Wall-mounted wireless charger can charge gadgets up to 33 ft

Wireless power transfer remains as exciting of a research topic as when Nikola Tesla first popularized it in 1890. Despite progress made within the last hundred years, the technology continues to rely on maintaining proximity to the power source. Now, new research published in Journal of Applied Physics proposes an innovative technique that uses an LCD-like panel to simultaneously charge multiple devices up to a range of 33 ft (10 meters).

“Our proposed system would be able to automatically and continuously charge any device anywhere within a room, making dead batteries a thing of the past.” says David Smith, a professor at Duke University and one of the authors of the paper.

Contemporary technology billing itself as “wireless charging” is wireless is not state-of-the-art innovation, but electromagnetic induction — a technique discovered nearly two-hundred years ago by the English scientists Michael Faraday. Electromagnetic induction functions by running an electric current through a coil of wire to generate a magnetic field strong enough to induce a similar current in a nearby coil placed with a phone, electric toothbrush, or electric vehicle.

Electromagnetic induction has a very short range; devices need to remain in contact—or very proximity—to the power source, which is no different than being tethered to the charging source.

According to the research paper, the key to extending range lies in constructing a TV-sized LCD panel from metamaterials, like the kind already used by Toyota to build a flat “antenna” on the roofs of experimental vehicles, and channeling higher microwave frequencies through it to devices in the room.  By tuning each cell in the metamaterial to manipulate the electromagnetic waves, the wave can be channeled from the wall-mounted panel to charge devices within the room. Best of all, the proposed system theoretically charges multiple devices at once and works at a distance of up to 33 ft, more than twice the range of the KAIST system.

A few loose ends remain before finalizing the solution. First, the electromagnetic energy source behind the panel must balance power, cost, and efficiency, and the metamaterial requires optimization to rid the beams of energy created by secondary “ghost” signals or interference. Next, the system needs sensors capable of detecting human presence, to turn off if someone walks between the panel and the device.

Source: Newatlas.com