摘要
采用Matlab语言进行仿真并对Mie理论中消光率(归一化消光截面)的数学性质进行理论分析与数值计算,讨论了消光率曲线的波纹结构与尺寸参数x的关系以及波纹结构的峰值与Mie散射振幅an(x,m)、bn(x,m)的对应关系。研究了消光率曲线波纹结构的近似周期与相对折射率m的关系,并给出了计算机仿真运行结果。结果表明,消光率随x的变化曲线具有波纹结构,当相对折射率m增大时,这一现象变得不明显;当m为实数,且m≤2时,消光率曲线的波纹结构具有单一周期性,并且波纹结构的峰值出现的位置与Re[an(x,m)]、Re[bn(x,m)]的峰值出现的位置相对应;当m为复数时,只要满足|Im(m)|<0.01,波纹结构仍具有相同的近似周期,只是振荡的振幅减小了,|Im(m)|越大,波纹结构的振荡振幅越小。计算机仿真结果可为微球体光学性质的研究提供参考。
The mathematical character of the extinction efficiency (normalized extinction cross section) is analysed and the numerical computation by Matlab language computer simulation is studied. The relationships between the ripple structure of the extinction efficiency and the size parameter x, the peak value of the ripple structure and the amplitude of Mie scattering an(x, m), bn (x, m) are discussed. The relationship between the approximate periodicity of the ripple structure and relative refractive index m is also discussed. The result shows that the relation curve of the extinction efficiency and the size parameter x has ripple structure, which becomes faint as x is large; when the relative index m is real and m≤2, the ripple structure has single periodicity, and positions of the peak values of the ripple structure are corresponding to the positions of peak values of Re[an(x, m)] and Re[bn (x, m)]. When m is complex and |Im(m)|<0. 01, the ripple structure also has the same periodicity, however, the oscillation amplitude of the ripple structure becomes weaker. The larger |Im(m) | is, the weaker the oscillation amplitude of the ripple structure is. The computer simulation results of this paper can provide reference for further study of microsphere.
出处
《红外与激光工程》
EI
CSCD
北大核心
2004年第3期231-234,共4页
Infrared and Laser Engineering
关键词
计算机仿真模拟
MIE理论
光散射
消光率
Computational methods
Computer programming languages
Computer simulation
Graph theory
Light scattering
Oscillations
Refractive index
