Journal of Fluorescence

, 19:381 | Cite as

Exploring the Nature of Photo-Damage in Two-photon Excitation by Fluorescence Intensity Modulation

Rapid Communication


We investigate the relative photo-damage effects during one- and two-photon excitations and demonstrate that there exist fundamental differences in the damage induced by a high repetition rate laser as compared to that of a CW laser. This difference is evident from the degree of enhanced fluorescence intensity achieved by blanking the excitation with an optical chopper. Such an enhancement in fluorescence intensity provides better signal-to-noise ratio that could have immediate applications in multiphoton imaging of live specimens.


Two-photon cross-section Photo-damage Fluorescence enhancement Multiphoton imaging 



AKD thanks CSIR, India for graduate fellowship. The authors thank MCIT and DST, India and Wellcome Trust Foundation, UK for funding. We acknowledge Debjit Roy for his assistance.


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Department of ChemistryIndian Institute of Technology KanpurKanpurIndia

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