One of the most exciting developments in the display industry in the last fifteen years has been the discovery and development of polymer light emitting diodes (P-OLEDs).

The story started in the Cavendish Laboratory of Cambridge University in 1989, when it was found that 'organic' LEDs could be made using conjugated polymers. So began the history of Cambridge Display Technology (CDT).

In particular, polyphenylene vinylene (PPV) was found to emit yellow-green light when sandwiched between a pair of electrodes. The initial device efficiencies were very low, but researchers quickly realised the commercial potential of this discovery, especially for the manufacture of displays which emit their own light. These would offer significant advantages over the main display technology we still use today (liquid crystal display or LCD), in which a separate light source has to be filtered in several stages to produce the image we see.

P-OLEDs today

P-OLEDs have a number of intrinsic advantages over liquid crystal devices:

• P-OLED is an emissive technology: it emits light as a function of its electrical operation. 
• A P-OLED display consists of polymer material manufactured on a substrate of glass or plastic, and does not require additional elements such as backlights, and filters. 
• P-OLED technology is very energy efficient and lends itself to the creation of ultra-thin lighting displays that will operate at lower voltages.

The resulting benefits include brighter, clearer displays with viewing angles approaching 180 degrees, simpler construction offering the potential for cheaper, more robust display modules, and ultra-fast response times allowing full colour video pictures even at low temperature.  

 How do P-OLEDs work?

P-OLED Developments

Since the discovery of P-OLEDs in 1989, significant effort has been directed into the development of red, green and blue materials that exhibit high efficiency and stability under normal operating conditions, and to enable integration into flat panel display (FPD) applications.

Currently, most monochrome applications are within the reach of P-OLED technology, and standard display modules are commercially available.

Full colour displays typically use groups of three adjacent pixels emitting red, green and blue light. Rapid progress has been made in improving the performance of colour polymers and the devices in which they operate, so that today, a steadily growing range of commercial colour display applications are feasible.

This progress is due in no small part to the formation of a joint venture between CDT and Sumitomo Chemical (Sumation^TM), with teams of scientists in Cambridge and Tokyo, who co-operate and share IP from the two companies and also have access to the patents of the lumation^TM business formerly owned by Dow Chemical.

Read more about Sumation in English.

Read more about Sumation in Japanese.

P-OLEDs can be used to provide light of almost any visible hue and beyond

In addition to the work of CDT and Sumitomo Chemical, many other companies and institutions around the world are working on P-OLED technology to improve its underlying performance and manufacturability. For more information, please click here to go to our links page.

You can also check out our latest announcements.