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Time-reversed adapted-perturbation (TRAP) optical focusing onto dynamic objects inside scattering media.

ABSTRACT: The ability to steer and focus light inside scattering media has long been sought for a multitude of applications. To form optical foci inside scattering media, the only feasible strategy at present is to guide photons by using either implanted1 or virtual2-4 guide stars, which can be inconvenient and limits potential applications. Here, we report a scheme for focusing light inside scattering media by employing intrinsic dynamics as guide stars. By time-reversing the perturbed component of the scattered light adaptively, we show that it is possible to focus light to the origin of the perturbation. Using the approach, we demonstrate non-invasive dynamic light focusing onto moving targets and imaging of a time-variant object obscured by highly scattering media. Anticipated applications include imaging and photoablation of angiogenic vessels in tumours as well as other biomedical uses.

SUBMITTER: Ma C

PROVIDER: S-EPMC4266563 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Time-reversed adapted-perturbation (TRAP) optical focusing onto dynamic objects inside scattering media.

Ma Cheng C Xu Xiao X Liu Yan Y Wang Lihong V LV

Nature photonics 20141201 12

The ability to steer and focus light inside scattering media has long been sought for a multitude of applications. To form optical foci inside scattering media, the only feasible strategy at present is to guide photons by using either implanted<sup>1</sup> or virtual<sup>2-4</sup> guide stars, which can be inconvenient and limits potential applications. Here, we report a scheme for focusing light inside scattering media by employing intrinsic dynamics as guide stars. By time-reversing the pertur ...[more]

PMID: 25530797

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