The fields in the focal space of two types of a phase-only diffractive lens
, which is illuminated by a plane wave, are analyzed with the FDTD method a
nd the Stratton-Chu formula. Both oblique and perpendicular incidence are c
onsidered. The diffraction efficiency is calculated. The results of experim
ents carried out to verify the correctness of the calculation are presented
. (C) 2001 John Wiley & Sons, Inc.