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Category: holograms

Programmable metasurface turns keyboard commands into dynamic holograms in milliseconds

Metasurfaces are ultrathin optical components engineered with arrays of nanoscale structures that can control light in ways that are difficult for conventional optics. Unlike traditional optical components, which typically rely on their shape and thickness, metasurfaces manipulate light using carefully designed nanostructures patterned on a flat surface.

“Active metasurfaces are extending the capabilities of flat optics by enabling optical functions to be dynamically reconfigured,” says Professor Laura Na Liu, director of the 2nd Physics Institute at the University of Stuttgart. “To tap into this potential, we need to learn how to address individual pixels within a two-dimensional metasurface at visible wavelengths.”

Researchers at the University of Stuttgart have developed an interactively addressable organic metadevice that uses electrically switchable organic materials to dynamically control light. The new platform enables every metasurface pixel to be electronically controlled independently, allowing user commands to be translated directly into dynamic holographic images.

Are We Living Inside a Hologram? | Jim Al-Khalili’s Guide To Life

Jim Al-Khalili explores the revolutionary discoveries that transformed modern physics. From Einstein’s General Theory of Relativity and the expanding universe to the bizarre world of quantum mechanics, black holes, entanglement, and the search for a Theory of Everything, this episode examines the ideas that continue to redefine our understanding of space, time, and reality itself. It concludes with one of the boldest concepts in theoretical physics—that the universe may actually be a giant hologram.

Now available on SPOTIFY! ► https://tinyurl.com/2kr4kb2d.

►Subscribe – http://goo.gl/wpc2Q1

Programmable metasurface generates dozens of holograms at once

Over the past few decades, engineers have developed various devices that can create holograms, three-dimensional (3D) or two-dimensional (2D) images produced by precisely controlling the shape and direction of traveling light waves. Holograms are now widely used to produce visual representations of objects and to measure their physical properties, authenticate documents or bank cards, and serve as visualization tools in some educational settings.

While the quality of the holograms that can be produced has improved significantly in recent years, most existing technologies can generate only one hologram at a time. To simultaneously generate several independent holograms, one would need to increase a device’s so-called holographic channels (i.e., separate streams of independently controlled holograms), which tends to reduce the quality of the produced images or the speed at which they can be refreshed.

Researchers at Southeast University in China recently developed a new programmable metasurface, an engineered ultrathin material that can manipulate waves in unique ways, which reliably generates dozens of holograms at once. This metasurface, introduced in a paper published in Nature Electronics, consists of 6,000 elements that can be individually controlled, both in terms of their spatial arrangement and how they change over time.

Optical meta‑conveyors enable programmable nanomanipulation along arbitrary open paths

The task of gently transporting a microscopic particle from one point to another along a winding path, and then bringing it back using nothing more than a single, compact chip is a challenge we set out to address in our new study, now published in Nature Communications.

Optical forces arising from momentum exchange during light–matter interactions have become indispensable tools in biophysics, soft matter science and micro-and nanofabrication. Among these, optical conveyors—capable of generating stable, directional optical flows—enable nanoparticle transport along predefined trajectories, offering unique advantages for drug delivery, cell sorting, and lab-on-a-chip systems. However, conventional platforms often rely on spatial light modulators to produce dynamic holograms. Such systems are bulky, constrained by limited pixel size and count, and difficult to integrate—factors that severely impede practical deployment.

Metasurfaces have recently opened new pathways for miniaturizing optical manipulation devices, thanks to their subwavelength field-shaping capabilities. Yet, most existing metasurface-based schemes still depend on radially or azimuthally uniform phase gradients, which confine the resulting optical flow to closed loops (vortex rings) due to the intrinsic geometry of vortex fields.

Hologram technology where ‘light becomes the key’ enables hard-to-copy security

A new type of hologram technology has been developed that uses the motion of light as a key, revealing information only under specific conditions. This is gaining attention as a novel approach that can simultaneously overcome the limitations of existing optical communication and security technologies.

Chiral metasurfaces guide twisted light into free space

Light can carry angular momentum in two distinct ways. One comes from polarization, which describes how the electric field rotates. The other comes from the shape of the wavefront itself, which can twist like a corkscrew as it travels. This second form, known as orbital angular momentum, has attracted wide interest because it allows light to encode information, interact with matter in new ways, and probe physical and biological systems. Despite this promise, producing well-defined twisted light in free space remains technically challenging, especially when the light originates from small or localized sources.

Recent research reported in Advanced Photonics Nexus demonstrates a route to generating twisted light beams by combining a dielectric multilayer with a patterned metallic surface. The work shows that surface-bound light waves can be converted into free-space beams with controlled angular momentum and polarization. Importantly, the approach avoids several limitations of earlier designs and points toward future integration with single-photon emitters.

Many existing methods for generating orbital angular momentum rely on reshaping a laser beam using holograms, liquid-crystal plates, or patterned films known as metasurfaces. While effective for large, externally illuminated beams, these approaches struggle when light must be generated directly on a chip or from nanoscale emitters such as quantum dots or single molecules. Such sources cannot uniformly illuminate a structure or arrive at a precisely defined angle, making efficient beam shaping difficult.

Unhackable metasurface holograms: Security technology can lock information with light color and distance

A research team led by Professor Junsuk Rho at POSTECH (Pohang University of Science and Technology) has developed a secure hologram platform that operates solely based on the wavelength of light and the spacing between metasurface layers. The technology makes hacking and counterfeiting virtually impossible, and is expected to be widely adopted for security cards, anticounterfeiting, and military communications. The paper is published in the journal Advanced Functional Materials.

With a growing number of hacking incidents and data breaches, the limitations of digital security are becoming increasingly evident. No matter how sophisticated an encryption scheme is, as long as it exists as code, it is difficult to completely eliminate the risk of intrusion. Motivated by this challenge, the team proposed a new approach that uses the physical conditions of light itself as a security key.

At the core of this innovation is the “metasurface,” an ultrathin optical device that arranges microscopic structures to control light. By illuminating a metasurface, a holographic image can be reconstructed in free space. However, conventional holograms have typically been limited in that a single device could store only one piece of information.

Hologram processing method boosts 3D image depth of focus fivefold

Researchers from the University of Tartu Institute of Physics have developed a novel method for enhancing the quality of three-dimensional images by increasing the depth of focus in holograms fivefold after recording, using computational imaging techniques. The technology enables improved performance of 3D holographic microscopy under challenging imaging conditions and facilitates the study of complex biological structures.

The research results were published in the Journal of Physics: Photonics in the article “Axial resolution post-processing engineering in Fresnel incoherent correlation holography.”

One of the main limitations of conventional microscopes and 3D imaging systems is that, once an image or hologram has been recorded, its imaging properties cannot be altered. To overcome this limitation, Shivasubramanian Gopinath, a Junior Research Fellow at the University of Tartu Institute of Physics, and his colleagues have developed a new method that enables to capture a set of holograms with different focal distances at the time of acquisition, instead of a single image. These can then be computationally combined to produce a synthetic hologram that offers a much greater depth of focus than conventional approaches, and allows for post-processing of the recorded image.

New agentic AI platform accelerates advanced optics design

Stanford engineers debuted a new framework introducing computational tools and self-reflective AI assistants, potentially advancing fields like optical computing and astronomy.

Hyper-realistic holograms, next-generation sensors for autonomous robots, and slim augmented reality glasses are among the applications of metasurfaces, emerging photonic devices constructed from nanoscale building blocks.

Now, Stanford engineers have developed an AI framework that rapidly accelerates metasurface design, with potential widespread technological applications. The framework, called MetaChat, introduces new computational tools and self-reflective AI assistants, enabling rapid solving of optics-related problems. The findings were reported recently in the journal Science Advances.

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