1,721,175 research outputs found
Time of Flight 3D Imagers in CMOS Technologies
No full textThis contribution describes the research activity carried out at ITC-irst on the development of different smart pixel topologies aimed at three-dimensional (3D) vision applications exploiting the multiple-pulse indirect Time-Of-Flight (TOF) and standard direct TOF techniques
Time of Flight 3-D Imagers
No full textThis contribution describes the research activity carried out at ITC-irst on the development of different smart pixel topologies aimed at three-dimensional (3D) vision applications exploiting the multiple-pulse indirect Time-Of-Flight (TOF) and standard direct TOF techniques
Low-noise CMOS single-photon avalanche diodes with 32ns dead time
No full textThe implementation of single-photon avalanche diode detectors (SPAD) in a standard high voltage 0.7-μm CMOS technology is presented. Two different device structures, combined with integrated quenching circuits, have been fabricated and successfully tested. A novel biasing scheme is proposed allowing the reduction of afterpulsing effect and the decrease of minimum device-to-device distance. Good noise performance is obtained for the 100μm2 active area device where over 50% of the population has a dark count rate below 100cps and afterpulsing lower than 0.3% with a 4-V excess bias and a 32-ns dead time. The peak photon detection probability is about 30%, while the overall system, upper limit, for the time resolution is 144ps
A SPAD-based Pixel Linear Array for High-Speed Time-Gated Fluorescence Lifetime Imaging
No full textA monolithic 64-pixel linear array for Fluorescence Lifetime Imaging applications is presented. Each pixel includes four actively quenched Single Photon Avalanche Diodes, four gated 8-bit counters and is capable of measuring single and double exponential decays. The array has a 34% fill factor, a maximum throughput rate of 320 Mbps, and has been tested up to 40 MHz laser repetition rate. Preliminary fluorescence measurements have been performed obtaining a 6% lifetime precision in 660 μs accumulation time and a very good uniformity among the pixels
Coincidence detection of spatially correlated photon pairs with a monolithic time-resolving detector array
No full textWe demonstrate coincidence measurements of spatially entangled photons by means of a multi-pixel based detection array. The sensor, originally developed for positron emission tomography applications, is a fully digital 8×16 silicon photomultiplier array allowing not only photon counting but also per-pixel time stamping of the arrived photons with an effective resolution of 265 ps. Together with a frame rate of 500 kfps, this property exceeds the capabilities of conventional charge-coupled device cameras which have become of growing interest for the detection of transversely correlated photon pairs. The sensor is used to measure a second-order correlation function for various non-collinear configurations of entangled photons generated by spontaneous parametric down-conversion. The experimental results are compared to theory
Scannerless 3D Imaging Sensors
No full textThis contribution describes the research activity on the development of different smart pixel topologies [1-6] aimed at three-dimensional (3D) vision applications exploiting the multiple-pulse indirect Time-Of-Flight (TOF) and standard direct TOF techniques. The proposed approaches allow for the realization of scannerless laser ranging systems capable of fast collection of 3D data sets, as required in a growing number of applications like, automotive, security, surveillance and robotic guidance. Single channel approach, as well as matrix-organized sensors, will be described, facing the demanding constraints of specific applications, like the high dynamic range capability and the background immunity. Real time range (3D) and intensity (2D) imaging of non-cooperative targets, also in presence of strong background illumination, has been successfully performed in the 2m-9m range with a precision better than 5% and an accuracy of about 1
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