What is Hawk-Eye and when was it first used in tennis?
Hawk-Eye™ is an officiating tool, intended to assist human line judges by providing an impartial second opinion on close line calls. Hawk-Eye uses a series of computer-controlled cameras, up to ten in total, placed around the court to gather information on the speed and trajectory of the ball. Using triangulation or, in other words, by determining the location of a point by forming triangles to that point from other, known points and measuring the angles of the triangles, Hawk-Eye constructs an animation of the most likely path, statistically, of the ball.
If a player challenges a line call, the animation can displayed on a screen, which can be seen by everyone involved, including spectators, to remove any doubt about whether a ball has bounced in or out. Hawk-Eye uses an algorithm, or a series of computer instructions, to estimate where a ball should have landed but, while it is not infallible, it is accurate to within a few millimetres and approved by the ITF, which employs the technology in 80 tournaments worldwide.
Hawk-Eye technology was first employed in a tournament sanctioned by the International Tennis Federation (ITF) at the Hopman Cup in Perth, Western Australia and in a Association of Tennis Professionals (ATP) and Women’s Tennis Association (WTA) Tour event at the Miami Open, formerly the NASDAQ-100 Open, at Key Biscayne, Florida in 2006. The U.S. Open, later in 2006, was the first ‘Grand Slam’ event to use Hawk-Eye technology.