Photometrically optimized event-based stereo 3D measurements

Event cameras only report changes in brightness when thresholds in individual pixels relative to previous levels are crossed. They output sparse streams of events that quantify these changes spatially and temporally. We have developed a measurement system using two event cameras in a stereo configuration with a specialized projector for 3D measurements of static objects. We show that optimal contrast in the structured illumination yields high-fidelity measurements, reaching 3D root-mean-square deviations of 0.6 mm (≈0.3<i>%</i> of the measurement volume's diagonal). This work opens up the possibility of precise event-based, highly dynamic 4D measurements in the near future.