Flexible display technology has been under development for a few decades as companies have long sought innovative ways to deliver larger screens with smaller form factors. Recent announcements from Samsung and LG are shining an increasingly bright spotlight on breakthroughs in the enabling technologies to realize high-resolution flexible displays.
At the Consumer Electronics Show (CES) in January, LG introduced the 65-inch LG Signature OLED TV R with a screen that rolls up or down. Slated for sale sometime this year, the TV’s screen quietly and quickly unfurls at the touch of a button and then just as discreetly rolls up when not in use.
Samsung made a buzz at CES with its Galaxy Fold. Sporting the world’s first 7.3-inch Infinity Flex Display, it collapses into a 4.6-inch, pocketable format when closed. A marvel of display innovation, Samsung recently delayed the official launch of the Galaxy Foldamid questions about screen durability. Regardless of when this bendable, foldable smartphone hits store shelves, early adopters will be clamoring for the first entrant of a mobile device providing the ultimate visual experience in what will become a crowded field in years to come.
Capitalizing on evolving applications for dynamic, flexible display technology requires advanced soft materials science& engineering, integrated product design, and manufacturing innovation
ADVANCEMENTS IN SOFT MATERIALS SCIENCE AND ENGINEERING
The ability to leverage increasingly thinner yet durable multi-materials structures has enabled product designers and engineers to pursue the promise of flexible, foldable displays. A decade ago, this led to the development of wireless devices with “rollable” screens that opened and closed like a scroll as the mechanical properties of the soft materials used allowed opening and closing a million times without degradation. Unfortunately, these displays never caught on due to cost and consumer adoption risk as people didn’t want to use two hands to read displays.
As display technology evolved, so have advancements in soft materials science. Displays are getting thinner and more resilient to mechanical deformation due to the development of tougher, viscoelastic materials and novel, multi-materials structures, so they can bend more readily without breaking.
The combination of flexible glass, polymers, metals and other soft materials opens the door to a diverse mix of applications
For example, there’s a growing need for “one-time flex” materials that enable components and modules with integrated displays to bend to fit into specific product housing. Consumer appliances, retail and hospitality point-of-sale products, and automotive dashboards with gentle, aesthetically pleasing curves are ideally suited for these flexible displays.
Equally important are materials that provide intrinsic mechanical flexibility, to enable the integration of displays in every surface that can be touched to deliver the ultimate interactivity experience. In the automotive sector, there are endless applications whereby drivers and passengers could take advantage of flexible, interactive screens to transmit and communicate all kinds of visual data and audio.
Last, but certainly not least, are soft materials that are conducive to large, foldable screens, like the LG TV. The opportunity to transport large, lightweight and high-resolution displays that fold discreetly into tubes is useful for any application where information is shared most efficiently using a large display format. In group settings, these displays can enhance teamwork and collaboration. When embedded with sensors, foldable displays resembling blueprints can help firefighters map emergency situations in real time to support fire-and-rescue efforts.
NEW LEVELS OF DESIGN FREEDOM
Ongoing advancements in flexible, foldable, soft, multi-materials-based structures are impacting every aspect of product lifecycles, from design and supply chain to manufacturing, assembly, and delivery. Product designers not only must be familiar with evolving materials but also their respective mechanical, electrical, optical and thermal properties. This requires an understanding of the implications on global supply chains while ensuring proper materials can be sourced at the right prices, in desired quantities, and shipped to appropriate manufacturing locations.
Product designers must take much more into account when designing foldable, flexible displays. On one hand, they have more freedom to solve different problems as flexible displays inherently provide greater user functionality. On the other hand, working with flexible display technology can be complicated, requiring special expertise to circumvent integration challenges and ensures seamless integration between display and device.
In some cases, flexible displays can be used as the housing for the device. This adds a new level of manufacturing complexity. Product designers then cannot rely on traditional manufacturing solutions, such as injection molding, to create the housing. Once the display is no longer just a display, it has to provide mechanical strength in addition to flexibility. It’s critical to understand the limitations of “display as the housing” applications, as they must be addressed prior to manufacturing, final product assembly and testing.
CONVERGENCE OF DESIGN, MATERIALS AND MANUFACTURING INNOVATION
As flexible display technology continues to evolve, product designers, soft materials scientists and engineers, supply chain experts and manufacturing engineers will team to transform the development and delivery of groundbreaking products. They’ll overcome obstacles by ensuring that high-quality, bendable materials also possess the high degrees of fracture toughness required to resist cracking or breaking. Additionally, optimal optical properties must be sought for the highest resolutions while ensuring high-strength of adhesion between each functional layer of the display.
From a manufacturing standpoint, precision alignment plays a pivotal role, which is why automation is critical. When assembling the functional layers of flexible displays, it’s crucial to understand the difficulties of transitioning from the handling of rigid materials to working with flexible, stretchable soft materials that can deform along millions of axial orientations. Automation requirements will increase to minimize manual handling and the use of advanced soft robotic arms to compensate for deformation without scratching or fracturing the glass will be critical for high production yields.
Manufacturers uniquely positioned to optimize the opportunities provided by flexible displays hail from a cross-section of industries, including aerospace, automotive, consumer products, medical devices and telecommunications. While these sectors have been among the first to use advanced soft materials for non-display products, the growing list of new product opportunities enabled by flexible displays is proof positive that when it comes to advanced display technology, the future is flexible and soft.