| 摘要 |
PROBLEM TO BE SOLVED: To make measurable accurately and fast the refractive power of even unstable eyes of infant, etc., by providing a light pattern on the eyeground of an eye to be measured, detecting the reflected light, analyzing a light reception signal with a diaphragm member installed on the midway of an optical system that guides the reflected light, and computing the refractive power of the examined eye. SOLUTION: The image of an eye to be examined is picked up with a CCD camera 250 and projected on a TV monitor, and measurement is performed while watching the image. In other words, first the phases of two pairs of light receiving elements for measuring refraction in a detection means 73 are measured, and from the phase difference, the first stage refractive power of the examined eye and an equivalent spherical refractive power are computed. And then a fixation sign 68 and a visible lighting light source 74 are moved optically farther than the equivalent spherical refractive power by a prescribed amount and a moving diaphragm 75a is moved to a position equivalent to the equivalent spherical refractive power of the light receiving optical system. In addition, by executing the second stage measurement, the phases of the two pairs of refractive power measuring light receiving elements are measured again, and the refractive power of the examined eye is computed from diaphragm displacement data and a phase difference output signal.
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