MIT researchers have built, according to GizModo, a camera that can take pictures of people or objects that are hidden from view by a corner wall. SlashGear explains that it’s all done with a special camera and lasers. Digital Trends says the new technology works by combining computing power with the special properties of laser light. To help clarify how it all works, USA Today has a video provided by Nature Communications.
To be clear, the camera only works when shooting around corners. It can’t see through walls or take pictures if there is no corner for light to bounce off of. It works, GizModo explains by firing a thin laser beam at a wall that is adjacent to the intended target. That laser beam explodes into an invisible burst of photons when it hits that wall, causes photons to be scattered in virtually every direction, some of which eventually strike the intended target. When that happens, the photo bounces back hitting the wall again, where it is bounced back to the camera, which records the brightness of the photon and the time it took for it to make its journey from the camera, to the walls, the target, back again to the wall and back to the camera. A computer connected to the camera than calculates what a single point of light in a recreated image of the target would look like. Meanwhile, the camera fires again and again, up to sixty times a second. Thus, to create one exposure, which lasts slightly less than a second, thousands of laser pulses are sent resulting in millions of photons being bounced around and the camera and computer together making sense of those that return to the camera. The result, is a single still image capture of a target on the other side of a wall taken from around the corner.
Initially the new camera will likely be utilized by the Military, Digital Trends says, seeing as how they were the ones that provided the funding for the researchers at MIT. But as the technology improves, other companies will no doubt want to cash in on the new capability and will add the feature to first special cameras and then perhaps such simple devices as cell phones.
Ramesh Raskar, head of the research project says that those that have difficulty seeing in their minds how the whole thing works should try thinking of how sound bounces around a room. It’s not hard to hear someone speaking on the other side of a soundproof wall, so long as there is a corner or doorway for the sound to pass though. He says, it’s essentially the same idea.