Sub-nanosecond time-gated camera based on a novel current-assisted CMOS image sensor

An Overview of CMOS Photodetectors Utilizing Current-Assistance for Swift and Efficient Photo-Carrier Detection

“…Over the years, the prefix “current-assistance” has been found in an increasing number of different photonic sensors: current-assisted photonic demodulators (CAPD) for time-of-flight imaging [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ], fast time-gated current-assisted photonic samplers (CAPS) for high-precision fluorescence lifetime imaging [ 19 , 20 , 21 , 22 ], current-assisted photodetector (CAP) for optical receivers [ 23 ] and current-assisted single-photon avalanche diodes (CA-SPAD) for fast and efficient single-photon detection [ 24 , 25 ]. This review paper focusses on research performed at the Department of electronics and informatics (ETRO), Vrije Universiteit Brussel (VUB) using this “current-assistance” principle.…”

Custom lifetime phantoms for characterization and benchmarking of a new CAPS fluorescence-lifetime camera

“…The tauCAM is built around the CAPS sensor that manages in pixel gating through modulation of electric fields in the substrate. 11 A time-gated sensor can be turned on and off during specific time windows, collecting any signal generated by photons during that time or ignoring it outside that window. More specifically, the CAPS sensor collects the photoelectrons generated by the fluorescent emission incident on the active area, in the detection node in the centre of the pixel.…”

“…Any photoelectrons generated by light incident on the sensor outside this window will be discarded. More information about the working of the pixel can be found in earlier publications 4,11 .…”

“…For more precise measurements and multi-exponential decays, full decay analysis can be done at the penalty of higher acquisition times for additional windows. 4 Other publications have already demonstrated the time-gating capabilities of earlier generations sensors and hardware 11 as well as real time NIR fluorescence lifetime imaging capabilities 4 . The latest generation sensor is a 64×64-pixel sensor that contains various improvements to increase QE in the gated regime, reduced dark current and sharper instrument response function (IRF) 12 .…”

Time-gated fluorescence imaging: Advances in technology and biological applications

“…25,51,61,62 Current-assisted photonic sampler arrays combined with CMOS sensors were developed for TG detection. 63 Time-correlated single photon counting (TCSPC) technique based on SPAD or PMT detectors was used in TG imaging. 13,29,39,47 In addition, various°uorescence imaging and detection based on TG technique was also demonstrated, including°uorescence lifetime imaging (FLIM), 13,26,43,47,[64][65][66] TG F€ orster resonance energy transfer (FRET), 40,67-69 and°uorescence di®use optical tomography.…”