A spectral collocation multi-domain scheme is developed for the accurate an
d efficient time-domain solution of Maxwell's equations within multi-layere
d diffractive optical elements. Special attention is being paid to the mode
ling of out-of-plane waveguide couplers. Emphasis is given to the proper co
nstruction of high-order schemes with the ability to handle very general pr
oblems of considerable geometric and material complexity. Central questions
regarding efficient absorbing boundary conditions and time-stepping issues
are also addressed. The efficacy of the overall scheme for the time-domain
modeling of electrically large, and computationally challenging, problems
is illustrated by solving a number of plane as well as non-plane waveguide
problems. (C) 1999 Academic Press.