Effects of Annular Pupils on Confocal Fluorescent Imaging

Abstract

For a confocal fluorescent microscope with annular lenses, the effects of varying the radii of central obstruction of the annular lenses on three, two and one-dimensional imaging have been investigated in terms of the optical transfer function. In particular, we consider the effects of the central obstruction on the signal strength for a system with either a point or finite-sized detector. The signal level as a function of the detector and the central obstruction sizes is presented for volume, planar and point objects, respectively.