Bending

words: Dan Rogers

24 Bending the rules

Corning is developing its glass for use as layers for flexible displays Photo: Corning

Flexible displays are on their way

25 hen Samsung to introduce sometime in announced plans 2012, hopefully the earlier part. W to introduce The application probably will flexible OLED displays in 2012, start from the handset side.’ there was much excitement – and a little confusion – about Yi also suggested that what the first applications of flexible displays would be these screens would entail. developed for use in tablets and other mobile devices. The conclusions made in certain quarters of the media Flexible? that Samsung was announcing ‘Flexible’ is a term that covers plans to introduce bendable a wide array of innovations phones in the near-term – in the field of displays – from

UK tabloid newspaper the conformable displays that can Images 2a and 2b: Samsung Daily Mail announced ‘Your be bent occasionally during is among the firms to have demonstrated flexible flexible friend? Samsung the design process for what displays at previous to release bendy-screened is ultimately a rigid device; industry events, such as the 2011 Consumer Electronics phones “in Spring 2012”’ – displays produced on flexible Show appear to be a little hasty. substrates that can be added to Photo: OLED-Display.net a rigid device without the need Nevertheless Samsung’s plans for glass; to screens that can be to exploit more flexible OLED folded or even rolled without ... flexible displays in 2012 indicate that compromising performance. the consumer electronics displays have market is gradually moving Following the market become one in the direction of realising success of OLED displays in advanced concepts like – with tablets of the most bendable and rollable screens. and televisions among the next exciting targets for Samsung and LG – PC World reported that flexible displays have become areas of Samsung spokesman Robert one of the most exciting areas commercial Yi stated during an earnings of commercial development for call in September 2011: ‘The the plastic electronics industry. development flexible display, we are looking for the plastic The 2012 Flexible Electronics & Displays Conference & electronics The flexible Exhibition taking place on 6-9 industry. February in Phoenix, Arizona, display, we the US, will be one to watch, a chance to look in detail at are looking with so much activity expected what can be achieved in the in this space. Following the near-term with the technology. to introduce likely unveiling of flexible sometime display technology at the 2012 Having led the production Consumer Electronics Show and implementation of OLED in 2012, (CES) in January, the FlexTech displays in smartphones – now hopefully the Alliance event will give the one of the primary hardware earlier part. plastic electronics industry features that distinguish

26 www.plusplasticelectronics.com Flexible definitions What is a ‘flexible’ display? – a with a curved OLED display – demonstrated There seem to be some clear categories of device defined to varying that it was taking steps into degrees as flexible: conformable displays too. Conformable Maturity A display that can be flexed or curved slightly during the So the South Korean manufacturing process, before being set into a rigid device. company’s latest announcement suggests that The Galaxy Nexus smartphone boasts a curved OLED display, the various elements required encased in glass. to create a reliable flexible Glass-free display – high-performing materials and layers, A flexible display that can be flexed during the manufacturing process robust device structures, and also uses glass-free encapsulation. and scalable production processes – are reaching the These displays are thinner and lighter than rigid displays level of maturity needed to encased in glass. The removal of glass also makes the device make the step to the next less susceptible to breakages. generation of OLED displays. Flexible A display that can be flexed or bent many times during use, without affecting the display’s output. ... the South Some e-paper displays are able to perform consistently despite Korean repeated flexing, but consistent, high-performing OLEDs have company’s not been publicly announced. latest These devices would allow users to use and carry devices in new announce- ways – for instance, wrapped around a wrist. ment Rollable and foldable A display designed specifically to sustain folding and rolling, often suggests that making them more portable. the various

Rolling a display requires devices to frequently undergo tight elements bend radii as they are retracted into a case or similar display required holder, then rolled out for use. to create Netherlands-based Polymer Vision has demonstrated rollable a reliable e-paper displays that can withstand hundreds of thousands of rolls without declines in performance, but OLEDs remain a long- flexible term challenge. display ... are reaching a premium mobile device offers valuable unique selling – Samsung has reaped the points. Earlier in 2011 the the level of rewards of introducing new company’s collaboration with maturity display technology that Google on the Galaxy Nexus needed ...

VOLUME 4>ISSUE 4 27 that can be rolled and put in a York-headquartered Corning ... a lot of pocket get media coverage for believes it has a solution that progress has flexible displays developments, can reliably protect a flexible it is these rather more OLED display – based on glass. been made practical advantages that with barrier will drive flexible displays to The glass company, which market in the near-term. produces the Gorilla Glass layers for material used widely for OLEDs, And it is possible these like-for- consumer electronics displays, like replacements of glass- has created OLED layers like which could encased displays for robust, touch panels, colour filters and allow you to glass-free, lighter flexible backplanes for flexible displays. OLEDs are what Samsung is get rid of a aiming to introduce in 2012. Its colour filter technology, glass layer. demonstrated at high Glass-free efficiency and throughput in a The move to flexible displays One challenge that could roll-to-roll process, uses a thin makes good sense. OLEDs inhibit the move to flexible and flexible glass material. are praised for the quality displays is the barrier of the display’s resolution layers required to replace The company will and its wide viewing angle glass encapsulation. While demonstrate the process for among other features that Feenstra notes progress made glass-based flexible layers help differentiate an OLED- in this area, glass remains at the CES and FlexTech based smartphone from an the reliable material in conferences in Q1 2012. LCD counterpart; but the commercial use for displays. characteristics of a flexible ‘Working with glass OLED display would help Yet the move to flexible spooling may seem a bit distinguish a device in the displays may not mean counterintuitive, because market even more markedly. abandoning glass for polymer- people tend to think of glass as based encapsulation. Contrary being rigid and brittle. We’ve ‘The biggest advantage for to conventional wisdom, New made glass material that is thin flexible displays is that you can enough and conveyed flexible avoid glass breakages, as well as glass on a roll-to-roll process, the lighter weight,’ states Johan then rolled the material back,’ Feenstra, CEO at the Samsung explains Dipak Chowdhury, LCD Netherland R&D Centre.

‘A lot of products end up We’ve made going back to the maker glass material because of glass breakages. And a lot of progress has been that is thin made with barrier layers for enough and OLEDs, which could allow you to get rid of a glass layer.’ conveyed flexible glass While concepts like Corning glass being wraparound, wrist-worn produced in a roll-to-roll on a roll-to- process smartphones and displays Photo: Corning roll process ...

28 www.plusplasticelectronics.com Ten-year Forecast of Disruptive Technologies in Lighting and Displays to 2021

WHAT DO YOU GET? 0 The disruptive technologies that will have the greatest impact on the lighting and displays industries 0 Realistic how-and-when scenarios that look at the probability of success and impact of the top-25 disruptive technologies 0 Key end-use and technology trends in lighting and displays

REPORT SUMMARY This major new report identifi es and profi les the disruptive technologies that are most expected to aff ect the lighting and displays industries over the next 10 years to 2021. Ten- year Forecast of Disruptive Technologies in Lighting and Displays to 2021 is the essential planning and strategy guide. It provides exclusive data and analysis, detailing how current and emerging trends will shape the future of the industry, along with realistic scenarios for how and when the disruptive technologies are likely to be fully integrated into the lighting and displays supply chains. This report is a must-read for anyone working in the lighting and displays sectors.

FOR FURTHER INFORMATION CONTACT Price: £3,250, €3,650, $5,260^ Bill Allen email [email protected] call +44 (0)1372 802086 IntertechPira members web www.intertechpira.com/marketreports receive a 10% discount

^Please note that advertised € and $ prices are indicative and subject to exchange rate fl uctuations. Flexible display developments While efforts to commercialise various forms of flexible displays are ongoing, some compelling proofs-of-concept have been presented by the plastic electronics industry.

Flexible rewritable e-paper The Taiwan Industrial Technology Research Institute (ITRI) has demonstrated flexible e-paper that can be printed and rewritten around 250–300 times. The i2R paper is printed using a thermal printing head, a technology found in many standard fax machines.T he e-paper intended to replace the need to print multiple documents, such as in office use, or could be used to event tickets, point-of-sale displays and other printed media.

Dipak Chowdhury, programme director for PaperPhone flexible glass, Corning Photo: Corning The PaperPhone concept consists of a 9.5cm flexible e-paper screen that responds to bending and stylus input. The device was created at Queen’s University, Canada and unveiled in May 2011. programme director for flexible displays at Corning. The ITRI has also demonstrated flexible displays for consumer electronics devices. One is the FlexUPD, a 6-inch OLED screen ‘We’ve produced the material that the organisation claims offers good water vapour barrier at dimensions such that properties. The technology was unveiled in December 2011 the width of the printed alongside a flexible touch panel. area could go to gen. five.

‘We’re working with partners and enabling them to use readiness to deliver flexible Fully flexible displays our glass. Our target is that OLEDs in 2012, progress by that can sustain repeated by the second half of 2012, the likes of Corning suggests bending, folding or rolling supply chain implementation that wider use of conformable appear to be far from will have been executed.’ and possibly glass-free OLEDs realisation, despite progress could happen in the near-term. on backplanes and other Flexible future But what of fully flexible, parts of the device. Chowdhury argues that bendable, or rollable displays? companies looking to Alongside OLED displays, introduce flexible displays The fortunes of Polymer there is also the market will need to use glass if they Vision, the Netherlands- for flexible e-paper are to achieve commercially based developer of rollable displays to consider. viable standards. display technology, indicate that this is a long-term effort E-paper, which has reached ‘With OLED the challenge, that will require substantial a greater stage of maturity other than the backplane, investment in the coming as a flexible display medium is encapsulation – years to be realised. The than OLED, could provide particularly the flexible company was recently divested flexible backplanes with ones,’ he comments. by its Taiwanese owner the opportunity to prove Wistron and is now looking that they can be bent and While it is difficult to establish for strategic investors (see rolled repeatedly without the extent of Samsung’s Looks good on paper, p.4). losses in performance.

30 www.plusplasticelectronics.com If someone can truly find a need for a rollable display then we can make it. The technology is there.

mass-production, according to ’s chief marketing The Plastic Logic 100 uses a flexible backplane technology for its e-reader display officer Sri Peruvemba. Photo: IntertechPira Although the device is The Plastic Logic 100 e-reader complement its flexible E Ink framed in rigid plastic, the for the education markets, display. The device has been combination of flexible boasts a flexible organic trialled in schools in a number backplane and e-paper semiconductor backplane to of countries and is now in is likely to be seen more frequently in the near future.

Design need Useful links However Peruvemba feels + 2012 Flexible Electronics & Displays Conference & Exhibition the benefits of a rollable or – www.flexconference.org foldable display need to be defined first – and suggests + auo develops solar-powered flexible e-reader – bit.ly/u4Ppfg that it is the design need, not the technology, that is + european project develops rollable displays – bit.ly/tfWljM holding flexible e-paper back.

+ flexible phone brings concept closer to reality – bit.ly/ve1Gbz ‘If someone can truly find a need for a rollable + google, Samsung unveil smartphone Galaxy Nexus display then we can – bit.ly/nkQDqI make it. The technology is there,’ he remarks. + plastic Logic e-reader to go into Russian schools – bit.ly/u3wZoi ‘The scroll disappeared for a reason: it’s not practical + samsung Electronics to launch flexible OLED-based products as you have to roll it out in 2012, probably start with phones – bit.ly/v5IRmx every time you want to look at it. The same practical + truly flexible displays are not yet ready for market problems apply to plastic – bit.ly/spPGu7 versions. People want a notepad, not a scroll.’ + wistron to divest flexible displays firm Polymer Vision – bit.ly/vkGzMb VOLUME 4>ISSUE 4 31 The controllers, and systems layers suggest – the move to enable animation and to flexible substrates and advantages video-rate displays. Other lower-temperature processing of flexibility development work is focusing could deliver significant on colour e-paper displays, production cost savings for are really using flexible colour filters. display manufacturers. felt in bigger Practical uses ‘It’s fair to say we’re seeing displays. The However it is likely that more interest in solution iPad is quite monochrome e-paper will processing,’ says Michele help determine the appeal of Ricks, business development heavy, for more flexible displays, which manager for OLED instance. in turn will validate efforts to materials at Merck. develop more flexible – or even foldable or rollable – OLED ‘The industry as a whole Peruvemba suggests that displays in the long-term. has more confidence that flexible backplanes could it is viable, where previously unlock other beneficial uses Aside from the appeal inherent there was skepticism that of flexible displays though. in a flexible display-based it would never be able to device itself – the lighter compete [with vapour ‘In other applications there weight, the ruggedness deposition]. The question are possibilities, for displays offered by eschewing glass, now is “What will be that tend to be smaller – for the thinness that can be the right method?”’ instance, a wraparound mobile achieved – there are potential phone, or military use displays benefits for processing on IMPACT where there is definitely cheap, flexible substrates. If Samsung introduces new a need for a much more products in the smartphone conformable device,’ he adds. While some organic market in 2012 using glass- technologies are relatively free flexible displays, it could E Ink is working with immature – as Corning’s prove to be as significant partners on new drivers, comments on flexible glass a change as the original implementation of OLEDs – possibly even more so.

And the benefits of a flexible display have the potential to make an even greater impact in other, lucrative product categories in the coming years too.

‘The advantages of flexibility are really felt in bigger displays. The iPad is quite heavy, for instance: it would be a benefit to customers to Flexible OLED displays could signal the end of the use of have a lighter display in a rigid sheets of glass to encapsulate a screen Photo: OLED-Display.net tablet,’ Feenstra notes. +

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