Evaluation of integrated optic modulator-based detection schemes for in-line fiber etalon sensors

This paper compares three classes of demodulation schemes for interpreting the static and dynamic response of in-line fiber etalon (ILFE) sensors. Each demodulation scheme employs path matched differential interferometry and an unbalanced integrated optic Mach-Zehnder interferometer as a readout interferometer. Active homodyne, synthetic-heterodyne and two types of pseudo-heterodyne based demodulators are evaluated. In the results presented here, signals generated by the ILFE ranging from quasistatic to about 100 Hz were recorded and compared with the signals generated by a resistance strain gauge, and were found to be in good agreement.>