In this paper, we present an efficient effective permittivity treatment for the two-dimensional Finite-
Difference Time-Domain (2D-FDTD) method that can be applied to dielectric interfaces. Various
issues related to simulation arrangements are discussed based on the 60 photonic crystal (PhC)
waveguide bend as a test case. The transmission, obtained numerically, agrees very well with
other two-dimensional simulation methods, namely the finite-element method (2D-FEM) and the 2D
multiple multipole program (2D-MMP). Compared to other FDTD schemes, such as staircasing and
the volume averaging method, our model performs faster and provides more accurate results for
the dielectric interface.