Optic refractive index measuring apparatus

Abstract

Abstract PURPOSE:To enable guaranteeing of accurate inspection of eyes by making a processing with a judgement that an error exists when an axial deviation between an optical system optical axis of a measuring light during the projecting of the measuring light and an optical axis of an eye to be inspected exceeds a reference value. CONSTITUTION:A projection pattern is given as a pattern of four spots facing one another sandwiching optical axes a1 and aE on a horizontal diameter and a vertical diameter on a cornea passing through the optical axis aE of an eye E to be inspected. Therefore, an optic refractive index of the eye to be inspected can be learned by measuring coordinates (Sx0, Sy0) and (Sx0, Sy9) of points S0 and S9 of an image formed on a light receiving sensor with an image recognition device corresponding to images at two points P0 and P9 on a horizontal (x) axis and on a vertical (y) axis a projected onto a cornea E1 by the spot pattern. When there is an axial deviation as angular deltaand horizontal x deviations between a measuring system optical axis a1 and the optical axis aE of the eye to be inspected, a spot image on the light receiving sensor is detected being affected by aberration or the like with the axial deviation exceeding x=+ or -1mm and delta=+ or -10 deg. thereby making correction unable to make. That is, a calculated value obtained is not adopted being regarded as unreliable.

Inventors

• 👤 Masakatsu Iwamoto
• 👤 昌克 岩本

Bibliographic Details