Research Article Vol. 12, No. 6 / 1 June 2021 / Biomedical Optics Express 3450 Dynamic fluorescence lifetime sensing with CMOS single-photon avalanche diode arrays and deep learning processors DONG XIAO,1,2 ZHENYA ZANG,1,2 NATAKORN SAPERMSAP,3 QUAN WANG,1,2 WUJUN XIE,1,2 YU CHEN,3 AND DAVID DAY UEI LI1,2,* 1Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, Scotland, UK 2Department of Biomedical Engineering, University of Strathclyde, Glasgow G1 1XQ, Scotland, UK 3Department of Physics, University of Strathclyde, Glasgow, G4 0RE, Scotland, UK *
[email protected] Abstract: Measuring fluorescence lifetimes of fast-moving cells or particles have broad applications in biomedical sciences. This paper presents a dynamic fluorescence lifetime sensing (DFLS) system based on the time-correlated single-photon counting (TCSPC) principle. It integrates a CMOS 192 × 128 single-photon avalanche diode (SPAD) array, offering an enormous photon-counting throughput without pile-up effects. We also proposed a quantized convolutional neural network (QCNN) algorithm and designed a field-programmable gate array embedded processor for fluorescence lifetime determinations. The processor uses a simple architecture, showing unparallel advantages in accuracy, analysis speed, and power consumption. It can resolve fluorescence lifetimes against disturbing noise. We evaluated the DFLS system using fluorescence dyes and fluorophore-tagged microspheres. The system can effectively measure fluorescence lifetimes within a single exposure period of the SPAD sensor, paving thewayfor portable time-resolved devices and shows potential in various applications. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License.