Researchers at Scotland’s Heriot-Watt University have demonstrated a compact, non-line-of-sight laser ranging technology that relies on the ability to send light around an obstacle using a scattering floor and then detect the return signal from a hidden object within only a few seconds of acquisition time. By detecting this signal with a single-photon avalanche diode (SPAD) camera, the researchers can follow the movement of an object located a meter away from the camera with centimeter precision. Their prototype camera system allows the object’s position behind the wall to be localized to within a centimeter or two, and by making measurements every few seconds the camera can also detect the speed of a moving object. In contrast to previous methods, which required long data processing times, the new method can track moving objects in real time. The camera is currently limited to locating objects up to 60cm away from a virtual mirror on the floor, but this should improve to around ten meters, as well as to more closely detect the shapes of hidden objects as well as their positions.