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Cyclops and speed guns
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Cyclops can tell if a ball's in or out
You cannot be serious!

What's a one-eyed monster from Greek mythology got to do with tennis?

Well, this Cyclops is a system of infra-red beams which is used to help determine whether serves are in or out.

With top players serving at speeds of over 140mph, this can be very difficult to detect with the naked eye.

Cyclops has been used at Wimbledon since 1980.

It's also used at other major championships such as the US Open and Australian Open.

What does it look like?

The box, which is placed at the side of the court, measures around 6cms high, 45 cms long and 20cms wide.

It can take around four hours to install.

How does it work?

The Cyclops box projects a horizontal array of five or six light beams across the court, 10mm above the ground.

It makes the loud beep noise you can hear whenever the ball breaks the beams situated beyond the service line.

Can it make the wrong call?

The system is constantly being improved.

The one currently in use is the 10th version and is more resistant to being triggered by insects flying in front of the beams than older versions.

Clock that!

Lleyton Hewitt's serve is measured at 117mph during last year's Wimbledon
Hewitt's serve clocks 117mph

Not even the biggest hitters in tennis are a match for the IBM radar gun used at Wimbledon.

The radars measure the speed of service throughout the tournament.

However fast the players serve, the IBM gun can always match the speed - even if their opponents can't.

How does a radar gun work?

During Wimbledon, two specially designed radar sensors are positioned behind the baseline at either end of the Centre Court, as well as the number one, two, three, 13 and 18 courts.

Once a player strikes the ball, the radar guns detect its speed.

The information is flashed up on the court-side screens.

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New balls please
Making a racquet
Cyclops and speed guns
Eye on the future

Ace fact
In Greek mythology, Cyclops is a one-eyed monster
The fastest servers during the 2002 Championships were Andy Roddick (144mph) and Venus Williams (119mph)
Cyclops was invented by a former aircraft engineer called Bill Carlton. He also invented the plastic shuttlecock

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