Fluorescence lifetime imaging for the two-photon microscope: time-domain and frequency-domain methods
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Updated: Sep 21, 2026

Fluorescence Lifetime Imaging of Molecular Rotors in Living Cells
Published on: February 9, 2012
Enrico Gratton1, Sophie Breusegem, Jason Sutin
1University of Illinois at Urbana-Champaign, Laboratory for Fluorescence Dynamics, 1110 West Green Street Urbana, Illinois 61801, USA. Enrico@scs.uiuc.edu
Abstract:
Fluorescence lifetime images are obtained with the laser scanning microscope using two methods: the time-correlated single-photon counting method and the frequency-domain method. In the same microscope system, we implement both methods. We perform a comparison of the performance of the two approaches in terms of signal-to-noise ratio (SNR) and the speed of data acquisition. While in our practical implementation the time-correlated single-photon counting technique provides a better SNR for low-intensity images, the frequency-domain method is faster and provides less distortion for bright samples.
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