Traditional headphones, including the popular AirPods and AirPods Pro, use – in simple terms – small speakers to transmit the sound of an iPhone or iPad to the wearer’s ear. In a new document, Apple describes how to lift the limitations associated with this technology.
AirPods of the future: Apple describes the use of bone conduction
The current AirPods, whether Pro or not, are plugged directly into the ear like all normal earphones and transmit the sound to the wearer via sound waves. As Apple’s engineers describe in a patent discovered by AppleInsider, the iPhone manufacturer could rely on the use of so-called bone conduction in the future. This technique is known as “bone conduction” in English.
Instead of sound waves, this technology uses vibrations on the skull bones to transmit sounds. This technique is already used in some cases where classic earphones cannot be used. This is the case, for example, when a user only has limited hearing. Such headphones with bone conduction can also be used, for example, under water. At the same time, the normal ear canal can remain free so that the wearer can continue to hear his surroundings as usual.
One problem with “bone conduction” is the restricted frequency range. If humans can normally hear frequencies in the range of 20 to 20,000 Hertz, bone conduction can only be used effectively up to 4,000 Hz. In addition, there is the necessary contact with the head, which could be annoying for many users.
In Apple’s patent, the engineers describe a mixture of classic technology that uses sound waves and bone conduction. To counteract the limited frequency range, Apple’s system separates the signals into three areas, for example. The low and medium frequency ranges are combined and transmitted via the bones. On the other hand, a classic system that uses sound waves is used to transmit the high frequencies – a loudspeaker. Apple’s drawings suggest that these “earphones” do not close the ear canal.
Apple AirPods Pro compared to the competition:
Not just for AirPods: possible use with Apple Glass?
Such a technology could not only be used in future AirPods, but might also be interesting in combination with the AR glasses, which are often rumored – often called Apple Glass. In the future, the contact of the bracket with the head may be enough to transmit notifications or other sounds to the wearer – possibly without the use of classic speakers.
As is customary with such patents, these do not necessarily indicate future devices that actually use the techniques described. Apple filed this patent on May 25, 2018. Before that, however, there was already evidence in 2014 and 2015 that the company from California was researching such technologies.