Preston Thomas C, Reid Jonathan P
J Opt Soc Am A Opt Image Sci Vis. 2015 Nov 1;32(11):2210-7. doi: 10.1364/JOSAA.32.002210.
A new method for determining the radius and refractive index of microspheres using Mie resonances is presented. Previous methods have relied on searching multidimensional space to find the radius and refractive index that minimize the difference between observed and calculated Mie resonances. For anything but simple refractive index functions, this process can be very time consuming. Here, we demonstrate that once the mode assignment for the observed Mie resonances is known, no search is necessary, and the radius and refractive index of best-fit can be found immediately. This superior and faster way to characterize microspheres using Mie resonances should supplant previous fitting algorithms. The derivation and implementation of the equations that give the parameters of best-fit are shown and discussed. Testing is performed on systems of physical interest, and the effect of noise on measured peak positions is investigated.
提出了一种利用米氏共振确定微球半径和折射率的新方法。以往的方法依赖于在多维空间中搜索，以找到使观测到的和计算出的米氏共振之间的差异最小化的半径和折射率。对于除简单折射率函数之外的任何情况，这个过程可能非常耗时。在这里，我们证明，一旦知道了观测到的米氏共振的模式分配，就无需搜索，并且可以立即找到最佳拟合的半径和折射率。这种利用米氏共振表征微球的更优越、更快的方法应该会取代以前的拟合算法。展示并讨论了给出最佳拟合参数的方程的推导和实现。对具有实际物理意义的系统进行了测试，并研究了噪声对测量峰值位置的影响。
