Deconvolution in Acousto-Optical Tunable Filter Spectrometry

Abstract

Spectrometers and spectral imaging systems based on the acousto-optical tunable filter (AOTF) are becoming commonly used in many different fields in which high spectral resolution is crucial, e.g., laser-induced breakdown spectroscopy, Raman spectroscopy, and absorption spectroscopy of gases. As AOTFs have many advantages over other spectroscopic instruments but lack spectral resolution, a procedure for resolution enhancement, composed of point spread function characterization and spectrum preprocessing and deconvolution, is proposed. Wiener, Fourier-wavelet regularized (ForWaRD), Richardson–Lucy, and Wavelet–Lucy deconvolution methods were tested and their performances assessed with two deconvolution quality measures: resolution enhancement and noise amplification. It was shown that the proposed spectral resolution enhancement is feasible and gives good results for line spectra and highly dynamic spectra.