OLED displays are gradually replacing LCD displays in the mobile devices we use every day. And it is no wonder: OLED displays are energy efficient and offer excellent image quality. These displays do, however, have a major drawback. They require the use of anti-glare filters that also drastically reduce the amount of light emitted by the diodes. This has a negative impact on yields. A recent innovation could change all that!
To do their job of preventing outside light from reflecting on the panel's metal lines, today's filters only let circularly polarized light through. However, this kind of light accounts for only half of the total light emitted by the diodes. The researchers decided to modify the system so that more of the light would be circularly polarized, limiting losses due to the anti-glare filter.
CNRS scientists in Rennes and scientists from the CEA Saclay campus developed a molecule that emits mainly unidirectionally polarized light. CEA-Leti scientists then developed the ideal optical system for this modified OLED, using stacked organelles, mirrors, and absorbers to obtain maximum performance.
The innovation has only been tested on a single large (5x9 mm²) pixel so far. But it does provide a sneak peek at what the next big advance in display technology could look like. The modified-OLED technology could also be of interest for the healthcare (lensless imaging) and entertainment (3D movies) industries.