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arXiv · 2206.12661

Fast generation of arbitrary optical focus array

Xin Liu·Yiwen Hu·Shijie Tu·Cuifang Kuang·Xu Liu·Xiang Hao
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Abstract

We report a novel method to generate arbitrary optical focus arrays (OFAs). Our approach rapidly produces computer-generated holograms (CGHs) to precisely control the positions and the intensities of the foci. This is achieved by replacing the fast Fourier transform (FFT) operation in the conventional iterative Fourier-transform algorithm (IFTA) with a linear algebra one, identifying/removing zero elements from the matrices, and employing a generalized weighting strategy. On the premise of accelerating the calculation speed by >70 times, we demonstrate OFA with 99% intensity precision in the experiment. Our method proves effective and is applicable for the systems in which real-time OFA generation is essential.

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Xin Liu, Yiwen Hu, Shijie Tu, Cuifang Kuang, Xu Liu, Xiang Hao. 2022-06-25. Fast generation of arbitrary optical focus array. https://doi.org/10.1016/j.optlaseng.2022.107405

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