3D-Printed 'Lego' Bricks Could Bend Sound into Acoustic Holograms

3D-printed bricks that look like Lego pieces could provide a simple, low-cost way of creating acoustic holograms — 3D shapes and structures made of sound — for applications as varied as entertainment, medicine or wireless charging, according to a recent study. Anyone who's watched "Star Wars" will be familiar with the concept of an optical hologram — a 3D image that floats in midair — though real-life technology is significantly less advanced than what was portrayed on-sc