All these formulas for confocal microscope resolution assume a 
homogeneously illuminated back-aperture, which is not always the case in 
commercially available microscopes due to the Gaussian intensity profile 
of the excitation laser beam. Therefore, the lateral resolution of a 
confocal microscope can even be worse than of a widefield fluorescence 
microscope with arc-lamp illumination.

-- 
arwed weigel
abteilung fuer neurophysiology und zellulaere biophysik
universitaet goettingen
humboldtallee 23
37073 goettingen

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