Fig. 3. (a) Photograph of FOPs without (left) and with (right) FND coatings prepared by electrospray deposition. Dimensions of the FOPs were 14 × 14 mm2. (b) Fluorescence intensity line profile across the center of an FND film on an FOP. (c and d) Wide-field fluorescence image (c) and fluorescence intensity line profile (d) of an FND film on an FOP. The white line in (c) denotes the data points in (d), which were fitted with two Gaussian functions (black).
