ELECTROMAGNETIC DESCRIPTION OF IMAGE-FORMATION IN CONFOCAL FLUORESCENCE MICROSCOPY

Using an electromagnetic approach, we calculate the properties of a co nfocal fluorescence microscope. It is expected that the results will b e more reliable than those obtained by conventional scalar theory, the results of which differ significantly from ours. We calculate the poi nt spread function and the optical transfer function and study the inf luence of detector size and fluorescence wavelength on the optical sec tioning capability. Our calculations are based on electromagnetic diff raction theory in the Debye approximation. The recently noted asymmetr y between the illumination and the detection sensitivity distribution is also taken into account.