光镊模型的矢量衍射矩阵化方法与应用研究

The Study on Method and Application about the Vector Diffraction Matrix of Optical Tweezers

光镊是生物物理以及生物工程领域的一种重要工具,光镊模型及其求解是目前的一个研究重点。根据矢量散射的基本原理和米氏散射作用,提出了一种将矢量衍射方程矩阵化的方法,该方法把经过透镜汇聚的入射光束进行平面波分解,结合米氏散射公式与旋转变换,然后导出了散射光场的矩阵形式,最后将该矩阵应用于模拟计算米氏散射的光场。此方法不限制光束的波长,不但简化了运算难度,也获得了与无散射情况下的矢量衍射计算、有散射情况下的瑞利近似计算各自相同的结果。本文的研究方法可应用于具有一定大小粒子的散射计算,为进一步控制光镊行为提供了依据。

Optical tweezers are an important tool in biophysical and bioengineering fields which model and solution are the main research points recently. According to the basic principle of vector scattering and Mie scattering effect,a vec-tor diffraction equation matrix method is proposed in this paper where a plane wave decomposition is done after it went through the lens and is combined with Mie scattering formula and rotation transform. Finally the matrix was applied to simulation of the Mie scattering field. This method does not restrict the wavelength of the light beam. It does not only simplify the calculation difficulty , but also get the same vector diffraction calculation results as other two methods including of the vector diffraction calculation without and with Rayleigh approximation. The research method can be ap-plied to the scattering calculation of particles with a certain size , which provides a basis for further controlling the behavior of optical tweezers.