Modified Dyson imaging spectrometer with an aspheric grating surface

A broadband, aberration-corrected Dyson arrangement with an aspheric grating surface is proposed. An aspheric grating surface is used to correct spherical aberration resulted from the air gap between the focal plane and the rear surface of Dyson lens. The principle and the method of aberration correction are described in detail. We compare the performance of this modified Dyson arrangement with that of the Dyson arrangement using a spherical grating surface by using a practical Dyson imaging spectrometer example.