title: Super-resolution photoacoustic imaging through a scattering wall.
abstract: The use of wavefront shaping to compensate for scattering has brought a renewed interest as a potential solution to imaging through scattering walls. A key to the practicality of any imaging through scattering technique is the capability to focus light without direct access behind the scattering wall. Here we address this problem using photoacoustic feedback for wavefront optimization. By combining the spatially non-uniform sensitivity of the ultrasound transducer to the generated photoacoustic waves with an evolutionary competition among optical modes, the speckle field develops a single, high intensity focus significantly smaller than the acoustic focus used for feedback. Notably, this method is not limited by the size of the absorber to form a sub-acoustic optical focus. We demonstrate imaging behind a scattering medium using two different imaging modalities with up to ten times improvement in signal-to-noise ratio and five to six times sub-acoustic resolution.
authors.affiliation: Department of Electrical, Computer and Energy Engineering, University of Colorado at Boulder, 425 UCB, Boulder, Colorado 80309, USA.
authors.forename: Donald B
authors.initials: DB
authors.lastname: Conkey
authors.affiliation: Department of Electrical, Computer and Energy Engineering, University of Colorado at Boulder, 425 UCB, Boulder, Colorado 80309, USA.
authors.forename: Antonio M
authors.initials: AM
authors.lastname: Caravaca-Aguirre
authors.affiliation: Department of Mechanical Engineering, University of Colorado at Boulder, 427 UCB, Boulder, Colorado 80309, USA.
authors.forename: Jake D
authors.initials: JD
authors.lastname: Dove
authors.affiliation: Department of Mechanical Engineering, University of Colorado at Boulder, 427 UCB, Boulder, Colorado 80309, USA.
authors.forename: Hengyi
authors.initials: H
authors.lastname: Ju
authors.affiliation: Department of Mechanical Engineering, University of Colorado at Boulder, 427 UCB, Boulder, Colorado 80309, USA.
authors.forename: Todd W
authors.initials: TW
authors.lastname: Murray
authors.affiliation: Department of Electrical, Computer and Energy Engineering, University of Colorado at Boulder, 425 UCB, Boulder, Colorado 80309, USA.
authors.forename: Rafael
authors.initials: R
authors.lastname: Piestun