Implementing the near- to far-field transformation in the finite-difference time-domain method. Academic Article uri icon

abstract

  • When the finite-difference time-domain (FDTD) method is applied to light-scattering computations, the far fields can be obtained by means of integrating the near fields either over the volume bounded by the particle's surface or on a regular surface encompassing the scatterer. For light scattering by a sphere, the accurate near-field components on the FDTD-staggered meshes can be computed from the rigorous Lorenz-Mie theory. We investigate the errors associated with these near- to far-field transform methods for a canonical scattering problem associated with spheres. For a scatterer with a small refractive index, the surface-integral approach is more accurate than its volume counterpart for computation of the phase functions and extinction efficiencies; however, the volume-integral approach is more accurate for computation of other scattering matrix elements, such as P12, P32, and P43, especially for backscattering. If a large refractive index is involved, the results computed from the volume-integration method become less accurate, whereas the surface method still retains the same order of accuracy as in the situation for the small refractive index.

published proceedings

  • Appl Opt

author list (cited authors)

  • Zhai, P., Lee, Y., Kattawar, G. W., & Yang, P.

citation count

  • 18

complete list of authors

  • Zhai, Peng-Wang||Lee, Yong-Keun||Kattawar, George W||Yang, Ping

publication date

  • June 2004