FoxTrax, also referred to as the glowing puck, is an augmented reality system that was used by Fox Sports' telecasts of the National Hockey League (NHL) from 1996 to 1998. The system was intended to help television viewers visually follow a hockey puck on the ice, especially near the bottom of the rink where the traditional center ice camera was unable to see it due to the sideboards obstructing the puck's location. The system used modified hockey pucks containing shock sensors and infrared emitters, which were then read by sensors and computer systems to generate on-screen graphics, such as a blue "glow" around the puck, and other enhancements such as trails to indicate the hardness and speed of shots.