Corneal shape measuring apparatus

Claim 1

A corneal shape measuring apparatus comprising: an illuminating optical system for illuminating a cornea of a subject's eye; a measuring optical system having an objective lens on which light reflected by the cornea of the subject's eye illuminated by said illuminating optical system impinges; an indicator having a visual target projected onto said cornea by said illuminating light, said indicator being disposed between said objective lens and the subject's eye; a light guide hole for guiding an image of the target reflected by said cornea to said objective lens; reflecting surfaces aligned with said guide hole, for reflecting an image of said guide hole to said objective lens; a photodetector on which said reflected target image is projected and on which the guide hole image from said reflecting surfaces is projected by reflected light; computing circuit means for calculating a shape of said reflected target image based on a corresponding signal from said photodetector, computing an inclination of the indicator with respect to a measuring axis from the shape of said guide hole previously inputted and the shape of said guide hole image, and correcting the shape of said reflected target image accordingly based on the computed inclination to determine a deformation of the cornea of the subject's eye; and display means for displaying the shape of the subject's eye obtained by said computing circuit means.