A head and eye tracking apparatus utilizes a plurality of coded IR emitte mounted in a reflective surface, as a reference base. A reference lens aligned with the user's head references a limited number of the emitters within its field of view and transmits the image to a fiber optic bundle. Simultaneously,...http://www.google.fr/patents/US4568159?utm_source=gb-gplus-shareBrevet US4568159 - CCD Head and eye position indicator
