Edinburgh researchers have helped develop a camera system that can see around walls.
The technology can locate hidden objects with the precision of a few centimetres, and track their movements.
The system works by sending light from a laser towards a hidden object or person, which bounces off the object to send a light signal back again.
By measuring the time it takes for the light to return to the camera, it is possible to determine how far away the object is.
By recording the shape of the laser echo, the device can tell which direction it is coming from.
It takes only a second for the camera to record the light signals, so it can track a moving object.
Previous technology has been able to detect the 3D shape of static, hidden objects, but the long acquisition time required meant locating and monitoring objects was a major challenge.
Researchers at the University of Edinburgh and Heriot-Watt University are continuing to develop the technology.
They are continuing to make discoveries about how the light identifies objects, and can picture them in considerable detail.
They are also focusing on how the objects captured by the camera might be reconstructed in 3D.
Researchers designed the camera chip within the MegaFrame EU project and it was fabricated by STMicroelectronics.
The study was published in Nature Photonics.
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