Li—Fi来袭：开盏LED灯上网去

A microchipped bulb can produce data speeds of up to 150 megabits per second （Mbps）， Chi Nan， IT professor at Shanghais Fudan University said.

A one-watt LED light bulb would be enough to provide net connectivity to four computers， researchers said.

But experts told the BBC more evidence was needed to back up the claims. There are no supporting video or photos showing the technology in action.

上海复旦大学信息技术学院迟楠教授表示，一个微芯片灯泡可以产生高达150MB每秒的网速。

研究者还表示，一个1瓦的LED灯泡已经足以为四台电脑提供网络连接。

不过专家也告诉BBC记者，佐证上述说法需要更多的信息。目前还没有证实该技术成功运用的视频或照片。

Li-fi， also known as Visible Light Communications （VLC）， at these speeds would be faster and cheaper than the average Chinese broadband connection.

In 2011， Prof Harald Haas， an expert in optical wireless communications at the University of Edinburgh， demonstrated how an LED bulb equipped with signal processing technology could stream a high-definition video to a computer.

He coined the term “light fidelity” or li-fi and set up a private company， PureVLC， to exploit the technology.

In 2013， the Fraunhofer Heinrich Hertz Institute claimed that data rates of up to 1Gbit/s per LED light frequency were possible in laboratory conditions， making one bulb with three colours potentially capable of transmitting data at up to 3Gbit/s.

Li-fi promises to be cheaper and more energy-efficient than existing wireless radio systems given the ubiquity of LED bulbs and the fact that lighting infrastructure is already in place.

Visible light is part of the electromagnetic spectrum and 10，000 times bigger than the radio spectrum， affording potentially unlimited capacity. But there are drawbacks： block the light and you block the signal.

Li-Fi，光保真，又称为可见光通信（VLC），将会比中国一般的宽带网络连接速度更快，且价格更便宜。

在2011年，来自英国爱丁堡大学的光无线通信专家，哈拉尔德·哈斯教授，演示了一只配备有信息处理装置的LED灯泡是如何将高保真视频传输到电脑上的。

他创造了“光保真”这一术语，并且成立了一家私营公司PureVLC来进一步开发这种技术。

2013年，德国弗朗霍夫海因里希赫兹研究所称，在实验室环境下，一个LED灯泡的数据传送速率达到1GB每秒已经成为可能，这样一个三色的灯泡传达数据的速度将可以达到3GB每秒。

考虑到LED灯泡的普遍性，而且照明基础设施是既有的，光保真将比现有的无线广播系统更加节能，更加环保。

可见光是电磁光谱的一部分，比无线电频谱要大1万倍，因而可说具有无限的开发潜力。但是它也有弊端：遮住光源，就遮住了信号。