Mechanical Strength Characteristics of Fiber Bragg Gratings Considering Fabrication Process and Reflectivity

Application fields of fiber Bragg gratings (FBGs) have gradually expanded to include primary structures as well as secondary structures and specimens. For this reason, verification for FBG reliability, such as signal characteristics and mechanical strength, has become increasingly important. In this study, the mechanical strength characteristics of FBGs of various grating lengths are investigated considering their fabrication process and reflectivity. Tension tests show that the mechanical strength of optical fibers decreases about 50% just by jacket stripping and that the amount of decrease is dependent on the stripping methods. The mechanical strength of the stripped optical fibers with gratings formed in the core decreases 55% regardless of grating lengths or reflectivity. However, the width of strength distribution increases relative to increases in reflectivity.