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VLC optical Wi-Fi experiment: Laser pens used to transmit data

VLC optical Wi-Fi experiment: Laser pens used to transmit dataThe humble laser pen, perennial favourite in the cat botherer’s arsenal, could one day help you get faster broadband in the home.

Research from the National Taipei University of Technology in Taiwan has shown that lasers could be used to sling data through the air over an optical Wi-Fi network that’s faster than current radio-based Wi-Fi signals.

Optical Wi-Fi, or VLC (short for ‘visible light communication’) as the report calls it was successfully trialled using cheap red and green laser pens. The team headed by Hai-Han Lu found that over short distances of 10 meters, optical Wi-Fi could support accurate data transmissions at 500Mbps.

The laser pens’ batteries were replaced with a power source which turned the lasers on and off at a rate of 500 million times a second, pointed at adaptive filters 10 meters away. Speaking to the New Scientist, Lu remarked that “hobbyists could do this at home,” mentioning that everything cost a grand total of $600 (£372).

The report states that; “LED VLC systems are recognized as creating a possible valuable addition to future generations of technology, which have the potential to use light for the purposes of advanced technical communication at high-speed surpassing that of current wireless communication systems.”

VLC Optical Wi-Fi: Data in a straight line

Presumably the report here is referring to 802.11n, which has a top bandwidth of 300Mbps. Though the proposed 802.11ac standard promises bandwidth of 1200Mbps/12Gbps, the nature of optical Wi-Fi/VLC means it could be deployed in hospitals and areas where radio signals could interfere with sensitive equipment. It wouldn’t be so great for outdoor use, but could be a viable alternative to home Wi-Fi networks.

A drawback of optical Wi-Fi means that you’ll need direct line of sight between your lasers and the detectors. In long hospital corridors this wouldn’t be a problem, but in less open-plan type homes it could be tricky.

The abstract and copies of the ‘10m/500Mbps WDM visible light communication systems’ report can be found here.

Image credit: Flickr user dmuth