How will transparent display technology change our future?

Transparent display technology, made possible by advances in AMOLEDs, is enabling immersive augmented reality in personal electronics, vehicles, advertising, and more.

 

From the first black-and-white TVs in the 1960s, to PDPs, LCDs, and now 3D TVs, which are slowly rising to the surface, display technology has evolved alongside the medium of television. In Korea, large companies have invested heavily in the display industry, starting with LG Electronics’ original development of a 40-inch PDP TV in 1997. As a result, Korea now has the world’s leading position in this field, with annual exports of $34.5 billion and a 45.8% global market share. After decades of being limited to the TV or monitor market, the display industry is now developing more rapidly thanks to the growth of the smartphone and tablet PC markets. How will display technology expand and evolve in the future?
The movie “Minority Report” is always mentioned when talking about future display technology, with transparent screens, 3D advertising banners around you, and display newspapers throughout the movie. The technologies in the movie are made up of technologies that were being researched at MIT at the time, and now, more than a decade after the movie’s release, most of them are taking shape. Some of the future display technologies that are currently being researched include transparent displays, flexible displays, and ultra-low-cost displays.
Among these, transparent displays have been attracting attention for their ability to show information against a background, but their development has been hampered by technical limitations. The LCD (Liquid Crystal Display) method, which was mainly developed until now, is a display technology that displays images by controlling the light transmittance of a substance that is in an intermediate state between a solid and a liquid called a liquid crystal. Although liquid crystals themselves are transparent, the LCD method required a pair of polarizers and various optical films, which resulted in a transmittance of around 6%, and the use of backlighting rather than self-lighting, which inherently limited the ability to create transparent displays.
However, recent rapid advances in active organic light-emitting diodes (AMOLEDs) have made it possible to overcome these limitations. OLEDs work by injecting electrons and holes into both sides of an organic light-emitting layer, which then combine within the organic light-emitting layer to produce light. Since the organic light-emitting layer is typically transparent, making both electrodes transparent can create a transparent OLED. In particular, active organic light-emitting diodes (AMOLEDs) are more expensive than passive ones (PMOLEDs), but they operate at lower voltages and have higher resolution, so they are being researched more actively.
Transparent displays using AMOLEDs are expected to find applications in personal electronics, automotive and aviation, advertising, and many other fields. Essentially, the ability to see through the background will enable immersive augmented reality in many applications. In addition to personal electronic devices, it can be used for smart glass windows that adjust the brightness of sunlight, displaying current driving information, road conditions, navigation, etc. on the windshield, rearview mirror, and cluster of a car, displaying information in department stores, and providing information in public spaces.
In some of these applications, transparent displays have replaced conventional displays, but most of them are areas where displays have not been used before. Therefore, transparent displays can create a market for displays in other areas that we have not thought of. Therefore, the development of transparent displays in various fields that can be applied together will have a greater impact.
Technologies such as transparent displays have been announced at various flat panel display fairs since 2009 and are expected to be commercialized in earnest from 2024. The market size is expected to reach 32 trillion won by 2030. The future of display technology is not just about higher resolution, but is expected to overcome the limitations of displays and expand their applications to penetrate previously unthinkable fields.