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.