Fig. 1. Lab-on-fiber paradigm and multifunctional integration on fiber tips

Fig. 2. Microscopic images of end cone of ring core fiber and illumination images of surface plasma wave under different input optical powers^［12］

Fig. 3. Spherical lenses with different curvatures prepared at fiber tip by arc discharge method^［20］

Fig. 4. Preparation of surface enhanced Raman spectroscopy sensor based on chemical etching process of optical fiber end face^［25］

Fig. 5. Periodic nano arrays prepared on gold film at end of optical fiber by focused ion beam process^［36］

Fig. 6. High activity SERS substrate prepared by femtosecond laser on end face of fiber^［37］

Fig. 7. Morphology of gold nanodot arrays prepared at fiber tip by electron beam lithography^［49］

Fig. 8. Schematic diagram of self-assembled gold nanopore structure prepared at tip of fiber

Fig. 9. Fiber tip lens prepared by two-photon polymerization process and its performance^［63］

Fig. 10. Schematic diagram of transferring gold nanostructures to fiber end face by thin film release method^［72］

Fig. 11. Typical process flow of transferring metallic metasurface by adhesive method based on heat curing glue^［96］