Multi-distance phase retrieval with a weighted shrink-wrap constraint. (February 2019)

• Record Type: Journal Article
• Authors: Guo, Cheng; Zhao, Yixuan; Tan, Jiubin; Liu, Shutian; Liu, Zhengjun
• Is Part Of: Optics and lasers in engineering. Volume 113(2019)
• Page Start: 1
• Page End: 5
• Publication Date: 2019-02
• Subjects: Image reconstruction techniques -- Phase retrieval -- Computational imaging; Lasers in engineering -- Periodicals; Optical measurements -- Periodicals; Optics -- Periodicals; Lasers en ingénierie -- Périodiques; Mesures optiques -- Périodiques; Optique -- Périodiques; 621.36605
• DOI: 10.1016/j.optlaseng.2018.09.017
• Languages: English
• ISSNs: 0143-8166

Abstract

Highlights: A new acceleration scheme of iterative multi-distance phase retrieval is proposed. The measurement times of diffraction patterns can be reduced to 2. The imaging contrast and convergence speed are improved. Abstract: Multi-distance phase retrieval enables a full wavefront recovery with a set of defocused intensity patterns. However, the convergence speed of multi-distance phase retrieval is restricted by a stagnant issue, which leads to a low imaging contrast for visual observation. We propose an acceleration scheme to solve this problem. A shrink-wrap constraint is imposed to obtain an efficient support region. In support region, a weighted feedback strategy is used to speed up the convergence. In non-support region, an attenuated term is introduced to eliminate redundant data. With this combined constraint, imaging contrast and convergence speed are both enhanced observably. Simulations and experiments demonstrate the validity of this acceleration scheme in a lensfree imaging system. The proposed method can both reduce the workload of experimental data acquisition and computational load.