Fiber optic current sensor having rotation immunity

摘要: An interferometric sensor having an optic fiber which forms a sensing loop optical path and second that is wound in the opposite direction of loop. Circularly polarized light propagates along A differential phase shift induced waves by magnetic field current conductor. The with their relationship are detected photo detector outputs electrical signal processed closure electronics into indicative current's magnitude direction. If due to rotation sensed loop, then canceled from compensating or coil may be reversed connections, flipped over, for calibrating sensor. Also, small coil, delay line coils used circuit, so bias modulation frequency can made low enough drift electronics.