US researchers have developed a camera that can effectively see around corners by bouncing a laser beam off walls and other surfaces.
The technology, developed at the Massachusetts Institute of Technology (MIT), emits tiny bursts of light and measures how long it takes for them to be reflected back to a detector, using this to calculate how far they’ve travelled and to build up a picture of the space.
This research, published this week in the journal Nature Communications, could eventually lead to imaging systems that allow emergency teams to assess dangerous environments or vehicle navigation systems that can handle blind turns.
The system, which first appeared as a prototype in 2010, works by firing several pulses of light at different angles into the space being scanned and compares the times at which the returning light strikes different parts of the detector to piece together a picture of the area’s geometry.
It uses a femtosecond laser to emit bursts of light measured in quadrillionths of a second and measures the returning pulses with a detector every few picoseconds, or trillionths of a second, to calculate their time of flight.
The researchers, led by MIT Media Lab associate professor Ramesh Raskar, used the system to produce recognisable 3D images of a wooden figurine and foam cut-outs outside their camera’s line of sight.
Femtosecond lasers have previously been used to produce extremely high-speed images of biochemical processes in a laboratory, where the trajectories of the laser pulses were carefully controlled.
As well as allowing emergency response teams to check whether a room is safe before entering it, the technology could also be used with endoscopic medical devices to produce images of parts of the body that are difficult to reach with internal cameras.