Time-gated single photon counting enables separation of CARS microscopy data from multiphoton-excited tissue autofluorescence.
We demonstrate time-gated confocal imaging as a means to separate coherent anti-Stokes Raman scattering (CARS) microscopy data from multi-photon excited endogenous fluorescence in tissue. CARS is a quasi-instantaneous process and its signal decay time is only limited by the system's instrument response function (IRF). Signals due to two-photon-excited (TPE) tissue autofluorescence with excited state lifetimes on the nanosecond scale can be identified and separated from the CARS signal by employing time-gating techniques. We demonstrate this improved contrast on the example of CARS microscopy of intact roots of plant seedlings as well as on rat arterial tissue.
Ly
Sonny
S
McNerney
Gregory
G
Fore
Samantha
S
Chan
James
J
Huser
Thomas
T