Over the past few years, we’ve seen several devices that use sound waves to make small objects levitate. Now, the University of Tokyo researchers who created of one such system have taken the concept a step further, using projection-mapping to illuminate particles as they float in midair.
The idea is easier to understand once you see it, so watch the video below.
The team is able to make objects levitate by creating what are called “standing waves.” Sound waves are constantly pushing air molecules back and forth, and when you combine one with its mirror image, it’s possible to make those molecules sit perfectly still. When a small enough object gets caught in a standing wave, the force can be powerful enough to neutralize the effects of gravity.