APPARATUS AND METHOD FOR DETERMINING CORNEAL AND SCLERAL TOPOGRAPHY

An apparatus and method for determining the topography of the cornea and sclera that permit the detailed determination of the topography of the entire visible corneal and scleral surfaces; the topographic data so obtained is readily and conveniently accessible to the opthalmic practitioner or surgeon. A fluorescent substance instilled in the tear layer of the eye, and hence the surface of an eye, is made to fluoresce in a small, selected area of the eye surface by an incident light beam defining the selected area of the eye surface. The location of the selected area can be known from the position and direction of the incident light beam. The selected area's location is measured from at least one additional orientation different from that of the incident light beam by focusing an image of the fluorescence emissions from the selected area onto the surface of a positive sensitive detector. The elevation of the eye surface in the selected area is determined by triangulation or profiling, depending on the direction of the fluorescence detection. A plurality of such measurements made at different locations on the surface of the eye permits the topography of the corneal and scleral surfaces of the eye to be determined.