Time-gating of single-photon avalanche diodes (SPADs) was commonly used as a method to reduce dark noise in biomedical imaging applications where photon events are correlated with reference clock. also obtain timing information by shifting the gate windows applied SPAD array. However, this approach, fine resolution comes at cost lengthened measurement time due large number counts required for e...

Abstract The objective of this research was to evaluate the technical feasibility SPAD index in diagnosis N status ‘Esmeralda’ peach. field trial, with five rates applied soil (0, 40, 80, 120 and 160 kg ha-1 as urea form) conducted a randomized block design four replications. During years 2014, 2015, 2016 2017, readings were carried out Minolta SPAD-502 chlorophyll meter, leaf middle part, 40 l...

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...

3D imaging based on single-photon avalanche diode (SPAD) arrays is of interest in many applications. Limited by the small array size and low fill-factor available SPAD array, it difficult for array-based lidars to achieve high-resolution high-quality images currently. Here, we propose a sub-pixel continuously scanning panoramic method. This method uses increase spatial resolution employs accumu...

The nonlinear distortion introduced by the dead time strongly limits throughput of highly sensitive SPAD-based optical wireless communication (OWC) systems. Optical OFDM can be employed in systems with SPAD arrays to improve spectral efficiency. In this work, a theoretical performance analysis OWC system asymmetrically-clipped (ACO-OFDM) is presented. impact nonlinearity on investigated. additi...

We present a new environmental application of SPAD imagers, namely the continuous and real-time measurement of size and shapes of hydrometeors. Details of the set-up and results obtained with a first 32x32 pixel prototype based on the RADHARD2 chip [1] are illustrated. Real-time operation at very low light levels, 6000 frames per second and 1:100 average data reduction are amongst the most sign...