Along with about 20,000 rounds of fireworks, a 280m-wide LED screen commanded attention at the opening ceremony of the Expo 2010 Shanghai China, which took place in the night of April 30, 2010.
In the daylight, the scene behind the screen can be seen through because its "pixel pitch" is as wide as about 12cm.
When closely looked at, the screen has a structure in which light emitting devices using LEDs are arranged on a frame such as used at construction sites. This is one of the reasons why only 249,480 light emitting devices are used for the gigantic screen.
The luxurious opening ceremony that China hosted by staking its prestige seems to have been supported by surprisingly low-cost technologies.