Patent US 6,607,527

An eye laser system which includes a laser and a laser delivery system for delivering a laser beam generated by the laser to the eye and an eyetracking system which monitors movement of the eye and conveys eyetracking information to the laser delivery system with the eyetracking system including a non-invasive eye tilt reference marker. The reference marker projects an energy beam that is preferably visible so as to reflect off the iris of the eye and provide microscope and surgical field illumination. The reference marker includes a plurality of points arranged concentrically about the pupil of the eye and/or a concentric ring marking device. This arrangement provides information as to eye tilt for use in, for example, video frame review during an initial reference setting or a subsequent eye tracking stage. Also described are laser delivery systems including an eye tilt accommodation laser delivery systems that are well suited for use with the eyetracking system described above which provides an indication of eye tilt and provide data sufficient for determining an angle of eye tilt and hence an angle required by the laser accommodating system to provide a laser beam coincident with the axis of tilt for a tilted eye.