Lidar beam

Single particles of light can be used for remote 3D surveillance

A beam of light can scan distant objects one photon at a time

Science History Images / Alamy

Taking really detailed 3D images from afar can be difficult without multiple cameras, but it is possible using individual particles of light, called photons. A team of researchers have now quadrupled the range of this technique, perhaps paving the way for creating such images from aeroplanes.

Feihu Xu at the University of Science and Technology of China and his colleagues used an existing single-photon version of a method called lidar, which stands for light detection and ranging, to take their images. …