title: Surface-bonded and embedded optical fibers as ultrasonic sensors.
abstract: The effectiveness of surface-bonded and embedded optical fibers for the detection of ultrasonic Lamb waves in 2-3-mm-thick steel, carbon-fiber-reinforced plastic (CFRP) and glass-reinforced plastic (GRP) plates are compared. A novel integrating ultrasonic sensor was achieved using the signal arm of an actively stabilized 633-nm homodyne Mach-Zehnder fiber interferometer which was either bonded directly to the plate surface or spliced to single-mode fibers embedded within a composite plate during manufacture. An embedded fiber is shown to be about 20 times more sensitive to Lamb wave motions than a surface-bonded fiber. However, the latter may be more practical.
authors.forename: S G
authors.initials: SG
authors.lastname: Pierce
authors.forename: W R
authors.initials: WR
authors.lastname: Philp
authors.forename: A
authors.initials: A
authors.lastname: Gachagan
authors.forename: A
authors.initials: A
authors.lastname: McNab
authors.forename: G
authors.initials: G
authors.lastname: Hayward
authors.forename: B
authors.initials: B
authors.lastname: Culshaw