MiPAL beam-speaker targets audio to a single listener

Researchers at Pohang University of Science and Technology (POSTECH) have developed MiPAL, a low-cost single-element speaker that uses a front acoustic metasurface lens and rear elastic meta-units to focus sound to a single listener, suppressing lateral leakage. Covering 500 Hz to 10 kHz (over four octaves) and designed for easy 3D-printed customization, the device promises headphone-free, personalized audio in public spaces like trains, planes, and museums without creating noise pollution.