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arXiv · 2309.08639

Live Iterative Ptychography with projection-based algorithms

Simon Welker·Tal Peer·Henry N. Chapman·Timo Gerkmann
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Abstract

In this work, we demonstrate that the ptychographic phase problem can be solved in a live fashion during scanning, while data is still being collected. We propose a generally applicable modification of the widespread projection-based algorithms such as Error Reduction (ER) and Difference Map (DM). This novel variant of ptychographic phase retrieval enables immediate visual feedback during experiments, reconstruction of arbitrary-sized objects with a fixed amount of computational resources, and adaptive scanning. By building upon the Real-Time Iterative Spectrogram Inversion (RTISI) family of algorithms from the audio processing literature, we show that live variants of projection-based methods such as DM can be derived naturally and may even achieve higher-quality reconstructions than their classic non-live counterparts with comparable effective computational load.

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Simon Welker, Tal Peer, Henry N. Chapman, Timo Gerkmann. 2023-09-19. Live Iterative Ptychography with projection-based algorithms. https://arxiv.org/abs/2309.08639

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