J. Hohlbein and C.G. Hübner, Applied Physics Letters, 86, 121104, 2005, [link]
One of the unique features of single molecule absorption and emission is their anisotropy due to the well-deﬁned transition dipole(s) for both processes allowing the determination of the molecule’s orientation. While polarization-resolved techniques are usually capable of detecting only a projection of the transition dipole, several methods have been proposed in order to determine the full three-dimensional orientation. Here, we report on a detection scheme that allows for a shot-noise limited determination of the emission dipole orientation utilizing an annular mirror, a polarizing beam splitter in conjunction with three detectors in a scanning confocal optical microscope.