Low-SWaP Solutions for Adaptive Multi-Spectral Infrared Imaging

This paper presents a review of work undertaken within the Microelectronics Research Group at the University of Western Australia towards realizing adaptive optical filters for multispectral infrared imaging applications. While much of this work has focused on the shortwave infrared bands due to commercial interests, some progress in other bands will also be presented. This work builds on the microelectromechanical systems (MEMS)-based infrared spectrometer technology, developed by the Microelectronics Research Group, as the underlying foundation of tunable infrared filters for adaptive multispectral infrared imaging systems. This paper will consider the development of large-area MEMS Fabry-Perot filters for imaging, examining the key imaging considerations as well as key device considerations. These considerations will dictate operational limits, device-level design choices, and system-level design choices. Finally, results from recent projects are presented, including a hybrid vision/spectroscopy solution for low-cost small autonomous platforms, as well as large-area MEMS tunable filters for fully adaptive multispectral infrared imaging. The work on large-area MEMS tunable filters includes linear centimetre-scale filter devices for the short-wave infrared (SWIR), multi-millimetre-scale tunable devices for the mid-wave infrared (MWIR), and a proof-of concept multi-millimetre-scale filter device for the long-wave infrared (LWIR) band.