(World Scientific Publishing, 2007) Villanueva Larre, Arantxa; Cabeza Laguna, Rafael; Porta Cuéllar, Sonia; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
In the past years, research in eye tracking development and applications has attracted
much attention and the possibility of interacting with a computer employing just gaze
information is becoming more and more feasible. Efforts in eye tracking cover a broad
spectrum of fields, system mathematical modeling being an important aspect in this
research. Expressions relating to several elements and variables of the gaze tracker would
lead to establish geometric relations and to find out symmetrical behaviors of the human
eye when looking at a screen. To this end a deep knowledge of projective geometry as
well as eye physiology and kinematics are basic. This paper presents a model for a
bright-pupil technique tracker fully based on realistic parameters describing the system
elements. The system so modeled is superior to that obtained with generic expressions
based on linear or quadratic expressions. Moreover, model symmetry knowledge leads to
more effective and simpler calibration strategies, resulting in just two calibration points
needed to fit the optical axis and only three points to adjust the visual axis. Reducing
considerably the time spent by other systems employing more calibration points renders
a more attractive model.
