Diffraction in high numerical aperture systems: Polarization effects

Abstract

In high numerical aperture systems polarization effects should be taken into account; hence it is necessary to use a vectorial diffraction theory to describe them. We develop a computational model to study image formation in a high numerical aperture microscope objective by simulating images of self-luminous, non-polarized point objects. We compare the predictions made by scalar and vectorial theories of diffraction. In the last case we also consider an analyzer placed behind the objective to study the polarization effects. We find that vectorial theory predicts a larger diffraction pattern and, when an analyzer is used, an enlargement along the transmission axis of the analyzer. We also study the resolution of the system, finding that the true resolution predicted for vectorial theory is approximately 10% lower than that usually expected for scalar theory.