| 摘要 |
<p>The automatic physical eye refraction system illustrates a test mark in the eye and by auto-collimation of the retina on a similar test mark. One at least of the marks oscillates along the optical axis, the fluctuations of the rays being converted into an electrical signal after illustration on the second mark by a photo-detector. The extreme values of this signal, whose amplitude varies with time, the time interval being equal to half the cycle of the test mark oscillation, are detected by reference impulses and evaluated for amplitude. The sum of and difference between successive measurements serve as criteria for adjustment of the equipment.</p> |
