FLIM has become an important tool to assess the biochemical environment of fluorescent molecules and probes.

Upon excitation, fluorescent molecules emit light and the fluorescent lifetime quantifies the decay rate of that emitted light. The fluorescence lifetime is a telltale signature of the molecules and their immediate environment.

FLIM is the technique which maps the spatial distribution of lifetimes in living cells and in inorganic material. Fluorescence lifetime is independent of concentration, bleaching and intensity variations, making it an inherently quantitative technique, and a key advantage over the light intensity.