There are several approaches to producing OLED materials, each has their individual benefits and drawbacks. The Polar OLED technology using its proprietary CrystOLED material can be applied to almost any approach and provides additional benefits, or a complete alternative. Flexibility in design is our strength.
The small molecule OLED (sm-OLED) approach gives excellent pixel density, colour quality and lifetime although the cost of production is relatively high and only possible onto glass substrates. This is because the production process utilizes a high temperature vacuum deposition step that is energy intensive and not suitable for plastic substrates. Maximum OLED size is constraint by oven size.
The competing polymer OLED (p-OLED) system can be produced using ink-jet printing methods by solvent printing of the light emitting polymer. This gives a much cheaper route to manufacture but gives rise to problems with pixel density and layered systems. The lifetime of these devices is often not as good as the sm-OLED approach.
Polar OLED uses an altogether different approach. We use liquid crystal based polymer networks: CrystOLED. Liquid crystals are the ‘fourth state of matter’ and were originally developed at the University of Hull, the home of Polar OLED. By using these materials, we are able to print or cast using solvents, the light emitting or charge transport layer. By then exposing this to UV or other suitable radiation, the Polar OLED material is cross-linked forming an insoluble layer. By using lithographic techniques, sub-micron resolution patterning is possible. By forming the insoluble layer, additional layers can then be added using different colour materials or patterns as required. Fully RGB devices have been demonstrated already.
This technology allows for high quality displays on both plastic or glass substrates as in the p-OLED approach but without the high cost of manufacture associated with the sm-OLED system