We tested the performance of a fast single-photon avalanche photodiode (SPAD) in measurement of early transmitted photons through diffusive media. In combination with a femtosecond titanium:sapphire laser, the overall instrument temporal response time was 59 ps. Using two experimental models, we showed that the SPAD allowed measurement of photon-density sensitivity functions that were approximately 65% narrower than the ungated continuous wave case at very early times. This exceeds the performance that we have previously achieved with photomultiplier-tube-based systems and approaches the theoretical maximum predicted by time-resolved Monte Carlo simulations.
© 2013 Optical Society of America
Original Manuscript: March 20, 2013
Revised Manuscript: May 13, 2013
Manuscript Accepted: May 13, 2013
Published: June 10, 2013
Vol. 8, Iss. 7 Virtual Journal for Biomedical Optics
Ying Mu, Niksa Valim, and Mark Niedre, "Evaluation of a fast single-photon avalanche photodiode for measurement of early transmitted photons through diffusive media," Opt. Lett. 38, 2098-2100 (2013)