A Fully Integrated dToF System-on-Chip with High Precision Using Adaptive Optical Power Control and Shifted Histogram-Bin Binning

Abstract

This paper demonstrates a ranging sensor system with a configurable array of $16 \times 16$ single photon avalanche diodes (SPADs), a 940nm vertical cavity surface-emitting laser (VCSEL), a co-design VCSEL driver with tunable widths from 400ps to 3630ps full-width at half-maximum (FWHM) optical pulses and peak power from 30mW to 170mW, and an embedded core to implement adaptive optical power control and distance extraction. An adaptive optical power control and a shifted bins binning of the histogram (SBbH) method to achieve high-precision distance measurement both at short-range and long-range. We achieved a minimum distance of 20mm with an absolute error better than 20% (4mm), still with a precision better than 10mm at 7m. All of results are obtained with 80% reflectivity of target at 100 frame rate.