Researchers set record for OLED microdisplay resolution

Scientists at Germany’s Fraunhofer Institute have created an OLED microdisplay with a 10,000 dpi resolution, the smallest ever pixel size for a display of this kind.

The researchers were able to develop the extremely small pixels on 300mm wafers – OLED microdisplays have so far been developed predominantly on 200mm wafers.

The project, funded by the Saxon State Ministry of Economics, Labor and Transport (SMWA), used components with a display diagonal of 0.18 inches and pixel sizes of only 2.5 micrometers.

The OLED microdisplay will be presented at this week’s Display Week event in Los Angeles.

The technology was developed by the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology (Fraunhofer FEP).

In recent years, Fraunhofer FEP has developed a wide range of microdisplays in full-color or monochrome, from ultra-low power versions to high-resolution variants for use in AR/VR applications.

The resolution of OLED microdisplays has been limited by the availability of 300 mm wafers, which are in short supply. In part due to technical reasons, such as the availability of suitable transistors for the corresponding control of the OLED.

But with consumer expectation for better picture quality increasing all the time Fraunhofer researchers decided to examine the scaling effects in smaller CMOS technologies alongside the use of 300 mm backplane processes.

Philipp Wartenberg, head of the department for IC and system design, said: "In so-called ‘small node technologies, there is always the challenge of realizing the voltages required for driving in complex photonic systems.

“Thanks to an interdisciplinary research team and a completely new type of display architecture, we have succeeded in doing this for the first time in this project, while at the same time realizing extremely small pixels with a size of just 2.5 µm.”