What is Li-Fi?
The term Li-Fi was coined by pureLiFi’s CSO, Professor Harald Haas, and refers to visible light communications (VLC) technology that delivers a high-speed, bidirectional networked, mobile communications in a similar manner as Wi-Fi. Although Li-Fi can be used to off-load data from existing Wi-Fi networks, implementations may be used to provide capacity for the greater downlink demand such that existing wireless or wired network infrastructure may be used in a complementary fashion.
VLC is the use of the visible light portion of the electromagnetic spectrum to transmit information. This is in contrast to established forms of wireless communication such as Wi-Fi which use traditional radio frequency (RF) signals to transmit data.
With VLC, data is transmitted by modulating the intensity of the light, which is then received by a photo-sensitive detector, and the light signal is demodulated into electronic form. This modulation is performed in such a way that it is not perceptible to the human eye.
VLC is a category of Optical Wireless Communications (OWC). OWC includes infra-red and ultra-violet communications as well as visible light. However, VLC is unique in that the same visible light energy used for illumination may also be used for communication.