Developed at Julius-Maximilians-Universität Würzburg, this nano-pixel is bright enough to rival traditional OLED displays, despite being more than 100 times smaller. The results mark a step toward ultra-compact projection systems for AR and VR.
Wearable technology, especially smart glasses, has long promised to deliver immersive digital experiences without bulky hardware. But pixel miniaturization has hit physical limits, particularly when shrinking light sources below the size of a single wavelength. The breakthrough by the Würzburg-based team overcomes this barrier by using nanoscale optical antennas that both emit and amplify light. These structures achieve brightness comparable to conventional displays, without the size burden.
With smart eyewear seen as a key pillar of future consumer tech, the development of such miniaturized displays may finally unlock practical, lightweight designs. The scientists behind the work believe this approach could fit a full HD display on a one-square-millimeter surface—small enough to integrate directly into glasses.
Nanoscale Engineering Reshapes Light Emission
The project was led by Professors Jens Pflaum and Bert Hecht, whose team engineered the pixel using an organic light-emitting diode (OLED) coupled with a metallic antenna structure. As Hecht explains, the final structure measures 300 by 300 nanometers—a surface area about the size of a single bacterium. Yet, this tiny device emits orange light as brightly as a conventional 5 by 5 micrometer OLED pixel.
The antenna design is key. Constructed from gold in a cuboid form, it serves as a contact point for electrical current while also enhancing the light output. The OLED stack, like its larger counterparts, contains thin organic layers sandwiched between two electrodes. When current flows through, it excites the molecules, producing light directly without needing backlighting.
According to SciTechDaily, this eliminates one of the biggest roadblocks in miniaturization: energy inefficiency and weak brightness in extremely small pixels. With this configuration, even a full 1920 x 1080 resolution could theoretically be compressed into a display smaller than a grain of sand.
Insulation Layer Solves Current Instability
One of the biggest technical challenges the team faced was controlling current flow in such confined dimensions. Pflaum notes that reducing the size of an OLED doesn’t work by default: “As with a lightning rod, simply reducing the size of the established OLED concept would cause the currents to emit mainly from the corners of the antenna.”
These strong localized fields tend to create unwanted effects, such as mobile gold atoms migrating into the active material and eventually short-circuiting the pixel. To prevent this, the team added a precision-engineered insulating layer. This layer, placed on top of the antenna, leaves only a 200-nanometer-wide circular aperture at the center—blocking current from the edges and stabilizing emission.
This setup allows the device to operate reliably, even under ambient conditions. “Even the first nanopixels were stable for two weeks,” said Hecht, emphasizing the robustness of the design. The careful interplay of shape, materials, and current control makes this pixel viable for future integration into real-world devices.
Road to RGB Spectrum and Commercial Viability
Although the current design only emits orange light, the team plans to expand the color range to cover the full RGB spectrum. That would enable full-color displays suitable for AR and VR applications. The present efficiency sits at around one percent, a figure that Pflaum and his colleagues are aiming to improve in the next development phase.
The end goal is not just academic success but full usability in wearable optics. With pixels this small and efficient, smart displays could be integrated directly into eyeglass arms, projecting visuals onto lenses without bulky hardware. Future iterations might even allow contact lens integration, thanks to the scale and energy efficiency achieved.
This innovation doesn’t just push pixel density—it redefines where and how screens can exist.