An eye tracker is a device that tracks eye movements. Most eye trackers today implement computer vision algorithms to detect and track eye movements using video cameras pointed to one or both eyes of the user.
Two camera setups are commonly available: remote and head mounted eye trackers. In remote eye trackers, the camera is placed near the display used for gaze interaction. In head mounted eye trackers, the eyes are tracked by near eye cameras and eye gaze is typically computed on the image of a scene camera.
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