Internet via light or how does Li-Fi work?

Imagine connecting to the internet just by turning on a lamp in your living room. It sounds like an idea from a sci-fi movie, but Li-Fi technology makes it a reality. This internet via light offers a new form of wireless communication that can complement or in some cases even replace traditional Wi-Fi.

As the number of connected devices grows, developers are seeking faster and more reliable solutions. Li-Fi promises the transmission of large volumes of data with minimal delay and without overloaded channels.

Initial tests show that Li-Fi could soon find its place in everyday life, such as in hospitals, airplanes, or smart buildings, where reliable connectivity is crucial. In this article, we'll explore what Li-Fi is, how it works, how it differs from Wi-Fi, where it's already being tested, and the advantages and limitations of data transmission via light.

What is Li-Fi and how does it work

The abbreviation Li-Fi stands for Light Fidelity and refers to technology that uses light to transmit data. Instead of radio waves, which Wi-Fi operates on, Li-Fi technology uses light signals transmitted through LED sources. Each such lamp can serve not only for lighting but also as a miniature internet transmitter.

The principle of Li-Fi connectivity is simple. LED light blinks at extremely rapid intervals that are unnoticed by the human eye, but a special receiver reads them as binary code, i.e., zeros and ones. It is a modern version of Morse code at significantly faster speeds. The received pulses are converted back into digital data, enabling internet access.

The concept was popularized by German physicist Harald Haas, who, with his team, demonstrated at the beginning of the 21st century that light could be used for two-way data transmission. Since then, the development of Li-Fi technology has progressed, and more teams and companies are looking for ways to bring it from laboratories into everyday life.

Li-Fi vs Wi-Fi - Where does internet via light have the upper hand

Li-Fi technology takes wireless connectivity to a new level. In lab tests, it achieved speeds exceeding 224 gigabits per second, which in practice means the ability to download multiple 4K resolution movies in seconds. Lower latency improves streaming, online gaming, and working with large data.

A strong argument is also security. The light signal remains within the illuminated area and doesn't penetrate walls or windows, making it difficult to intercept from outside. Therefore, Li-Fi technology is suitable for environments with sensitive information, such as healthcare, industry, or government institutions.

Since Li-Fi doesn't use radio frequencies, it doesn't interfere with other wireless networks. It works reliably even where Wi-Fi struggles with reliability, such as at airports or office centers.

Where is internet via light already being tested and used

Although Li-Fi is still developing, its practical use is taking shape. The most significant progress can currently be seen in Europe, where internet via light is being tested in various environments and regular operations.

One of the pioneers is the French company Oledcomm, which has been working on Li-Fi systems since 2008. Their solutions use light signals to transmit data and are being tested in offices, hospitals, and transportation. The goal is to verify how Li-Fi can complement or speed up existing networks in practice.

A research milestone came in 2024, when during the Ariane 6 mission, experiments with light data transmission in space were conducted. It showed that light transmission can work even where traditional radio connections hit their limits.

Companies such as The LiFi Group, pureLiFi, and Signify are involved in development, having introduced the first commercial solutions. Among them is the Trulifi 6002 system, which combines light transmission with low latency and enables video calls, streaming, or gaming without interruption. Although it's primarily intended for corporate environments, it demonstrates how light internet can work in practice.

This type of connection finds applications in areas where security and stability are key. It is used in military communications, aviation, the automotive industry, and government organizations. In the United States, projects are developing that explore how to integrate the Li-Fi principle into smart city infrastructure.

Does internet via light have any limitations?

As with any new technology, there are obstacles to widespread adoption of Li-Fi. The main issue is that light signals behave differently than radio waves. To transmit data, devices must be in direct line of sight of the light. Once an obstacle, such as a wall or furniture, comes between the source and receiver, the connection is interrupted.

Main Li-Fi limitations:

• Limited range. Light doesn't pass through solid objects, so the connection works only within a single room.
• Dependence on light. Transmission is only possible with the light on, which limits use at night or outdoors.
• Costs and compatibility. Current Li-Fi devices are expensive and not widely available.
• Lack of mobile connectivity. Moving between rooms interrupts the connection, complicating regular home use.

Although it is a technology with great potential, Li-Fi currently makes the most sense in situations where light is used continuously.

What to expect from Li-Fi in the coming years

The development of Li-Fi technology is rapidly moving from laboratories to real-world deployment. Experts expect the first broader commercial solutions to appear on the market between 2024 and 2029. The technology will first establish itself where security and stable transmission of large amounts of data are crucial.

Manufacturers are also preparing new systems that handle fast connections with low latency and are gradually approaching regular use. Device costs are currently higher than traditional Wi-Fi, but with increasing interest from institutions and companies, prices are expected to decrease.

Internet via light is already appearing in smart city pilot projects, helping to transmit data between sensors and infrastructure. In the future, it could complement existing networks where radio waves face limits or cause interference.

Although Li-Fi connectivity is still in the testing phase, its development is heading towards broader deployment over the coming years. Once technical obstacles are overcome and compatible devices are more widespread, light internet could become a standard part of modern offices, buildings, and homes.