WORKSHOP PAPER
A 256 × 256 Flash-LiDAR SPAD Imager with Distributed Background Suppression and Adaptive Event Detection for Space Applications in 110nm CIS Technology
Abstract
A Flash-LiDAR single-photon avalanche diode (SPAD)-based sensor for space applications is presented. The sensor integrates a matrix of 256 × 256 interconnected pixels implementing a distributed background suppression mechanism, enabling the detection and timestamping of time- and spatial-correlated photons. The in-pixel reconfigurable logic enables short- and long-range dToF operation up to 380 m and 3 km with a timing resolution of 250 ps and 10 ns, respectively. Moreover, a flexible event detection scheme based on either the first or the last detected event allows improvement of the signal-to-noise ratio (SNR) in case of target at different distances with strong background noise, enhancing the noise rejection capability of the sensor. Preliminary experimental results in an indoor test scene demonstrate the 3D imaging capabilities of the proposed sensor with precision below 1.5 cm at 6 m distance for medium albedo target.Keywords
Flash LiDAR, CMOS image sensor, SPAD, TDC, DCR, 3D imaging, coincidence detection, background suppression,References
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