A team of physicists from Germany has made a significant breakthrough that could redefine display technology in smart glasses. Led by Bert Hecht and Jens Pflaum at the University of Würzburg, the researchers have successfully miniaturized OLED technology to a previously unattainable scale.
For years, the development of smart glasses has faced a major hurdle: the display remains too bulky to go unnoticed. The team claims to have fabricated the “smallest light-emitting pixel in the world,” measuring approximately 300 by 300 nanometers. Remarkably, despite its size, this pixel achieves the brightness typical of a conventional 5 by 5 micrometer OLED pixel. If this technology can be scaled up, an entire microdisplay could be seamlessly integrated into a pair of glasses, rendering it invisible to the naked eye.
The researchers” work, published on October 22, 2025, in Science Advances, details a method for creating ultra-compact light-emitting pixels using optical antennas. The goal of the research extends beyond mere demonstration; it aims to lay the groundwork for a new generation of projection modules suitable for smart glasses and other wearable devices.
What sets this discovery apart is not solely the diminutive size of the pixel, but the intensity of light it can emit while maintaining structural integrity. The result points toward extremely high resolutions in nearly imperceptible spaces. In such a device, the panel would not be visible from the front; rather, it would function as a light source that projects images onto the lens, allowing for integration in discreet locations like the frame of glasses.
Reducing a light source to nanometric dimensions without sacrificing power is not merely a matter of miniaturization; it involves intricate material engineering. The team has demonstrated the capability to control current flow and optimize light emission in a structure with minimal room for error. This level of control signifies a new phase for OLED technology, where pixels evolve from discrete elements into optical components exhibiting antenna-like behavior.
To achieve this, the researchers completely redesigned the current flow within the pixel. Previous attempts resulted in electricity concentrating at the edges, damaging the material, similar to a lightning bolt seeking the shortest path. The team addressed this issue by introducing a thin insulating layer that prevents such leaks, allowing controlled current to pass through a minuscule central opening. This approach ensures stable emission without degrading the pixel over time.
While the prototype showcases solid operational density and stability, its external quantum efficiency currently stands at only 1%. The researchers are optimistic about improving this figure by refining organic materials and the antenna architecture. They also plan to expand the emission spectrum to include the three primary colors. Only then could this innovative technology be considered ready for the next generation of portable microdisplays.
