Fig. 1. Schupmann achromatic model

Fig. 2. Partial optical path diagram of 10 m diffractive optical system with a traditional diffractive lens

Fig. 3. Fresnel lens and harmonic diffractive lens. (a) Fresnel lens; (b) harmonic diffractive lens

Fig. 4. Optical path diagram of 10 m diffractive optical system

Fig. 5. MTF of each wave band of the system. (a) 400‒420 nm; (b) 420‒550 nm; (c) 550‒750 nm; (d) 750‒900 nm

Fig. 6. Spot diagram of the system. (a) 400‒420 nm; (b) 420‒550 nm; (c) 550‒750 nm; (d) 750‒900 nm

Fig. 7. Energy diagram of different bands. (a) 400‒420 nm; (b) 420‒550 nm; (c) 550‒750 nm; (d) 750‒900 nm

Fig. 8. Optical path diagram of 80 mm diameter system

Fig. 9. MTF of 80 mm diameter system. (a) 400‒420nm; (b) 420‒550 nm; (c) 550‒750 nm; (d) 750‒900 nm

Fig. 10. Spot diagram of the 80 mm system. (a) 400‒420 nm; (b) 420‒550 nm; (c) 550‒750 nm; (d) 750‒900 nm

Fig. 11. Energy diagram of different bands. (a) 400‒420 nm; (b) 420‒550 nm; (c) 550‒750 nm; (d) 750‒900 nm

Fig. 12. Harmonic diffractive lens. (a) Harmonic diffractive lens; (b) 16-level structure of the harmonic diffractive lens

Fig. 13. Optical path diagram of the experiment. (a) Physical map; (b) enlarged view

Fig. 14. Measured MTF of the 80 mm system. (a) 400‒420 nm; (b) 420‒550 nm; (c) 550‒750 nm; (d) 750‒900 nm

Fig. 15. Imaging of the discrimination rate target