HAWKEYE

  Paul Hawkins, who introduced his invention to the Wimbledon commentary team in 2002, to explains how it works:

"There are five high-speed cameras high up in the roofs of Centre Court and Court One which accurately track the ball as it flies through the air," says Hawkins.

"A computer captures the image from each camera and works out where the ball is.

"By finding the ball in multiple cameras we can find out where the ball is in 3D space - where it is in the real world if you like.

"The computer then combines all this information and traces the trajectory of the ball in each rally.

"This information is then sent to the virtual reality machine which produces the graphic images that you see on the television.

"So Hawk-Eye is able to show where the ball landed in every point played."

"The bounce mark of the ball that Hawk-Eye shows is accurate to 3mm," explains Hawkins.

"We also take into account the amount the ball compresses and skids on the court.