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Mapping transverse velocity of particles in capillary vessels by time-varying laser speckle through perturbation analyses.

ABSTRACT: We propose a cross-correlation method to map the transverse velocities of particles moving in capillary vessels using full-field time-varying laser speckle technique. The mapping is achieved by a semi-random perturbation model that describes the intensity fluctuation of time-varying laser speckle signals. When passing through probing volume, moving particles encode a random perturbation into the observed laser speckle pattern. We calculate the transverse flow velocity by cross-correlating the temporal envelopes of the perturbation signals. The proposed method is experimentally verified by the use of polymer microsphere suspension in a glass capillary.

SUBMITTER: Wang Y

PROVIDER: S-EPMC4509730 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Mapping transverse velocity of particles in capillary vessels by time-varying laser speckle through perturbation analyses.

Wang Yi Y Ma Zhenhe Z Wang Ruikang R

Optics letters 20150501 9

We propose a cross-correlation method to map the transverse velocities of particles moving in capillary vessels using full-field time-varying laser speckle technique. The mapping is achieved by a semi-random perturbation model that describes the intensity fluctuation of time-varying laser speckle signals. When passing through probing volume, moving particles encode a random perturbation into the observed laser speckle pattern. We calculate the transverse flow velocity by cross-correlating the te ...[more]

PMID: 25927742

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