A new study has suggested it could be possible to move items in midair without touching them.
Researchers claim 3D plastic blocks can be turned into acoustic holograms to generate 3D shapes, made of sound. It's believed these shapes could function like sonic tractor beams.
The plastic blocks are complex structures made from 3D printers. When one is placed in front of an audio speaker or transducer, it scatters the soundwaves and creates complex 3D fields of sound.
It's believed the sound fields could then be made in liquid or air, and then used to push, pull or spin objects.
This has previously been considered with multiple transducers, but these acoustic holograms need only one ultrasonic transducer.
Fields created with this new technique are also around 100 times more detailed than previous techniques.
Researchers said the technique could make it possible to suspend drops of water in the air, or move silicone rubber around in water to form a pattern.
Findings from the study, published in the journal Nature, could also help develop ultrasound therapies by using sound fields to destroy unhealthy tissues and improve the resolution of ultrasonic imaging.
Scientists are now researching ways in which to use acoustic holograms to create 3D sound fields that are animated, rather than static.