LEDs could multitask as data transmitters

Guardian : Light bulbs could soon be used to broadcast wireless internet. Harald Haas of the UK’s Edinburgh University has been working on a revolutionary method of data transmission that makes use of light waves rather than wires or radio waves. Using LEDs, which are more efficient than standard light bulbs and can be switched on and off very quickly, he has found that he can vary the intensity of their output and pick up the signals with a simple receiver. With data rates of 100 megabits per second, Haas’s system relies on the fact that the human eye cannot detect the rapid flickering on and off of the LEDs—instead they appear to maintain a normal steady glow. Besides faster transmission capabilities, such a device would also have applications in the oil and gas industries, where radio waves can cause sparks, and for underwater robotic vehicles and submarines, where the electrically conductive salt water stifles radio waves.