Fig. 1. Relation between focal depth and defocus of apochromatism system

Fig. 2. Relationship between focal depth and defocus of two-band system

Fig. 3. An 0.48−1.7 μm ultra wide band objective and its MTF curves

Fig. 4. An 0.65−1.7 μm wide band objective lens and its MTF curves

Fig. 5. A tri-band co-path optical system and its MTF curves

Fig. 6. A small multi-band optical system and its LWIR MTF curves

Fig. 7. IRIS-T and seeker’s optical system

Fig. 8. A compact dual-band optical system and its MTF performances

Fig. 9. A MWIR and LWIR dual-band common optical path zoom system and their MTF performances

Fig. 10. A TV and MWIR dual-band common aperture zoom optical system and their MTF performances

Fig. 11. TV and MWIR multi-band common aperture optical system used by Sniper XR pod and their MTF curves

Fig. 12. A NIR/MWIR dual-band mirror-lens common aperture optical system

Fig. 13. A NIR/MWIR/LWIR multi-band mirror-lens common aperture optical system

Fig. 14. Three-mode seeker of Raytheon SDB Ⅱ bomb

Fig. 15. A dual-mode seeker optical layout and its LWIR MTF performance curves

Fig. 16. Reflective lens structure used by EKV

Fig. 17. A coaxial triple mirror fore-telescope system

Fig. 18. TMA fore-telescope system used by MTS-B pod

Fig. 19. Off-axis TMA fore-telescope system used by ATFLIR pod