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In some hockey telecasts, the path of the puck is shown in color. How is this done?

The "FoxTrax" system (or "Glow Puck" as some people call it) began appearing on Fox televised hockey games in 1996. The technology was developed in response to one of the most common complaints television viewers had about watching hockey; namely, that it's sometimes difficult to follow the puck. With the FoxTrax system, the puck on TV glows blue during most of the play, and when the puck travels over 70 mph a red "comets's tale" appears on the screen.

The FoxTrax puck-tracking system works by using embedded infrared emitters (and a battery) in the puck and detecting them with a system of ten infrared cameras (your television remote control also uses infrared to communicate with your TV). The data is then sent to a television production truck, known as the "Puck Truck," where the graphic highlight is rendered and then combined with the broadcast camera video. The final result is the glowing puck that you see on TV.

For more in-depth (and technical) look at the technology and the story behind the development of the glowing puck, visit, " The FoxTrax Hockey Puck Tracking System " by Rick Cavallaro.

We should also mention here that many hockey purists dislike the glowing puck technology. They argue that the glowing puck is a distraction since watching a game involves more than following the puck. A number of web pages committed to the abolition of the glow puck have popped up. Check out Get the Puck Outta Here!! or The Fox Track Puck Must be Stopped .