Fiber-optic sensor using a tandem combination of a multimode fiber and a self-pumped phase conjugator.

An interferometric sensing scheme using a multimode fiber and a self-pumped phase conjugator is proposed. The self-pumped phase conjugator corrects the distortion due to mode scrambling in the fiber and responds to any uniform optical phase change caused by environmental factors. A temperature sensor based on the proposed scheme is used to demonstrate the feasibility of the scheme.