MEMS-based compact FT-spectrometers - a platform for spectroscopic mid-infrared sensors

Abstract

Novel low-voltage driven translational MEMS micro-mirror components are used to build a fully portable Fourier-Transform spectrometer. Applying nearly inertia-less MEMS devices to modulate the IR light allows building highly compact spectrometers with sub-millisecond scan times that are immune to shock and vibrations. Compact, energy efficient and robust, MEMS-based spectrometers can thus act as transducers for spectroscopic IR sensors deployable in the field. The devices shown can be used to qualitatively and quantitatively measure absorbance and/or emission spectra, even of transient signals and in real time, over a wide spectral range. This allows making full use of the inherent multi-analyte detection capabilities of spectroscopic sensors, giving this spectroscopy platform a significant advantage over single-wavelength IR sensors. When combined with already available fibre-optic sensor probes, the resulting sensors could open new application fields for smart sensors.

Position encoding and phase control of resonant MOEMS mirrors

“…We expect our results to provide significant impact for applications of these MOEMS mirrors e.g. in compact projection devices and MEMS-based spectrometers [16].…”

MOEMS translatory actuator characterisation, position encoding and closed-loop control

“…Based on these, prototypes of a compact Michelsontype FT-spectrometer have been developed (Kenda et al 2006) and tested. The resulting compact instrument has successfully been used to measure mid-infrared absorptions and emissions at time resolutions in the millisecond range (Kraft et al 2008;Kenda et al 2009). …”

Continuous Monitoring of Air Purification: A Study on Volatile Organic Compounds in a Gas Cell

“…The use of a multi-pass gas cells with the MEMS FTIR spectrometer and high brightness light source has been reported for improving the detection limits [27]. In [28], a FTIR spectrometer based on using a translation MEMS mirror with other discrete optical components was used to measure propane and butane using a path length of 6 cm. Gas measurement was performed using a MEMS lamellar grating FTIR spectrometer in [29].…”