The device has been developed by the MIT Media Lab’s Camera Culture group in collaboration with Bawendi Lab in the Department of Chemistry at MIT. A Titanium Sapphire laser pulse that lasts less than one trillionth of a second is used as a flash and the light returning from the scene is collected by the camera. However, due to very short exposure times (roughly two trillionth of a second) and a narrow field of view of the camera, the video is captured over several minutes by repeated and periodic sampling.
Dr. Raskar enlisted colleagues from Bawendi Lab in the chemistry department to modify a “streak tube,” a supersensitive piece of laboratory equipment that scans and captures light. Streak tubes are generally used to intensify streams of photons into streams of electrons. They are fast enough to record the progress of packets of laser light fired repeatedly into a bottle filled with a cloudy fluid.
Although this instrument provides data about intensity, position and wavelength, but not image, through some hardware modifications, and mathematical recontructionswere able to create a moving image, of the light traversing through the bottle
The other thing about this technique is that the instrumentprovides very narrow field of view, so for us to have a satisfactory image (or even sequence of images) the experiment has to be repeated many times.
Where did this all began? It was as said, a whimsical effort to create a method of looking arround corners, by computing the paths of the reflected light, from an inaccessible room
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