Wide-band large-aperture Ag surface-micro-machined MEMS Fabry-Perot interferometers (AgMFPIs) for miniaturized hyperspectral imaging

Small, tunable MEMS Fabry-Perot interferometer (FPIs) have recently been demonstrated to enable hyperspectral imaging in mobile devices, so far using Bragg reflector mirror technologies, which however limit the device tuning range. This paper presents the realization of a novel MEMS FPI structure based on Ag thin film mirrors (AgMFPI), which allows tuning the entire visible - very near infrared (VNIR) wavelength range (for example 450 - 900 nm) with one single component. The characterized transmission of the components is 12 - 45% with full-width-half-maximum values (FWHM) between 11 - 18 nm using 2 mm optical aperture, while using 3 mm optical aperture results in FWHM values of 12 - 20 nm. A very compact hyperspectral imager can thus be built to cover this spectra by combining this AgMFPI and a typical RGB type of image sensor.