Analytical approximation of optical force on a perfectly reflecting sphere: ray-optics regime

  • Kim, Sang Bok (Department of Environmental Machinery, Environment System Research Division Korea Institute of Machinery and Materials) ;
  • Song, Dong Keun (Department of Environmental Machinery, Environment System Research Division Korea Institute of Machinery and Materials)
  • Received : 2018.03.16
  • Accepted : 2018.03.23
  • Published : 2018.03.31


The optical force on a perfectly reflecting sphere in a ray-optics regime is considered. With the assumption of geometric optics and a sphere smaller than the minimum waist of the illuminating beam, closed-form analytic expressions of the optical force are derived. Both axial and radial forces are expressed by a modified Bessel function of the first kind. The derived analytic expressions are compared to precise numerical computations of the exact optical force equations derived previously. In addition the error due to the small sphere assumption is estimated analytically.


Supported by : Korea Institute of Machinery and Materials


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