Fig. 2.

a) cartoon showing the fast and slow axes of a raster scan along with frame labels referenced in the trigger diagrams of b). The arrows represent the movement of the collinear OCT and FLIM beams steered by the galvo mirrors during imaging. b) Trigger diagrams for signals used to sample OCT and FLIM. The temporal sampling rates are fixed according to sweep rate of the OCT swept source (50 kHz) and the pulse repetition rate of the FLIM excitation lasers (10 kHz). For brevity only 10 OCT lines and 2 FLIM pixels are acquired per frame in this illustration. i) sweep trigger from swept source acts as the master clock. ii) internal trigger logic on FPGA/digitizer that omits the triggers during the galvo flyback. iii) 10 kHz digitial signal output by the analog output card and sent to a delay generator. iv) undelayed trigger signal from delay generator used to trigger 355 nm laser. v) 50 μs delayed trigger signal used to trigger 532 nm laser. vi) photodiode signal used to trigger FLIM digitizer.