Figure 3.

CARS and SRS images of the T. parvulaleaf surface. The surface of a leaf from T. parvula was simultaneously imaged using CARS microscopy (A) and SRS microscopy (B). Both images were acquired at a 2,845 cm^–1 CH₂ symmetric stretch. The CARS image (A) is dominated by autofluorescence, and only the largest wax crystals are visible against the background. Conversely, the SRS image (B) is almost background free, enabling the cell walls and wax crystals to be clearly visualized. C shows the spectral scan of the SRS (red crosses) from the wax crystals in situ overlaid onto the spontaneous Raman spectra of purified T. parvula wax (blue line), purified cellulose (green line), and purified pectin (purple line).