A non-stationary model for simulating the dynamics of ocular aberrations.

The time-evolution of ocular aberrations has been the subject of many studies, but so far there has been little discussion involving the modelling of the underlying temporal statistics. This paper presents a non-stationary modelling approach based on a coloured-noise generator, which can be applied to ocular aberration dynamics. The model parameters are computed from measured ocular aberration data. A custom-built aberrometer based on a Shack-Hartmann sensor was used for measurement. We present simulations based on our modelling approach, and validate them through comparison to real data. This work could be useful in areas such as the testing of ophthalmic devices and the development of improved algorithms for laser refractive surgery.

[1]  Paul B. Colditz,et al.  Nonlinear nonstationary Wiener model of infant EEG seizures , 2002, IEEE Transactions on Biomedical Engineering.

[2]  P Artal,et al.  Dynamics of the eye's wave aberration. , 2001, Journal of the Optical Society of America. A, Optics, image science, and vision.

[3]  Mingxia Zhu,et al.  Microfluctuations of wavefront aberrations of the eye , 2004, Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians.

[4]  Pascal Puget,et al.  Study of the dynamic aberrations of the human tear film. , 2005, Optics express.

[5]  Christopher Dainty,et al.  Weak correlation between the aberration dynamics of the human eye and the cardiopulmonary system. , 2005, Journal of the Optical Society of America. A, Optics, image science, and vision.

[6]  J. Scargle.  Studies in astronomical time series analysis. II - Statistical aspects of spectral analysis of unevenly spaced data , 1982 .

[7]  Mostefa Mesbah,et al.  A Nonstationary Model of Newborn EEG , 2007, IEEE Transactions on Biomedical Engineering.

[8]  A. Bradley,et al.  Statistical variation of aberration structure and image quality in a normal population of healthy eyes. , 2002, Journal of the Optical Society of America. A, Optics, image science, and vision.

[9]  Mark R. Morelande,et al.  Analyzing the dynamic wavefront aberrations in the human eye , 2004, IEEE Transactions on Biomedical Engineering.

[10]  Geunyoung Yoon,et al.  Changes in aberrations and retinal image quality due to tear film dynamics. , 2006, Optics express.

[11]  Mark E. J. Newman,et al.  Power-Law Distributions in Empirical Data , 2007, SIAM Rev..

[12]  Ian Munro,et al.  Benefit of higher closed-loop bandwidths in ocular adaptive optics. , 2003, Optics express.

[13]  R Navarro,et al.  Phase plates for wave-aberration compensation in the human eye. , 2000, Optics letters.

[14]  G. Arden,et al.  New methodology to measure the dynamics of ocular wave front aberrations during small amplitude changes of accommodation. , 2007, Optics express.

[15]  C Roberts,et al.  Future challenges to aberration-free ablative procedures. , 2000, Journal of refractive surgery.

[16]  Alexis Kudryashov,et al.  Adaptive optics in ophthalmology: human eye wavefront generator , 2008, SPIE BiOS.

[17]  Christopher Dainty,et al.  Coherence function analysis of the higher-order aberrations of the human eye. , 2006, Optics letters.

[18]  B Boashash,et al.  A time-frequency approach for newborn seizure detection. , 2001, IEEE engineering in medicine and biology magazine : the quarterly magazine of the Engineering in Medicine & Biology Society.

[19]  Shinozuka,et al.  Numerical method for colored-noise generation and its application to a bistable system. , 1990, Physical review. A, Atomic, molecular, and optical physics.

[20]  Michael Muma,et al.  The Role of Cardiopulmonary Signals in the Dynamics of the Eye’s Wavefront Aberrations , 2010, IEEE Transactions on Biomedical Engineering.

[21]  N. Davies,et al.  Repeatability of Ocular Wavefront Measurement , 2003, Optometry and vision science : official publication of the American Academy of Optometry.

[22]  C Leahy,et al.  Temporal dynamics and statistical characteristics of the microfluctuations of accommodation: dependence on the mean accommodative effort. , 2010, Optics express.

[23]  Arthur Bradley,et al.  A statistical model of the aberration structure of normal, well‐corrected eyes , 2002, Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians.

[24]  P Artal,et al.  Temporal dynamics of ocular aberrations: monocular vs binocular vision , 2009, Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians.

[25]  B. M. Hill,et al.  A Simple General Approach to Inference About the Tail of a Distribution , 1975 .

[26]  M. B. Priestley,et al.  Non-linear and non-stationary time series analysis , 1990 .

[27]  Mark R. Morelande,et al.  Estimating the dynamics of aberration components in the human eye , 2001, Proceedings of the 11th IEEE Signal Processing Workshop on Statistical Signal Processing (Cat. No.01TH8563).

[28]  D. Atchison,et al.  Pupil size, mean accommodation response and the fluctuations of accommodation , 1997, Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians.

[29]  N. Lomb.  Least-squares frequency analysis of unequally spaced data , 1976 .

[30]  N. Kasdin.  Discrete simulation of colored noise and stochastic processes and 1/fα power law noise generation , 1995, Proc. IEEE.