为了修正显微镜点扩散函数荧光微球传统测量方法中微球直径对测量结果的影响、提高显微镜点扩散函数的测量精度, 采用理论仿真、最小二乘拟合的方法, 建立荧光微球等效2维浓度分布, 模拟仿真了荧光微球显微成像过程; 利用最小二乘拟合以及残差拟合的方法, 得到荧光微球直径、荧光微球强度分布半峰全宽与系统实际点扩散函数半峰全宽之间的关系模型, 由此模型得到较为准确的系统点扩散函数半峰全宽。结果表明, 使用100nm荧光微球对系统点扩散函数进行测量时, 相对误差在1%左右。此研究结果说明通过该修正模型可以得到较为准确的系统点扩散函数。

In order to eliminate effect of fluorescent bead diameter on measurement results in traditional microscopic point spread function measurement method and improve the measurement accuracy, 2-D equivalent concentration distribution of fluorescent beads was deduced based on theoretical simulation and least square fitting method. The imaging process of fluorescent beads was simulated. The relationships among fluorescent beads diameter, full width at half maximum (FWHM) of fluorescent beads intensity distribution and FWHM of system point spread function were analyzed by using the least square fitting method and residual error fitting method. Precise FWHM correction model of point spread function was obtained. The results show that the relative error of point spread function FWHM is about 1% when measuring system point spread function with 100nm fluorescent beads. The precise measurement of point spread function is realizable with the optimized model.