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Published on: January 9, 2017
Measurement of diffuse photon-pairs density wave in a multiple-scattering medium
Li-Ping Yu1, Chien Chou, Jheng-Syong Wu
1Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan.
Applied Optics
|May 13, 2008
Summary
This study experimentally verifies the diffuse photon-pairs density wave (DPPDW) theory in scattering media. DPPDW offers improved detection sensitivity for small objects compared to conventional diffuse photon density waves (DPDW).
Area of Science:
- Optics and photonics
- Biomedical optics
- Wave propagation in scattering media
Background:
- The diffuse photon-pairs density wave (DPPDW) theory was previously developed for photon propagation.
- Multiple-scattering media pose challenges for optical detection due to photon scattering.
- Conventional diffuse photon density wave (DPDW) methods have limitations in sensitivity.
Purpose of the Study:
- To experimentally study and verify the DPPDW theory in heterogeneous multiple-scattering media.
- To investigate the potential of DPPDW for enhanced detection sensitivity of small objects.
Main Methods:
- Generation of DPPDW using scattered linear polarized photon pairs (LPPPs) in a multiple-scattering medium.
- Utilizing common-path propagation of LPPPs for phase noise rejection and heterodyne detection.
- Employing polarization and spatial coherence gating to suppress scattered photons.
- Measuring DPPDW wavefront distortions caused by an embedded object via source-detector scanning.
Main Results:
- Experimental verification of the DPPDW theory in a multiple-scattering environment.
- Precise measurement of DPPDW amplitude and phase wavefront distortions.
- Observed distortions are consistent with theoretical DPPDW calculations.
- Demonstrated improved detection sensitivity for a small object compared to DPDW.
Conclusions:
- The experimental results validate the DPPDW theory in complex scattering media.
- DPPDW technology shows promise for non-invasive detection and imaging applications.
- DPPDW offers superior sensitivity for detecting small objects in scattering environments.
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