Keeping objects levitated by sound airborne despite interference

Phys.org  June 20, 2022 Researchers in the UK developed a computational technique that allows high-speed multipoint levitation even with arbitrary sound-scattering surfaces and demonstrated a volumetric display that works in the presence of any physical object. Their technique has a two-step scattering model and a simplified levitation solver, which together could achieve more than 10,000 updates per second to create volumetric images above and below static sound-scattering objects. They explained the technique achieved its speed with minimum loss in the trap quality and illustrate how it brought digital and physical content together by demonstrating mixed-reality interactive applications…read more. Open Access […]

Diffractive optical networks reconstruct holograms instantaneously without a digital computer

Phys.org  November 2, 2021 Researchers at UCLA have developed a computer-free, all-optical process for the reconstruction of holograms using diffractive networks, diffractive network is an all-optical processor composed of a set of spatially engineered diffractive surfaces that collectively compute a desired transformation of an input light field through light-matter-interaction and diffraction. The spatial features of a diffractive network are trained and optimized for a given task using deep learning in a computer. After the training is complete, the diffractive surfaces can be fabricated and assembled to form a physical network that can all-optically reconstruct an input hologram of an unknown […]