Design of an integrated wide-angle, broad polarization band pass filter

A wide-field-of-view broad-band spectral filter with polarization function is presented for skylight polarization detection. The designed structure consists of a nanowire grating and a multilayer dielectric band pass filter. The simulation based on the rigorous coupled wave analysis shows that with the optimized uppermost layer of the dielectric filter or the addition of the PMMA layer, the desired integration performance can be achieved. The grating parameters are thoroughly investigated using rigorous coupled wave analysis and effective medium theory. The TM transmission higher than 80% and the extinction over 500 can be achieved in the range of 380nm to 520nm, up to ±35° wide incident angle, and extremely low transmission for both TM and TE polarization in the other spectral range are also obtained.