Temperature-insensitive multipoint strain-sensing system based on fiber Bragg gratings and optical power detection scheme

• Published in: IEEE sensors journal Vol. 6; no. 2; pp. 465 - 470
• Main Authors: Chiang, Y.J., Likarn Wang, Wen-Fung Liu, Hsiao, C.S.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2006; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Bragg gratings; Capacitive sensors; Circuit stability; Circuits; Crosstalk; Divider circuit; Dividers; Fiber gratings; multipoint strain sensor; Optical crosstalk; Optical detectors; optical fiber Bragg grating (FBG); Optical fibers; Optical sensors; Ports; Sensors; source power instability; Strain; Strain measurement; Temperature sensors; temperature stability; Tensile stress
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2006.870148

This work presents a new temperature-insensitive multipoint strain sensor based on fiber Bragg gratings. A divider circuit at the post detection port compensates for optical power variation and thermal instability induced by the nonflatness of the source spectrum. Experimental results show a measurement resolution of /spl plusmn/0.35 /spl mu/S and a temperature stability of /spl plusmn/0.005% for no strain (/spl plusmn/0.48% for a strain of <400 /spl mu/S) in an example with two sensing points. A measurement linearity of /spl plusmn/0.17% is estimated in the range 0 to 350 /spl mu/S with no crosstalk.