基于标准球的显微图像测量系统标定方法  

Micro-Image Measuring System Calibration Based on Standard Ball

作　　者：聂凯[1] 刘文耀[1] 王晋疆[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院,天津300072

出　　处：《纳米技术与精密工程》2013年第2期129-133,共5页Nanotechnology and Precision Engineering

基　　金：国家高技术研究发展计划(863计划)资助项目

摘　　要：提出一种利用标准球对显微图像测量系统进行标定的方法.该方法利用显微系统小视场小景深的成像特点简化计算模型,减少标定参数.通过标准球图像在水平和垂直方向上的直径比计算比例因子;利用标准球边缘图像的边缘点集,运用优化的方法来计算成像系统的畸变系数和主点位置.系统的放大倍数由标准球的实际直径来标定得出.利用标准球在多摄像机公共视场内其轮廓在任何位置均可见这一特性,可同时对显微图像测量系统中的多个摄像机进行标定,简化标定过程.实验结果表明,该方法标定精度较高,标定后的测量系统的极限误差3σ为2.41μm.A camera calibration method using standard ball is proposed for micro-image measuring sys- tem that has small field of view and small depth of field. The method simplified the computational mod- eling and reduced calibration parameters. The scale factor can be calculated by means of the ratio of horizontal diameter to vertical diameter of the image of standard ball. According to the point set of sil- houettes of standard ball, the distortion coefficient and the position of principal point of imaging system can be calculated by optimization method. The magnification of micro imaging system can be figured out based on the actual diameter of standard ball. Using the feature that the contours of standard ball placed in the common field of view of multiple cameras are always visible from any position, multiple cameras in micro imaging system can be calibrated simultaneously, so the process of calibration will be simplified. The experimental results show that calibration precision is high and the limit error, 3σ, of the system calibrated by this method is 2.41μm.

关 键 词：显微测量 摄像机标定 标准球 图像处理 多摄像机 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]