(a) FLIm lateral PSF FWHM, (b) OCT lateral PSF FWHM, and (c) FLIm and OCT on-axis collection efficiency, all plotted as a function of distance from the GRIN lens. (d) OCT B-scan of a roll of Scotch tape. (e) Multispectral fluorescence lifetime image of six glass capillaries containing (left–right) elastin, bovine Achilles tendon type I collagen, FAD, unbound NADH, coumarin 120, and rhodamine B. The lifetime values are overlaid onto the surface of the capillaries that was segmented from the co-registered OCT dataset.