Effect of a confocal pinhole in two-photon microscopy
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Published on: August 11, 2020
R Gauderon1, P B Lukins, C J Sheppard
1Physical Optics Department, School of Physics A28, University of Sydney, NSW 2006, Australia.
Abstract:
We investigated the effect of a finite-sized confocal pinhole on the performance of nonlinear optical microscopes based on two-photon excited fluorescence and second-harmonic generation. These techniques were implemented using a modified inverted commercial confocal microscope coupled to a femtosecond Ti:sapphire laser. Both the transverse and axial resolutions are improved when the confocal pinhole is used, albeit at the expense of the signal level. Therefore, the routine use of a confocal pinhole of optimized size is recommended for two-photon microscopy wherever the fluorescence or harmonic signals are large.
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