Mitsubishi Electric hopes to soon see buildings, trains, and buses in Japan plastered with its flexible OLED displays.

The Diamond Vision OLED screen, which is on display at the Ceatec exhibition in Chiba, Japan, is a modular display made up of small OLED (organic light-emitting diode) screens. Each screen contains separate red, blue and green OLED that function as pixels in the display. Up close, the display is a matrix of flashing red, blue and green lights, but step back approximately 2 meters and the individual pixels merge into a larger, high-resolution image.

The Diamond Vision OLED screen offers several advantages over the large LED displays found in most major cities and large sports stadium. For starters, the OLED screen can display an image that has a much higher resolution than what's possible with an LED display, said Nobuo Terazaki, the project director at Mitsubishi who led the development of the OLED screen.

The modular nature of the display means that it doesn't have to be flat. For example, a screen could easily be made that covers the side of a building that is curved, he said.

Another advantage of the screen's modular design is that there is no limit to how big the display can be made. The size of a video screen made using the displays is only limited by the resolution of the image, such as a high-definition video. But for advertising or other application, there's no limit to how big the screen can be, Terazaki said, saying it would theoretically be possible to cover an entire city with a single display.

There's just one drawback. OLED displays are made using an organic luminescent compound that lights up when an electric current is applied. Over time, the compound degrades and the display stops working.

Mitsubishi said the Diamond Vision OLED screen is expected to have a lifespan of 20,000 hours of normal operation. That translates into roughly two years and four months of continuous operation, which makes it likely that the cost of building and operating the displays could be significantly more expensive than older LED screens, which last much longer.

Mitsubishi declined to say when the displays will be available, or how much they expect them to cost.