Depolarization of quasi-monochromatic light by thin resonant gratings

Using rigorous diffraction theory, we show that it is possible to depolarize quasi-monochromatic light using a fully deterministic, thin optical element. The principle is based on polarization-sensitive resonant gratings in total-internal-reflection configuration, and careful numerical design by the Fourier modal method. We present numerical examples for 0.1 ran and 10 nm bandwidths. (C) 2009 Optical Society of America