Artal P, Ferro M, Miranda I, Navarro R
Instituto de Optica, Consejo Superior de Investigaciones Científicas, Madrid, Spain.
J Opt Soc Am A. 1993 Jul;10(7):1656-62. doi: 10.1364/josaa.10.001656.
The retinal image quality characterized by the modulation-transfer function of the eye was measured for two groups of subjects aged in the late twenties and mid sixties, respectively. In both groups, we obtained modulation transfer functions by using a double-pass method under the same experimental conditions: 4-mm artificial pupil, paralyzed accommodation, and objective control of the refractive state and centering. Results showed lower values of modulation in the retinal image for older subjects compared with the younger subjects. The modulation transfer function ratio is similar to that previously found for contrast-sensitivity measurements with subjects in the same age groups. These results suggest that a significant fraction of the loss in spatial vision with age has an optical origin. Apart from the well-known increase in intraocular scattering, there also appears to be an increment in ocular aberration that causes an additional reduction in the contrast of retinal images.
分别对两组年龄在二十多岁后期和六十多岁中期的受试者测量了以眼睛调制传递函数表征的视网膜图像质量。在两组中，我们在相同实验条件下采用双程法获得调制传递函数：4毫米人工瞳孔、调节麻痹以及屈光状态和对中的客观控制。结果显示，与年轻受试者相比，老年受试者视网膜图像中的调制值较低。调制传递函数比率与之前在相同年龄组受试者的对比敏感度测量中发现的比率相似。这些结果表明，随着年龄增长空间视觉损失的很大一部分源于光学因素。除了众所周知的眼内散射增加外，还似乎存在眼像差增加，这会导致视网膜图像对比度进一步降低。
