The acousto-optic tunable filter is a solid state, electronically tunable device suitable for rapid-scanning spectrometer applications. The spectral resolution of the AOTF spectrometer is limited by the size of the acousto-optic crystal. This paper discusses techniques to increase the resolution of an AUTF spectrometer witnout losing its other inherent advantages, particularly its large optical tnroughput. Utilizing an AUTF in optical cascade with a scanning Fabry-Perot interferometer, resolvable bandwidth of 0.8/A was obtained at 3.39 microns.
I. C. Chang,
"Acousto-Optic Tunable Filters For High Resolution Spectral Analysis", Proc. SPIE 0268, Imaging Spectroscopy I, (21 July 1981); doi: 10.1117/12.959939; https://doi.org/10.1117/12.959939