Fig. 1. Light trace map at the cold stop under different fields of view

Fig. 2. Optical path structure diagrams of cooled infrared optical system

Fig. 3. MTF of normal infrared optical system at different defocus values

Fig. 4. Relationship curve between MTF and $\alpha$ at 33 lp/mm in wavefront coding system

Fig. 5. Cosine similarity curves of MTF at different defocus values

Fig. 6. MTF of wavefront coding system at different defocusing amounts

Fig. 7. PSF images of normal infrared system at different defocusing amounts

Fig. 8. PSF images of wavefront coding system at different defocusing amounts

Fig. 9. Simulation images of normal infrared optical system

Fig. 10. Blur images of wavefront coding system

Fig. 11. Restored images of wavefront coding system