Brewster Angle Microscopy
This microscopy technique allows the direct observation of ultrathin organic films on transparent dielectric substrates. It is based on the effect that from the clean surface no reflection occurs when p-polarized incoming light under the Brewster angle.
The "black background" of the Brewster angle setup allows using the detector (CCD-camera) with the maximum of intensity. A very thin organic layer (e.g. a monolayer with typ. 2 nm) with different refractive index will cause reflection. Typically, the resulting reflection is only about a millionth of the incident intensity.
The reflected light can be used to form a high contrast image of the lateral morphology of the layer, with applications in the life sciences and materials research.
More about Imaging Ellipsometry.