Enhancing imaging contrast via weighted feedback for iterative multi-image phase retrieval
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Updated: Feb 15, 2026

Contrast Enhanced Vessel Imaging using MicroCT
Published on: January 27, 2011
Cheng Guo1, Qiang Li1, Xiaoqing Zhang2
1Harbin Institute of Technology, Department of Automatic Test and Control, Harbin, China.
Abstract:
Iterative phase retrieval (IPR) has developed into a feasible and simple computational method to retrieve a complex-valued sample. Due to coherent illumination, the reconstructed image quality is degraded by speckle noise arising from a laser. Accordingly, partially coherent illumination has been introduced to alleviate this restriction. We apply weighted feedback modality into multidistance and multiwavelength phase retrieval to realize high-contrast and fast imaging. In simulation, it is proved that IPR based on weighted feedback accelerates the convergence in partially coherent illumination and speckle illumination. In experiment, the resolution chart and biological specimen are reconstructed in lensless and lens-based systems, which also demonstrate the performance of weighted feedback. This work provides a simple and high-contrast imaging modality for IPR. Also, it facilitates compact and flexible experimental implementation for label-free imaging.
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