Researchers have created the smallest organic light-emitting diode (OLED) pixel ever demonstrated, a breakthrough that could dramatically reduce the size of future display technologies, tells Science Daily. Developed by physicists at Julius-Maximilians-Universität Würzburg in Germany, the new pixel measures just 300 × 300 nanometers while maintaining brightness comparable to conventional OLED pixels that are several micrometers wide.
OLED displays are widely used in smartphones, televisions, and wearable devices because each pixel emits its own light, eliminating the need for a backlight. This structure enables high contrast, vivid colors, and efficient energy use. However, shrinking OLED pixels to extremely small sizes has been difficult due to physical and electrical limitations. Traditional designs break down at the nanoscale because electrical currents concentrate at the edges of tiny structures, causing metal atoms to migrate and form filaments that short-circuit the device.
The Würzburg research team overcame this challenge by combining the OLED with a nano-scale optical antenna made of gold. The antenna allows electrical current to enter the organic light-emitting material while simultaneously amplifying and directing the emitted light. To prevent destructive current concentrations, the scientists added a carefully engineered insulating layer that blocks current at the edges while leaving a tiny central opening roughly 200 nanometers wide. This design ensures stable current flow and prevents short circuits.
Even the first prototype nanopixels operated reliably for two weeks under normal environmental conditions. Although their efficiency is currently around 1%, researchers aim to improve performance and expand the color range to include full RGB operation.
The implications for display technology are significant. Because each pixel is extremely small, a full high-definition display with a resolution of 1920 × 1080 could theoretically fit into an area of about one square millimeter. Such compact displays could be integrated directly into wearable devices like smart glasses or even contact lenses.
If efficiency and color performance continue to improve, this nanoscale OLED architecture could enable a new generation of ultra-compact displays that blend seamlessly into everyday objects while delivering high-quality visual output.