Technology and applications have reached new heights, and flexible displays are emerging

We have been told for some time about the countless benefits that flexible displays promise, but actual flexible display devices have been slow to arrive. However, there are recent signs that flexible displays are poised to make a positive impact. What consumers see as the greatest value of flexible displays? Is it inherent durability? Ultra-thinness? Lightweight? Design freedom? Or a combination of other factors? Opinions are still mixed.

At this summer's Society for Information Display (SID) conference, two companies demonstrated a new flexible technology concept: e-skin, which is a flexible display covering all (or most) of the surface of electronic products. Kent Displays demonstrated a display with a large, irregularly shaped pixel on the front of a mobile phone. The cholesterol LCD pixel provides a medium for users to change the color of the phone to any of nine different colors. E Ink demonstrated a Hitachi mobile phone that uses a dot matrix electrophoretic display (EPD) electronic skin. The front of the phone can display 95 sets of pictures and graphics stored in the phone.

On the other hand, the development of flexible displays has also experienced ups and downs. On the positive side, Esquire magazine announced in July this year that the cover of its 75th anniversary edition will use an electronic cover developed using E Ink EPD flexible display technology; but on the negative side, Polymer Vision recently announced that the launch of its recently highly publicized "mobile book" - Readius e-reader has been delayed again and is expected to be launched in the second half of 2008. Moreover, the original concept of Readius was equipped with a 5-inch scroll-type E Ink display, which will now be replaced by a foldable display. According to the company, the reason for the change is that users are not confident in the reliability of the scroll-type display, despite the fact that it can withstand up to 15,000 pull-out/roll-in times. The display is an active matrix (AM) component using organic thin film transistors .

Prime View was the first company to introduce flexible AM ​​EPDs, demonstrating the technology for the first time in 2007. The display is a circuit transfer technology licensed from Philips that allows AM to be made on solid glass and then transferred to a flexible substrate. Prime View's first products include 1.9-, 6- and 9.7-inch display devices using E Ink technology.

Bridgestone, a company known for its tire manufacturing, also exhibited its flexible electronic paper displays developed using its self-developed electronic liquid powder (ELP) materials and quick response liquid powder display (QR-LPD) at SID 2008. These products, which are variations of EPD technology, include a 10-inch QR-LPD bendable display on a flexible glass substrate.

However, Bridgestone said it will begin manufacturing flexible QR-LPD displays using polyester film in late 2008. Bridgestone manager Takahiro Matsuse said the main appeal of flexible displays is "safety" -- they must be more resistant to damage and vandalism than rigid displays.

First active matrix electrophoretic display technology with circuits built on glass and then transferred to a plastic substrate

EPD technology is clearly a major player in the flexible display space. Not long ago, E Ink's manufacturing partners began using so-called front-plane multilayer bonding (FPL) technology, which combines a plastic substrate, a conductive coating, an EPD layer, and an adhesive layer for bonding to a second substrate (either flexible or rigid).