It seems like there’s been a lot of discussion about flexible displays, graphene or not, over the years so the announcement of the first graphene-based flexible display might seem a little anticlimactic. That’s one of the problems with the technology and science communities. Sometimes there’s so much talk about an idea or concept that by the time it becomes reality people think it’s already been done and is not news.
So, kudos to the folks at the University of Cambridge who have been working on this development for a long time. From a Sept. 10, 2014 news release on EurekAlert,
The partnership between the two organisations combines the graphene expertise of the Cambridge Graphene Centre (CGC), with the transistor and display processing steps that Plastic Logic has already developed for flexible electronics. This prototype is a first example of how the partnership will accelerate the commercial development of graphene, and is a first step towards the wider implementation of graphene and graphene-like materials into flexible electronics.
The new prototype is an active matrix electrophoretic display, similar to the screens used in today’s e-readers, except it is made of flexible plastic instead of glass. In contrast to conventional displays, the pixel electronics, or backplane, of this display includes a solution-processed graphene electrode, which replaces the sputtered metal electrode layer within Plastic Logic’s conventional devices, bringing product and process benefits.
Graphene is more flexible than conventional ceramic alternatives like indium-tin oxide (ITO) and more transparent than metal films. The ultra-flexible graphene layer may enable a wide range of products, including foldable electronics. Graphene can also be processed from solution bringing inherent benefits of using more efficient printed and roll-to-roll manufacturing approaches.
The new 150 pixel per inch (150 ppi) backplane was made at low temperatures (less than 100°C) using Plastic Logic’s Organic Thin Film Transistor (OTFT) technology. The graphene electrode was deposited from solution and subsequently patterned with micron-scale features to complete the backplane.
For this prototype, the backplane was combined with an electrophoretic imaging film to create an ultra-low power and durable display. Future demonstrations may incorporate liquid crystal (LCD) and organic light emitting diodes (OLED) technology to achieve full colour and video functionality. Lightweight flexible active-matrix backplanes may also be used for sensors, with novel digital medical imaging and gesture recognition applications already in development.
“We are happy to see our collaboration with Plastic Logic resulting in the first graphene-based electrophoretic display exploiting graphene in its pixels’ electronics,” said Professor Andrea Ferrari, Director of the Cambridge Graphene Centre. “This is a significant step forward to enable fully wearable and flexible devices. This cements the Cambridge graphene-technology cluster and shows how an effective academic-industrial partnership is key to help move graphene from the lab to the factory floor.”
As an example of how long this development has been in the works, I have a Nov. 7, 2011 posting about a University of Cambridge stretchable, electronic skin produced by what was then the university’s Nokia Research Centre. That ‘skin’ was a big step forward to achieving a phone/device/flexible display (the Morph), wrappable around your wrist, first publicized in 2008 as I noted in a March 30, 2010 posting.
According to the news release, there should be some more news soon,
This joint effort between Plastic Logic and the CGC was also recently boosted by a grant from the UK Technology Strategy Board, within the ‘realising the graphene revolution’ initiative. This will target the realisation of an advanced, full colour, OELD based display within the next 12 months.
My colleague Dexter Johnson has offered some business-oriented insight into this development at Cambridge in his Sept. 9, 2014 posting on the Nanoclast blog on the IEEE (Institute of Electrical and Electronics Engineers) website (Note: Links have been removed),
In the UK’s concerted efforts to become a hub for graphene commercialization, one of the key partnerships between academic research and industry has been the one between the Cambridge Graphene Centre located at the University of Cambridge and a number of companies, including Nokia, Dyson, BaE systems, Philips and Plastic Logic. The last on this list, Plastic Logic, was spun out originally from the University of Cambridge in 2000. However, since its beginnings it has required a $200 million investment from RusNano to keep itself afloat back in 2011 for a time called Mountain View, California, home.
The post is well worth reading for anyone interested in the twists and turns of graphene commercialization in the UK.