Navarro R, Moreno E, Dorronsoro C
Instituto de Optica Daza de Valdés, Consejo Superior de Investigaciones Científicas, Madrid, Spain.
J Opt Soc Am A Opt Image Sci Vis. 1998 Sep;15(9):2522-9. doi: 10.1364/josaa.15.002522.
The monochromatic aberrations of the human eye along the temporal meridian are studied by a novel laser ray-tracing method. It consists of delivering a narrow laser pencil into the eye through a given point on the pupil and recording the aerial image of the retinal spot with a CCD camera. The relative displacement of this image is proportional to the geometrical aberration of the ray (laser pencil) at the retina. We scanned the pupils of four observers in steps of 1 mm (effective diameter, 6.7 mm) and for five field angles (0 degree, 5 degrees, 10 degrees, 20 degrees, and 40 degrees). In addition, the aerial image for each chief ray is a low-pass-filtered version of the retinal point-spread function corresponding to a fully dilated pupil. The resulting spot diagrams, displaying the distribution of ray aberrations, are highly correlated with these point-spread functions. We have estimated the wave-front error by fitting Zernike polynomials (up to the fifth order). Despite the large variation found among observers, the overall rms wave-front error is relatively homogeneous. At the fovea, the average rms value was 1.49 microns when the second-order terms (defocus and astigmatism) were considered; this was reduced to 0.45 micron when the second-order terms were ignored. The rms values increase slowly, in a roughly linear fashion with eccentricity, such that at 40 degrees they are approximately double. These results are consistent with previous findings on the off-axis optical quality of the eye.
采用一种新型激光光线追踪方法研究人眼沿颞侧子午线的单色像差。该方法包括通过瞳孔上的一个给定点向眼睛发射一束窄激光束，并使用电荷耦合器件（CCD）相机记录视网膜光斑的空中图像。该图像的相对位移与视网膜上光线（激光束）的几何像差成正比。我们以1毫米步长（有效直径6.7毫米）对四名观察者的瞳孔进行扫描，并针对五个视场角（0度、5度、10度、20度和40度）进行测量。此外，每个主光线的空中图像是对应于完全散瞳的视网膜点扩散函数的低通滤波版本。所得的散斑图显示了光线像差的分布，与这些点扩散函数高度相关。我们通过拟合泽尼克多项式（最高到五阶）来估计波前误差。尽管观察者之间存在很大差异，但总体均方根（rms）波前误差相对均匀。在中央凹处，考虑二阶项（离焦和散光）时，平均均方根值为1.49微米；忽略二阶项时，该值降至0.45微米。均方根值随偏心率以大致线性的方式缓慢增加，使得在40度时约为两倍。这些结果与先前关于眼睛离轴光学质量的研究结果一致。
