Print Email Facebook Twitter Identification of the dynamics of time-varying phase aberrations from time histories of the point-spread function Title Identification of the dynamics of time-varying phase aberrations from time histories of the point-spread function Author Doelman, R. (TU Delft Team Raf Van de Plas) Klingspor, Måns (Linköping University) Hansson, Anders (Linköping University) Löfberg, Johan (Linköping University) Verhaegen, M.H.G. (TU Delft Team Raf Van de Plas) Date 2019 Abstract To optimally compensate for time-varying phase aberrations with adaptive optics, a model of the dynamics of the aberrations is required to predict the phase aberration at the next time step. We model the time-varying behavior of a phase aberration, expressed in Zernike modes, by assuming that the temporal dynamics of the Zernike coefficients can be described by a vector-valued autoregressive (VAR) model. We propose an iterative method based on a convex heuristic for a rank-constrained optimization problem, to jointly estimate the parameters of the VAR model and the Zernike coefficients from a time series of measurements of the point-spread function (PSF) of the optical system. By assuming the phase aberration is small, the relation between aberration and PSF measurements can be approximated by a quadratic function. As such, our method is a blind identification method for linear dynamics in a stochastic Wiener system with a quadratic nonlinearity at the output and a phase retrieval method that uses a time-evolution-model constraint and a single image at every time step. To reference this document use: http://resolver.tudelft.nl/uuid:36614ab6-f219-45c2-a0ba-242160fcfe05 DOI https://doi.org/10.1364/JOSAA.36.000809 ISSN 1084-7529 Source Journal of the Optical Society of America A: Optics and Image Science, and Vision, 36 (5), 809-817 Part of collection Institutional Repository Document type journal article Rights © 2019 R. Doelman, Måns Klingspor, Anders Hansson, Johan Löfberg, M.H.G. Verhaegen Files PDF josaa_36_5_809.pdf 3.34 MB Close viewer /islandora/object/uuid:36614ab6-f219-45c2-a0ba-242160fcfe05/datastream/OBJ/view