How do you choose a panel technology for a display that's bigger, at 10 by 10 meter, than the side of a barn? The liquid-crystal and plasma technologies used in large-screen home TVs are out of the question. CRTs are out too, and organic electroluminescence doesn't even merit mention as a candidate.
There is only one existing technology that can be tapped to display images large enough for arena use and are viewable even in direct sunlight, the light emitting diode or LED´s: LED displays and LED screens
With displays sizes varying from a small LED display screen of 2 square meters upto 8 square kilometers or more, it wont make a difference. Because LED displays are modular screens, you can multiply the size of the large LED screens by adding more cabinets to it and expand the total size, quality and improve the total resolution without having any troubles.
Building humongous panels is very difficult. Today, the largest LCD that can be manufactured is 108 inches on the diagonal. For plasma display panels (PDP´s), the largest possible screen size is 150 inches (diagonal). To go larger than that, special production equipment would have to be developed.
Projection technology might seem like a solution, but it's not. Indoors, front-projection is feasible. But in big, enclosed arenas such as those at the Beijing Olympics, the presence of competing light sources tends to dull the projected images. Naturally, things get even worse for a front projector in an outdoor stadium.
That´s why LED video displays and LED screens are the solution if you want to go large.
One advantage of the LED´s, self-emitting diodes, is that it's easy to increase the brightness of the LED screen.The luminance is as high as 5,000 to 8,000 candelas/ square meter; the brightest PDP can offer only 1,600 cd/m2. And the LED panels are not flat, so slanting sunlight is deflected to the ground and away from the audience. That isn't possible with LCD or plasma flat panels.
A LED display screen installed in an arena must be able to deliver excellent images to the audience regardless of where they sit. Here too, LED displays have advantages.
Because a LED display screen consists of a number of LED units, each serving as light source, it can offer a horizontal viewing angle as wide as 150°. Further, there is hardly any color degradation in images on the screen, regardless of angle. A spectator viewing a 10 x 10 meter LED display screen can clearly see not just moving images, but also race results and athletes' names on the screen from as far away as 200 meters.