Gagan jain has built an interesting rig called the Lifi, it allows a simple transmission of audio using an LED for sending the audio signal and a solar cell to receive it.

“The full form of LiFi is Light Fidelity. LiFi basically is a Wireless Communication Technology which uses Visible Light for Data transmission. LiFi is designed to use LED Light Bulbs similar to those present in our homes and offices. However, there is a slight difference in these LiFi LED Light Bulbs and Normal LED Light Bulbs . These LiFi LED Light Bulbs transmit Data through the Light given off by them and these Light Signals are received by Photoreceptors.”