Fig. 1. The schematic diagram of one-photon and two-photon 3D printing

Fig. 2. The schematic diagram of fabrication of reciprocal plasmonic metasurface and its reflection spectrum^[29]

Fig. 3. The schematic diagram of stereostructured U-shaped resonator metallic film^[30]

Fig. 4. The microring zone metasurface probe^[31]

Fig. 5. The Plasmonic nanoantenna for SEIRA fabricated by the first method^[32]

Fig. 6. The second method of fabricating plasmonic nanoantenna for SEIRA^[33]

Fig. 7. The procedure diagram of plasmonic metasurface fabrication by two-photon 3D printing

Fig. 8. Metallic slit microlens^[38]

Fig. 9. The multilayer planar lens^[39]

Fig. 10. The SLAC flat lens^[40]

Fig. 11. HAML^[41]

Fig. 12. CMCD^[42]

Fig. 13. The fabrication and focusing effect of SOL^[43]

Fig. 14. The two-color anisotropic nanoemitter^[44]

Fig. 15. The nanoscale full color and grayscale 3D painting^[45]

Fig. 16. The reconfigurable hologram metasurface^[46]

Fig. 17. The principle of designing complex-amplitude OAM holography in momentum space^[47]

Fig. 18. The schematic diagram of decryption function implemented by the all-optical MLD ^[48]

Fig. 19. The SZP structure on the fiber facet fabricated by two-photon 3D printing^[49]

Fig. 20. The KSZP structure on the composite fiber facet fabricated by two-photon 3D printing^[50]

Fig. 21. Ultrahigh NA meta-fiber^[51]

Fig. 22. The achromatic meta-fiber for achromatic focusing and imaging^[52]

Fig. 23. A 3D radar-like SERS sensor fabricated on an optical fiber^[53]

Fig. 24. The schematic of the fabrication process of SERS arrays sensor probes on the fiber facets by two-photon 3D printing^[54]

Fig. 25. Integrated optical elements on fiber facets fabricated by two-photon 3D printing^[18]