Rotational echelle grating spectrometer with adjustable AOTF for atmospheric observation.

High-spectral resolution improves the retrieval accuracy of planetary atmospheric constituents but increases spectral dispersion length, leading to larger system volume and detector size in broadband observations, which limits spaceborne applications. To address this issue, a broadband high-spectral resolution imaging spectrometer based on a spectral-resolution-adjustable AOTF and a rotational echelle grating is proposed. By adjusting the grating operating state, efficient spectral matching between the AOTF output spectrum and the characteristic absorption lines of different target species is achieved. Simulation results demonstrate that the proposed method improves the diffraction efficiency at characteristic wavelengths, enhances spectral matching performance, and increases the effective observation capability of target absorption lines over a broad spectral range. This approach provides an effective solution for broadband, high-spectral resolution, and miniaturized planetary atmospheric remote sensing instruments.