Design of polarization insensitive narrow bandpass filter

摘要

An infrared narrow bandpass filter of single half-wave cavity was designed at non-normal incidence ofradiation illuminatedrnby collimated energy within the spectral region (8→12μm). The change in the spectral characteristic of the filter was studied with the aid of characteristic matrix theory. Further more, needle optimization method was used to provide the best conformance to desire spectral characteristic at the operating conditions of an infrared system, thus, polarization insensitive narrow bandpass was achieved.