This particular device, however, hasn’t been designed with the Flickr community in mind, enabling amateur photographers to take pictures over high walls. Instead, it may be utilized by the military, once work on it is complete. It could also be useful in inaccessible locations, such as an area that’s been contaminated, or be used to build up an image of a place that’s hard to enter because of various physical obstacles.
A video by science journal Nature (check it out at the end of the article) explains that the special camera works by constructing images from light waves that are bounced off surfaces, such as walls, close to the out-of-sight object.
The camera is able to record an image every two picoseconds (a picosecond is one trillionth of a second — if you can get your head around that) so the distance that the photons traveled can be measured with extreme precision.
An algorithm processes all of the collected data, using it to construct an image of the hidden object.
“It’s this [two-picosecond] time resolution that provides the key to revealing the hidden geometry,” the Nature report says.
Ramesh Raskar, head of the Camera Culture Research Group at the MIT Media Lab that conducted the study, said, “We are all familiar with sound echoes, but we can also exploit echoes of light.”
One particular challenge the scientists had a problem overcoming was understanding information from photons that had traveled the same distance and hit the camera lens at the same position, after having bounced off different parts of the obscured scene.
“The computer overcomes this complication by comparing images generated from different laser positions, allowing likely positions for the object to be estimated,” Nature’s report explained.
The process currently takes several minutes to produce an image though the scientists believe they will eventually be able to get this down to a mere 10 seconds.