| 摘要 |
PROBLEM TO BE SOLVED: To compute the amount of cut of the cornea in refractive index correction operation and carry out a more accurate operation. SOLUTION: The front of an eye to be examined is illuminated by a placido ring 71 as a second illumination optical system 70, and the radius of curvature of the examined eye is obtained from reflected light from the front of the examined eye (S101). A part of illumination light is taken out by the first light source section 11 of a first illuminating optical system 10 through an optical path splitting means 41 and is let out to a reference mirror 14 as reference light. The remaining reflected light is reflected to illuminate the front of the examined eye (S103). By moving a converging optical system 90 by a converging optical system moving means 91, the point of convergence of the front of the examined eye is moved (S105). The reference mirror 14 is moved by a reference mirror moving means 16 to see the state of intervention between reflected light from the vicinity of the cornea 62 and reference light from the reference mirror 14 (S107). When the point of convergence matches the interface in which the refractive index changes, the maximum value of the envelope of an interference stripe is detected (S109). The refractive index of the cornea is computed from a signal light interval obtained (S111). The thickness of the cornea 62 is computed from the refractive index (S113). |
