In a stimulated emission depletion (STED) microscope the region from which a fluorophore can spontaneously emit shrinks with the continued STED beam action after the excitation event. This fact has been recently used to implement a versatile, simple and cheap STED microscope that uses a pulsed excitation beam, a STED beam running in continuous-wave (CW) and a time-gated detection: By collecting only the delayed (with respect to the excitation events) fluorescence, the STED beam intensity needed for obtaining a certain spatial resolution strongly reduces, which is fundamental to increase live cell imaging compatibility. This new STED microscopy implementation, namely gated CW-STED, is in essence limited (only) by the reduction of the signal associated with the time-gated detection. Here we show the recent advances in gated CW-STED microscopy and related methods. We show that the time-gated detection can be substituted by more efficient computational methods when the arrival-times of all fluorescence photons are provided.

Date Published: 9 March 2015
PDF: 7 pages
Proc. SPIE 9331, Single Molecule Spectroscopy and Superresolution Imaging VIII, 93310X (9 March 2015); doi: 10.1117/12.2081553

Published in SPIE Proceedings Vol. 9331:
Single Molecule Spectroscopy and Superresolution Imaging VIII
Jörg Enderlein; Ingo Gregor; Zygmunt Karol Gryczynski; Rainer Erdmann; Felix Koberling, Editor(s)