Fig. 6: CASPI for FLIM.
From: CASPI: collaborative photon processing for active single-photon imaging
a CASPI enables reliable lifetime estimates with as few as 10 photons per pixel and achieves 5× better performance in root-mean-square error (RMSE) compared to spatial binning of the photon transient cubes followed by BM3D applied to the lifetime estimates. The sample imaged here contains fixed BPAE endothelial cells with fluorescent labels. DAPI stained nuclei and mitotracker stained mitochondrial structures are separable using CASPI even with 50× fewer photons than the ground-truth. b, c CASPI recovers the underlying transients from the autofluorescence emission (last column) from the low photon count datasets of autofluorescence of biological samples. When combined with existing fitting methods ((b) state-of-the-art maximum likelihood estimation (MLE), or (c) naive linear-fit on log-transformed histograms), CASPI enables to recover fine structures and details even for moving living cells (see also, Supplementary Video).
