Stanford and Samsung engineers have developed a new OLED display with purer colors and more than 10,000 pixels per inch (PPI).
The new OLED architecture is based on existing designs for electrodes of ultra-thin solar panels. According to the scientists, this kind of display could be especially useful for virtual and Augmented Reality (AR) technologies because the high pixel density results in more realistic and brighter images.
The brainchild of Stanford materials scientist Mark Brongersma, the new display – developed in collaboration with the Samsung Advanced Institute of Technology (SAIT) – actually stems from Brongersma’s research to create ultra-thin solar panel designs.
“We’ve taken advantage of the fact that, on the nanoscale, light can flow around objects like water,” explains Brongersma.
“The field of nanoscale photonics keeps bringing new surprises and now we’re starting to impact real technologies. Our designs worked really well for solar cells and now we have a chance to impact next generation displays.”
According to the scientists, the new ‘metaphotonic’ OLED displays not only have a record setting pixel density, they are also much easier and cheaper to produce.
OLED displays were on the mind of SAIT scientist Won-Jae Joo when he visited Stanford from 2016 to 2018.
During that time, Joo listened to a presentation by Stanford graduate student Majid Esfandyarpour about an ultrathin solar cell technology he was developing in Brongersma’s lab and realized it had applications beyond renewable energy.
Joo thereafter approached Esfandyarpour with his idea, which led to a collaboration between Stanford, SAIT, and Hanyang University in South Korea.
According to the scientists, the fundamental innovation behind both the solar panel and the new OLED is a base layer of reflective metal with nanoscale corrugations, called an optical metasurface.
The metasurface can manipulate the reflective properties of light and thereby allow the different colors to resonate in the pixels.
As pointed out by the scientists, these resonances are key to facilitating effective light extraction from the OLEDs.
Samsung is currently working on integrating this work into a full-size display with the same ultrahigh pixel density of 10,000 pixels-per-inch.
Image and content: Areous Ahmad-Pexels/Stanford University