MIT Creates Camera That “Sees” Around Corners


posted Wednesday, March 21, 2012 at 1:56 PM EDT

We Homo Sapiens are a voyeuristic lot, and between X-Ray glasses and sideways-viewing camera lenses, we have a child-like curiosity about seeing without being seen. If you remember the 1982 sci-fi thriller Blade Runner you will remember how future-cop Deckard, played by Harrison Ford, used an Esper machine that allowed him to see around corners.

Well, while Harrison Ford had to suffer with 2D images, MIT’s media lab has come up with a way to see around corners in 3D, well sort of.

MIT’s experimental lab setup was first introduced last December in a video showing it detect a burst of light traveling through a plastic bottle. The setup involves a femtosecond laser whose beam is bounced off a surface, visible to the camera, like a wall and onto an object just outside the camera’s field of view, such as a hidden mannequin.

Light bouncing off the object is reflected, weakly, back where it is recorded by a detector near the laser. The laser flashes in extremely short bursts measured in quadrillionths of a second while a detector takes its measurements in trillionths of a second.

The system measures tiny differences in the time the beam travels to come up with the distances, from which a blurry, but recognizable image is built up.

Team leader Ramesh Raska and his colleagues at MIT had to overcome the problem of walls and other not so shiny surfaces that diffuse and scatter light rather than reflect it. When diffused the light no longer carries any useful information.

While even the ultrafast laser light did scatter to some degree, enough coherent light returned to the detector for the researchers to get their measurements.

This device may not be a forerunner of Blade Runner’s Esper machine (below), but students at MIT might just find themselves having to be extra careful in their dorm rooms.