A Calibration Method for Eye-Gaze Estimation Systems Based on 3D Geometrical Optics

A new calibration method is presented for robust eye-gaze estimation systems which are utilized to understand the human mind. Although current eye-gaze systems with one camera and a few infrared light sources have been developed to allow users´ head motion, they still require one to know the relative positions between the camera and light sources with very high accuracy. The developed calibration method utilizes a three-dimensional geometrical relationship between the light source positions and corresponding camera images reflected on a mirror at several positions and rotations. The best estimates of the light source positions are obtained from noisy measurements by minimizing a cost function, which ensures the integrity of the camera and light sources. The developed calibration method makes it possible to convert many camera-and-display devices into robust eye-gaze estimation systems.