LiFi, also known as “Light Fidelity” is a wireless optical networking technology, which uses light-emitting diodes (LEDs) to transmit data. In 2011, professor Harald Haas made a LiFi demonstration at the TED (Technology, Entertainment, Design) Global Talk on Visible Light Communication (VLC).
When an electrical current goes through to a LED light bulb, a stream of light (photons) emits from the lamp. LED bulbs are semiconductor devices, which means that the brightness of the light flowing through them can change at extremely high speeds. The signal is sent by modulating the light at different rates. The signal can then be received by a detector that interprets the changes in light intensity (the signal) as data. Also when the LED is ON, you transmit a digital 1, and when it is OFF, you transmit a 0.
From a laptop, the audio signal transmits through the light-emitting diode (LED) where the brightness of the light flowing through them can change at extremely high speeds. We used a solar panel as a receiver, the signal is amplified and sent as audio output in the speaker.
Video demonstrates how simple LiFi work’s.