title: Towards new applications using capillary waveguides.
abstract: In this paper we demonstrate the enhancement of the sensing capabilities of glass capillaries. We exploit their properties as optical and acoustic waveguides to transform them potentially into high resolution minimally invasive endoscopic devices. We show two possible applications of silica capillary waveguides demonstrating fluorescence and optical-resolution photoacoustic imaging using a single 330 μm-thick silica capillary. A nanosecond pulsed laser is focused and scanned in front of a capillary by digital phase conjugation through the silica annular ring of the capillary, used as an optical waveguide. We demonstrate optical-resolution photoacoustic images of a 30 μm-thick nylon thread using the water-filled core of the same capillary as an acoustic waveguide, resulting in a fully passive endoscopic device. Moreover, fluorescence images of 1.5 μm beads are obtained collecting the fluorescence signal through the optical waveguide. This kind of silica-capillary waveguide together with wavefront shaping techniques such as digital phase conjugation, paves the way to minimally invasive multi-modal endoscopy.
authors.affiliation: Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland ; contributed equally.
authors.forename: Nicolino
authors.initials: N
authors.lastname: Stasio
authors.affiliation: Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland ; contributed equally.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shibukawa
authors.affiliation: Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Ioannis N
authors.initials: IN
authors.lastname: Papadopoulos
authors.affiliation: Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland ; Laboratory of Applied Photonics Devices, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Salma
authors.initials: S
authors.lastname: Farahi
authors.affiliation: ESPCI ParisTech, PSL Research University, CNRS, INSERM, Institut Langevin, 1 rue Jussieu, 75005 Paris, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Simandoux
authors.affiliation: Jphopto-consultant, 20 rue Campo Formio, 75013 Paris, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Huignard
authors.affiliation: ESPCI ParisTech, PSL Research University, CNRS, INSERM, Institut Langevin, 1 rue Jussieu, 75005 Paris, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Bossy
authors.affiliation: Laboratory of Applied Photonics Devices, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Christophe
authors.initials: C
authors.lastname: Moser
authors.affiliation: Laboratory of Optics, School of Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
authors.forename: Demetri
authors.initials: D
authors.lastname: Psaltis
keywords: (060.2350) Fiber optics imaging; (070.5040) Phase conjugation; (090.1995) Digital holography; (170.2150) Endoscopic imaging