A fast MEMS infrared microspectrometer for the measurement of hydrocarbon gases

Abstract

A new fast infrared microspectrometer based on a MEMS tunable Fabry-Pérot filter (µFPF) is reported. In contrast to previous designs the acquisition time for a complete spectrum is decreased 50 times and the spectral resolution is improved 3 times. This is achieved by the use of higher interference orders and the combination with a room temperature operated PbSe photodetector. Such a system will be especially useful for the measurement of hydrocarbon gases in the spectral range of (3.1…3.8) µm. The µFPF is tuned sinusoidally over the entire wavelength range in about 100 ms. Methods for offset elimination and drift compensation were developed as well.