Mac peripherals including keyboards could work without needing to be recharged with a cable or have new batteries installed, as Apple has been working on a wireless power supply system capable of transmitting power to peripherals like keyboards and trackpads over short distances.
As users shift towards wireless peripherals and accessories that work over Bluetooth instead of a physical connection, more people are discovering power-related inconveniences associated with the hardware. The devices periodically run out of power, requiring users either to connect them to a cable to recharge or to replace the batteries, a process that could waste a few minutes of time if spare batteries are available for use.
While wireless charging can be one solution, by temporarily placing the keyboard or mouse on a charging pad between computing sessions, it however means that users need to remember to move the keyboard and mouse to the charging pad each time. As most people would prefer to have the keyboard in position ready for typing, it is likely users may encounter drained peripherals if they were left out after use without being placed on the pad.
In a patent application published by the US Patent and Trademark Office on Thursday, Apple's concept for a "Wireless Charging System with Radio-Frequency Antennas" attempts to solve the issue. Rather than relying on a charging coil in a device being in close proximity to a charging pad, Apple's solution instead allows for the charging to take place over a short distance, such as within a foot of the charging point.
An example of how a transmitter in the iMac could be angled to charge only nearby devices on a desk
A host device, like an iMac or display, could have cavities low down below the display that house transmitting antennas used for sending power. A secondary antenna on the receiving device, namely the keyboard or mouse, would receive the signals from the transmitter, which would be fed into rectifier circuitry and converted to a voltage that would be used to charge a battery.
Apple envisions the transmitter could take the form of a rectangular hole exposing a conductive casing, as well as the antenna, which is all covered by a transparent cover layer to protect the user. The receiving device may also have a similar cavity, or use an "inverted-F antenna," as well as protective materials.
The position on the display would make such a system ideal for charging nearby items, as it could be angled to cover an area of a desk without exposing the user directly to its transmissions. An iMac may not necessarily be limited to just one transmitter, as Apple suggests the use of one in the bottom-left and bottom-right corners, increasing the coverage area.
A pair of wireless power transmitters positioned on an iMac
Apple does file numerous patent applications with the USPTO on a weekly basis, but while it offers a clue as to where Apple's interests lie, it is not a guarantee that the concept will make an appearance in a future Apple product or service.
Wireless charging over a distance is an idea that has been explored elsewhere, in part due to how potentially useful and lucrative a system would be to the company that produces it. For example, Powercast showed off its far-field charging technology to recharge devices in December 2017, with claims it could work at quite far distances of up to 80 feet away.
Apple has also previously looked at the concept, under a 2017 patent application for "Wireless Charging and Communications System with Dual-Frequency Patch Antennas." In that filing, Apple suggests how power could be transferred over any suitable wireless communications link, including cellular and Wi-Fi, meaning the same single transmission could be used for both data and power.
In theory, this would enable Wi-Fi routers to recharge devices at a distance.