The University of Chicago researchers have developed a new OLED display that can be bent or stretched to more than twice its length while still emitting light.

Figure 1. Stretchable OLED Display. (Credit: Image courtesy of Wang Group)

Figure 1 shows A material developed by Asst. Prof. Sihong Wang and Prof. Juan de Pablo can stretch more than twice its original length without disrupting its ability to emit light and display a clear image. According to the University of Chicago, the material, described in a research paper published in Nature Materials, could be developed to create flexible displays for various applications, including wearable electronics, health sensors, and even foldable devices. [1]

“One of the most important components of nearly every consumer electronic we use today is a display, and we’ve combined knowledge from many different fields to create an entirely new display technology,” said Sihong Wang, assistant professor of molecular engineering, who led the research with Juan de Pablo, Liew Family Professor of Molecular Engineering. [2]

“This is the class of material you need to finally be able to develop truly flexible screens,” added de Pablo. “This work is really foundational and I expect it to allow many technologies that we haven’t even thought of yet.” [2]

Making flexible, light-up polymers

The displays on most high-end smartphones, as well as a growing number of televisions, use OLED (organic light-emitting diode) technology, which sandwiches small organic molecules between conductors. When an electrical current is switched on, the small molecules emit a bright light. The technology is more energy-efficient than older LED and LCD displays and is praised for its sharp pictures. However, the molecular building blocks of OLEDs have tight chemical bonds and stiff structures. [2]

“The materials currently used in these state-of-the-art OLED displays are very brittle; they don’t have any stretchability,” said Wang. “Our goal was to create something that maintained the electroluminescence of OLED but with stretchable polymers.” [2]

Wang and de Pablo knew what it takes to imbue stretchability into materials—long polymers with bendable molecular chains—and also knew what molecular structures were required for an organic material to emit light very efficiently. They set out to create new polymers that integrated both properties. [2]

“We have been able to develop atomic models of the new polymers of interest and, with these models, we simulated what happens to these molecules when you pull on them and try to bend them,” explained de Pablo. “Now that we understand these properties at a molecular level, we have a framework to engineer new materials where flexibility and luminescence are optimized.” [2]

This new type of OLED would appear to outperform Samsung’s wearable health-monitoring system, announced in 2021, which could stretch by as much as 30% without adversely affecting display or monitoring performance. The researchers say that their stretchable OLED device could have a wide range of applications in next-gen wearable electronics and health sensors. [3]

“This is the class of material you need to finally be able to develop truly flexible screens,” said de Pablo. “This work is really foundational and I expect it to allow many technologies that we haven’t even thought of yet.” [3]

The team plans to develop new versions of the display, integrating additional colors into the fluorescence and improving performance and efficiency. [3]

“The goal is to eventually get to the same level of performance that existing commercial technologies have,” Wang said. [3]

Source: University of Chicago

References:

1. https://indianexpress.com/article/technology/science/flexible-oled-stretchable-research-8568680/
2. https://scitechdaily.com/revolutionary-stretchable-oled-display-bends-and-expands-an-entirely-new-display-technology/
3. https://newatlas.com/electronics/stretchable-oled-wearable-electronics/

Cite this article:

Hana M (2023), New Stretchable OLED Display Technology, AnaTechmaz, pp.430