Another awesome use of femtosecond laser: creating voxels of plasma in free space.
by Sebastian Anthony - Jul 4, 2015Researchers in Japan have created a floating 3D holographic plasma display... with haptic feedback. The system, which is being presented at SIGGRAPH 2015 next month, can render up to 200,000 voxels per second, but the physical size of the display is just 1 cubic centimetre.
The system works by way of using a femtosecond laser to turn small pockets of air (voxels) into plasma. A femtosecond laser is a laser that fires for an incredibly short period of time—on the order of one quadrillionth of a second (or one millionth of one billionth of a second, if you prefer). The laser hits an atom or molecule, causing an electron to become ionised (move to a higher energy level). Shortly after, the electron loses its extra energy in the form of a photon that is emitted as visible light.
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