MEMS-based miniature near-infrared spectrometer for application in environmental and food monitoring

Abstract

We present a hybrid MEMS (micro-electromechanical systems) based spectrometer of the size of a sugar cube, fabricated at the clean room facilities of Fraunhofer IPMS, Dresden. This SGS (scanning grating spectrometer) is designed for integrated spectroscopic applications in the field of food quality analysis and food processing technology. Using another, larger, MEMS-based scanning grating spectrometer, we perform a series of test measurements of the absorption of different types of oil. Thereby, we demonstrate the suitability of this larger MEMS-based SGS for food quality analysis and establish a set of reference measurements. The optical parameters of the sugar cube-sized SGS are then evaluated against the requirements established in the above reference measurements. The spectral resolution of this device is still not sufficient for application in the near infrared, owing to the inaccuracy of one particular production step. Once these changes are in place, we are confident to achieve resolutions below 20 nm. In conclusion, we propose the miniaturised SGS as a mobile spectrometer for insitu analysis integrated with a data processing system.