光斑质心亚像素定位误差的实验研究

Experiment Research on Subpixel Location Error of the Facula Centroid

根据误差的来源将光斑质心亚像素定位误差归类为随机误差和系统误差,提出一种简单有效的实验方法对光斑质心定位误差进行定量测试。利用高精度一维电动平移台、POINTGREYFlea2-14S3CCD相机和LED光源构建了测试系统,对测试结果进行研究和讨论,发现了测试系统LED光斑质心定位系统误差的周期性变化规律,计算得到了基于Flea2-14S3CCD相机的光斑质心定位随机误差为0.018pixels,系统误差为0.06pixels,总体误差为0.063pixels(约1/15pixels),能够应用于以光斑质心检测为手段的测量系统中。实验表明,该测试系统可以作为估算光斑质心定位误差大小的一种有效的手段。

According to the resource of error, the subpixel location error of the facula centroid has been classified as random error and system error. A simple and effective method is proposed to measure the location error of facula centroid. A measuring system which mainly consists of a high precision motorized translation stage of one dimension, POINT GREY Flea2-14S3 CCD camera and LED light source was designed and constructed. Based on a detailed analysis for experiment results, the periodic changing law of system error of LED facula centroid location in this measuring system was found. The results indicate that based on Flea2-14S3 CCD camera, the random error of facula centroid location is about 0.018 pixels, the system error is about 0.06 pixels, and the total error is about 0.063 pixels （1/15 pixels）. According to the total error above, this CCD imager can be widely used in many measuring systems which count on facula centroid subpixel detection. The experiment shows that the measuring system is an effective means to estimate the location error of facula centroid