Image Formation in Wide-Field Microscopes Based on Leakage of Surface Plasmon-Coupled Fluorescence

A proof-of-concept imaging technique that combines the advantages of wide-field surface plasmon, leakage radiation, and total internal reflection fluorescence microscopy methods is presented. High-contrast non-scanning images with subwavelength resolution of patterned and homogeneous samples coated with a fluorescent material were demonstrated. We show that the image formed in the back focal plane of the objective lens can be reconstructed from the image of the sample's surface using an algorithm similar to that used in computerized tomographic imaging. Our experimental results suggest that there is a 1-D Fourier transform relationship between any line amplitude profile at a given angle passing through the center of the sample's surface image and a line amplitude profile passing through the center of the back-focal-plane image at the same angle.