Analysis of $\pi$ -Phase-Shifted Fiber Bragg Gratings for Ultrasonic Detection

Using numerical simulations, we investigated the responses of the π -phase-shifted fiber Bragg gratings (πFBGs) impinged by pressure ultrasonic waves. The effect of the grating length, grating refractive index modification depth, and ultrasonic frequency on the wavelength sensitivity and intensity sensitivity of the πFBG ultrasonic sensor for ultrasonic waves of different wavelengths was analyzed. The directivity of a πFBG sensor was also studied. Our analysis revealed several unique πFBG response characteristics and will be useful in the design and optimization of fiber-optic ultrasonic sensors that use a πFBG as the sensing element.

[1]  M. Yamada,et al.  Analysis of almost-periodic distributed feedback slab waveguides via a fundamental matrix approach. , 1987, Applied optics.

[2]  Nobuaki Takahashi,et al.  Underwater Acoustic Sensor with Fiber Bragg Grating , 1997 .

[3]  Eric Udd,et al.  Acoustic emission detection using fiber Bragg gratings , 2001, SPIE Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[4]  Brian Culshaw,et al.  Structural Damage Location with Fiber Bragg Grating Rosettes and Lamb Waves , 2007 .

[5]  P. Laporta,et al.  Fiber strain sensor based on a pi-phase-shifted Bragg grating and the Pound-Drever-Hall technique. , 2008, Optics express.

[6]  G. Hocker Fiber-optic sensing of pressure and temperature. , 1979, Applied optics.

[7]  Jan Drewes Achenbach,et al.  RESPONSE OF AN EMBEDDED FIBER OPTIC ULTRASOUND SENSOR , 1997 .

[8]  T. Erdogan Fiber grating spectra , 1997 .

[9]  Vasilis Ntziachristos,et al.  High-sensitivity compact ultrasonic detector based on a pi-phase-shifted fiber Bragg grating. , 2011, Optics letters.

[10]  Jan Drewes Achenbach,et al.  Extrinsic and intrinsic fiber optic Sagnac ultrasound sensors , 2000 .

[11]  S. Krishnaswamy,et al.  Response of a fiber Bragg grating ultrasonic sensor , 2003 .

[12]  David J. Webb,et al.  In-fibre Bragg gratings for ultrasonic medical applications , 1997 .

[13]  A. Minardo,et al.  Response of fiber Bragg gratings to longitudinal ultrasonic waves , 2005, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[14]  J. Nye Physical Properties of Crystals: Their Representation by Tensors and Matrices , 1957 .