Broadband static Fourier transform mid-infrared spectrometer.

For applications where only moderate spectral resolution is required, static Fourier transform infrared spectrometers (sFTS) offer a comparatively cost-effective alternative to classical scanning instruments. In this paper, we present an sFTS based on a single-mirror interferometer using only standard optical components and an uncooled microbolometer array. Because the instrument features concave mirrors rather than lenses, dispersion effects can be minimized. This enables broadband operation in the mid-infrared range from 2800  cm to 600  cm at a spectral resolution of 12  cm. In addition, the design guarantees comparatively high light throughput and can potentially be designed for increased temperature stability. Alongside a simulation of the temperature- and wavenumber-dependent behavior of the system, we provide a proof of principle of the proposed design by means of experimental results.