Fig. 1. Multi-mode nonlinear optical imaging system. (a) Schematic diagram of the structure design of the multi-mode nonlinear optical imaging system; (b) picture of Olympus FVMPE-RS microscope

Fig. 2. Test for two-photon imaging function. (a) Two-photon imaging of anthracene crystals; (b) two-photon fluorescence spectra of anthracene crystals

Fig. 3. Test for SRS imaging function. (a) Bright field imaging of PMMA; (b) SRS imaging effect; (c) Raman spectra of PMMA

Fig. 4. Optimization of SRS resonance conditions. (a) SRS images of PMMA varying with the delay time of two wavelength lasers; (b) SRS images of PMMA associated with the pump laser wavelength

Fig. 5. Schematic diagram of plasmon enhanced FWM. (a) Diagram showing the coupling of surface plasmon resonance for energy levels for FWM; (b) local electromagnetic field simulations of Ag and Au nanoparticles in FWM; (c) FWM image of metal nanoparticles recorded by the self-built multi-photon microscope

Fig. 6. TEM image of gold nanoparticles

Fig. 7. Thin-section images of mouse liver and kidney tissue