Two-dimensional fluorescence lifetime imaging for in-vitro and in-vivo application

We report the development of a fluorescence lifetime imaging (FLIM) system based on a time-gated image intensifier and solid-state laser amplifier with a system response of < 100 ps. We have sued this system to image lifetimes as short as 100 ps and to image changes in the environment of a fluorescent phantom, causing lifetime differences less than 10 ps. The versatility of this FLIM system has been demonstrated by measuring both the temporal and spectral profiles of multiple fluorescent samples in a single acquisition. Fluorescence lifetime imaging of tissue constituents has also been carried out and first results suggest that this technique can provide a means of distinguishing between different tissue constituents.