Latest Developments in Flexible Displays

Written October 16, 2019

For some time now, I’ve believed that before we see commercially viable flexible displays that we’ll need to see other flexible devices.  While there are lots of great efforts underway to develop flexible displays, there are two reasons that other devices will see commercialization before displays: Displays are at the top of the food chain when it comes to the technologies necessary to achieve flexibility.  In other words, displays are difficult to make — and the fact that the primary performance characteristic of a display is visual — the judgment criteria by which we judge success, is made even more difficult due to the flexibility.

Before we can incorporate flexible displays into commercial devices, there is also a need for other technologies to be flexible.  It’s not compelling to have a flexible display, if it must be attached to a brick that houses other key components (storage, memory, batteries, sensors, CPU, connectors, etc.).  For these reasons, the industry hype has shifted a bit from being focused on flexible displays, and instead is focused more generally on flexible electronics.

KAIST Researchers Develop Bendable Lithium-ion Battery

Researchers at the Korea Advanced Institute of Science and Technology (KAIST) have developed a promising solid state, thin-film lithium-ion battery that claims the highest energy density ever achieved for a flexible battery. The new design, which showed for the first time that high-performance thin films can be used for flexible batteries, may be commercialized as early as next year.

The new approach developed at KAIST uses high energy density inorganic thin films that can be treated at high temperatures, resulting in the highest-performance flexible lithium-ion batteries yet. The batteries are built by sequentially depositing several layers — a current collector, a cathode, an electrolyte, an anode, and a protective layer — on a brittle substrate made of mica.

Then, the mica is manually delaminated using adhesive tape, and the battery is enclosed between two polymer sheets to improve mechanical resistance. Bending the battery affects performance, but not to disastrous levels. With the battery constantly bent at a radius of sixteen millimeters (about the same curvature of a fifty-cent coin) the discharge capacity drops by about seven percent after 100 charge-discharge cycles, compared to a three percent drop when not bent.

See-through and flexible 3-D memory chips developed at Rice University

A revolutionary change is to go off in memory chip design, capability and power-efficiency. James M. Tour, PhD, a scientist at Rice University, has designed a new translucent and flexible memory chip with a unique 3-D internal architecture. The new memory chips that can withstand 1,000-degree Fahrenheit temperature and other rough conditions will increase the efficiency and performance of cell phones, tablets and other handheld devices. Silicon oxide is the active component in the new memory chips.

Intrinsiq Materials leads €1.3M program to develop copper inks for medical device applications

Intrinsiq Materials is leading a consortium to develop its novel nanoparticle copper ink technology for use in medical devices under the UK Government funded PROCID program. The PROCID program will run to the end of 2013 and is designed to prove the cost-effective use of printed copper in low-cost antibody based biosensors for disease detection, initially targeting chlamydia and gonorrhea. The consortium consists of Leeds University, ELISHA Systems Ltd,

The Ryedale Group, The Needham Group, Amies Innovations, and P1 Technology, with Intrinsiq Materials leading the program and providing their novel copper ink technology. Intrinsiq’s copper inkjet ink, “Intrinsiq CI,” and copper screen print paste, “Intrinsiq CP,” are innovative ink formulations designed for photonic curing at room temperature in air, by laser or broad band flash techniques. Conductivities are comparable to commercial silver inks on a range of substrates, including PET and paper. The company has additional inks under development, including nanoparticle based nickel and silicon.

Princeton University Puts Wrinkles into Solar Panels

New flexible, low-cost solar cells, inspired by the microscopic folds found on the surface of a leaf, offer a 47 percent increase in electricity generation. Engineers at Princeton University got the idea by observing basic leaf structure, which is designed to bend and control sunlight for maximum production of energy and nutrients.

They simulated these qualities on the surface of a photovoltaic material, adding finely calibrated folds to channel the lightwaves and to increase the material’s exposure to light. Current solar panels are made of costly and fragile silicon. So far, plastic panels have not been practical for widespread use because their energy production has been too low. However, scientists have been working to increase that efficiency with the goal of creating a cheap, flexible and tough source of solar power.

If a plastic panel’s efficiency can be increased, the material could produce power from an array of surfaces – from inserts in window panels to overlays on exterior walls or backpacks. The team created the folded surface by curing a photographic adhesive layer with ultraviolet light. By controlling how fast different sections of the adhesive cured, the team introduced stresses in the material and generated ripples on the surface.

The shallow ripples are called wrinkles, and the deeper ones are called folds. The researchers observed that a combination of folds and wrinkles produced the best results. The researchers discovered that panels with folded surfaces retain their effectiveness after bending, whereas a standard plastic panel’s energy production diminishes by 70 percent after being bent. The team is hopeful that this new insight can be applied to synthetic devices. The research appeared online on April 22, in Nature Photonics. In so many areas, we are seeing remarkable developments, using novel materials, of flexible electronic devices. These developments of relatively simple devices will be the building blocks upon which the ultimate development of high-performance displays, which are coming more quickly than most analysts are currently projecting.