Title :
Noncontact detection of ultrasound with rugged fiber-optic interferometer
Author :
Alcoz, J.J. ; Duffer, C.E. ; Nair, S.
Author_Institution :
Karta Technology Inc., San Antonio, TX, USA
Abstract :
An all-fiber-optic probe for noncontact detection of ultrasound in industrial settings is described. The probe consists of a path-matched interferometer built with polarization-maintaining optical fiber. The interferometer is maintained at its linear operating point (quadrature condition) without the need of active feedback or modulation. Ultrasound was monitored on rough metallic surfaces achieving single-pulse subnanometer sensitivity with a 5 MHz bandwidth. Probes with surface clearances of about half a centimeter were investigated. This interferometer provides immunity to ambient disturbances and a very compact package. Measurements obtained in combination with laser-generated ultrasound are also presented
Keywords :
fibre optic sensors; inspection; light interferometers; polarimetry; ultrasonic measurement; 5 MHz; Sagnac/polarimetric sensor; all-fiber-optic probe; ambient disturbance immunity; compact package; industrial settings; laser-generated ultrasound; linear operating point; noncontact ultrasound detection; nondestructive inspection; path-matched interferometer; polarization-maintaining optical fiber; quadrature condition; rough metallic surfaces; rugged fiber-optic interferometer; single-pulse subnanometer sensitivity; surface clearances; ultrasound monitoring; Bandwidth; Laser feedback; Optical feedback; Optical fiber polarization; Optical interferometry; Packaging; Probes; Rough surfaces; Surface roughness; Ultrasonic imaging;
Conference_Titel :
Ultrasonics Symposium, 1996. Proceedings., 1996 IEEE
Conference_Location :
San Antonio, TX
Print_ISBN :
0-7803-3615-1
DOI :
10.1109/ULTSYM.1996.584057
