LG Display's 55-inch OLED train window with a transparency of 40 percent can display operation information, advertisements and entertainment content. China has already adopted transparent OLED displays, while Russia and Japan are pushing for the introduction of window advertising. The panel is strong against impact and vibration by applying special tempered glass to suit high-speed trains.
In South Korea, luminous window ads on the exterior of transportation are prohibited due to comprehensive regulations, so the introduction of subway ads using transparent OLEDs has been delayed. In a policy change announced on August 30, the Office for Government Policy Coordination selected cases for regulatory innovation and approved an advertising method using the new technology in subways.
Based on an authoritative interpretation by a related government agency, the office made it clear that that "subway advertisements using transparent OLED displays are not subject to regulation." The decision came two months after LG Display showcased its transparent OLED window at a railroad technology trade fair in the southern port city of Busan.
LG Display provides a lineup of LED and OLED signage, transparent or not. Transparent OLED screens display black content as transparent, allowing designers to overlay digital content such as images, text and video onto real-life objects placed behind the transparent screen. LG officials suggest transparent OLED can be widely used in various places such as hotel check-in counters, museums, subways, stores, self-driving cars and aircraft cabin interiors because they do not need backlights.
LG's transparent OLED was adopted for the windows of subway cars in three Chinese cities, Beijing, Shenzhen and Fuzhou, showing traffic information and daily life information such as weather forecasts and news. The East Japan Railway Company, a major passenger railway company in Japan, agreed to introduce LG Display's transparent OLED windows.