Share Email Print

Proceedings Paper

Study of π-phase-shifted, Fiber Bragg gratings for ultrasonic detection
Author(s): Thomas Fink; Qi Zhang; Wayne Ahrens; Ming Han
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

We present a high-sensitivity fiber-optic ultrasonic sensor based on a π-phase-shifted fiber Bragg grating (πFBG). A π- phase-shift at the center of a traditional fiber Bragg grating results in the formation of a narrow-bandwidth notch in the reflection spectrum, leading to much higher sensitivity than standard fiber-Bragg-grating (FBG) sensors. A method of fabrication is introduced, including a method of removing introduced polarization dependence. A tunable-cavity diode laser is used to interrogate the πFBG by locking the wavelength to the linear slope of the spectral notch. High-sensitivity detection of ultrasonic waves is demonstrated. The directivity of the grating is characterized. The effect of strain induced polarization dependence is investigated. Preliminary tests using ultrasonic pressure waves in water are performed.

Paper Details

Date Published: 4 May 2012
PDF: 7 pages
Proc. SPIE 8370, Fiber Optic Sensors and Applications IX, 83700M (4 May 2012);
Show Author Affiliations
Thomas Fink, Univ. of Nebraska-Lincoln (United States)
Qi Zhang, Univ. of Nebraska-Lincoln (United States)
Wayne Ahrens, Univ. of Nebraska-Lincoln (United States)
Ming Han, Univ. of Nebraska-Lincoln (United States)

Published in SPIE Proceedings Vol. 8370:
Fiber Optic Sensors and Applications IX
Henry H. Du; Gary Pickrell; Eric Udd, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?