3D-Printed Acoustic Holograms Could Move Objects in Midair

3D-printed plastic blocks can now be turned into acoustic holograms that generate 3D shapes made of sound, which could function like sonic "tractor beams," according to a new study. This finding could also help scientists develop ultrasound therapies with sound fields sculpted to destroy unhealthy tissues in the body while leaving neighboring healthy cells intact, the researchers added. The pixels making up each hologram scatter light falling onto them in very specific ways, causing these light