Precision and sensitivity optimization for white-light interferometric fiber-optic sensors

A detailed analysis for accuracy and sensitivity of fiber-optic sensor based on white-light interferometric technique with wavelength scanning is presented. Analytical equations for optimal optical path difference were obtained, which allow to reach the minimum measurement uncertainty. The results of the analysis can be applied for optimization of any sensor based on low coherence spectrum domain technique, though our experimental validation of analysis has been carried out with the temperature sensor based on the Sagnac interferometer having a twisted high-birefringent fiber as a sensing element.