Tunable Acousto-Optic Filter for the 450–900 and 900–1700 nm Spectral Range

The problem of creating an acousto-optic (AO) tunable filter, which allows us to obtain high-quality spectral images both in the visible and near-infrared ranges, is studied. Based on the analysis of the wide-aperture noncollinear geometry of AO diffraction in paratellurite, the AO cell configuration is determined that is optimal in terms of minimizing chromatic shift and is suitable for both ranges. Two identical cells are manufactured and matched for the ranges 450–900 and 900–1700 nm. Experimental verification of the results of optical modeling showed that, over the entire range of 450 to 1700 nm, the calculated AO filter provides high-quality spectral images.