Printed Electronics – the Missing Fragments
CAMBRIDGE, UK—01/25/07—Nowadays, the term printed electronics is taken to include printed electrics and even thin film devices that are likely to be printed in due course. Anything less risks missing the big picture, the subject is moving on so rapidly.
Of the different components that are becoming printable, Organic Light Emitting Diodes (OLEDs) are very important. This is because they are set to replace many of today’s electronic displays with something more economical and with better performance. They will do the same with much of today’s lighting as well. In both cases, the change will be accelerated by the advent of cost-effective flexible displays because they will have lower purchase and installation costs and they will open up a vast number of new applications where light emitting surfaces have been impractical in the past. However, cost-effective, flexible OLEDs with suitably long life may not be in mass production for a decade despite hundreds of organisations developing them.
About 70% of the patents on printed electronics, in the broad definition, relate to OLEDs and that is out of proportion to their potential. For example, light emitting displays will probably always suffer from being more expensive, poorer in definition and more wasteful of power than the best non-emitting displays. By contrast, electrophoretic signage and e-books only need power when their images are changed. Electrochromic and thermochromic displays are inherently cheaper and they, and ac electroluminescent displays, are available in flexible form today. Printed flexible AC electroluminescent displays are even available in areas of hundreds of square meters. All displays can be improved and all have considerable unrealised market potential. There is therefore scope for many more companies to work on the other displays, because fewer than twenty companies are involved seriously today. For example, more effort in improving their colours and lifetime would be well justified.