On-line adjustment of dwell time for target selection by gaze

In eye typing systems, a dwell time that adjusts to the user's natural typing speed is highly desirable. We present an algorithm for on-line adjustment of dwell time developed after detailed analysis of exit time upon selection of virtual keys. Exit time was measured using a wide range of dwell times for key selection (300-1100 ms). The results suggest that there was considerable variability in exit time among users indicating the need for calibration of the algorithm. The algorithm was evaluated in a user study and proved to be efficient. We also discuss the shortcomings of the current algorithm's implementation.