Sound Tweezers Image
The method splits the hemispherical array into manageable blocks and uses an inverse filter that finds the best phase and amplitude to drive them to make a single trap at some distance from the transducers themselves.

Researchers from Tokyo Metropolitan University developed a method that allows non-contact manipulation of small objects using sound waves.

The technique uses a hemispherical array of transducers. The researchers split the array into manageable blocks and used an inverse filter that finds the best phase and amplitude to drive them to make a single trap at some distance from the transducers themselves. By adjusting how they drive the blocks over time, they can change the position of their target field and move the particle they have trapped.

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