要求,像面畸变类型、主点主距标定误差及探测器面阵旋转、倾斜对像点坐标带来的误差等因素均不可忽略。针对以上问题,本文对该类系统的畸变特性进行了研究,提出了一种改进的大口径追踪相机畸变校正方法。首先,在视场中央无畸变区域测量13个样点,根据最小二乘法获取光学系统的主点主距;然后,依据所求主点主距,解算像面25个均匀分布样点的理论位置坐标;最后,由样点的理论坐标和测量坐标解算畸变模型,实现畸变校正。实验结果表明,该方法畸变校正精度在近红外波段优于0.32 pixel,在短波红外波段优于0.28 pixel,其相对传统畸变校正模型分别提高了44.6%和50.9%。该方法可为大口径追踪相机的焦平面倾角解算研究提供有益参考。
In the context of applications of spatial large aperture tracking cameras, calibration errors of the principal point and distance and associated distortions are considered to be important issues in the problem of on-obit geometric positioning. To meet the high-precision calibration demands on spatial large-aperture tracking cameras, factors of the distortion types, calibration errors of the principal point and distance, as well as rotation and inclination of the detector array, must all be addressed. To solve these problems, this paper analyzes distortion characteristics of systems of this type and proposes an improved distortion correction method for large aperture tracking cameras. First, the optical principal point and distance are ascertained using 13 points on the small central area of the focal plane via the least square method. Following that, the theoretical coordinates of the 25 test points distributed uniformly on the focal plane are calculated with the help of the recently acquired principal point and distance. Finally, the parameters of the distortion model are estimated using the theoretical coordinates and the measured coordinates of the test points, and the distortions of the camera are corrected. Experimental results showed that even distortion errors of less than 0.32 pixels and 0.28 pixels were corrected by the proposed method in a near-infrared image and a short-wavelength infrared image, respectively. Thus, the distortion correction is 44.6% and 50.9% better than that of conventional distortion models. Thus, the proposed method provides a beneficial reference in the research concerning the obliquity of the focal plane of large aperture tracking cameras.
作者
蔡萍
李潇雁
唐玉俊
张勇
胡亭亮
陈凡胜
CAI Ping;LI Xiao-yan;TANG Yu-jun;ZHANG Yong;HU Ting-liang;CHEN Fan-sheng(Key Laboratory of Intelligent Infrared Perception, Chinese Academy of Sciences, Shanghai 200083, China;University of Chinese Academy of Sciences, Beijing 100049, China)
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2019年第10期2272-2279,共8页
Optics and Precision Engineering
基金
国家自然科学基金资助项目（No.61975222）
关键词
大口径追踪相机
畸变校正
畸变模型
large aperture tracking cameras
distortion correction
distortion models
