A two dimensional fiber optic eye position sensor for tracking and point-of-gaze measurements

The optical configuration of the presented sensor consists of three imaging lenses mounted on a pair of eyeglass frames around the field of vision. This allows normal eye movement and unobstructed vision without distracting the subject. The optical sensors gather light reflected from the area of the sclera to the immediate left and right of the iris and transmit this light through optical fibers to remote detectors. The device determines horizontal position by utilizing the difference in reflectivity between the iris and sclera. Vertical position of the eye is determined similarly by monitoring either the upper or lower eyelid. Point-of-gaze and short period tracking measurements have been made in two dimensions with an accuracy of better than half a degree in the horizontal direction and three degrees in the vertical direction