Researchers from UCLA's Henry Samueli School of Engineering and Applied Science have successfully developed an organic light-emitting device (OLED) that can be stretched by up to 1,000 times. They believe that it may open more doors for various technologies such as stretchable smartphones and other electronic devices.
Qibing Pei, a UCLA professor of materials science and engineering and principal investigator on the research said, "Our new material is the building block for fully stretchable electronics for consumer devices. Along with the development of stretchable thin-film transistors, we believe that fully stretchable interactive OLED displays that are as thin as wallpaper will be achieved in the near future. And this will give creative electronics designers a new dimension to exploit," said Prof. Qibing Pei in a press release.
The researchers stretched the OLED a thousand times, extending it 30 percent past its original shape and size, while maintaining its efficiency. In another experiment, the researchers was able to stretch it up to 100 percent from its original form and can twisted in multiple directions and folded by 180 degrees.
The OLED material comprises a layer of an electro-luminescent polymer blend between a pair of new transparent elastic composite electrodes, which are composed of a group of silver nanowires inlaid into a rubbery polymer that allows the device to be utilized at room temperatures. All of these layers are completely flexible.
The new OLED material can also be engineered in a quite simple all-solution-based process.
Jiajie Liang, a postdoctoral scholar in Pei's Soft Materials Research Laboratory at UCLA said, "The lack of suitable elastic transparent electrodes is one of the major obstacles to the fabrication of stretchable display. Our new transparent, elastic composite electrode has high visual transparency, good surface electrical conductivity, high stretchability and high surface smoothness — all features essential to the fabrication of the stretchable OLED."
The researchers also showed that this ultra-flexible OLED, rather than containing just a solid block of light, could also multiple pixels. This could herald for electronic displays involving many thousands of pixels. They created this by gathering the silver nanowire–based electrodes into a cross-hatched pattern, with a single layer of columns and a single layer of rows.
This research was published online in the journal Nature Photonics. Watch a video demonstration of the stretchable OLED from UCLA engineers.
