SIMULTANEOUS MEASUREMENT OF TEMPERATURE AND STRAIN - CROSS-SENSITIVITY CONSIDERATIONS

Interferometric sensors using optical fibers as a transduction medium have been shown to be sensitive to a variety of physical measurands. A result of this is that the resolution of a system designed to sense strain, for example, may be compromised by fluctuations in the temperature of the environment. We discuss the possibility of simultaneously determining the strain and temperature applied to the same piece of highly birefringent fiber. Second-order effects are shown to be important for long sensing lengths or in the presence of high strains or temperature changes. We also describe the results of experiments carried out to verify our theoretical predictions. © 1990, IEEE