FLIM involves exciting a sample with a short pulse of light and then measuring the time it takes for the emitted fluorescence to decay. This decay time, or lifetime, is typically in the range of picoseconds to nanoseconds. The technique can be implemented using various types of detectors, such as time-correlated single photon counting (TCSPC) or frequency-domain methods. The lifetime data is then used to create a lifetime map of the sample, which can reveal information about the molecular environment, including polarity, pH, and protein interactions.
