Single-Photon Avalanche Diodes (SPAD) are affordable photodetectors, capable to collect extremely fast low-energy events, due to their single-photon sensibility. This makes them very suitable for time-of-flight-based range imaging systems, allowing to reduce costs and power requirements, without sacrifizing much temporal resolution. In this work we describe a computational model to simulate the...

BACKGROUND Silicon single-photon avalanche diodes (Si-SPADs) are the most used devices for measuring ultra-weak optical radiant fluxes in many quantum technology fields, such as quantum optics, quantum communication, quantum computing, etc. In all these fields, the detection efficiency is the main parameter, which has to be accurately known for achieving reliable measurements. In this paper we ...

This paper reviews the state of the art of single-photon avalanche diode (SPAD) image sensors for time-resolved imaging. The focus of the paper is on pixel architectures featuring small pixel size (<25 μm) and high fill factor (>20%) as a key enabling technology for the successful implementation of high spatial resolution SPAD-based image sensors. A summary of the main CMOS SPAD implementations...

In this paper we present a time-gated single-photon avalanche diode (SPAD) array, the first of its kind to be integrated with a newly developed time-resolved laser Raman spectrometer. Time-resolved Raman spectra from various highly fluorescent minerals were successfully observed using our SPAD array; these spectra were obscured by an overwhelming fluorescence background when measured using a tr...

Single-molecule fluorescence spectroscopy of freely diffusing molecules in solution is a powerful tool used to investigate the properties of individual molecules. Single-Photon Avalanche Diodes (SPADs) are the detectors of choice for these applications. Recently a new type of SPAD detector was introduced, dubbed red-enhanced SPAD (RE-SPAD), with good sensitivity throughout the visible spectrum ...

We have successfully demonstrated video-rate CMOS single-photon avalanche diode (SPAD)-based cameras for fluorescence lifetime imaging microscopy (FLIM) by applying innovative FLIM algorithms. We also review and compare several time-domain techniques and solid-state FLIM systems, and adapt the proposed algorithms for massive CMOS SPAD-based arrays and hardware implementations. The theoretical e...

We incorporate newly developed solid-state detector technology into time-resolved laser Raman spectroscopy, demonstrating the ability to distinguish spectra from Raman and fluorescence processes. As a proof of concept, we show fluorescence rejection on highly fluorescent mineral samples willemite and spodumene using a 128×128 single-photon avalanche diode (SPAD) array with a measured photon det...

BACKGROUND After resection of long-segment Hirschsprung's disease, severe perianal dermatitis (SPAD) may occur because of high stool frequency and elevated concentrations of fecal pancreatic proteases. We investigated prospectively the effect of potato-derived protease inhibitors (PPI) on skin conditions in children with postoperative SPAD. METHODS Four children (aged 12 to 24 months) with th...