Open AccessSix-pack holographic imaging for dynamic rejection of out-of-focus objects
Author(s) -
Simcha K. Mirsky,
Natan T. Shaked
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.411078
Subject(s) - focus (optics) , optics , holography , cardinal point , coherence (philosophical gambling strategy) , holographic display , fresnel number , pixel , computer science , sample (material) , artificial intelligence , computer vision , physics , diffraction , quantum mechanics , thermodynamics
Six-pack holography is adapted to reject out-of-focus objects in dynamic samples, using a single camera exposure and without any scanning. By illuminating the sample from six different angles in parallel using a low-coherence source, out-of-focus objects are laterally shifted in six different directions when projected onto the focal plane. Then pixel-wise averaging of the six reconstructed images creates a significantly clearer image, with rejection of out-of-focus objects. Dynamic imaging results are shown for swimming microalgae and flowing microbeads, including numerical refocusing by Fresnel propagation. The averaged images reduced the contribution of out-of-focus objects by up to 83% in comparison to standard holograms captured using the same light source, further improving the system sectioning capabilities. Both simulation and experimental results are presented.