Researchers have used rapid pulses of light to transmit information at speeds of over 500 megabytes per second at the Heinrich Hertz Institute in Berlin. Dubbed Li-Fi (not to be confused with Light Fidelity) is this a viable competitor to conventional wifi ?
“At the heart of this technology is a new generation of high-brightness light-emitting diodes” says Harold Hass from the University of Edinburgh ”Very simply, if the LED is on, you transmit a digital 1, if it’s off you transmit a 0. They can be switched on and off very quickly, which gives nice opportunities for transmitting data.”
It is possible to encode data in the light by varying the rate at which the LEDs flicker on an off to give different strings of 1s and 0s. The modulation is so fast that the human eye doesn’t notice.
“There are over 14 billion light bulbs world wide, they just need to be replaced with LED ones that transmit data”.
This may solve issues such as the shortage of radio-frequency bandwidth and also allow internet where traditional radio based wireless isn’t allowed such as aircraft or hospitals. One of the shortcomings however is that it only work in direct line of sight.
More information at New Scientist