DYSON-TYPE IMAGING SPECTROMETER HAVING IMPROVED IMAGE QUALITY AND LOW DISTORTION

摘要

A Dyson imaging spectrometer includes an entry port extending in a direction X, an exit port, a diffraction grating including a set of lines on a concave support, an optical system including a lens, the lens including a plane first face and a convex second face, the convex face of the lens and the concave face of the diffraction grating being concentric, the optical system being adapted to receive an incident light beam coming from the entry port and to direct it toward the diffraction grating, to receive a beam diffracted by the diffraction grating, and to form a spectral image of the diffracted beam in a plane of the exit port, the spectral image being adapted to be spatially resolved in an extension direction X' of the image of the entry port. The diffraction grating includes a set of non-parallel and non-equidistant lines and/or the support of diffraction grating is aspherical in order to form an image of the entry port in the exit plane of improved image quality and of very low distortion.