An Ultra-miniaturized Mid-infrared Spectrometer with no Moving Parts for Photochemical Analysis

We demonstrate for the first time an ultra-miniaturized spectrometer with no moving parts based on a 2-step Fabry-Perot filter array for online liquid phase photochemical reaction spectrum analysis in the mid-infrared (MIR) wavelength range (3-5 μm). The system can realize stable and fast detection with both spectral and spatial resolution in an extremely robust configuration. We discuss design and fabrication of this spectrometer array, which has spectral transmission characteristics with a FWHM of 110 nm around 4.7 μm. The capabilities of monitoring the synthesis of 2,1-benzisoxazolonon from 2-azidobenzoic acid are demonstrated.