What is Li-Fi, and could light replace WiFi?

The answer

Li-Fi (Light Fidelity) transmits data by modulating LED light at frequencies imperceptible to the human eye, using the visible light spectrum (400–800 THz) instead of radio frequencies. Coined by University of Edinburgh professor Harald Haas in a 2011 TED Talk, Li-Fi has achieved speeds exceeding 224 Gbps in laboratory conditions - over 100 times faster than typical WiFi. In 2023, Fraunhofer HHI demonstrated 1 Gbps commercial Li-Fi systems. PureLiFi, the leading commercial provider, launched its Light Antenna Module in 2023 for integration into laptops and smartphones. Advantages include zero electromagnetic interference (critical in hospitals and aircraft), enhanced security (light doesn't penetrate walls), and utilizing the visible spectrum, which is 2,600 times larger than the entire radio spectrum. The IEEE 802.11bb standard for Li-Fi was published in 2023, enabling integration with existing WiFi infrastructure. Limitations include the requirement for line-of-sight and poor outdoor performance in sunlight.