Flexible Electronic Displays: The future of smartphone displays

The technology is moving at such a lightening speed that researchers are coming up with strange ideas every now and then.  See through touch screen displays, flexible e-book readers or interactive data glasses are some of the strange technologies that are almost like science fiction but soon will become a reality. When it comes to displays, researchers are working to make any possible surface to display an image on.

Researchers, all over the world, are working to improve the form factor and designs of smartphones with the new flexible displays.  Over the past few years, the top smartphones have converged onto the same form factor: a large touchscreen display on a rigid slab-like device. Now, with the flexible displays around the corner, old selection of flip phones, slider phones, and swivel phones has disappeared. This technology has helped the mobile phone manufacturing and custom electronicmanufacturing in India take a new turn to create new and innovative form factors. With this, we can expect new devices that will bridge the gap between a watch, a smartphone, and a tablet.

Before knowing that whether flexible displays can lead to a revolution in smartphone design, let us first understand the some basics about flexible displays.

Flexible displays:

OLEDs are solid states devices that are composed of thin films of organic molecules that create light with the application of electricity. In comparison to conventional LEDs, OLEDs can provide brighter, crisper displays on electronic devices and uses less power. In Flexible OLEDs, there is a use of plastic substrates that allow the display to bend and twist. In flexible OLEDs, there is just one sheet of substrate and therefore, they are paper thin and lightweight and perfectly suitable for mobile phones and wearable electronics. Currently, flexible displays are used to make curved phones and televisions because while the display may be flexible, the internal components are intact.

Flexible displays can be of two types based on either Reflectivity or emissivity.

• Reflective based-E-paper technology
• Emissive based- Flexible OLED technology

Both these displays can show images and text while being bent without distortion or blank spots. Both these technologies do not rely on the backlight. However, the e-paper technology is comfortable for eyes like real paper as it reflects light and it can hold static image and text indefinitely without using electricity. On the other hand, flexible OLEDs emit light when its each individual light-generating pixel generates light when an electric charge is applied.

History of flexible displays:

Surprisingly, flexible displays have been in development for almost 40 years now. In 1974, engineers at Xerox PARC developed first electronic paper displays to limit the waste of paper. This paper was designed to replace physical paper and could be bend and distorted just like normal paper. The original image stays on display regardless of whether it was kept flat.

The famous Amazon Kindle e-book reader uses electronic paper technology. It houses electronic paper display as well as hundreds of other components such as a battery, processor, Wi-Fi radio, etc. Although, the display is flexible, the device is rigid as the other components housed are not flexible. E-paper is not suitable for phones and tablets as they have a very low refresh rate, ghosting issues and are yet to be mass-produced in color.

Why are flexible displays better over their rigid counterparts?

It is believed that flexible displays will shape the future smartphone display technology because of the multiple advantages they offer. Firstly, they are highly durable, light in weight and have thin dimensions with unique software commands. As there is a use of plastic substrate and their ability to flex, the electronic devices using these displays are less likely to crack and thus users will be relieved from the hassle of getting their screens changed. As compared to their rigid counterparts, flexible devices are lighter and thinner. With its ability to deform, users can get an access to a set of commands in their devices user interface. For example, when the device is folded, it will go into sleep mode.

Different forms of flexible displays:

As the flexible displays are cheaper in manufacturing, display manufacturers are working on new ideas and technology of these displays. Currently, curved displays have hit the market in the form of curved televisions. However recent patent filings suggest that soon flexible displays will be in the market in the form of bendable, foldable and roll able devices. In order to accommodate the need for larger displays, foldable displays are likely to come first. Soon, there will be bendable displays so that it could be used on individual’s wrist. Finally, there will be roll able displays that may be used in televisions and eventually a tubular device with a retractable roll out display.

What still needs to work on flexible displays?

Before the truly flexible devices hit the market, there is a big challenge. While the display is flexible, the machine used behind the display is not flexible. Further, using plastic has some advantages, but it is not as good as glass when it comes to protecting the thin film transistor from moisture, oxygen or other outer particles. The gadget manufacturing company in India and around the world will have to work on the phone technology to make tough enough to handle the effects of daily flexing.  Device manufacturers will have to work on the phone batteries and circuit boards to manipulate them to flex. One has to find some cost-effective and workable alternatives before the actual flexible devices hit the market.

Flexible smartphones: The concept for future mobile phones

The advent of the YOUM and other similar technologies makes it evident that there are flexible high-resolution displays available for mobile phones and tablets. In January 2013, Samsung showcased prototypes of their YOUM displays at CES. Samsung released its Galaxy note edge in September 2013 that has curve edge, which shows information at the side of the display. In March 2015, another Galaxy S6 Edge was launched from Samsung with two curved edges.

Similarly, LG is also working on its flexible prototypes and announced the release of G Flex in January 2014. This was a curved phone. After that, there was G Flex 2 was released. In June 2015, LG released an 18- inch roll able display prototype at SID and is planning to make its 60-inch version by this year. Besides this, LG is also working on its 6^th generation flexible OLED production line in South Korea.

Apart from these two brands, Nokia also released its flexible smartphone prototype “ Nokia Morph Concept Device” which is able to morph into different form factors. It can be expanded into a tablet and can be folded up to give a wristwatch. This ability to morph between different shapes and sizes allows you to have a single device for your entire life.

So, with all these prototypes and efforts by different manufacturers, it is clear that future of flexible smartphones is quite near. The times are not far when we will be carrying a folded device within our pockets and using it whichever way we want.