New camera system creates high-resolution 3-D images from up to a kilometer away

A standard camera takes flat, 2-D pictures. To get 3-D information, such as the distance to a far-away object, scientists can bounce a laser beam off the object and measure how long it takes the light to travel back to a detector. The technique, called time-of-flight (ToF), is already used in machine vision, navigation systems for autonomous vehicles, and other applications, but many current ToF systems have a relatively short range and struggle to image objects that do not reflect laser light well. A team of Scotland-based physicists has recently tackled these limitations and reported their findings today in the Optical Society's (OSA) open-access journal Optics Express.



The research team, led by Gerald Buller, a professor at Heriot-Watt University in Edinburgh, Scotland, describes a ToF imaging system that can gather high-resolution, 3-D information about objects that are typically very difficult to image, from up to a kilometer away.

The new system works by sweeping a low-power infrared laser beam rapidly over an object. It then records, pixel-by-pixel, the round-trip flight time of the photons in the beam as they bounce off the object and arrive back at the source. The system can resolve depth on the millimeter scale over long distances using a detector that can "count" individual photons.

EurekAlert!