Scientists at M.I.T Media Lab, through the use of an ultrafast imaging system, have discovered a new way to capture light lassing through liquid and objects by recording an image in less than two-trillionths of a second. The project has a long and storied history detailed by John Markoff in yesterday’s New York Times, in which the author discusses how light is captured in a sort of “super slow motion:”
The streak tube scans and captures light in much the same way a cathode ray tube emits and paints an image on the inside of a computer monitor. Each horizontal line is exposed for just 1.71 picoseconds, or trillionths of a second, Dr. Raskar said – enough time for the laser beam to travel less than half a millimeter through the fluid inside the bottle.
To create a movie of the event, the researchers record about 500 frames in just under a nanosecond, or a billionth of a second. Because each individual movie has a very narrow field of view, they repeat the process a number of times, scanning it vertically to build a complete scene that shows the beam moving from one end of the bottle, bouncing off the cap and then scattering back through the fluid. If a bullet were tracked in the same fashion moving through the same fluid, the resulting movie would last three years.
“Imagine if you have this in your phone about 10 years from now,” Dr. Raskar said. “You will be able to go to your supermarket and tell if your fruit is ripe.” Videogame hardware may soon be able to read our lips and eventually our minds, and the possibilities for dynamic environmental interaction here are endless. But let’s not get ahead of ourselves. “We’re still trying to get our heads around what this means,” Dr. Raskar said, “because no one has been able to see the world in this way before.”