Fig. 1. Basic optical path of the echelle grating spectrometer

Fig. 2. Relationship between grating angular dispersion rate and m, ν and θ_m

Fig. 3. Angular dispersion rate of the grating when θ_m=63°

Fig. 4. Relationship between wavelength and order within a specific diffraction angle range. (a) Short wave band; (b) long wave band

Fig. 5. Optical path of the reflecting prism

Fig. 6. Relationship between deflection angle and prism vertex angle and light incident angle

Fig. 7. Optical path structure of the spectrometer

Fig. 8. Spot diagrams of system. (a) 402.31 nm and 402.313 nm; (b) 541.82 nm and 541.824 nm; (c) 870.475 nm and 870.48 nm

Fig. 9. Aberration of system. (a) 402.31 nm and 402.313 nm; (b) 541.82 nm and 541.824 nm; (c) 870.475 nm and 870.48 nm

Fig. 10. Two-dimensional dispersion spectrum