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Updated: May 8, 2026
Measuring Diffusion Coefficients via Two-photon Fluorescence Recovery After Photobleaching
Published on: February 26, 2010
Evaluation of a fast single-photon avalanche photodiode for measurement of early transmitted photons through
Ying Mu1, Niksa Valim, Mark Niedre
1Department of Electrical and Computer Engineering, Northeastern University, Boston, Massachusetts 02115, USA.
Abstract:
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.
