Display technology has evolved from black-and-white TVs, through LCDs and PDPs, to innovative technologies like OLEDs, especially transparent OLEDs. Transparent displays are nearing commercialization, with the promise of new functions and roles in smart homes, autonomous driving, healthcare, education, 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. Early black-and-white TVs were limited in terms of screen resolution and size, and had significant limitations in terms of viewing angles and color sensitivity. However, with technological advancements, screen sizes have gradually increased, colors have become more vibrant, and screens have evolved into thinner and sharper screens. In Korea, in particular, 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’s display technology began to become globally competitive, and today it is the world’s leading player in this field, with annual exports of $34.5 billion and a 45.8% global market share.
The display industry has been limited to the TV or monitor market for decades, but its applications have been expanding with the recent popularization of smartphones and tablet PCs. The need for high resolution and low power consumption in highly portable devices has created new challenges for display technology, which has led to faster technological advancements. Furthermore, these display devices are being used in wearable devices, such as smart watches and augmented reality (AR) devices, and are being utilized in many aspects of our daily lives.
The movie Minority Report, which is often referenced when discussing future display technologies, shows a variety of innovative display technologies, including transparent screens, 3D advertising banners, and display newspapers. The technologies in the movie were based on real technologies being researched at MIT at the time, and now, more than a decade after the movie’s release, the movie’s imagination is being realized. Some of the future display technologies currently being researched include transparent displays, flexible displays, and ultra-low-cost displays. These technologies are revolutionizing not just visual pleasure, but also information delivery, convenience, creativity, and more.
Transparent displays have long been in the spotlight due to their unique ability to show information naturally with a background. However, they were initially difficult to commercialize due to high manufacturing costs, low durability, and optical limitations. The commonly used liquid crystal display (LCD), a technology that enables images by controlling the light transmittance of a material that is in an intermediate state between a solid and a liquid, called a liquid crystal, requires a pair of polarizers and an optical film, which severely limits its transparency. It is also backlight-based, which makes it difficult to achieve full transparency.
However, recent advances in active organic light-emitting diodes (AMOLEDs) are gradually addressing 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 emissive layer is typically transparent, a transparent OLED can be realized if both electrodes are transparent. In particular, AMOLEDs are mainly used in high-end electronic devices because they can realize low power consumption and high resolution compared to PMOLEDs, and the technology is playing a pivotal role in driving innovation in the display industry.
AMOLED-based transparent displays have great potential for applications in a variety of industries. For example, in smart home technology, windows can be made into transparent displays to act as “smart windows” that show weather, time, news, and more, providing real-time indoor and outdoor information to enhance the user experience. In the automotive industry, augmented reality displays are also being developed to show real-time driving information on windshields and side mirrors, which could be used in future vehicles to provide both safety and convenience.
These applications demonstrate that transparent displays can go beyond simply replacing traditional display technologies and contribute to completely new functions and roles. Furthermore, once commercialized, transparent displays have the potential to be used in a variety of ways in education, healthcare, advertising, and more. For example, hospitals can display a patient’s condition on a transparent screen in real time to improve the efficiency of medical staff, while museums and art galleries can display relevant information transparently on top of their exhibits.
Innovative technologies such as transparent displays have already been showcased at various flat panel display trade shows since 2009, and commercialization is expected to be just around the corner. In fact, some market researchers estimate that full-scale commercialization will begin in 2024, with the market reaching around KRW 32 trillion by 2030. The future of display technology is not just about increasing screen resolution, but is gradually expanding into new areas where displays have not been used before. These changes are expected to go beyond technological innovation and change our daily lives.
