Polarization contrast in fluorescence scanning near-field optical reflection microscopy

Polarization contrast is presented in fluorescence images of a Langmuir–Blodgett monolayer obtained with a scanning near-field optical microscope operated in reflection. A tapered optical fiber is used both to excite and to collect the fluorescence. The lateral resolution in the reflection fluorescence image is estimated at 200 nm. Shear-force detection controls the tip-to-surface distance and simultaneously gives a topographic map. Direct correlation between topography and the fluorescent domain is thus obtained. We show that the fluorescence is polarized along the molecular orientation in the Langmuir–Blodgett monolayer. Thus we demonstrate the study of the polarization direction in the reflection mode.