The majority of loudspeakers use technology that needs to be able to bend freely to produce the vibration that causes sound. However, this prevents them from being installed in devices without too much space or on flat surfaces because the shock against them would prevent the vibration.
The new speaker, in the form of a thin film, produces sound with minimal distortion and it uses a fraction of the energy required to operate a traditional loudspeaker. The test model of the new loudspeaker is the size of a hand, weighs the same as a dime, and can produce high-quality sound regardless of the surface to which the layer is attached.
This new technology makes it possible to make very small vaults vibrate individually, instead of vibrating the entire material, and it also has a system of layers that protects from possible shocks without impeding its movements.
The vaults are one-sixth the thickness of a human hair and just 15 microns high. Each of these tiny domes generates sound, so researchers say it takes thousands of these tiny domes vibrating at once to produce something audible.
The team tested their speaker by setting it up on a wall of 30 centimetres from a microphone and recorded decibels. They observed that the loudspeaker can produce a high-quality sound at 66 decibels, which is equivalent to the intensity of a group of people talking very loudly, and at 86 decibels, the equivalent of the sound level of city traffic.
Due to its characteristics, the researchers believe that this device could also provide sound cancellation in noisy spaces, such as aircraft cockpits, by generating a sound of the same amplitude, but of opposite phase; this could cause the two sounds to cancel each other out. The flexible device could also be used in immersive performance, providing three-dimensional audio in a theatre. And because it is lightweight and requires so little power to operate, the speaker is ideal for application in audio devices where battery life is modest.
They have claimed that this news technology gives the speaker a high enough resonant frequency to be used efficiently in ultrasonic applications, such as imaging.
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