Schematic of the pinhole array with focal length
f. Lateral central distance L determines wave coupling between the neighboring
holes. The pinholes are uniformly distributed in the
zones. It is illuminated by a plane wave with 633 nm incident wavelength and p-polarization (transverse-magnetic field with
components of , ,
and ). The Ag film has
permittivity ε = at λ 0 = 633 nm. The perfectly matched layer (PML) boundary condition was applied at
the grid boundaries in the 3D FDTD simulation.
