Abstract: A system and method for eye tracking includes receiving an input image including at least a portion of a person's retina, finding a spatial transformation between the input image and a reference image, the reference image including at least a portion of the person's retina and calculating a change in orientation of an eye of the person corresponding to the spatial transformation. A processor may calculate, from the change in orientation an orientation of the person's eye associated with the input image, a direction of gaze associated with the input image, a gaze target associated with the input image and/or a ray of gaze associated with the input image.