Influence of interface-dipole interactions on the efficiency of fluorescence light collection near surfaces.

Recently Török and colleagues published in a series of papers a general wave-optical approach to calculating the light-collection efficiency function (CEF) for confocal imaging of dipole emitters [J. Mod. Opt. 45, 1681 (1998); J. Microec. 194, 127 (1999); Opt. Lett. 25, 1463 (2000)]. In their theory they did not address the possibility that the lifetimes of fluorescing molecules can change significantly near interfaces, which has a direct effect on the CEF. The research of Török and colleagues is extended here to include this effect, which may become important for imaging near surfaces.