Battery empty? This laser charges smartphones from 30 meters away
Researchers from South Korea have developed a laser that can be used to charge mobile devices such as smartphones wirelessly – from a distance of up to 30 meters. All that is required is a line of sight.
Charging mobile devices has become easier and easier in recent years. While two decades ago every cell phone still had its own charging cable, we have now (almost) completely switched to USB Type-C or Lightning connectors. Many devices can also be charged wirelessly.
Researchers from Sejong University in South Korea have now further developed this technology. To do this, they designed a method with which mobile devices can be charged wirelessly over a distance of up to 30 meters. Café operators could, for example, supply their customers’ smartphones with electricity via a system in the ceiling. But how does it work?
Wireless charging: Power transmission via laser can be dangerous
So far, the technology is not fully convincing. One of the main reasons is that the transmission of energy by laser must be visible. This poses a potential danger to us humans.
The laser beams would not inflict any direct injuries on us. In theory, however, the radiation could lead to cell mutations and, as a result, to cancer. However, the new system from South Korea is convincing because it makes use of the properties of infrared light.
In the first test setups, around 400 milliwatts could be transmitted over a distance of 30 meters. Although this is not enough to charge a smartphone, it is a first step forward.
New technology relies on line of sight between transmitter and receiver
Again, the new method poses no risk, as the line of sight between the device and the laser from which the energy comes shuts off as soon as it is broken. In addition, the laser only transmits at a wavelength of 1,550 nanometers, which is considered particularly safe.
In the next step, the researchers want to charge mobile devices wirelessly. Then maybe one day the technology could become part of our everyday life. Then smartphones and the like would charge themselves in a café without any action, so to speak.
Also interesting:
