What is it?
Goal-line technology is a technical means of instantly determining whether the whole of the ball has crossed the goal line. Goal-line technology continues to be a staple in the football world since it was first implemented in 2014.
How does it work?
The technology must provide a clearly indicate whether the ball has fully crossed the line. This information will serve to assist the referee in taking their final decision. The information is transmitted within one second which ensures an immediate response from the referee. Only the match officials are receive the signal on their watches. The system uses 14 high-speed cameras mounted on the catwalk of the stadium/under the roof. The data from the cameras is used to create a 3D animation to visualise the decision to the fans on TV and on the giant screen inside the stadium.
How was it tested?
The IFAB decided on 5 July 2012 that the potential use of goal-line technology was to be implemented in the Laws of the Game and a certification procedure should control the quality of goal-line technology systems. All competition stadiums are tested by an independent test institutes before the start of the tournament. Moreover, the referee checks the system before the start of each match to see if it is turned on and correctly calibrated.
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