Eye-gaze interaction: A new media – not just a fast mouse

Tracking the gaze of a person has been possible for several decades. Until recently, it was mostly done in psychological investigations of perceptual or cognitive processes, for example when driving a car or reading a text. Within the HCI area, recordings of fixation patterns have been used to analyze computer displays and support usability evaluations. Initially, the eye tracking equipment was large and expensive, and required the user’s head to be fixed, either in a frame or by using a bite-bar, and data would typically be analyzed post hoc. This state of affairs has changed. In the 1970’s, military research first combined displays with eye tracking for guiding missile systems, thus freeing the pilot’s hands for other tasks. It naturally required on-line processing of the tracking data to let the pilot use the eyes as an extra output channel. In the 1980’s, the on-line processing of eye-gaze tracking data was extended to user-interfaces for other purposes, e.g. for disabled people (especially quadriplegics). Some of the systems now available are totally unobtrusive and allow for (small) head movements. This makes them a possible candidate for enhancing interface interaction in general. Traditional direct control interface may be operated by the eyes. This speeds up the interaction and can possibly remove muscle strain caused by mouse operations. It is not possible t