A silicon based Fourier transform spectrometer base on an open-loop controlled electrothermal MEMS mirror

This paper reports a compact Fourier transform spectrometer system with a large-stroke electrothermal MEMS mirror and other optical components all integrated on a micro-machined silicon base with the dimension of 2cm×2cm. The overall size of the system is reduced dramatically from the prior work [1]. The linear optical path difference (OPD) scan range is increased to 440μm and the mirror plate tilting is compensated down to ±0.002° during the full OPD scan using a new open-loop control method. A spectral resolution of 1.1nm at 532nm is achieved.