title: Thermal expansion feedback for wave-front shaping.
abstract: Focusing inside scattering media is a challenging task with a variety of applications in biomedicine. State of the art methods mostly require invasive feedback inside or behind the sample, limiting practical use. We present a technique for dynamic control and focusing inside scattering media that combines two powerful methods: optical coherence tomography (OCT) and wave-front shaping (WFS). We use OCT as a non-invasive feedback for WFS optimization of a separate, penetrating laser. Energy absorbed in the sample, creates thermal expansions that are used for the feedback mechanism. By maximizing thermal deformations within a selected focal region, we demonstrate enhanced focusing of light through scattering media beyond the ballistic regime and within the penetration range of OCT.
authors.forename: Omer
authors.initials: O
authors.lastname: Tzang
authors.forename: Eyal
authors.initials: E
authors.lastname: Niv
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Caravaca-Aguirre
authors.forename: Rafael
authors.initials: R
authors.lastname: Piestun