Compact designs of hyper- or multi-spectral imagers compatible with the detector dewar

We have recently shown that dewar-level integration of optics is a promising way to develop compact IR cameras. Indeed, the integration of optics into the dewar leads to simple and entirely cooled optical architectures dedicated to imaging applications with large-field of view. Here, we review the optical elements we could add in those devices to make a hyper- or multispectral imager. Among them, we find specific focal-plane arrays with a built-in spectrometry function, plasmonic filters combined with a multichannel optical design, and birefringent interferometers. Several optical architectures will be detailed with first experimental results.