Multimodal Acoustic Trap Display (MATD)

A volumetric display powered by soundwaves creates tactile 3D virtual designs in mid-air. In order to generate tactile virtual images, an acoustic levitation process uses ultrasound to trap lightweight objects, such as a small 1-2 mm polystyrene bead, inside a box surrounded by an array of speakers. The speakers' acoustic signals then move the beads at considerable speed while illuminating them with red, green, and blue lights, creating 3D shapes.

The MATD uses the pressure delivered by ultrasound to create high-pressure points that emulate touch. The image later passes through a secondary trap mounted on time-division multiplexing (TDM), which generates simultaneous auditive and tactile content.