Advanced MEMS/Smart-Material Coding and Filtering Technologies for High-Performance Miniature Integrated IR Spectrometers

Abstract

Infrared spectroscopy can be a vital component of various Earth observation and planetary exploration space missions. It probes the characteristic vibrational modes of chemical bonds in molecules to provide information about not only the chemical composition but also the local bonding configuration and environment of the chemical bond. The IR spectral technique can be used with minimal consumables to simultaneously detect large variety of chemical and biochemical species. To date, mainly large bulk-optic Fourier Transform (FT-IR) spectrometers employing variations of the Michelson interferometer have been successfully employed in space due to the attainable performance. However, they typically require costly, large spacecraft platforms and complex environmental controls that limit the deployment of IR spectroscopy. In the following paper, we discuss the use of advanced optical coding and signal processing techniques, as facilitated using MEMS multi-channel optical signal processors, to significantly extend the performance limitations of miniature integrated-optic IR spectrometers. This technology can provide high-performance broad-band IR spectrometers suitable for passive monitoring in a compact module weighing under 2 kg.