Confocal non-line-of-sight imaging based on the light-cone transform

Confocal non-line-of-sight imaging based on the light-cone transform

Nature 555, 7696 (2018). doi:10.1038/nature25489

Authors: Matthew O’Toole, David B. Lindell & Gordon Wetzstein
How to image objects that are hidden from a camera’s view is a problem of fundamental importance to many fields of research, with applications in robotic vision, defence, remote sensing, medical imaging and autonomous vehicles. Non-line-of-sight (NLOS) imaging at macroscopic scales has been demonstrated by scanning a visible surface with a pulsed laser and a time-resolved detector. Whereas light detection and ranging (LIDAR) systems use such measurements to recover the shape of visible objects from direct reflections, NLOS imaging reconstructs the shape and albedo of hidden objects from multiply scattered light. Despite recent advances, NLOS imaging has remained impractical owing to the prohibitive memory and processing requirements of existing reconstruction algorithms, and the extremely weak signal of multiply scattered light. Here we show that a confocal scanning procedure can address these challenges by facilitating the derivation of the light-cone transform to solve the NLOS reconstruction problem. This method requires much smaller computational and memory resources than previous reconstruction methods do and images hidden objects at unprecedented resolution. Confocal scanning also provides a sizeable increase in signal and range when imaging retroreflective o...

Source: Nature - March 5, 2018 Category: Research Authors: Matthew O ’Toole David B. Lindell Gordon Wetzstein Tags: Letter Source Type: research