A novel bend-insensitive LPFG sensor written by high-frequency CO2 laser pulses is demonstrated, for the first time, to our knowledge. Experiment results shows that the bend-sensitivity of the novel LPFG depends strongly on curved orientation. The resonant wavelength shifted merely —0. 01 8 nm even for a curvature of 1 . 1m-1at the most bend-insensitive position. Such a bend-insensitive sensor could be used to solve the problem of cross-sensitivity between bend and other measurands, such as temperature, strain or refractive index, which is an unsolved problem for LPFG sensors in practice. In addition, the bend sensitivity of the LPFG can be adjusted by selecting its circular positions.

Date Published: 9 September 2002
PDF: 5 pages
Proc. SPIE 4920, Advanced Sensor Systems and Applications, (9 September 2002);

Published in SPIE Proceedings Vol. 4920:
Advanced Sensor Systems and Applications
Yun-Jiang Rao; Julian D. C. Jones; Hiroshi Naruse; Robert I. Chen, Editor(s)