Villegas Eloy A, Alcón Encarna, Artal Pablo
Laboratorio de Óptica, Instituto Universitario de investigación en Óptica y Nanofísica (IUiOyN), Universidad de Murcia, Campus de Espinardo (Edificio 34) 30100 Murcia, Spain.
J Opt Soc Am A Opt Image Sci Vis. 2012 Aug 1;29(8):1667-72. doi: 10.1364/JOSAA.29.001667.
When the eye's higher-order aberrations are measured and reported, as important as the magnitude of each individual term are the possible combinations between them, which may change the overall retinal image quality and therefore visual performance. We have evaluated the relationships among different aberration terms in the human eye-coma, trefoil, and spherical aberration-and their effects on both retinal image quality and visual acuity (VA). In a group of normal young subjects with normal to excellent vision, we measured the eye's aberrations and high contrast VA under natural conditions after carefully correcting defocus and astigmatism. Among the different combinations of aberration terms, we only found a significant negative correlation (r2=0.30) between the vertical coefficients of trefoil C(3,-3) and coma C(3,-1). This is a positive coupling that produces a better retinal image quality than any of the other possible combinations of these terms. However, this improvement in image quality is limited by the presence of other aberrations. Only in a few eyes that presented the larger values of coupled vertical trefoil and coma appeared a significant improvement of image quality. Although we did not find a clear correction between the coma-trefoil vertical coupling and VA, most eyes with large amounts of aberrations (RMS>0.4 μm) have these terms coupled, keeping decimal acuity around 1.2 or higher.
当测量并报告眼睛的高阶像差时，与每个单独像差项的大小同样重要的是它们之间可能的组合，这些组合可能会改变整体视网膜图像质量，进而影响视觉性能。我们评估了人眼不同像差项（彗差、三叶草像差和球差）之间的关系，以及它们对视网膜图像质量和视力（VA）的影响。在一组视力正常至极佳的年轻正常受试者中，我们在仔细校正了散焦和散光后，于自然条件下测量了眼睛的像差和高对比度视力。在像差项的不同组合中，我们仅发现三叶草像差的垂直系数C(3,-3)与彗差的垂直系数C(3,-1)之间存在显著负相关（r2 = 0.30）。这是一种正耦合，相较于这些项的任何其他可能组合，它能产生更好的视网膜图像质量。然而，图像质量的这种改善受到其他像差存在的限制。只有在少数呈现出较大垂直三叶草像差与彗差耦合值的眼睛中，才出现了图像质量的显著改善。尽管我们未发现彗差 - 三叶草像差垂直耦合与视力之间存在明确的校正关系，但大多数像差较大（均方根 > 0.4 μm）的眼睛都存在这些项的耦合，小数视力保持在1.2或更高。
