Since their initial discovery in the 1950s, use of organic light-emitting diodes (OLEDs) in digital displays has become commonplace, even so, they have struggled to live up to the hype. Here Duncan Clark, operations director of OLED innovator NextGen Nano, sheds some light on the future of OLEDs and how they are making an impact in the automotive industry.
In 1987, chemists at the Eastman Kodak Company, known today simply as Kodak, developed the first practical OLED device. It was developed using a two-layer structure sandwiched between an indium tin oxide anode and an alloyed magnesium:silver cathode with light emission occurring in the middle of the organic layer. Little did we know that OLEDS would still be such a hot topic today, over 33 years later.
Putting OLEDs to use
Unlike traditional LEDs, the emissive electroluminescent layer of OLEDs is a film of organic compounds that emit light in response to an electric current. However, like with their traditional counterparts, the semiconductor material of OLEDs can be doped, fine tuning them for a variety of applications.
What’s more, because the organic layers of an OLED are thinner and lighter than the crystalline layer of LEDs, the conductive and emissive layers of OLEDs can be multi-layered. This is extremely beneficial in the automotive industry where lightweight materials are highly sought after.
For example, German car manufacturer Audi now offers high-end OLED-based optional extras on its latest vehicles. The new Q5 luxury SUV offers customers looking for the technological edge the chance to take advantage of special OLED tail lights called signatures.
“The tail lights turn into a kind of display on the outer shell, which will provide us with ample opportunities and prospects in terms of design, personalisation, communication and safety”, explained Thomas Werner, OLED technology project manager at Audi.
The OLED tail lights aren’t purely a cosmetic feature, they also enhance safety. They are connected to sensors at the rear of the vehicle that will detect oncoming vehicles and shine at full brightness if they get too close.
The future of OLEDs
It is evident that OLEDs offer key benefits compared with traditional LEDs, something manufacturers are increasingly trying to take advantage of. Firstly, because they produce their own light rather than relying on a backlight, they have much larger fields of view than their traditional counterparts. Furthermore, unlike LEDs, they can create a state of true black when not emitting light. This creates higher contrast displays and increased efficiency since no power is used unnecessarily.
Researchers are not stopping there though, research is ongoing, continuing to push the boundaries of what is possible with OLED technology. For example, in a recent paper published in Nature Communications, Dr Franky So, chief technology officer at NextGen Nano, explored new blue OLEDs with a power efficiency close to existing blue phosphorescent OLEDs, particularly at high brightness. This research could facilitate the creation of devices with superior levels of luminosity, which use half the energy of current systems.
OLED technology has come a long way in 33 years, from a novel idea to being commonplace in our everyday lives. As researchers like Nextgen Nano and manufacturers like Audi continue to push the boundaries, who knows what the next 33 years might bring. To keep up to date with NextGen Nano’s research into OLEDs, click here.