A wide field catadioptric imaging spectrometer with an immersive
diffraction grating that compensates optical distortions. The
catadioptric design has zero Petzval field curvature. The imaging
spectrometer comprises an entrance slit for transmitting light, a system
with a catadioptric lens and a dioptric lens for receiving the light and
directing the light, an immersion grating, and a detector array. The
entrance slit, the system for receiving the light, the immersion grating,
and the detector array are positioned wherein the entrance slit transmits
light to the system for receiving the light and the system for receiving
the light directs the light to the immersion grating and the immersion
grating receives the light and directs the light through the system for
receiving the light to the detector array.