Always forget to charge your phone? Laser technology that emits electricity wirelessly from 100 feet away could automatically charge your devices when you enter a room
- A new charging system could transmit power to devices up to 100 feet away
- A transmitter beams infrared light to a receiver, which converts it into electricity
- The receiver could be attached to smartphones to enable remote charging
- To make this possible, the engineers are still working on increasing the efficiency of the system
Waking up to find your phone hasn’t charged overnight can put a damper on the day ahead.
But what if you didn’t have to think about connecting your devices because a laser beam did it automatically for you?
Researchers at Sejong University in North Korea have developed a new charging system that uses infrared (IR) light to transmit power to electronics up to 30m away.
They hope the discovery could lead to technology that automatically charges a phone the moment it’s brought into a room, including public places like airports and supermarkets.
The leader of the research team and associate professor Dr. Jinyong Ha said, “The ability to wirelessly power devices could eliminate the need to carry around power cords for our phones or tablets.
“It could also power various sensors, such as those in Internet of Things (IoT) devices and sensors used to monitor processes in manufacturing plants.”
Researchers at Sejong University in North Korea have developed a new charging system that uses infrared (IR) light to transmit power to electronics up to 30m away. They hope the discovery could lead to technology that automatically charges a phone as soon as it’s brought into a room
The system includes a transmitter with an optical amplifier power source that produces infrared light and a receiver with a spherical lens that can pick up rays from any direction
HOW DOES THE CHARGER WORK?
The new charger is described as a “distributed laser charging system”.
This means that it consists of a transmitter and a receiver.
The transmitter generates a beam of IR radiation from an optical amplifier.
This is absorbed by a photovoltaic cell on the 0.4 square inch (10 square millimeter) receiver attached to an electronic device.
The cell can convert the light energy into electricity to power the device, and the receiver’s spherical lens also allows it to pick up incoming rays from any direction.
While wireless charging is already a feature of many new devices, it is often necessary to place the device on a dock or special surface so that it cannot be moved far while charging.
Engineers are working to eliminate these needs and allow energy to be transmitted over longer distances, but this often requires bulky and complex equipment.
The study, published yesterday in Optics Express, describes a “distributed laser loading system” that consists of just two kits; a transmitter and a receiver.
The emitter generates an IR beam from an optical amplifier and can be connected to a power source in a room.
The light has a ‘safe’ central wavelength of 1550nm and passes through a filter to produce a beam that at the power used poses no risk to human eyes or skin.
The 0.4 x 0.4 inch (10 x 10 mm) receiver has a photovoltaic cell that can absorb this light and generate electricity and can be attached to everyday electronics.
The receiver’s spherical lens also allows it to take incoming rays from any direction and focus them onto a point at its center.
This means the transmitter does not have to track or lock on to the receiver.
“While most other approaches require the receiving device to be in a dedicated charging cradle or to be stationary, distributed laser charging allows for self-alignment without tracking processes as long as the transmitter and receiver are in line of sight of each other,” he told Dr Ha.
If something blocks the line of sight between the transmitter and receiver, it automatically switches to “safe energy transfer mode” and reduces the intensity of the beam.
The transmitter generates a beam of IR radiation from an optical amplifier (EDFA) that can reach the photovoltaic cell on the receiver over 30 m away. PD: Photodiode (LED), PV: Photovoltaic
Effect of increasing the transmitter-receiver distance on the optical power absorbed by the receiver (black) and the electrical power into which it is converted (red). MPE = maximum allowable exposure limit
During the test, the team was able to transmit a 400 mW beam of light over a distance of 30 m (100 feet), which was converted into 85 mW of electrical power.
This would realistically only be enough power to power a small sensor, let alone a smartphone, but it’s hoped it can scale in the future.
The team is currently working to improve the efficiency of the photovoltaic cell in the receiver so that it can convert more of the beam’s energy into electricity.
They’re also interested in finding ways to charge multiple devices at the same time.
dr Ha said, “Using the laser charging system to replace power cords in factories could save maintenance and replacement costs.”
“This could be particularly useful in harsh environments where electrical connections can cause interference or pose a fire hazard.”
USB-C chargers will be mandatory for all phones sold in the EU by 2024 – but not the UK
Apple must change the connector on iPhones sold in the European Union (EU) by 2024 under its new rules.
The rule, announced in June, means Apple will have to change the charging connector on its iPhones in all 27 EU countries.
Currently, iPhones use Apple’s proprietary “Lightning” power connector technology, while Android-based devices use USB-C connectors.
The EU wants a single charging cable for smartphones and other devices to reduce e-waste, but Apple argues that this would limit innovation and hurt consumers.
However, a UK government spokesman told Web: “We are not considering repeating this requirement at this time.”
Northern Ireland has to comply with the rule due to the current post-Brexit regulations – namely the Northern Ireland Protocol.
The union estimates that discarded or unused chargers account for 11,000 tonnes of e-waste in Europe every year.
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