High-resolution wide-field surface plasmon microscopy

This paper describes the application of a Köhler illuminated high-resolution wide-field microscope using surface plasmons to provide the image contrast. The response of the microscope to a grating structure in both the Fourier and the image planes is presented to demonstrate image formation by surface waves. The effect of spatial filtering in the back focal (Fourier) plane to enhance image contrast is described. We also discuss how the surface wave contrast mechanism affects the imaging performance of the microscope and discuss factors that can be expected to lead to even greater improvements in lateral resolution and sensitivity.