Fig. 1. Spectral distortion of imaging spectrometer. (a) Without spectral distortion; (b) with spectral distortion

Fig. 2. Diagram of simplified model for plane grating spectrometer system

Fig. 3. Curves of spectral distortion varying with half FOV for transmissive plane grating spectrometer system. (a) Smile; (b) keystone

Fig. 4. Different vertex angle directions of prism. (a) Vertex angle faces chief ray of edge FOV; (b) vertex angle faces chief ray of central FOV

Fig. 5. Curves of spectral distortion and half FOV for spectrometer system with prism grating and prism. (a) Smile; (b) keystone

Fig. 6. Diagram of spectrum after correction by prism

Fig. 7. Diagram of negative distortion generated by focusing system

Fig. 8. Diagrams of four spectrometer system layouts. (a) PG structure; (b) P+PG structure; (c) PG+P structure; (d) PG+P+P structure

Fig. 9. Layout of imaging spectrometer

Fig. 10. Spot diagrams of imaging spectrometer. (a) 747 nm; (b) 762 nm; (c) 777 nm

Fig. 11. MTF curves of imaging spectrometer. (a) 747 nm; (b) 762 nm; (c) 777 nm

Fig. 12. Spectral distortion curves of imaging spectrometer. (a) Smile; (b) keystone