A micro-mechanical fresnel lens for spectral filtering

Abstract

In this paper, there has been a recent interest for MEMS-based adjustable or re-configurable diffraction filters. Reconfigurable diffraction filters are well adapted to NIR spectroscopy, with applications such as identification of polymers and detection of carbon monoxide in air. A cost-effective implementation of a NIR spectrometer was proposed by Lovhaugen. The system uses a focusing static Diffractive Optical Element (DOE). The set-up minimizes the number of elements in the system, as no lens is needed