Calibration method for the center of mass method to enlarge the solvable range of fluorescence lifetime.

This paper presents a calibration method for the center of mass method based on rough rapid lifetime determination (RLD) to enlarge the solvable range of fluorescence lifetime. The proposed method defines the ratio of two photon count numbers as a threshold parameter to characterize the length of the sample lifetime. When detecting long lifetimes beyond the threshold, a raw lifetime is estimated first through RLD. Then the raw lifetime is compensated to get a precise one. Simulation results show the solvable range is extended from T/τ>4 to T/τ>1.5 with less than 1% error. The extended range with 40 dB SNR guaranteed enables higher-frequency laser pulses to solve long lifetimes or incomplete decays and has promising biomedical applications, such as quantum dots.