Mid-infrared tunable MEMS Fabry–Pérot interferometer operated at the first interference order

Results of tunable MEMS FPI operated in first interference order for the range of mid-infrared were presented. The HR coating is designed as two stacks of SiO / Ge QWOT Bragg reflectors. The AR was designed carefully to eliminate the stress mismatch induced by AR and HR coatings. The center wavelength tune from 4948 nm to 3612 nm actuated by 36.5 V control voltage. The FWHM of all spectra vary between 42 nm to 82 nm. The peak transmittances are large than 60% for all measured spectra.