Investigation of multichannel spatial demultiplexer based on thickness-tapered thin film stacks

摘要

A conventional high reflectance (HR) coating sandwiched between two thickness-tapered period thin film stacks is investigated to enhance multichannel spatial dispersion, since phase shift on reflection changes rapidly due to the mismatch induced by the overlaps of different reflective bands. Compared with ordinary Bragg reflector, this structure can be more freely to enhance multichannel spatial shift. The design, fabrication and testing results of this special multichannel filter were presented in the paper, and show the potential to act as a novel demultiplexer.