Hot Spot (cricket)

Hot Spot is an infra-red imaging system used in cricket to determine whether the ball has struck the batsman, bat or pad. Hot Spot requires two infra-red cameras on opposite sides of the ground above the field of play that are continuously recording an image. Any suspected snick or bat/pad event can be verified by examining the infrared image, which usually shows a bright spot where contact friction from the ball has elevated the local temperature. Where referrals to an off-field third umpire are permitted, the technology is used to enhance the on-field umpire's decision-making accuracy. Where referrals are not permitted, the technology is used primarily as an analysis aid for televised coverage.

Its principal application in cricket is in deciding whether the ball has struck the batsman's bat or pad – this determination being critical in determining if a batsman is out or not on appeal for LBW or caught.

In considering whether a batsman is out when the ball strikes bat then caught by a member of the fielding team or caught in front of the stumps when ball hits pad, one of the most difficult decisions is whether the ball struck the pad only, or the bat only, or (if it struck both) whether the pad or the bat was struck first. If the ball strikes the bat only, or strikes the bat followed by the pad, then the batsman could be out caught but not LBW. If the ball strikes the pad in front of the stumps or inline with stumps, then the batsman could be out LBW but not caught. If the ball strikes the pad followed by the bat, then the batsman could be out LBW or out caught if a fielder catches the ball. The batsman's bat and pad are often close together, and it can be very hard to determine by eye which was struck first, whereas the hotspot technology can often resolve the question.

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