Opt Lett. 2013 Dec 15;38(24):5208-11. doi: 10.1364/OL.38.005208.
The purpose of the study is to measure chaos in dynamic anterior surface aberrations and examine how it varies between the eyes of an individual. Noninvasive tear breakup time and dynamic corneal surface aberrations were measured for two open-eye intervals of 15 s. The maximal Lyapunov exponent (MLE) was calculated to test the nature of the fluctuations of the dynamic anterior surface aberrations. The average MLE for total higher-order aberration (HOA) was found to be small (+0.0102±0.0072) μm/s. No significant difference in MLE was found between the eyes for HOA (t-test; p=0.131). Data analysis was carried out for individual Zernike coefficients, including vertical prism as it gives a direct measure of the thickness of the tear film over time. The results show that the amount of chaos was small for each Zernike coefficient and not significantly correlated between the eyes.
本研究的目的是测量动态前表面像差中的混沌,并研究其在个体双眼之间的变化情况。在两个 15 秒的睁眼间隔内,测量了非侵入性泪膜破裂时间和动态角膜表面像差。为了检验动态前表面像差波动的性质,计算了最大李雅普诺夫指数(MLE)。发现总高阶像差(HOA)的平均 MLE 较小(+0.0102±0.0072)μm/s。HOA 的 MLE 在双眼之间没有显著差异(t 检验;p=0.131)。对包括垂直棱镜在内的各个泽尼克系数进行了数据分析,因为它可以直接测量泪膜随时间的厚度。结果表明,每个泽尼克系数的混沌量都很小,并且双眼之间没有显著相关性。