Multispectral Imaging with Tunable Plasmonic Filters

We present an angle-insensitive, miniaturized and integratable filtering system based on plasmonic substrates for multispectral imaging. Active tunability of the plasmonic filter allows color recording, estimation of unknown spectra, and determination of spectral singularities, for example, laser lines, while exploiting the full spatial resolution of a B/W conventional camera. Compared to other multispectral imaging systems, the plasmonic filtering system can be placed in front of an existing imaging system, for example, including lenses, supporting a cost-efficient fabrication and integration. Additionally, it is characterized by high angular acceptance, which we demonstrate by imaging with a field-of-view of'-50. Further, the number of nonpixelated broadband filters could be varied in situ for faster imaging or higher quality, compared to systems with a fixed number of channels.