Atchison D A, Woods R L, Bradley A
Centre for Eye Research, School of Optometry, Queensland University of Technology, Kelvin Grove, Australia.
J Opt Soc Am A Opt Image Sci Vis. 1998 Sep;15(9):2536-44. doi: 10.1364/josaa.15.002536.
We used diffraction modulation transfer functions and model eyes to predict the effect of defocus on the contrast sensitivity function (CSF) and compared these predictions with previously published experimental data. Using the principle that optically induced changes in the modulation transfer function should be paralleled by identical changes in the CSF, we used the modulation transfer function calculations with the best-focus CSF measurements to predict the defocused CSF. An aberration-free model predicted the effects of defocus well when the CSF was measured with small pupils (e.g., 2 mm) but not with larger pupils (6-8 mm). When the model included average aberrations, prediction of the defocused CSF with large pupils was better but remained inaccurate, failing, in particular, to reflect differences between individual subjects. Inclusion of measured aberrations for individual subjects provided accurate predictions in the shape of the monochromatic CSF of two of three subjects with hyperopic defocus and good predictions of the polychromatic CSF of two subjects with hyperopic defocus. Prediction of the effects of myopic defocus by use of measured individual aberrations of one subject were less successful. Hence a diffraction optics model can provide good predictions of the effects of defocus on the human CSF, given that one has knowledge of the individual ocular aberrations. These predictions are dependent on the quality of the aberration measurements.
我们使用衍射调制传递函数和模型眼来预测散焦对对比敏感度函数（CSF）的影响，并将这些预测结果与先前发表的实验数据进行比较。利用光学诱导的调制传递函数变化应与CSF中相同变化相对应的原理，我们使用最佳聚焦CSF测量的调制传递函数计算来预测散焦的CSF。一个无像差模型在使用小瞳孔（例如2毫米）测量CSF时能很好地预测散焦效果，但在大瞳孔（6 - 8毫米）时则不然。当模型包含平均像差时，大瞳孔散焦CSF的预测更好但仍不准确，尤其无法反映个体受试者之间的差异。纳入个体受试者的测量像差能准确预测三名远视性散焦受试者中两名的单色CSF形状，并能较好地预测两名远视性散焦受试者的多色CSF。利用一名受试者的测量个体像差预测近视性散焦的效果则不太成功。因此，鉴于了解个体眼像差，衍射光学模型可以很好地预测散焦对人CSF的影响。这些预测取决于像差测量的质量。
