Φ80μm polarization-maintaining fiber coupler for fiber optic gyroscope

The polarization-maintaining fiber coupler (PMFC) is a kind of optical coupler manufactured with polarization-maintaining fiber (PMF). It is the pivotal device to realizing the linearly polarized light coupling, the dispersion of light as well as the multiplying. It is one of the core components of the high-precision fiber optic gyroscope (FOG) and fiber optic hydrophone. This paper reports a kind of thin-diameter PMFC (cladding diameter is 80μm), which is developed to adapt to the FOG's miniaturization. The difference between the thin-diameter PMFC (Φ80μm) and conventional PMFC (Φ125μm) in the manufacture technology has been compared. The key technologies of developing the thin-diameter PMFC (Φ80μm), such as "No tension fused taper", "On-line adjusting main axes of the PMF", "High stability package" and so on, has been discussed. In addition, it also has been carried on some Mechanical and environmental tests. The test results show that the thin-diameter PMFC can satisfy the requirements of the miniature FOG.