LiFi, the Tech that Wants to Replace your Router with Light Bulbs

What is LiFi?

If you’re thinking “LiFi” sounds a lot like “WiFi,” you’re right! They are both technology that lets devices access networks (like the internet) without being physically plugged in. WiFi does this using radio waves to connect your device to a WiFi router. LiFi uses the same idea, but instead of using radio waves, it uses light. Its Visual Light Communication (VLC) system uses the flashing of LED light bulbs to transmit data.

If constantly flashing lights sounds annoying, don’t worry. LED light bulbs can flash so fast that the human eye can’t pick it up. To us, it just looks like the light is shining. But to your device, the bulb is flashing like Morse code at super speed. Photoreceivers in the device pick up the flashes and convert it to data on your device.

Why LiFi is Great

Have you had issues with bad internet connection in places like hospitals or airplanes? It’s because those places have a lot of electromagnetic signals, which can interfere with radio waves. Since radio waves are what makes WiFi work, it can also affect your connection. But since LiFi doesn’t use radio waves, it doesn’t have that problem.

Since light waves are faster than radio waves, LiFi also has the potential to be much faster than WiFi. Its potential transmission speed is over 224 Gbps. To compare, WiFi’s maximum speed is about 9.6 Gbps. (If you’re curious about what kind of speeds you’re getting, you can check with our Speed Test.) At LiFi’s fastest speed, you could download twenty full-length movies in a single second. Real-world tests have put its average speed closer to 10 Gbps – but that’s still faster than WiFi’s fastest.

LiFi is energy-efficient, since you’re already using light bulbs and you don’t have to use extra electricity to power routers or modems. It’s also better for security – since light can’t go through walls, it’s easy to confine your data to a specific area and harder for outside hackers to get access. And in a LiFi-connected world, we can connect to the internet through any source of light, enabling greater availability and a more connected world.

Why We Aren’t Using Lifi

At this point you may be thinking, “If LiFi is so great, why are we still using WiFi everywhere?” And the answer is because as many opportunities as it offers, it also has some drawbacks.

One issue is coverage. The average WiFi signal can extend 105 feet (32 meters) from its router, and can go through walls and other obstacles. LiFi only works about 33 feet (10 meters) from its light bulb, and it can be blocked by walls and obstacles. The signal can also be blocked or reduced if the device is in shadow – meaning your internet won’t work as well if you have your back to the light.

LiFi also doesn’t work with the lights off. Some LiFi companies claim LED lights can be dimmed enough that you won’t realize they’re on but can still provide signal. However, the lowest brightness LiFi can currently work at is 60 lux, or about the brightness of a building’s exterior at night. That’s definitely dim, but not what most people would call “lights off.”

The final drawback is that it’s a brand new technology. Though it is being used, so far it’s only in airlines and corporations. It’s not yet available to the general public. Even if it were, you’d run into a few challenges trying to use it. The first is that to enable your home light bulbs to emit LiFi signals, you will need special wiring installed in every light socket. This would be expensive and might require entirely rewiring your house. The second is that there are currently no smartphones or computers with built-in LiFi support. If you wanted to actually use those signals, you’d need an adapter.

The Future of Internet Connectivity

The idea of transmitting data with light has been around for a while. Alexander Graham Bell even experimented with it in the 1800s, though the idea eventually lost out to the telephone. It didn’t become popular again until 2011, when Professor Harald Hass did a TED talk on the subject and coined the term “LiFi.”

There are a lot of really exciting possibilities in the technology, and it’s made many advancements since 2011. But there are still several barriers it needs to overcome in order to become the dominant way of connecting to the internet. We may one day be ditching our routers in favor of light bulbs. But for now, if you want to stay connected to the internet, you’re going to have to keep your router plugged in.