title: Pencil beam all-optical ultrasound imaging.
abstract: A miniature, directional fibre-optic acoustic source is presented that employs geometrical focussing to generate a nearly-collimated acoustic pencil beam. When paired with a fibre-optic acoustic detector, an all-optical ultrasound probe with an outer diameter of 2.5 mm is obtained that acquires a pulse-echo image line at each probe position without the need for image reconstruction. B-mode images can be acquired by translating the probe and concatenating the image lines, and artefacts resulting from probe positioning uncertainty are shown to be significantly lower than those observed for conventional synthetic aperture scanning of a non-directional acoustic source. The high image quality obtained for excised vascular tissue suggests that the all-optical ultrasound probe is ideally suited forin vivo, interventional applications.
authors.affiliation: Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK.
authors.forename: Erwin J
authors.initials: EJ
authors.lastname: Alles
authors.affiliation: Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK; Materials Chemistry Research Centre, UCL Department of Chemistry, London WC1H 0AJ, UK.
authors.forename: Sacha
authors.initials: S
authors.lastname: Noimark
authors.affiliation: Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK.
authors.forename: Edward
authors.initials: E
authors.lastname: Zhang
authors.affiliation: Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Beard
authors.affiliation: Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK.
authors.forename: Adrien E
authors.initials: AE
authors.lastname: Desjardins
keywords: (060.2380) Fiber optics sources and detectors; (110.2350) Fiber optics imaging; (110.5125) Photoacoustics; (170.0110) Imaging systems; (170.7170) Ultrasound