无限共轭距物镜的数值孔径全自动测量方法与系统

提出了一种针对无限共轭距显微物镜的数值孔径测量方法,采用载玻片与空气界面处的全反射效应以及其在物镜的后焦面产生的全反射圆作为数值孔径参考基准,根据阿贝正弦定理推导出物镜的数值孔径.完成了基于该原理的实验测试系统的研发,包括光学系统、控制系统和完整的后焦面算法流程.其中的图像处理算法采用了二维傅立叶相关分析和灰度统计.对...

Approach and system for automatic numerical aperture measurementof infinite conjugate objective

Proposes an approach to measure the numerical aperture (NA) of the infinite conjugate objective. It utilizes the total internalreflection (TIR) phenomenon occurring on the air-coverslip interface to generate a reference on the back focal plane (BFP), and theNA is measured based on Abbe sine condition. According to the principle, a home-designed measurement system is developed,containing the optical system, the control system and the whole image-processing software to extract the NA value from experimentallyacquired BFP images. The algorithm of the image-processing software utilizes the two-dimensional Fourier correlation analysis andgrayscale statistics. The NA values of several objective lenses are measured experimentally. The results indicate that the relative error ofthe proposed method is no more than 1% , much lower than that of the other method compared in this work. The proposed methodfeatures on the simple measurement configuration and fast and automatic measurement of the NA of practical oil-immersion objectivelenses. The results show high precision and good repeatability. The approach works for the NA measurement of the infinite conjugate oilimmersion objective lenses.