We report the realization of an adaptive holographic interferometer based on two-beam coupling in an optically addressed liquid crystal spatial light modulator operating at 1.55-μm. The system allows efficient phase demodulation in noisy environment and behaves as an optical high-pass filter, with a cut-off frequency of approximately 10 Hz, thus filtering slow phase disturbances (due to, for example, temperature variations or low frequency fluctuations) and keeping the detection linear without the need of heterodyne or active stabilization.

We report on the use of an adaptive holographic interferometer, based on a liquid crystal light valve, to achieve phase shift measurements in an optical fiber. Owing to the physical mechanisms involved, the interferometer adapts itself to slow phase variations. As a consequence, it is possible to use a multimode fiber for sensing, which improves the sensitivity. Moreover, a distributed architecture relying on phase-OTDR principle is presented and a localization experiment is performed.

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