Design study of a compact ultra-wide-angle high-spatial-resolution high-spectral-resolution snapshot imaging spectrometer

Abstract

An ultra-wide-angle high-spatial-resolution high-spectral-resolution snapshot imaging spectrometer (UWA-2HSR-SIS) is presented, which comprises a microlens array (MLA), multiple fiber bundles, a micro-cylindrical-lens array (MCLA), a cylindrical lens, a static grating interferometer (SGI), and an area-array detector. The MLA is arranged in a circular arc of 120° or more. The MCLA is arranged in a straight line. The SGI includes a fixed reflection grating in Littrow configuration, a beam splitter, and a fixed plane mirror. Each fiber bundle containing multiple optical fibers is coupled to a separate microlens of the MLA, subdividing the field angle of each microlens into multiple smaller field angles. The light passing through each subdivided smaller field angle of each microlens of the MLA is received by a separate part of the detector. The UWA-2HSR-SIS is a new concept that not only obtains both high spatial resolution and high spectral resolution based on a single sensor for the first time, but also has an ultra-wide field angle in the horizontal plane, can obtain spectral information covering the full spectral range of interest in real time, and is very stable against various disturbances. The UWA-2HSR-SIS has great potential for remote sensing electro-optical reconnaissance sensors in the visible and near-infrared region.