Hotspot Technology in Cricket: Detecting Edges with Infrared
Hotspot uses infrared cameras to detect heat from ball-bat or ball-pad contact. Learn how it works, when it is used in DRS, and why it sometimes misses thin edges.
What Is Hotspot?
Hotspot is an infrared imaging system that detects heat generated by friction when the cricket ball makes contact with the bat, pad, glove, or body. When the ball grazes any surface, a small white heat signature appears on the infrared image — visible in the DRS replay.
How It Is Used in DRS
Hotspot is used primarily for caught-behind decisions and bump-ball catches. When a batter appeals against an LBW or a caught-behind decision is reviewed, the third umpire checks the Hotspot frame-by-frame to see if there is a heat mark on the bat edge. Presence of a mark suggests contact; absence suggests no edge.
Why Hotspot Is Not Always Available
Hotspot requires dedicated infrared cameras and is not universally deployed. It is costly and not all venues or broadcast contracts include it. Some matches use Snickometer (Ultra Edge) instead, and some use both. The ICC does not mandate Hotspot for all DRS matches.
Famous Hotspot Controversies
During the 2013 Ashes series, several decisions were disputed when Hotspot missed thin inside edges off the bat onto the pad — showing no mark despite audible noise. These controversies prompted research into why Hotspot missed these contacts, leading to refinements in how Ultra Edge is used alongside it.
Frequently asked questions
Can sunscreen fool Hotspot?
It is theorised that sunscreen or silicon-based substances on the bat edge can prevent heat generation on contact with the ball, causing Hotspot to miss a genuine edge. This was debated in the 2013 Ashes but never confirmed conclusively.
Is Hotspot used in T20 cricket?
Hotspot is available in T20 internationals where the host broadcaster has the cameras deployed. It is less commonly available than in Test cricket due to cost.
What is the difference between Hotspot and Snicko?
Hotspot uses infrared imaging to show heat marks from contact. Snicko (Ultra Edge) uses an audio waveform to detect the sound of bat-ball contact. They are complementary technologies used together in DRS.