HOW IT WORKS
And You Thought Your Neighbor Had a Jumbo TV
By MICHEL MARRIOTT
Published: December 23, 2004
 IKE
a lost scene from Ridley Scott's futuristic cult movie "Blade Runner," Times
Square soars with glittering buildings that pulse and wink with outsized
video screens.
A little more than a decade ago, there was only one, the Sony
Jumbotron, which anchored the southern end of the square. Now billboard-size
screens are commonplace. The newest went into service last month. Its designer,
Mitsubishi Electric
Power Products' Diamond Vision division, says it is one of the largest outdoor
full-color high-definition video screens in the world. | Advertisement
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Mounted
in a giant picture frame on Seventh Avenue between 44th and 45th Streets,
the screen is 21 feet 5 inches high by 37 feet 9 inches wide and about 4
feet deep, although most of the depth is taken up by the catwalks used to
service it. With a screen area of about 800 square feet, it's about 80 times
bigger than the largest home TV's. The screen, across Times Square from the glass-walled studios of MTV, the Viacom
division that owns it, can broadcast music videos, news, content from MTV's
Web site and live events taking place in the studio and elsewhere. Next
month, an interactive feature will be added: pedestrians will be able to
use their mobile phones to play along with programs on the screen, including
text-message-based video games. And MTV executives say they are considering
ways to enable viewers to hear the screen's offerings as well, either over
low-power radio broadcasts or by dialing a special number on a cellphone.
Akira Tasaki, president and chief executive of Mitsubishi Electric
U.S., said the high-definition display, which at its core consists of more
than two million light-emitting diodes, is among his company's most technologically
sophisticated screens. For one thing, because it is a true high-definition
screen - like more and more of the fanciest sets sold for home use - it displays
images at 1080i resolution, meaning it paints the screen with 1,080 lines
in two passes - interlaced - 30 times a second. That's more than twice the
number of lines a standard-definition screen has. Each of the 1,080 lines
in the HDTV screen consists of 1,920 pixels, the smallest element of an image.
At the scale of the MTV screen, those pixels are created by a bouquet of
L.E.D.'s that can be controlled to produce any color. On the MTV screen,
the L.E.D.'s are closely arranged in a quad pattern of two red dots, one
green and one blue. This arrangement becomes important, said David
Corathers, the engineering manager for Diamond Vision, because it permits
the screen to manipulate dots, creating a sort of intermediate dot he calls
a dynamic pixel. This, Mr. Corathers said, helps to render sharper pictures
than typical L.E.D. screens display. The screen also requires "fewer pixels to create something that looks much, much higher in resolution," Mr. Corathers said. Another
digital technology, called color space conversion, compensates for and corrects
the tendency of large L.E.D. screens to produce oversaturated colors, making,
for instance, red appear more like hot pink. The screen's specially
color-tuned L.E.D.'s are mounted in a panel called a lighting unit. The lighting
units are then arranged 34 high by 30 wide to create the screen that has
a 16:9 aspect ratio, sometimes known as letterbox. The units also
have custom-made louvers, removable eyelids of sorts that can be used to
improve the screen's viewing angle and that help maintain contrast even in
bright sunlight. Like most outdoor video screens, the MTV screen has to be
viewed in varying lighting conditions. While many large L.E.D. screens
are driven by off-the-shelf personal computers that process their content,
Mark Foster, general manager for Diamond Vision, said the MTV screen uses
high-capacity custom processors linked to MTV's studios by a fiber-optic
cable.
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