It’s practically axiomatic that for a device to transmit sound to you, it needs to have a speaker. But the keyword there is practically, as evidenced by emerging bone conduction audio technology that Kyocera has recently been teasing (most recently, to Engadget at the CTIA conference in New Orleans).
Typically, sound is transmitted through vibrations in the air, eventually reaching your eardrum. Bone conduction technology cuts out the middleman, in a sense, by applying vibrations directly to the user’s head. In Kyocera’s prototype, for instance, the screen itself vibrates to conduct sound. Press that screen against your cheek, or ear, or even the earmuffs covering your ear, and the screen’s vibrations will send sound waves along your facial tissues and bones, delivering those signals to your inner ear, and thence to your brain.
That sound can be conducted through our skulls is a long-understood principle; it’s the reason our voices sound different to ourselves than to other people. As far back as the 1920s, the inventor Huge Gernsback developed a so-called “osophone,” which supposedly could let people hear through their teeth. It didn’t catch on, but Gernsback’s insight led to a class of modern hearing aids that employ bone conduction. Indeed, Gernsback would have been proud to learn of a dental hearing aid that recently received approval in Europe. Its name? SoundBite.
Others have tried their hand at developing bone conduction tech, with varying degrees of success. Pegaso, for instance, developed waterproof, bone-conducting headphones for swimmers who need a music fix while doing laps. In 2009, Engadget called Motorola’s experiment in bone conduction “the best Bluetooth headset we’ve ever used.”
And indeed, many who have gone hands-on, or rather ears-on, with the technology report being impressed by the quality of sound. As alluded to above, the tech can be a real boon to people who need to wear headphones, earmuffs, or anything else over their ears for the better part of the day; simply apply the vibrating screen to the surface of what’s covering your ears, and it will still sound just about as clear as if you were holding a traditional speaker to your ear. Another major reported benefit of the technology is that it enables you to hear the person on the other side of your phone even in the midst of a crowded bar or restaurant.
Both Kyocera and KDDI (a Japanese telecommunications provider) are evidently interested in bringing this technology to your smartphone, but there’s no clear indication yet of when we might see it–or rather, hear it–in the US. When The Verge took a look at the Kyocera prototype at CES 2012, reporter Jeff Blagdon said that while the phone would be on the Japanese market this year, there weren’t plans yet to bring it stateside. You can have a look at Blagdon’s trial of that prototype below.