In Oct, 2013, Samsung Display mass produced a display using the world’s first flexible AMOLED (active matrix organic light-emitting diode) technology in a curved design, and applied it to the Samsung Galaxy Round smartphone. Last year, with the release of the Galaxy Note® Edge, it improved the technology as the YOUM Bended Display and saw it introduced in the Samsung Note Edge display. With its new Flexible AMOLED Display, Samsung Display is now taking a major step to advance design innovation in the smartphone market even further with its first dual-edge display being introduced in the Galaxy S®6 edge, which features two nicely curved or beveled sides.
Flexible AMOLED technology will continue to evolve from curved, to bended, foldable and even “rollable” designs. Our ‘Edge’ displays are actually the vanguard of the second phase – bended displays.
Samsung Display’s Flexible AMOLED uses polyimide (PI), an advanced type of plastic, as the substrate material rather than hard glass used in rigid AMOLED panels. PI is a high polymer material with characteristics of exceptional flexibility, resilience and shock resistance. Samsung has been able to make an extremely thin film out of it – less than a millimeter thick (thinner than a human hair). That’s thinner than any other display on the market today. With the thickness of the AMOLED substrate being less than half the thickness of glass substrates in conventional mobile LCD displays, Samsung has been able to deposit an electronic circuit onto it and evaporate a luminant RGB organic device, to realize the display’s industry-leading bendable characteristic – making it potentially more bendable than a human hair.
Degree of Curvature
Our new Flexible AMOLED display can be used in a ‘dual-faceted’ design with two rounded sides or in single-edge applications. Thanks to a curvature of 6.5R for each side, the consumer-minded design is easy to grab onto with just one hand. ‘UX Matters’, an American non-profit organization analyzing user experiences with mobile devices, recently confirmed that, indeed, most people use only one hand to search for information on their mobile device. In particular, most use their right thumbs to swipe their screen for touch commands.
Samsung’s Flexible AMOLED delivers Quad HD picture clarity at 1440 X 2560 pixels with a pixel density of 577 ppi, currently the highest resolution available for any smartphone. It can deposit more than 3.6 million RGB organic subpixels on its PI substrate, allowing the user to see the finest image detail and the smoothest fonts. The total number of pixels in the Flexible AMOLED display is 75 percent higher than the number in a full HD AMOLED screen like that used in the Galaxy S®5.
The Flexible AMOLED Display can drive each of its pixels individually. This helps it to reduce power consumption. Its pixel control allows for the use of ‘partial operation technology’ permitting a smartphone to make use of only 7mm of each column of the curved display at any one time — therein reducing power consumption today by about 20 percent and possibly more in the future. Comparatively, note that in an LCD mobile display, a simple widget or pop-up message uses the entire backlight unit to illuminate the screen.
The Flexible AMOLED has the industry’s highest color reproduction rate. It has a color gamut that perfectly supports the Adobe RGB color scale. Adobe RGB covers a 30% wider range of colors than sRGB, which is the most frequently used color standard today. QHD AMOLED display technology can depict almost 100% of Adobe RGB, while LCD can replicate only about 70% because of its inherent structural limitations in requiring a backlight illumination source.
Speeds and Image Clarity
Due to the display’s highly advanced ability to rapidly adjust brightness levels, consumers won’t be bothered by image artifacts while watching a movie, video clip or game, nor be subjected to annoying eyestrain when watching for long hours. AMOLED can respond to image transitions quickly because of light-emitting subpixels that produce their own color. On the other hand, an LCD display passes light by changing the orientation of its liquid crystals (LC). So when the LC’s response speed slows – for example at low temperatures, transition time slows down, too. The Flexible AMOLED display has a response speed of 0.01ms, which means that it can deliver images up to hundreds of times faster than a mobile device equipped with an LCD (8ms), once new application processors are introduced.
As the average size of a smartphone increases,, when a consumer uses only one hand to access data, his or her finger muscle can become fatigued when accessing touch menus or icons placed on the upper part of a screen. In general, potential problems with smartphone-related conditions, such as ‘Dequervain Syndrome’, caused by straining a finger muscle and wrist, can be minimized by the use of curved displays.
Edge displays have been optimized to achieve the greatest amount of user convenience on the market today. Consumers can move the icons and menus that they most frequently use to an Edge screen so that their favorites can be easily touched with just one hand, reducing finger fatigue by as much as 20 times over.
The era of Big Data is upon us, and the amount of available information is exploding. Under these circumstances, there is a high possibility that conveying information through a side of a device that had previously been considered ‘dead space’ will become a highly popular trend. Through the use of bended or flexible display technology, text messages, news and weather information can now be rapidly accessed over a smartphone’s edge screen which previously was wasted.
There is seemingly no limit to the growing number of areas of mobile electronics in which Flexible AMOLED technology can be applied. In the future, more and more consumer products such as the rapidly growing number of wearable devices and other entry devices to the Internet of Things will embrace the usefulness and attractiveness of flexible display curvature and the vibrant, feature-rich world of OLED imagery.