Regina Eckert and Zachary Phillips and Laura Waller

EECS Department, University of California, Berkeley

Technical Report No. UCB/EECS-2020-4

January 7, 2020

http://www2.eecs.berkeley.edu/Pubs/TechRpts/2020/EECS-2020-4.pdf

Fourier ptychography captures intensity images with varying source patterns (illumination angles) in order to computationally reconstruct large space-bandwidth-product images. Accurate knowledge of the illumination angles is necessary for good image quality; hence, calibration methods are crucial, despite often being impractical or slow. Here, we propose a fast, robust and accurate self-calibration algorithm that uses only experimentally-collected data and general knowledge of the illumination setup. First, our algorithm makes a fast direct estimate of the brightfield illumination angles based on image processing. Then, a more computationally-intensive spectral correlation method is used inside the iterative solver to further refine the angle estimates of both brightfield and darkfield images. We demonstrate our method for correcting large and small misalignment artifacts in both 2D and 3D Fourier ptychography with different source types: an LED array, a galvo-steered laser, and a high-NA quasi-dome LED illuminator.

Advisors: Laura Waller

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BibTeX citation:

@mastersthesis{Eckert:EECS-2020-4,
    Author= {Eckert, Regina and Phillips, Zachary and Waller, Laura},
    Title= {Efficient illumination angle self-calibration in Fourier ptychography},
    School= {EECS Department, University of California, Berkeley},
    Year= {2020},
    Month= {Jan},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2020/EECS-2020-4.html},
    Number= {UCB/EECS-2020-4},
    Abstract= {Fourier ptychography captures intensity images with varying source patterns (illumination angles) in order to computationally reconstruct large space-bandwidth-product images. Accurate knowledge of the illumination angles is necessary for good image quality; hence, calibration methods are crucial, despite often being impractical or slow. Here, we propose a fast, robust and accurate self-calibration algorithm that uses only experimentally-collected data and general knowledge of the illumination setup. First, our algorithm makes a fast direct estimate of the brightfield illumination angles based on image processing. Then, a more computationally-intensive spectral correlation method is used inside the iterative solver to further refine the angle estimates of both brightfield and darkfield images. We demonstrate our method for correcting large and small misalignment artifacts in both 2D and 3D Fourier ptychography with different source types: an LED array, a galvo-steered laser, and a high-NA quasi-dome LED illuminator.},
}

EndNote citation:

%0 Thesis
%A Eckert, Regina 
%A Phillips, Zachary 
%A Waller, Laura 
%T Efficient illumination angle self-calibration in Fourier ptychography
%I EECS Department, University of California, Berkeley
%D 2020
%8 January 7
%@ UCB/EECS-2020-4
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/2020/EECS-2020-4.html
%F Eckert:EECS-2020-4