Korean engineers have learned how to charge equipment remotely — with a laser

Scientists at Sejong University in South Korea demonstrated technology for transmitting energy over a distance of up to 30 meters using infrared radiation. The maximum optical power in this case is 400 mW, and the electric power is 85 mW. This is not so much, just enough to charge a small, simple sensor, but in the future, engineers promise to increase the performance of the installation.

You won’t surprise anyone with wireless charging: many smartphones support charging using a magnetic field. But the main disadvantage of this technology is a tiny range, just a couple of centimeters. To increase the charging range, scientists used an infrared laser.

Their development consists of two elements: an indoor transmitter and a 10×10 mm receiver. In the future, such receivers can be installed in devices directly at the factory. The transmitter is an optical power source with an amplifier — it produces a beam of infrared light with a wavelength of 1,550 nanometers. This range is considered the safest for human eyes and skin.

The beam passes through air and enters a receiver with a spherical retroreflector lens. It increases the efficiency of the transmitted energy and focuses the laser on a photovoltaic cell that produces electricity. Similar systems are being tested on a larger scale as a modern alternative to power lines.

If the connection between the receiver and transmitter is broken, the system will automatically enter the power-saving mode. This will reduce the consumption of electricity when no one uses charging.

One of the advantages of such a wireless system is that there is no need to rebuild existing rooms to accommodate charging sensors. Also, infrared lasers can adjust to the position of the device, even when it moves — thanks to the spherical shape of the emitter. Other similar inventions require you to be in the same position so that charging is not interrupted.

In the future, the developers plan to improve the device and ensure the operation of several receivers from one transmitter.