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Title: Exceeding the limits of algorithmic self-calibrated aberration recovery in Fourier ptychography

Fourier ptychographic microscopy is a computational imaging technique that provides quantitative phase information and high resolution over a large field-of-view. Although the technique presents numerous advantages over conventional microscopy, model mismatch due to unknown optical aberrations can significantly limit reconstruction quality. A practical way of correcting for aberrations without additional data capture is through algorithmic self-calibration, in which a pupil recovery step is embedded into the reconstruction algorithm. However, software-only aberration correction is limited in accuracy. Here, we evaluate the merits of implementing a simple, dedicated calibration procedure for applications requiring high accuracy. In simulations, we find that for a target sample reconstruction error, we can image without any aberration corrections only up to a maximum aberration magnitude ofλ/40. When we use algorithmic self-calibration, we can tolerate an aberration magnitude up toλ/10 and with our proposed diffuser calibration technique, this working range is extended further toλ/3. Hence, one can trade off complexity for accuracy by using a separate calibration process, which is particularly useful for larger aberrations.

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Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Continuum
Page Range / eLocation ID:
Article No. 119
Medium: X
Sponsoring Org:
National Science Foundation
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