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Experimental results are presented that provide insight into the physics of statistical imaging in heavily scattering random media based on measured speckle correlations as a function of the change in position of a moving object. In this way, definitive interpretation of a rather complex and earlier theory is achieved, making this work an experimental complement to that theory paper []. Motion could be natural, where the set of positions is estimated or separately obtained, or directed, where a mechanical stage can be used to adjust the object's position. In the experiment, a coherent laser illuminates two scattering diffusers, while an object is translated between them in the resulting speckled field and images are collected in a transmission configuration. Results are shown for various objects of differing size and geometry, allowing the theory to be validated and interpreted with new understanding. This work demonstrates imaging opportunities, and applications include material characterization, environmental imaging and sensing, and deep-tissue imaging.
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Parametrization of speckle intensity correlations over object position for coherent sensing and imaging in heavily scattering random media
A statistical treatment of speckle correlations as a function of the position of a moving object is shown to provide access to object information through thick and heavily scattering random media. Experiments for a patch-like object of varying size and for varying degree of background scatter are explained using a model, and an experimental study allows evaluation of key attributes. Given a sufficient signal-to-noise ratio, adequate coherence, and developed field statistics, measured speckle intensity patterns from a set of object positions can allow high-resolution imaging deep into an obscuring medium and the medium's scattering strength can be gauged quantitatively with calibration. This enables new opportunities in application domains such as optical sensing, material inspection, and deep tissue in vivo imaging.
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- Award ID(s):
- 1909660
- PAR ID:
- 10518038
- Publisher / Repository:
- Physical Review
- Date Published:
- Journal Name:
- Physical Review Research
- Volume:
- 2
- Issue:
- 3
- ISSN:
- 2643-1564
- Page Range / eLocation ID:
- 033148
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1103/PhysRevResearch.2.033148
