A videograb shows the sonic tweezers levitate small objects.

Gulf Today Report

Japanese engineers developed a new way to levitate small objects using sound waves after discovering how to pick up objects from reflective surfaces using sonic levitation.

Objects can be dealt with without touching, using a technology called “Sonic Tweezers” which uses a laser to generate enough radiation pressure to lift and move extremely small particles.

Sonic tweezers, where pressure generated by sound waves can be used to move particles, can be used to process a wider range of materials with sizes even larger than the millimetre scale.

Although they were first discovered in the 1980s, there are limitations to the use of sonic tweezers in wide practical applications.

These tweezers need to create an appropriate sound field to lift an object and move it away. It becomes more difficult if there is a reflective surface.

A graphic illustration shows the dimensions of sonic tweezers.

Engineers Shota Kondo and Kan Okubo of Tokyo Metropolitan University in Japan discovered how to build a hemispherical acoustic array which can lift a polystyrene ball 3 mm in diameter from a reflective surface.

In their paper, they wrote: "We propose an array of multi-channel hemispherical ultrasonic transducers to pick up objects without touching them."

The research was published in the Japanese Journal of Applied Physics.