For Flexible Displays, We don’t need your stinkin’ OLEDs!

At the last SID Display Week, Merck and FlexEnable were enthusiastically promoting their cooperation in developing flexible LCDs, and in late July FlexEnable and Chinese LCD maker Truly announced the signing of a technology transfer and licensing agreement.

“The deal aims to bring FlexEnable’s flexible organic liquid crystal display (OLCD) technology into mass production on Truly’s lines within 2018,” said a FlexEnable press release issued on July 31. (Truly and FlexEnable Sign License Agreement to Bring Low-cost, Scalable Flexible Display Production to China)

FlexEnable uses the technology and much of the personnel formerly associated with the early organic TFT (OTFT) developer, Plastic Logic. The company uses its low-temperature OTFT backplane technology to fabricate flexible backplanes low-cost plastic substrates such as TAC and PET. FlexEnable says it can deliver “flexible displays with large area, low cost and high brightness with long lifetime,” and with a bend radius 20 mm or less. Thats 0.8 inches, not pOLED territory but plenty good enough for many applications. FlexEnable claims “the OTFT backplane has better electrical performance than amorphous silicon, giving plastic LCDs the same display quality and reliability as glass-based LCDs.”

Flexenable flexible LCD with organic TFT backplane. Photo FlexenableFlexenable flexible LCD with organic TFT backplane. Photo Flexenable

Truly, a major Chinese LCD manufacturer, will implement the process into its existing production lines in Shanwei, China. The first product samples will be available to commercial partners in early 2018, with volume production expected in late 2018. KK Ho, General Manager of Truly’s R&D Center, said ”FlexEnable’s OLCD technology is a breakthrough in the TFT-LCD industry and with its characteristics of thinness, lightweight, and more durability it is going to create lots of possibilities for innovative product design. We have been receiving many enquiries for flexible display from the market, specifically, wearable devices, smart home appliances, electric cars, and self-driving cars, etc. This is a pretty exciting display technology and we do believe there is a considerable potential market size.”

But wait a minute. Even if FlexEnable’s organic backplane is as good as the company says it is, it’s just a backplane. Where’s the flexible LCD? We’re talking about a radius of curvature much, much smaller (and much more meaningful) than the slight curvature in curved LCD TV sets. If you curve an LCD more than slightly, you compromise the precise alignment between the layers and the precisely determined gap between the layers that is required for consistent characteristics and good image quality.

Merck Enters the Scene

That’s where Merck comes in. As first reported in Display Daily more than two years ago, Merck developed an LCD material containing a photopolymer and a practical process that produces an LCD “sandwich” with polymer substrates and polymer walls that stabilize the LC gap even with the display is bent. As anounced shortly after Display Week, FlexEnable and Merck are collaborating to make flexible LCDs that combine FlexEnable’s flexible backplanes and Merck’s polymer wall technology.

So, we can assume that this is the combination of technologies that Truly will be sampling early next year. For such a radical new LCD architecture, the polymer-wall front-plane technology has been developed very quickly. (FlexEnable, and Plastic Logic before it, has been sweating the organic backplane for a much longer time.) If Truly acquires large customers for the new product and achieves volume production by late 2018 as promised, it will be a very impressive achievement. – Ken Werner

Ken Werner is Principal of Nutmeg Consultants, specializing in the display industry, manufacturing, technology, and applications, including mobile devices and television. He consults for attorneys, investment analysts, and companies re-positioning themselves within the display industry or using displays in their products. He is the 2017 recipient of the Society for Information Display’s Lewis and Beatrice Winner Award. You can reach him at [email protected].