Up to now, a couple of methods have been studied to transfer power over long ranges wirelessly; however, it wasn’t that easy to send enough power in a safe way. Therefore the researchers worked on a novel method called distributed laser charging. According to the press release, this method provides safe high-power illumination with less light loss.
Distributed laser charging works almost like traditional lasers; however, the optical components of the laser cavity are not integrated into one device but are separated into a transmitter and receiver.
When two are in the line of sight, a laser cavity is created between the transmitter and receiver over the air. This allows the system to deliver light-based power. When a barrier cuts the transmitter-receiver line of sight, the system switches to power-safe mode and maintains hazard-free power delivery in the air.
While developing the new system, researchers used an erbium-doped fiber amplifier optical power source with a central wavelength of 1550 nm. This wavelength is harmless to human eyes or skin at the power used as it’s at a safe point on the spectrum.
“While most other approaches require the receiving device to be in a special charging cradle or to be stationary, distributed laser charging enables self-alignment without tracking processes as long as the transmitter and receiver are in the line of sight of each other,” said Ha. “It also automatically shifts to a safe low power delivery mode if an object or a person blocks the line of sight.”