This paper addresses the similarity of microwave/millimeter wave frequency selective surfaces (FSS) to optical filters. Specifically, the design approaches of the 4-band FSSs developed for NASA's CASSINI high gain antenna are described in detail. Representative RF test results are given to demonstrate the validity of these designs. These design approaches are very general and can be applied to multiband optical filters.
"Multiband frequency selective surface", Proc. SPIE 3464, Optical Devices and Methods for Microwave/Millimeter-Wave and Frontier Applications, (2 October 1998); doi: 10.1117/12.323140; https://doi.org/10.1117/12.323140