The University of Michigan has announced a study that could lead to a breakthrough in OLED technology.
The discovery, per a university press release, has the chance to free up 20 percent more light from OLEDs. The new technology, the university said, “could help extend the battery life of smartphones and laptops, or make next-gen televisions and displays much more energy efficient.”
The new approach, per the announcement, “prevents light from being trapped in the light-emitting part of an OLED, enabling OLEDs to maintain brightness while using less power. In addition, the electrode is easy to fit into existing processes for making OLED displays and light fixtures.”
The study was published in the journal Science Advances, under the title “Tackling Light Trapping in Organic Light-Emitting Diodes by Complete Elimination of Waveguide Modes.”
Conventional waveguide mode decoupling methods for organic light-emitting diodes (OLEDs) are typically not scalable and increase fabrication complexity/cost. Indium-tin-oxide–free transparent anode technologies showed efficiency improvement without affecting other device properties,” the study’s abstract said. “However, previous works lack rigorous analysis to understand the efficiency improvement. Here, we introduced an ultrathin silver (Ag) film as transparent electrode and conducted systematic modal analysis of OLEDs and report that waveguide mode can be completely eliminated by designing an OLED structure that is below the cutoff thickness of waveguide modes.
“With our approach, you can do it all in the same vacuum chamber,” L. Jay Guo, U-M professor of electrical and computer engineering, said of the study. “Untreated, it is the strongest waveguiding layer in the OLED. We want to address the root cause of the problem.”
“Industry may be able to liberate more than 40% of the light, in part by trading the conventional indium tin oxide electrodes for our nanoscale layer of transparent silver,” Changyeong Jeong, another author of the study, said. “Some researchers were able to free up about 34% of the light by using unconventional materials with special emission directions or patterning structures.”
How soon will this new technology be used in actual OLED products? That remains unclear, as there are many steps remaining before the research has applications for TVs, phones, and other hardware that uses OLED technology.
Of RTINGS’ current rankings of the best available TVs, the top rankings are dominated by OLED TVs. The entire top ten of the current list is entirely taken up by OLED models, from Sony, LG and Vizio, while the highest-ranking non-OLED TV on the list is Samsung’s QN90A QLED model, which is 11th. Another Samsung model, the Q90/Q90T QLED TV model from 2020, is ranked thirteenth.
Stephen Silver, a technology writer for The National Interest, is a journalist, essayist and film critic, who is also a contributor to The Philadelphia Inquirer, Philly Voice, Philadelphia Weekly, the Jewish Telegraphic Agency, Living Life Fearless, Backstage magazine, Broad Street Review and Splice Today. The co-founder of the Philadelphia Film Critics Circle, Stephen lives in suburban Philadelphia with his wife and two sons. Follow him on Twitter at @StephenSilver.