光镊中油浸物镜数值孔径利用率的研究  

The Numerical Aperture Utilization Ratio of Oil-immersion Objective in Optical Tweezers

作　　者：谷勇强[1] 龚錾[1] 楼立人[1] 李银妹[1] 

机构地区：[1]中国科学技术大学物理系

出　　处：《应用激光》2007年第2期98-103,共6页Applied Laser

摘　　要：本文利用光线光学模型,对使用高数值孔径的油浸物镜时,由于折射率的不匹配引起球差,导致光阱捕获力下降的物理原因进行了分析,引进了数值孔径利用率这一参数,并给出了具体计算公式。进而在不同条件下进行了数值计算,给出了数值孔径的利用率与光阱纵向刚度系数的依赖关系。The propagation of light in a typical optical tweezers, where a high-NA oil-immersion objective is used, is analyzed by the ray optics approximation. It is concluded that the spherical aberration due to the index mismatch causes trapping force decreasing can be attributed mainly to the fact that part of rays do not pass through the particle, which can be properly described by introducing a parameter of the numerical aperture utilization ratio. The expression for calculating the ratio is derived. Then the numerical aperture utilization ratio and the longitudinal trap stiffness coefficient are numerically analyzed in different conditions to demonstrate the parallel relation between the newly introduced parameter and the trapping efficiency.

关 键 词：光镊 RO模型 数值孔径利用率 

分 类 号：O241[理学—计算数学]