Polarization-maintaining Fiber Resonator Research Articles

In-line polarizer used in all-0°-splice resonator fiber-optic gyro

A method to suppress the polarization-fluctuation-induced drift in a resonator fiber-optic gyro is proposed in this paper. By inserting one in-line polarizer whose polarization extinction ratio is 30 dB into a polarization-maintaining fiber resonator with 0° polarization-axis splices, the unwanted resonance is introduced to high loss and therefore the ratio of the resonance height of the desired eigen-states of polarization (ESOP) to the unwanted ESOP is 74 dB theoretically; thus the polarization-fluctuation-induced drift is adequately suppressed. The new scheme has excellent operability and high temperature stability simultaneously. Compared to the resonator with twin 90° polarization-axis rotated splices, this scheme does not need precise length difference control. This work is of great importance in the research on resonator integrated optic gyros.

Improving thermal stability of a resonator fiber optic gyro employing a polarizing resonator

To improve the thermal stability of a resonator fiber optic gyro (R-FOG), a transmission-type polarizing resonator by inserting two in-line polarizers in a polarization-maintaining fiber resonator with twin 90° polarization-axis rotated splices is proposed and experimentally demonstrated. The in-line polarizers attenuate the unwanted resonance by introducing high loss for the unwanted eigenstates of polarization in the resonator. The desired resonance in the resonator can keep excellent stability in a wide temperature range, thus the temperature-related polarization error in the R-FOG is dramatically suppressed. Both our numerical simulation and experimental verification are carried out, which for the first time to our best knowledge demonstrate that the open-loop output of the R-FOG is insensitive to environmental temperature variations. A bias stability below 2°/h in the temperature range of 36.2°C to 33°C is successfully demonstrated.

Reduction of polarization-fluctuation induced drift in resonator fiber optic gyro by a resonator integrating in-line polarizers

A method to decrease the polarization-fluctuation induced drift in a resonator fiber optic gyro (R-FOG) is demonstrated by inserting two in-line polarizers in a polarization-maintaining fiber resonator with twin 90° polarization-axis rotated splices. The in-line polarizers attenuate the unwanted resonance by introducing high loss for the unwanted eigenstates of polarization in the resonator. Compared to the resonator without in-line polarizers, the polarization-fluctuation induced drift is reduced by 6×10(3) times. The desired resonance in the resonator can keep excellent stability in a wide temperature range; thus the temperature-dependent polarization-fluctuation drift in the R-FOG is sufficiently suppressed. A typical bias stability of 4.7°/h over 6500 s with an integration time of 10 s has been carried out. To the best of our knowledge, the long-term bias stability and high temperature stability are the best ever demonstrated in an R-FOG.

90-deg splicing error control in polarization maintaining fiber resonator based on white-light interferometry

Polarization fluctuation in polarization maintaining fiber (PMF) resonator is one of the major noise sources in resonant fiber optic gyroscope (R-FOG). 90-deg polarization-axis rotated splicing in R-FOG is an effective way to suppress the polarization-fluctuation induced noise. 90-deg polarization-axis rotated splicing error influences the noise suppression effect. Here, a polarization-coupling testing system based on white-light interferometry is designed to control 90-deg splicing error in double-coupler PMF resonator first time and a result of 0.37-deg splicing error is obtained for the first time. Then the resonant characteristics of the double-coupler PMF resonator are tested using the saw-tooth waveform scanning method. The finesse of this double-coupler PMF resonator is 24.0 and the phase interval of the two eigenstates of polarization (ESOPs) is π.

谐振式光纤陀螺保偏光纤谐振腔90°对接误差控制研究

谐振式光纤陀螺保偏光纤谐振腔90°对接误差控制研究

All-Fiber Ring Resonator Gyroscope

An all-fiber resonator optic gyroscope employing a spliceless polarization maintaining fiber resonator with 90° polarization rotation in the lapped coupler is presented. A frequency-modulation spectroscopy technique using two piezoelectric transducer phase modulators has been theoretically analyzed and experimentally demonstrated for rotation sensing. The short term bias stability better than 16°/h with integration time of 10 s has been obtained. The main error sources of optical system are discussed and some reduction measures are suggested.

Bias of an optical passive ring-resonator gyro caused by the misalignment of the polarization axis in the polarization-maintaining fiber resonator

An analysis is presented of the bias of an optical passive ring-resonator gyro caused by the misalignment of the polarization axis in the resonator formed by the polarization-maintaining fiber. A large bias takes place when the phase difference between the two polarization modes of the fiber is equal to the amount of 2 pi times an integer. It is clarified that the bias can be suppressed by setting the fiber polarizers at the lead portions of the resonator, which was a method proposed originally to reduce the bias in an ideal resonator without the misalignment.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Evaluation of the output error in an optical passive ring-resonator gyro with a 90 degrees polarization-axis rotation in the polarization-maintaining fiber resonator

A previously developed method is used to evaluate the error in the optical passive ring-resonator gyro. This scheme is shown to have sufficient accuracy to meet high-grade aircraft-navigation requirements with enough tolerance for such resonator parameters as splice misalignment, finesse, and temperature.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>