Single photon detectors sensitive to near-infrared (NIR) wavelength light are used in an increasing number of applications, such as quantum key distribution, laser detection and ranging, and integrated circuit analysis. There are many types of NIR single photon detectors, e.g. photomultiplier tube, superconducting single photon detector and single photon avalanche diode (SPAD). However, the SPA...

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 approxima...

We present a single-photon avalanche diode (SPAD) with a wide spectral range fabricated in an advanced 180 nm CMOS process. The realized SPAD achieves 20 % photon detection probability (PDP) for wavelengths ranging from 440 nm to 820 nm at an excess bias of 4 V, with 30 % PDP at wavelengths from 520 nm to 720 nm. Dark count rates (DCR) are at most 5 kHz, which is 30 Hz/μm2, at an excess bias of...

Advances in SPAD sensor technology have recently yielded a >10kfps, 320x240 resolution imager [1] that can be operated as a Quanta Image Sensor (QIS) [2]. This device (labelled SPCImager) thus combines the high speed and sensitivity afforded by SPAD devices with the negligible readout noise and logarithmic compression of QIS. These attributes open the door to a number of potential applications ...

The state (type, structure and biochemical content or vitality) of natural and agroecosystems are influenced by several factors including available nutrients, soil types, and topographic and climatic factors. In other words, foliar biochemicals (e.g. chlorophyll, Nitrogen) for example may provide information on the factors controlling growth and productivity of ecosystems. However, the quantifi...

Now, more than at any other time in the history of the railways, there is an urgent need for the industry to learn lessons from near misses and incidents. In this first of two articles, we examine the extent to which the current procedures for gathering data on accidents such as SPADs provide support for the identification of underlying causes. An alternative approach is outlined, which we beli...

A complete module for single-photon counting and timing is demonstrated in a single chip. Features comparable with or better than commercially available macroscopic modules are obtained by integration of an active-quenching and active-reset circuit in complementary metal-oxide semiconductor technology together with a single-photon avalanche diode (SPAD). The integrated SPAD has a 12-microm-diam...

The first single-photon avalanche diode (SPAD) image sensor fully integrated on flexible substrate is reported. The design consists of an array of 1024 quenched pixels with CMOS readout and addressing circuitries. The flexible substrate was made compatible with sol-gel polymer, which will be used to imprint microlenses by quartz mold to improve fill factor. The SPAD pixel can operate both in fr...

We present a resonant-cavity-enhanced Single Photon Avalanche Diode (SPAD) fabricated on a reflecting siliconon-insulator (SOI) substrate. The substrate incorporates a two period distributed Bragg reflector fabricated using a commercially available double-SOI process. The resonant-cavity-enhanced (RCE) SPAD detectors have peak photon detection efficiencies ranging from 41% at 780nm to 32% at 85...