Miniaturizing Fourier Transform Spectrometer With an Electrothermal Micromirror

An amplitude-division Fourier transform spectroscopy system has been constructed. The system design hinges on an electrothermally actuated micromirror with large piston motion. The micromirror is composed of electrothermal mesh actuators and can generate up to 95 μm usable linear optical path difference of the system at only 0.8 V_dc. A custom electrical system is developed to control the micromirror and data processing is implemented to extract the spectrum from interferograms. The system can achieve a spectral resolution of 5 nm at 532 nm.