| 摘要 |
PROBLEM TO BE SOLVED: To accurately measure eye refractivity by projecting measuring targets at designated spaces on the eyegrounds of an eye to be examined, removing the adjusting force of the eye and then measuring the eye refractivity. SOLUTION: First, to remove the adjusting force of an eye to be examined, a line of fixation mark is fogging-operated by a driving circuit 76, and after the end, the eye refractivity of the eye is preliminarily measured. According to the result of preliminary measurement, the measuring target is moved by the driving circuit 76, a light emitting diode 200 is forced to pulse-emit light at designated intervals (t) by a light emission control circuit 200', thereby forming a measured target image on a photo detecting element 5. A control unit 71 continuously measures the spherical degree S of the eye to the examined according to the pattern information to judge whether the change amountΔS of the spherical degree S per time intervalΔt is smaller than a designated value (e.g. 0.5) or not. WhenΔS/Δt<=0.5 is decided, it is considered that the adjusting force of the eye to be examined is enough removed, and the final measurement for the spherical degree, the astigmatism degree and the astigmatism axis is made to be displayed on a screen of a display unit 72.
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