Long working distance fluorescence lifetime imaging with stimulated emission and electronic time delay.

In this work, long working distance fluorescence lifetime imaging is realized with stimulated emission in combination with electronic time delay control. Spatial coherence, as a result of stimulated emission, supports unattenuated fluorescence detection at extended distance, using low NA optics. An electronic time delayed trigger provides an advantageous way in adjusting the pulse separation and probing the fluorescence lifetime in the nanosecond ranges. The fluorescence lifetime of selected fluorophores is accurately determined through the pump-probe configuration. The characteristics and applications in fluorescence lifetime measurement of stimulated emission are investigated and summarized succinctly here.