摘要
在高精度尺寸测量系统中,采用传统短焦距定焦光学方法时径向畸变较大,影响测量精度。为提高测量的精度,根据摄像机针孔成像的线性模型和镜头的非线性模型,建立摄像机定焦镜头的对焦数学模型,提出了采用交比不变的标定方法。研究了物体远近的小范围变化对测量结果准确度的影响,修正了标定的像素当量;分析了镜头的几何投影变换关系,标定了镜头的畸变系数,达到高精度测量目的。实验数据表明,提出的标定算法与结果一致。
In high-precision .size measurement system, the traditional method using short-focus fixed focal length lens has large radial distortion that may affect the measurement accuracy. In order to improve the accuracy of the measurement system, a focusing model of fixed-focus lens of camera was established and cross- ratio invariant calibration method was proposed according to the linear imaging model of pinhole camera and the non-linear model of lens. The impact of small objective distance changes on measurement accuracy was studied, and the calibrated pixel equivalent coefficient was revised. The geometric projective transformation of lens was analyzed, and the distortion coefficients of lens were calibrated for realizing high-precision measurement. The experiment showed that the proposed algorithm is consistent with the result.
出处
《电光与控制》
北大核心
2011年第2期93-96,共4页
Electronics Optics & Control
基金
陕西省教育厅产业化项目基金(03JC29)
关键词
相机标定
调焦模型
高精度
交比不变性
camera calibration
focusing model
high precision
cross-ratio invariance
